Rak piersi u mężczyzn
Patofizjologia i mechanizm

Rak piersi u mężczyzn (MBC) stanowi około 1% wszystkich przypadków raka piersi i charakteryzuje się złożoną, wieloczynnikową patogenezą. Kluczową rolę odgrywają predyspozycje genetyczne, zwłaszcza mutacje w genie BRCA2, które zwiększają ryzyko rozwoju raka piersi u mężczyzn 80-krotnie, oraz mutacje w BRCA1, CHEK2, PALB2, ATM, RAD51C, RAD51D, BARD1 i TP53. Genomowy profil MBC częściowo pokrywa się z rakiem piersi u kobiet, z mutacjami somatycznymi w genach PIK3CA (36%) i GATA3 (15%), jednak z istotnymi różnicami molekularnymi. Zaburzenia hormonalne, takie jak podwyższony stosunek estrogenów do androgenów, są istotnym czynnikiem ryzyka, szczególnie w zespołach takich jak Klinefelter (ryzyko 20-60-krotnie wyższe), marskość wątroby, otyłość i choroby jąder. Komórki nowotworowe wykazują wysoką ekspresję receptorów hormonalnych: ER (99%), PR (82%), AR (97%) oraz HER2/neu (9%), co wpływa na mechanizmy proliferacji i potencjalne cele terapeutyczne.

  1. Patogeneza raka piersi u mężczyzn
    1. Czynniki genetyczne w patogenezie raka piersi u mężczyzn
    2. Zaburzenia hormonalne w patogenezie raka piersi u mężczyzn
    3. Mechanizm rozwoju nowotworu na poziomie komórkowym
    4. Typy histologiczne raka piersi u mężczyzn
    5. Mechanizmy regulacji epigenetycznej
    6. Czynniki środowiskowe w patogenezie raka piersi u mężczyzn
  2. Mechanizm działania receptorów hormonalnych w raku piersi u mężczyzn
    1. Rola receptora estrogenowego
    2. Rola receptora progesteronowego
    3. Rola receptora androgenowego
    4. Rola receptora HER2/neu
    5. Kompleksowe oddziaływania receptorów hormonalnych w raku piersi u mężczyzn
  3. Zróżnicowanie molekularne raka piersi u mężczyzn
    1. Podtypy molekularne raka piersi u mężczyzn
    2. Zmiany chromosomowe w raku piersi u mężczyzn
    3. Różnice w genach związanych z ruchliwością komórek
    4. Rola genu GATA3 w patogenezie raka piersi u mężczyzn
  4. Podsumowanie mechanizmów patogenetycznych
    1. Kolejne rozdziały

Patogeneza raka piersi u mężczyzn

Rak piersi u mężczyzn (Male Breast Cancer, MBC) stanowi rzadką chorobę nowotworową, odpowiadającą za około 1% wszystkich przypadków raka piersi na świecie. Mimo że jest stosunkowo rzadki, mechanizmy patogenetyczne prowadzące do rozwoju tego nowotworu są złożone i wieloczynnikowe. Etiologia raka piersi u mężczyzn pozostaje wciąż nie w pełni poznana, co wynika częściowo z jego rzadkiego występowania oraz mniejszej liczby badań w porównaniu do raka piersi u kobiet.12

Czynniki genetyczne w patogenezie raka piersi u mężczyzn

Predyspozycje genetyczne odgrywają kluczową rolę w patogenezie raka piersi u mężczyzn. Około 15-20% mężczyzn z rakiem piersi ma dodatni wywiad rodzinny w kierunku raka piersi lub jajnika, w porównaniu do 7% w populacji ogólnej.3 Najważniejsze zidentyfikowane mutacje genetyczne związane z rozwojem raka piersi u mężczyzn obejmują:

  • Mutacje genu BRCA2 – stanowią najsilniejszy czynnik ryzyka rozwoju raka piersi u mężczyzn, zwiększając ryzyko 80-krotnie w porównaniu do populacji ogólnej. Rak piersi rozwija się u około 1 na 10 mężczyzn będących nosicielami mutacji BRCA2.45
  • Mutacje genu BRCA1 – również zwiększają ryzyko, ale w mniejszym stopniu niż mutacje BRCA2.6
  • Inne mutacje genów, takie jak CHEK2, PALB2, ATM, RAD51C, RAD51D, BARD1 i TP53, które zazwyczaj są uwzględniane w panelowych badaniach genetycznych.7

Badania molekularne wykazały, że genomowy krajobraz raka piersi u mężczyzn częściowo odzwierciedla ten obserwowany u kobiet, z powtarzającymi się mutacjami somatycznymi w genach PIK3CA (36%) i GATA3 (15%). Jednak istnieją również istotne różnice, które wskazują na odrębność molekularną tego nowotworu.8 Zmiany w genie PIK3CA występują częściej u mężczyzn niż u kobiet i pojawiają się w różnych częściach genu.9

Zaburzenia hormonalne w patogenezie raka piersi u mężczyzn

Zaburzenia równowagi hormonalnej między estrogenami a androgenami odgrywają istotną rolę w patogenezie raka piersi u mężczyzn. Podwyższony stosunek estrogenów do androgenów może prowadzić do zwiększonego ryzyka rozwoju tego nowotworu.1011 Do stanów klinicznych związanych z tymi zaburzeniami należą:

  • Zespół Klinefeltera (kariotyp 47, XXY) – charakteryzujący się hipogonadyzmem, niskim poziomem testosteronu i wysokim stosunkiem estrogenów do testosteronu, zwiększający ryzyko raka piersi 20-60 razy w porównaniu do mężczyzn w populacji ogólnej.1213
  • Choroby wątroby, zwłaszcza marskość – wpływają na metabolizm steroidów i estrogenów, prowadząc do zaburzenia równowagi hormonalnej.14
  • Otyłość – związana z podwyższonym poziomem estrogenów w wyniku zwiększonej aromatyzacji obwodowej androgenów do estrogenów.15
  • Choroby jąder i niepłodność – mogą prowadzić do zaburzeń hormonalnych zwiększających ryzyko raka piersi.1617

Mechanizm działania hormonów w patogenezie raka piersi u mężczyzn związany jest z aktywacją receptorów steroidowych. Komórki raka piersi u mężczyzn charakteryzują się wysoką ekspresją receptorów hormonalnych:18

Mechanizm rozwoju nowotworu na poziomie komórkowym

Rak piersi u mężczyzn, podobnie jak u kobiet, rozpoczyna się, gdy komórki w tkance piersiowej zaczynają niekontrolowanie się namnażać. Proces obejmuje następujące etapy:19

  1. Zmiany w DNA komórek gruczołu piersiowego – mutacje prowadzą do zaburzenia naturalnych mechanizmów kontrolujących wzrost i namnażanie się komórek oraz ich zaprogramowaną śmierć (apoptozę).
  2. Niekontrolowany wzrost komórek – zmutowane komórki dzielą się szybciej i żyją dłużej niż zdrowe komórki, co prowadzi do nagromadzenia nadmiernej liczby komórek.
  3. Formowanie guza – nagromadzone komórki tworzą guz, który może naciekać okoliczne tkanki.
  4. Inwazja i przerzuty – komórki nowotworowe mogą przedostawać się do naczyń krwionośnych i limfatycznych, tworząc przerzuty w odległych narządach.20

Rak piersi u mężczyzn może rozprzestrzeniać się do układu limfatycznego, krwioobiegu lub obu tych dróg jednocześnie. Przerzuty raka piersi mogą dotyczyć wielu narządów, najczęściej płuc, wątroby, kości, mózgu i skóry.21

Typy histologiczne raka piersi u mężczyzn

Najczęstszym typem histologicznym raka piersi u mężczyzn jest inwazyjny rak przewodowy, stanowiący 85-90% wszystkich przypadków.22 Inne typy histologiczne obejmują:

  • Rak przewodowy in situ (DCIS) – przedinwazyjny lub preinwazyjny rak piersi, ograniczony do przewodów mlekowych.23
  • Inwazyjny rak zrazikowy (ILC) – niezwykle rzadki u mężczyzn ze względu na brak prawidłowej tkanki zrazikowej w męskiej piersi.24
  • Choroba Pageta brodawki sutkowej – typ raka piersi rozpoczynający się w przewodach mlekowych i rozprzestrzeniający się na brodawkę sutkową.25
  • Zapalny rak piersi – agresywny, ale rzadki typ raka piersi, powodujący obrzęk, zaczerwienienie, ocieplenie i tkliwość piersi, zamiast tworzenia guza.26

Pod względem molekularnym, większość raków piersi u mężczyzn (około 90%) jest hormonozależna (receptor estrogenowy i/lub progesteronowy dodatni), podczas gdy nadekspresja HER2 występuje w około 9-10% przypadków.2728

Mechanizmy regulacji epigenetycznej

Poza zmianami genetycznymi, w patogenezie raka piersi u mężczyzn istotną rolę odgrywają również mechanizmy epigenetyczne. Zmiany epigenetyczne często są związane z wcześniejszym wiekiem zachorowania i gorszym rokowaniem.29 Badania genomowe i transkryptomiczne dostarczyły nowych biomarkerów, które mogą pomóc w zrozumieniu podstaw genetycznych raka piersi u mężczyzn.30

Analiza chromatyny związanej z receptorami hormonów steroidowych wykazała istotne różnice w wiązaniu receptora estrogenowego (ER) z DNA u mężczyzn i kobiet. Pomimo że większość miejsc wiązania ER jest wspólna dla obu płci, miejsca wiązania związane z rokowaniem pacjentów są specyficzne dla płci.31

Czynniki środowiskowe w patogenezie raka piersi u mężczyzn

Czynniki środowiskowe również odgrywają rolę w patogenezie raka piersi u mężczyzn:32

  • Ekspozycja na promieniowanie jonizujące – wcześniejsza radioterapia, zwłaszcza w obrębie klatki piersiowej, jest istotnym czynnikiem ryzyka.3334
  • Palenie tytoniu i nadużywanie alkoholu – mogą przyczyniać się do rozwoju raka piersi u mężczyzn.35
  • Brak aktywności fizycznej – uznawany za czynnik przyczyniający się do rozwoju raka piersi u mężczyzn.36
  • Terapia hormonalna estrogenami – stosowana u mężczyzn transpłciowych, zwiększa ryzyko rozwoju raka piersi.37

Mechanizm działania receptorów hormonalnych w raku piersi u mężczyzn

Mechanizm działania receptorów hormonalnych odgrywa kluczową rolę w patogenezie i progresji raka piersi u mężczyzn. Ze względu na wysoki odsetek nowotworów hormonozależnych u mężczyzn, zrozumienie tych mechanizmów jest niezbędne do opracowania skutecznych strategii terapeutycznych.38

Rola receptora estrogenowego

Receptor estrogenowy (ER) jest wyrażany w około 99% przypadków raka piersi u mężczyzn, co jest znacząco wyższym odsetkiem niż u kobiet (77%).39 Mechanizm działania ER obejmuje:

  • Aktywację genomiczną – po związaniu estrogenu receptor przemieszcza się do jądra komórkowego, gdzie wiąże się z DNA i reguluje ekspresję genów odpowiedzialnych za proliferację komórek i ich przeżycie.40
  • Działanie niegenomiczne – aktywacja szlaków sygnałowych poza jądrem komórkowym, w tym aktywacja SRC, co może wpływać na odpowiedź na leczenie.41

Badania wykazały, że chociaż 87% raków piersi u mężczyzn jest ER-dodatnich, nowotwory te mogą wykazywać oporność na terapie anty-estrogenowe, co sugeruje złożoność mechanizmów działania ER w tej grupie pacjentów.42

Rola receptora progesteronowego

Receptor progesteronowy (PR) jest obecny w około 82% przypadków raka piersi u mężczyzn (w porównaniu do 64% u kobiet).43 Chociaż rola PR w raku piersi u mężczyzn nie jest tak dobrze poznana jak rola ER, badania sugerują, że:

  • PR moduluje wiązanie ER z DNA u kobiet, jednak u mężczyzn wiele miejsc wiązania PR jest pozbawionych ER, co sugeruje odmienną regulację genomiczną.44
  • Obecność PR jest korzystnym czynnikiem prognostycznym i predykcyjnym odpowiedzi na terapię hormonalną.45

Rola receptora androgenowego

Receptor androgenowy (AR) jest obecny w około 97% przypadków raka piersi u mężczyzn (w porównaniu do 77% u kobiet).46 Rola AR w raku piersi u mężczyzn jest wciąż nie w pełni wyjaśniona:47

  • AR może promować wzrost komórek nowotworowych w sposób podobny do ER.
  • Mutacje AR mogą być związane z rozwojem raka piersi u mężczyzn i stanowić potencjalny cel terapeutyczny.48
  • Androgeny mogą być przekształcane do estrogenów w organizmie, zwiększając stymulację estrogenową.49

Rola receptora HER2/neu

Receptor HER2/neu (ludzki receptor nabłonkowego czynnika wzrostu 2) jest nadekspresjonowany w około 9% przypadków raka piersi u mężczyzn, co jest nieco niższym odsetkiem niż u kobiet (11%).50 W przypadkach, gdy dochodzi do nadekspresji HER2:

  • HER2 działa jako istotny stymulator progresji komórek nowotworowych.51
  • Leki blokujące receptory HER2 stanowią część standardowego leczenia.52

Jednakże, raki piersi u mężczyzn są generalnie mniej prawdopodobne do wykazywania wrażliwości na terapie celowane anty-HER2 niż raki piersi u kobiet.53

Kompleksowe oddziaływania receptorów hormonalnych w raku piersi u mężczyzn

Badania sugerują złożone współdziałanie różnych receptorów hormonów steroidowych w raku piersi. Genom-wide mapping chromatyny związanej z receptorami hormonalnymi wykazał, że istnieją znaczące nakładanie się miejsc wiązania ER z AR i GR (receptorem glikokortykoidowym) u mężczyzn z rakiem piersi.54

Ciekawą obserwacją jest fakt, że większość miejsc wiązania ER zarówno u mężczyzn, jak i kobiet jest niezależna od czynnika transkrypcyjnego FOXA1 i znajduje się głównie w regionach aktywnych promotorów, co wskazuje na nowy i nieoczekiwany mechanizm funkcjonowania ER. Wyniki te stoją w zdecydowanej sprzeczności z badaniami opartymi na liniach komórkowych, które sugerowały, że większość miejsc wiązania ER współdzieli FOXA1 i znajduje się głównie w regionach wzmacniaczy (enhancerów).55

To kompleksowe oddziaływanie różnych receptorów hormonalnych przyczynia się do zróżnicowania podtypów molekularnych raka piersi u mężczyzn i może mieć implikacje dla strategii terapeutycznych.56

Zróżnicowanie molekularne raka piersi u mężczyzn

Rak piersi u mężczyzn wykazuje unikalne profile genetyczne i molekularne, które mają istotne znaczenie dla patogenezy, progresji i odpowiedzi na leczenie.57 Badania genomiczne i transkryptomiczne dostarczyły cennych informacji na temat specyficznych cech molekularnych raka piersi u mężczyzn.

Podtypy molekularne raka piersi u mężczyzn

Podobnie jak w przypadku raka piersi u kobiet, rak piersi u mężczyzn można podzielić na określone podtypy molekularne, które mają znaczenie prognostyczne i terapeutyczne:58

  • Podtyp luminalny – jest najczęstszy, charakteryzujący się ekspresją receptorów hormonalnych (ER i/lub PR).
  • Podtyp luminalny A-podobny – najczęściej mutowane geny to PIK3CA i MAP3K1 (oba w 12% przypadków).
  • Podtyp luminalny B-podobny – najczęściej mutowane geny to PIK3CA (24%) i GATA3 (21%).
  • Podtyp oporny na hormony – znacznie rzadszy, ale mogący stanowić odrębną kategorię molekularną.59

Badania wykazały, że geny regulujące funkcję chromatyny są częściej zmutowane w raku piersi u mężczyzn, a sygnatury mutacyjne 3 i 8, związane z deficytami rekombinacji homologicznej, są bardziej powszechne niż w ER/HER2-dopasowanym raku piersi u kobiet.60

Zmiany chromosomowe w raku piersi u mężczyzn

Zmiany chromosomowe są obserwowane częściej w raku piersi u mężczyzn niż u kobiet. Główne badania wykazały więcej regionów genetycznych, które błędnie zyskały materiał, i mniej takich, które straciły materiał.61 Te zmiany w liczbie kopii mogą mieć istotny wpływ na ekspresję genów i progresję nowotworu.

Amplifikacje MDM2 są częste (13%) w raku piersi u mężczyzn, korelują z nadekspresją białka (P=0,001) i prognozują złe rokowanie (P=0,007).62

Różnice w genach związanych z ruchliwością komórek

Interesującą obserwacją jest fakt, że geny związane z ruchliwością komórek są różne w raku piersi u mężczyzn w porównaniu do raka piersi u kobiet. Ta różnica może pomóc w określeniu, które leki będą skuteczne w leczeniu raka piersi u mężczyzn.63

Zróżnicowanie ekspresji genów związanych z ruchliwością komórek może mieć wpływ na zdolność komórek nowotworowych do inwazji i tworzenia przerzutów, co jest kluczowym aspektem progresji nowotworu.64

Rola genu GATA3 w patogenezie raka piersi u mężczyzn

GATA3 jest czynnikiem transkrypcyjnym z motywem palca cynkowego i odgrywa istotną rolę w normalnym rozwoju i funkcjonowaniu gruczołu sutkowego, gdzie promuje program transkrypcyjny określający tożsamość komórek przewodowych. Chociaż GATA3 został zidentyfikowany jako gen kierujący rozwojem raka piersi u kobiet i biomarker odpowiedzi na leczenie inhibitorami aromatazy, funkcja GATA3 w raku piersi u mężczyzn pozostaje kontrowersyjna.65

Mutacje w genie GATA3 są jednymi z najczęstszych zmian genetycznych obserwowanych w raku piersi u mężczyzn, występując w około 15% przypadków.66 Rola mutacji GATA3 w rozwoju i terapii anty-estrogenowej raka piersi u mężczyzn wymaga dalszych badań.67

Podsumowanie mechanizmów patogenetycznych

Patogeneza raka piersi u mężczyzn jest złożonym procesem obejmującym współdziałanie czynników genetycznych, hormonalnych, epigenetycznych i środowiskowych. Mimo podobieństw do raka piersi u kobiet, rak piersi u mężczyzn wykazuje unikalne cechy molekularne i biologiczne, które mogą wpływać na jego przebieg kliniczny i odpowiedź na leczenie.6869

Zrozumienie specyficznych mechanizmów patogenetycznych raka piersi u mężczyzn ma kluczowe znaczenie dla opracowania spersonalizowanych strategii terapeutycznych, poprawy wyników leczenia i jakości życia pacjentów. Istnieje pilna potrzeba dalszych badań w celu lepszego zrozumienia biologii tego rzadkiego nowotworu i opracowania specyficznych wytycznych leczenia.7071

Obecne badania nad rakiem piersi u mężczyzn koncentrują się na dokładniejszej charakterystyce molekularnej, identyfikacji nowych biomarkerów, opracowaniu bardziej skutecznych terapii celowanych oraz zrozumieniu mechanizmów oporności na leczenie. Postępy w tych obszarach mogą przyczynić się do poprawy opieki nad pacjentami z tym rzadkim, ale potencjalnie śmiertelnym nowotworem.72

Kolejne rozdziały

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  1. 12.04.2026
  2. www.leksykon.com.pl

Materiały źródłowe

  • #1 Male Breast Cancer
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2931115/
    Breast cancer is a rare disease in men representing nearly 1% of the total breast cancer cases worldwide. […] The gender-specific differences in breast cancer are among others related to the differing genetic and hormonal environment and the anatomic constitution in men. […] This review focuses on epidemiology, pathogenesis, and clinical findings of male breast cancer, and discusses current findings available to treat this disease. […] The etiology of MBC remains as poorly understood as that of female breast cancer, but genetic disorders and an imbalance by various mechanisms in the estrogen-testosterone ratio are probably implicated. […] Hormonal alterations due to testicular disease may be an important factor. […] The risk of breast cancer in these individuals is 2050 times higher than in 46XY men.
  • #2 Male breast cancer: a review of literature
    https://rcm.mums.ac.ir/article_8778.html
    Studies have devoted relatively scant attention to male breast cancer compared with female breast cancer. […] There is not comprehensive knowledge regarding the etiology of breast cancer in men. The environmental agents and genetic factors are proposed as the influential parameters in the pathogenesis of breast cancer. […] Male breast cancer has similar risk factors to those for postmenopausal women with breast cancer. […] Mutations in BRCA gene increase the risk of male breast cancer and BRCA2 mutation carries a higher risk of breast cancer compared to BRCA1 mutation. […] Conditions such as increasing estrogen to androgen ratio have linked to the higher risk of male breast cancer. […] It has been proposed that individuals with the history of liver disease are at higher risk of breast cancer as the result of the liver role in steroid and estrogen metabolism.
  • #3 Male Breast Cancer
    https://www.uspharmacist.com/article/male-breast-cancer
    Family history of breast cancer is a major risk factor for men. From 15% to 20% of men with breast cancer have a family history, compared with 7% of the general population. The BRCA2 gene mutation confers significant risk, but the BRCA1 mutation does not seem to increase the risk in men as it does in women. There are other genetic mutations that predispose men to breast cancer. Another risk factor involves estrogen and androgen imbalance, or the ratio of male to female hormones in the body. Other risk factors are testicular defects or injury, infertility, obesity, cirrhosis, breast trauma, gynecomastia, increasing age, Jewish ancestry, chest radiation (particularly before age 30), and estrogen exposure. Klinefelter’s syndrome, a rare genetic condition occurring in 1 of every 850 males born with two or more X chromosomes, can cause gynecomastia and also increases the risk of breast cancer; in fact, men with Klinefelter’s syndrome have a breast cancer rate approaching that of women.
  • #4 Male Breast Cancer: Can Men Get Breast Cancer? – Oncology Nurse Advisor
    https://www.oncologynurseadvisor.com/features/male-breast-cancer/
    Breast cancer in men is rare, representing just 1% of all breast cancers diagnosed per year. […] Men are often diagnosed later and have larger tumors and more lymph node involvement. […] Unfortunately, the annual incidence of the disease in males is rising. […] Since breast cancer in males, as in females, is an age-related disease, the incidence of breast cancer rises as men get older. […] For men, the risk of breast cancer is approximately doubled by having a first-degree relative with breast cancer and mutations in BRCA1 and BRCA2 are the most clearly established risk factors. […] Other studies indicated that men who carry BRCA2 mutations are at an 80-fold higher risk of developing breast cancer compared with men in the general population, with breast cancer occurring in up to 1 in 10 male BRCA2 carriers.
  • #5 Male Breast Cancer: Can Men Get Breast Cancer? – Clinical Advisor
    https://www.clinicaladvisor.com/features/male-breast-cancer/
    For men, the risk of breast cancer is approximately doubled by having a first-degree relative with breast cancer and mutations in BRCA1 and BRCA2 are the most clearly established risk factors. […] The Consortium of Investigators of Modifiers of BRCA1/2 accumulated data from 3184 BRCA1 and 2157 BRCA2 families and documented elevated risks of male breast cancer associated with pathogenic variants of BRCA1, especially with pathogenic variants of BRCA2. […] Other studies indicated that men who carry BRCA2 mutations are at an 80-fold higher risk of developing breast cancer compared with men in the general population, with breast cancer occurring in up to 1 in 10 male BRCA2 carriers. […] Male patients with BRCA1/2 mutations are also at an elevated lifetime risk of prostate and pancreas cancer, among others.
  • #6 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Radiation exposure to the chest or entire body is clearly associated with increased rates of MBC. For example, men treated with radiotherapy to the chest for thymus gland enlargement or gynecomastia have an increased rate of later developing breast cancer; men and women treated with radiotherapy for breast cancers have increased rates of developing contralateral breast cancer; and male and female survivors of the atomic bomb attacks in Japan (1945) had increased rates of developing breast cancer in proportion to their increasing levels of radiation exposure. […] The estrogen (ER), progesterone (PR), androgen (AR), and HER2/neu receptors are expressed by breast cancer cells and when active elicit various potentially pro-cancerous responses (e.g. excessive growth) in their parent cells. The percentage of cases in which breast cancer cells express an ER is 99% of males and 77% of females, the PR is 82% of males and 64% of females, an AR is 97% of males and 77% of females; and the HER2/neu is 9% of males and 11% of females.
  • #7 Breast Cancer – Gynecology and Obstetrics – Merck Manual Professional Edition
    https://www.merckmanuals.com/professional/gynecology-and-obstetrics/breast-cancer/breast-cancer
    In 2023, in men in the United States, it is estimated there will be 2800 new cases of invasive breast cancer and 530 deaths from it. Manifestations, diagnosis, and management are the same in men and women, although men tend to present at a later stage. […] Breast cancer invades locally and spreads through the regional lymph nodes, bloodstream, or both. Metastatic breast cancer may affect almost any organ in the bodymost commonly, lungs, liver, bone, brain, and skin. […] For tumors in which HER2 receptors are overexpressed, medications that block these receptors are part of standard treatment. HER2 overexpressing tumors respond well to these medications because HER2 is a significant driver of cancer cell progression. […] BRCA1 and BRCA2 gene mutations increase the risk of developing breast cancer to 70%. Prophylactic bilateral mastectomy reduces the risk of breast cancer by 90% and should be offered to women with a BRCA mutation. Other genetic mutations that increase the risk of developing breast cancer include mutations in CHEK2, PALB2, ATM, RAD51C, RAD51D, BARD1, and TP53, which are usually included in panel genetic testing.
  • #8 The molecular genetic make-up of male breast cancer in: Endocrine-Related Cancer Volume 26 Issue 10 (2019)
    https://erc.bioscientifica.com/view/journals/erc/26/10/ERC-19-0278.xml
    Male breast cancer (MBC) is extremely rare and accounts for less than 1% of all breast malignancies. […] In this study, DNA obtained from 45 formalin-fixed paraffin-embedded (FFPE) MBCs with and 90 MBCs (52 FFPE and 38 fresh-frozen) without matched normal tissues was subjected to massively parallel sequencing targeting all exons of 1943 cancer-related genes. […] The genomic landscape of MBC to some extent recapitulated that of smFBC, with recurrent PIK3CA (36%) and GATA3 (15%) somatic mutations, and with 40% of the most frequently amplified genes overlapping between both sexes. […] MDM2 amplifications were frequent (13%), correlated with protein overexpression (P=0.001) and predicted poor outcome (P=0.007). […] In conclusion, despite similarities in the genomic landscape between MBC and smFBC, MBC is a molecularly unique and heterogeneous disease requiring its own clinical trials and treatment guidelines.
  • #9 Exploring Genetic Differences in Men’s Breast Cancer
    https://www.curetoday.com/view/exploring-genetic-differences-in-mens-breast-cancer
    Changes in the PIK3CA gene are the most common mutations in male patients, occurring more frequently than in females, and in different parts of the gene. […] Chromosomal-based changes are seen more often in male breast cancer, with some major studies showing more genetic regions that have erroneously gained material, and fewer that have lost material. […] Researchers have identified several genetic subtypes that could aid in figuring out a mans prognosis. […] In addition to the typical estrogen-responsive category, it is thought that there is a much less common type of male breast cancer that is resistant to hormonal therapy. […] Another clue has emerged that may help determine which medications will work against male breast cancer: The genes associated with cell motility are different in male breast cancer than in female breast cancer.
  • #10 Male Breast Cancer – StatPearls – NCBI Bookshelf
    https://www.ncbi.nlm.nih.gov/books/NBK526036/
    Although breast cancer is typically synonymous as a disease that commonly occurs in women, it does occur in men as well. This is because although minimal in quantity, men do have breast tissue that has the potential to become malignant similarly to women, albeit much less commonly. While male breast cancer (MBC) is rare, only occurring in 1% of all breast cancers, it does occur, and it is important to be cognizant of its reality and potential. […] When discussing the etiology of breast cancer in men, one must uncover the potential genetic or environmental risk factors. Being mindful that the majority of males diagnosed with MBC have no identifiable risk other than increasing age (average age of diagnosis of 71) is important. […] The alterations in estrogen-to-androgen ratios are important to note when discussing the etiology of male breast cancer. Estrogen, which stimulates ductal development in breasts, has also been implicated as a potential risk factor for MBC, similar to women.
  • #11
    http://waocp.com/journal/index.php/apjcc/article/view/1040
    The alterations in oestrogen to androgen ratios is important in etiology of male breast cancer and carries an important role. […] Other potential triggers include obesity, marijuana use, hepatic dysfunction, thyroid disease, and oestrogen-containing medications. […] In males previous radiation therapy has been noted as a potential risk factor like females. […] In conclusion, hence, concluding from the above discussion, Male breast carcinoma presents later in life (age60years) and it presents in advance stage of carcinoma(T4). Most common histopathological subtype is infiltrating ductal carcinoma. Most of the patients are receptor positive (ER/PR).
  • #12 Can Men Get Breast Cancer? | Breast Cancer Research Foundation
    https://www.bcrf.org/blog/can-men-get-breast-cancer/
    Male breast cancer and female breast cancer typically occurs later in life, though the average age of diagnosis in men (71) is higher than women (62). […] Several factors can increase a man’s risk of developing breast cancer, but increasing age is the most common. […] About 1 in 5 men with breast cancer have a close male or female relative with the disease. […] Men can carry gene mutations associated with a higher risk of breast cancer. […] Obese men are at greater risk of breast cancer because they have more estrogen in their body than thinner men. […] Men with this congenital disease are born with an extra X chromosome and have an increased risk of breast cancer anywhere from 20 to 60 times the risk of men in the general population. […] The risk of breast cancer is higher in both men and women who have had radiation therapy for cancers in the chest, such as lymphoma.
  • #13 Male Breast Cancer: Can Men Get Breast Cancer? – Oncology Nurse Advisor
    https://www.oncologynurseadvisor.com/features/male-breast-cancer/
    Male patients with BRCA1/2 mutations are also at an elevated lifetime risk of prostate and pancreas cancer, among others. […] Klinefelters syndrome, a rare genetic syndrome characterized by a 47, XXY karyotype, hypogonadism, low testosterone levels, and a high ratio of estrogen to testosterone, is associated with a substantially higher risk of developing breast cancer. […] Since most men with breast cancer present with clinically palpable nodules, most of their cancers are invasive carcinomas, rather than ductal carcinoma-in-situ. […] Invasive ductal carcinoma is the most common histology. […] A central review of tumor samples from 1483 men with breast cancer in the International Male Breast Cancer Program found that 99% of tumors were positive for estrogen receptor, 82% were positive for progesterone receptor, and 97% were positive for androgen receptor.
  • #14 Male breast cancer: a review of literature
    https://rcm.mums.ac.ir/article_8778.html
    Studies have devoted relatively scant attention to male breast cancer compared with female breast cancer. […] There is not comprehensive knowledge regarding the etiology of breast cancer in men. The environmental agents and genetic factors are proposed as the influential parameters in the pathogenesis of breast cancer. […] Male breast cancer has similar risk factors to those for postmenopausal women with breast cancer. […] Mutations in BRCA gene increase the risk of male breast cancer and BRCA2 mutation carries a higher risk of breast cancer compared to BRCA1 mutation. […] Conditions such as increasing estrogen to androgen ratio have linked to the higher risk of male breast cancer. […] It has been proposed that individuals with the history of liver disease are at higher risk of breast cancer as the result of the liver role in steroid and estrogen metabolism.
  • #15 A case report of 29-year-old male patient with breast carcinoma
    https://www.kjco.org/journal/view.php?number=274
    Male breast cancer is a rare disease, accounting for about 1% of all breast cancers. Little is known about the etiology of male breast cancer, especially developed in young man. Genetic and hormonal factors have been reported to be involved in its pathogenesis. […] The etiology of male breast cancer is poorly understood, partly because of its relative rarity. But several risk factors have been identified, such as genetic and hormonal abnormalities. Approximately 15% to 20% of men with breast cancer report a family history of breast or ovarian cancer. […] Estrogen excess and lack of androgens contribute to several conditions associated to the risk of male breast cancer. […] It is documented the association of obesity and male breast cancer that is biologically explained by the increased peripheral aromatization of estrogen.
  • #16 Male Breast Cancer
    https://www.uspharmacist.com/article/male-breast-cancer
    Family history of breast cancer is a major risk factor for men. From 15% to 20% of men with breast cancer have a family history, compared with 7% of the general population. The BRCA2 gene mutation confers significant risk, but the BRCA1 mutation does not seem to increase the risk in men as it does in women. There are other genetic mutations that predispose men to breast cancer. Another risk factor involves estrogen and androgen imbalance, or the ratio of male to female hormones in the body. Other risk factors are testicular defects or injury, infertility, obesity, cirrhosis, breast trauma, gynecomastia, increasing age, Jewish ancestry, chest radiation (particularly before age 30), and estrogen exposure. Klinefelter’s syndrome, a rare genetic condition occurring in 1 of every 850 males born with two or more X chromosomes, can cause gynecomastia and also increases the risk of breast cancer; in fact, men with Klinefelter’s syndrome have a breast cancer rate approaching that of women.
  • #17 Male Breast Cancer
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2931115/
    Breast cancer is a rare disease in men representing nearly 1% of the total breast cancer cases worldwide. […] The gender-specific differences in breast cancer are among others related to the differing genetic and hormonal environment and the anatomic constitution in men. […] This review focuses on epidemiology, pathogenesis, and clinical findings of male breast cancer, and discusses current findings available to treat this disease. […] The etiology of MBC remains as poorly understood as that of female breast cancer, but genetic disorders and an imbalance by various mechanisms in the estrogen-testosterone ratio are probably implicated. […] Hormonal alterations due to testicular disease may be an important factor. […] The risk of breast cancer in these individuals is 2050 times higher than in 46XY men.
  • #18 Male Breast Cancer: Can Men Get Breast Cancer? – Oncology Nurse Advisor
    https://www.oncologynurseadvisor.com/features/male-breast-cancer/
    Male patients with BRCA1/2 mutations are also at an elevated lifetime risk of prostate and pancreas cancer, among others. […] Klinefelters syndrome, a rare genetic syndrome characterized by a 47, XXY karyotype, hypogonadism, low testosterone levels, and a high ratio of estrogen to testosterone, is associated with a substantially higher risk of developing breast cancer. […] Since most men with breast cancer present with clinically palpable nodules, most of their cancers are invasive carcinomas, rather than ductal carcinoma-in-situ. […] Invasive ductal carcinoma is the most common histology. […] A central review of tumor samples from 1483 men with breast cancer in the International Male Breast Cancer Program found that 99% of tumors were positive for estrogen receptor, 82% were positive for progesterone receptor, and 97% were positive for androgen receptor.
  • #19 Male breast cancer – Symptoms and causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/male-breast-cancer/symptoms-causes/syc-20374740
    Male breast cancer is a rare cancer that begins as a growth of cells in the breast tissue of men. […] Male breast cancer starts when cells in the breast tissue develop changes in their DNA. A cell’s DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. […] In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to make many more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells. […] The cancer cells might form a mass called a tumor. The tumor can grow to invade and destroy healthy body tissue. In time, cancer cells can break away and spread to other parts of the body. When cancer spreads, it’s called metastatic cancer.
  • #20 What Is Breast Cancer in Men? | Male Breast Cancer | American Cancer Society
    https://www.cancer.org/cancer/types/breast-cancer-in-men/about/what-is-breast-cancer-in-men.html
    Breast cancer can spread when the cancer cells get into the blood or lymph system and are carried to other parts of the body. […] If the cancer cells have spread to your lymph nodes, there is a higher chance that the cells could have also traveled through the lymph system and spread (metastasized) to other parts of your body. […] The most common types of breast cancer are ductal carcinoma in situ, invasive ductal carcinoma, and invasive lobular carcinoma. […] Most breast cancers are carcinomas. In fact, breast cancers are often a type of carcinoma called adenocarcinoma, which starts in cells that make glands (glandular tissue). […] Ductal carcinoma in situ (DCIS; also known as intraductal carcinoma) is considered non-invasive or pre-invasive breast cancer. […] Invasive (or infiltrating) ductal carcinoma (IDC) starts in a milk duct of the breast, breaks through the wall of the duct, and grows into the fatty tissue of the breast. Once it breaks through the wall of the duct, it has the potential to spread to other parts of the body.
  • #21 Breast Cancer – Gynecology and Obstetrics – Merck Manual Professional Edition
    https://www.merckmanuals.com/professional/gynecology-and-obstetrics/breast-cancer/breast-cancer
    In 2023, in men in the United States, it is estimated there will be 2800 new cases of invasive breast cancer and 530 deaths from it. Manifestations, diagnosis, and management are the same in men and women, although men tend to present at a later stage. […] Breast cancer invades locally and spreads through the regional lymph nodes, bloodstream, or both. Metastatic breast cancer may affect almost any organ in the bodymost commonly, lungs, liver, bone, brain, and skin. […] For tumors in which HER2 receptors are overexpressed, medications that block these receptors are part of standard treatment. HER2 overexpressing tumors respond well to these medications because HER2 is a significant driver of cancer cell progression. […] BRCA1 and BRCA2 gene mutations increase the risk of developing breast cancer to 70%. Prophylactic bilateral mastectomy reduces the risk of breast cancer by 90% and should be offered to women with a BRCA mutation. Other genetic mutations that increase the risk of developing breast cancer include mutations in CHEK2, PALB2, ATM, RAD51C, RAD51D, BARD1, and TP53, which are usually included in panel genetic testing.
  • #22 Male breast cancer | Radiology Reference Article | Radiopaedia.org
    https://radiopaedia.org/articles/male-breast-cancer?lang=us
    Male breast cancer is exceptionally rare and only accounts for less than 0.25% of male malignancies and ~0.5-1% of all breast cancer (both genders). […] Histologically, the vast majority are invasive ductal carcinoma (85-90%) or ductal carcinoma in situ. It should be noted that invasive lobular carcinoma is extremely rare in male patients because lobules and acini are not found in normal male breast tissue. […] The genetic predisposition for breast cancer can be inherited from both mother and father. First line family history includes both genders. […] Men with BRCA1/2 mutations are at increased risk for breast, prostate, pancreatic and some other cancers. The average man has a 0.1% breast cancer risk, although the risk is significantly increased to 7-8% with a BRCA2 mutation and 1% with a BRCA1 mutation. […] The overall prognosis tends to be worse than for female breast cancer, possibly due to the fact that men seek medical attention for the mass at later stages (i.e. when the mass has already become palpable).
  • #23 What Is Breast Cancer in Men? | Male Breast Cancer | American Cancer Society
    https://www.cancer.org/cancer/types/breast-cancer-in-men/about/what-is-breast-cancer-in-men.html
    Breast cancer can spread when the cancer cells get into the blood or lymph system and are carried to other parts of the body. […] If the cancer cells have spread to your lymph nodes, there is a higher chance that the cells could have also traveled through the lymph system and spread (metastasized) to other parts of your body. […] The most common types of breast cancer are ductal carcinoma in situ, invasive ductal carcinoma, and invasive lobular carcinoma. […] Most breast cancers are carcinomas. In fact, breast cancers are often a type of carcinoma called adenocarcinoma, which starts in cells that make glands (glandular tissue). […] Ductal carcinoma in situ (DCIS; also known as intraductal carcinoma) is considered non-invasive or pre-invasive breast cancer. […] Invasive (or infiltrating) ductal carcinoma (IDC) starts in a milk duct of the breast, breaks through the wall of the duct, and grows into the fatty tissue of the breast. Once it breaks through the wall of the duct, it has the potential to spread to other parts of the body.
  • #24 Male breast cancer | Radiology Reference Article | Radiopaedia.org
    https://radiopaedia.org/articles/male-breast-cancer?lang=us
    Male breast cancer is exceptionally rare and only accounts for less than 0.25% of male malignancies and ~0.5-1% of all breast cancer (both genders). […] Histologically, the vast majority are invasive ductal carcinoma (85-90%) or ductal carcinoma in situ. It should be noted that invasive lobular carcinoma is extremely rare in male patients because lobules and acini are not found in normal male breast tissue. […] The genetic predisposition for breast cancer can be inherited from both mother and father. First line family history includes both genders. […] Men with BRCA1/2 mutations are at increased risk for breast, prostate, pancreatic and some other cancers. The average man has a 0.1% breast cancer risk, although the risk is significantly increased to 7-8% with a BRCA2 mutation and 1% with a BRCA1 mutation. […] The overall prognosis tends to be worse than for female breast cancer, possibly due to the fact that men seek medical attention for the mass at later stages (i.e. when the mass has already become palpable).
  • #25 What Is Breast Cancer in Men? | Male Breast Cancer | American Cancer Society
    https://www.cancer.org/cancer/types/breast-cancer-in-men/about/what-is-breast-cancer-in-men.html
    Invasive lobular carcinoma (ILC) starts in the milk-producing glands (lobules). Like IDC, it can spread to other parts of the breast and body. […] Paget disease of the nipple is a type of breast cancer that starts in the breast ducts and spreads to the nipple. […] Inflammatory breast cancer is an aggressive, but rare type of breast cancer. It makes the breast swollen, red, warm and tender rather than forming a lump.
  • #26 What Is Breast Cancer in Men? | Male Breast Cancer | American Cancer Society
    https://www.cancer.org/cancer/types/breast-cancer-in-men/about/what-is-breast-cancer-in-men.html
    Invasive lobular carcinoma (ILC) starts in the milk-producing glands (lobules). Like IDC, it can spread to other parts of the breast and body. […] Paget disease of the nipple is a type of breast cancer that starts in the breast ducts and spreads to the nipple. […] Inflammatory breast cancer is an aggressive, but rare type of breast cancer. It makes the breast swollen, red, warm and tender rather than forming a lump.
  • #27 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Radiation exposure to the chest or entire body is clearly associated with increased rates of MBC. For example, men treated with radiotherapy to the chest for thymus gland enlargement or gynecomastia have an increased rate of later developing breast cancer; men and women treated with radiotherapy for breast cancers have increased rates of developing contralateral breast cancer; and male and female survivors of the atomic bomb attacks in Japan (1945) had increased rates of developing breast cancer in proportion to their increasing levels of radiation exposure. […] The estrogen (ER), progesterone (PR), androgen (AR), and HER2/neu receptors are expressed by breast cancer cells and when active elicit various potentially pro-cancerous responses (e.g. excessive growth) in their parent cells. The percentage of cases in which breast cancer cells express an ER is 99% of males and 77% of females, the PR is 82% of males and 64% of females, an AR is 97% of males and 77% of females; and the HER2/neu is 9% of males and 11% of females.
  • #28 Male Breast Cancer: Can Men Get Breast Cancer? – Clinical Advisor
    https://www.clinicaladvisor.com/features/male-breast-cancer/
    In general, breast cancers in men are more likely to be endocrine sensitive and less likely to be sensitive to HER2-targeted therapies than breast cancers in women. […] The standard adjuvant endocrine therapy for men with hormone receptor-positive breast cancer is 5 to 10 years of treatment with tamoxifen, with the duration of therapy determined by the risk of recurrence and side effects. […] Population-based series have shown inferior survival rates when men were treated with adjuvant aromatase inhibitors as compared with tamoxifen, perhaps due to inadequate estradiol suppression when compared with postmenopausal women. […] For men who have intolerance or contraindications to tamoxifen, GnRH analogs, with or without an aromatase inhibitor, can overcome inadequate estradiol suppression from aromatase inhibitors and can be used as an alternative therapy.
  • #29 SciELO Brazil – An introduction to male breast cancer for urologists: epidemiology, diagnosis, principles of treatment, and special situations An introduction to male breast cancer for urologists: epidemiology, diagnosis, principles of treatment, and spe
    https://www.scielo.br/j/ibju/a/rC6wRg9vxBF3pLTdy9jQ9xB/
    The existing studies indicate that risk factors linked to family history are highly relevant in this group of patients, and this information has the potential to change the entire approach when a man is diagnosed with BC, including assessing risk with the patients family. […] According to the National Comprehensive Cancer Network (NCCN) criteria (10) (2021), MaBC is a criterion for testing high-penetrance genes at any age, especially BRCA1/2, CDH1, PALB2, PTEN, and p53. […] Epigenetic events also play an important role in CMM carcinogenesis, often associated with earlier age at diagnosis, and these changes are associated with worse prognosis. […] Unlike BRCA1 mutation, BRCA2 alteration is more common in MaBC than in FBC. In high-risk families, about 60-70% of MaBC cases have a BRCA2 alteration.
  • #30 Male Breast Cancer | CancerIndex
    http://www.cancerindex.org/clinks3m.htm
    Male breast cancer is uncommon, men account for approximately 1% of all breast cancer cases. […] The majority of male breast cancers are of the infiltrating ductal type, this is where the cancer has spread beyond the cells lining ducts in the breast. […] In many respects male breast cancer is similar to that found in women, though in general men tend to be older than women at diagnosis. […] Male breast cancer (MBC) is a rare disease that accounts for less than 1% of all cancers in men and less than 1% of all diagnosed breast cancers. […] Male breast cancer (MBC) is an uncommon malignancy and accounts for only 1% of all diagnosed breast cancers. […] By using genomic and transcriptomic approaches, researchers have been able to expand our insight into the genetic basis of breast cancer, by providing new biomarkers.
  • #31 Characterizing steroid hormone receptor chromatin binding landscapes in male and female breast cancer | Nature Communications
    https://www.nature.com/articles/s41467-018-02856-2
    Although, we found the vast majority of ER sites to be shared between male and female breast cancers, ER sites that are associated with patient outcome appeared gender-selective. In line with these results, genomic selectivity of combinatorial steroid hormone receptor action is associated with the gender-specific intrinsic MBC subtypes M1 and M2. While these data suggest ER function may be driving these subtypes, causality can only be illustrated when cell line models, organoids or patient-derived xenografts are available for mechanistic studies. […] Cumulatively, we show that global ER and FOXA1 chromatin binding selectivity reveals gender-specific prognostic features that successfully classify MBC patients on survival.
  • #32 Male Breast Cancer – StatPearls – NCBI Bookshelf
    https://www.ncbi.nlm.nih.gov/books/NBK526036/
    Although breast cancer is typically synonymous as a disease that commonly occurs in women, it does occur in men as well. This is because although minimal in quantity, men do have breast tissue that has the potential to become malignant similarly to women, albeit much less commonly. While male breast cancer (MBC) is rare, only occurring in 1% of all breast cancers, it does occur, and it is important to be cognizant of its reality and potential. […] When discussing the etiology of breast cancer in men, one must uncover the potential genetic or environmental risk factors. Being mindful that the majority of males diagnosed with MBC have no identifiable risk other than increasing age (average age of diagnosis of 71) is important. […] The alterations in estrogen-to-androgen ratios are important to note when discussing the etiology of male breast cancer. Estrogen, which stimulates ductal development in breasts, has also been implicated as a potential risk factor for MBC, similar to women.
  • #33 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Radiation exposure to the chest or entire body is clearly associated with increased rates of MBC. For example, men treated with radiotherapy to the chest for thymus gland enlargement or gynecomastia have an increased rate of later developing breast cancer; men and women treated with radiotherapy for breast cancers have increased rates of developing contralateral breast cancer; and male and female survivors of the atomic bomb attacks in Japan (1945) had increased rates of developing breast cancer in proportion to their increasing levels of radiation exposure. […] The estrogen (ER), progesterone (PR), androgen (AR), and HER2/neu receptors are expressed by breast cancer cells and when active elicit various potentially pro-cancerous responses (e.g. excessive growth) in their parent cells. The percentage of cases in which breast cancer cells express an ER is 99% of males and 77% of females, the PR is 82% of males and 64% of females, an AR is 97% of males and 77% of females; and the HER2/neu is 9% of males and 11% of females.
  • #34
    http://waocp.com/journal/index.php/apjcc/article/view/1040
    The alterations in oestrogen to androgen ratios is important in etiology of male breast cancer and carries an important role. […] Other potential triggers include obesity, marijuana use, hepatic dysfunction, thyroid disease, and oestrogen-containing medications. […] In males previous radiation therapy has been noted as a potential risk factor like females. […] In conclusion, hence, concluding from the above discussion, Male breast carcinoma presents later in life (age60years) and it presents in advance stage of carcinoma(T4). Most common histopathological subtype is infiltrating ductal carcinoma. Most of the patients are receptor positive (ER/PR).
  • #35 Breast Cancer in Men: An Overview of General Features and Molecular Pathology
    https://www.onlinescientificresearch.com/articles/breast-cancer-in-men-an-overview-of-general-features-and-molecular-pathology.html
    MBC often presents unique genetic and molecular profiles. […] Men with mutations in the BRCA1 and BRCA2 genes are at a significantly higher risk of developing breast cancer. […] A family history of breast cancer elevates the risk of developing MBC. […] Men who have elevated levels of estrogen have an increased risk of acquiring breast cancer. […] Excessive exposure to radiation especially to the chest area or the treatment of other cancers can elevate the risk for MBC. […] Lifestyle factors such as smoking and a lack of physical exercise are contributing factors to MBC. […] Transgender men who undergo estrogen hormone therapy have an elevated risk of developing MBC. […] The detection of MBC typically consisted of thorough physical and clinical examinations. […] The histopathology of MBC is an important area of study because of the rarity and subtle biological differences as compared to womens breast cancer cases.
  • #36 Breast Cancer in Men: An Overview of General Features and Molecular Pathology
    https://www.onlinescientificresearch.com/articles/breast-cancer-in-men-an-overview-of-general-features-and-molecular-pathology.html
    MBC often presents unique genetic and molecular profiles. […] Men with mutations in the BRCA1 and BRCA2 genes are at a significantly higher risk of developing breast cancer. […] A family history of breast cancer elevates the risk of developing MBC. […] Men who have elevated levels of estrogen have an increased risk of acquiring breast cancer. […] Excessive exposure to radiation especially to the chest area or the treatment of other cancers can elevate the risk for MBC. […] Lifestyle factors such as smoking and a lack of physical exercise are contributing factors to MBC. […] Transgender men who undergo estrogen hormone therapy have an elevated risk of developing MBC. […] The detection of MBC typically consisted of thorough physical and clinical examinations. […] The histopathology of MBC is an important area of study because of the rarity and subtle biological differences as compared to womens breast cancer cases.
  • #37 Breast Cancer in Men: An Overview of General Features and Molecular Pathology
    https://www.onlinescientificresearch.com/articles/breast-cancer-in-men-an-overview-of-general-features-and-molecular-pathology.html
    MBC often presents unique genetic and molecular profiles. […] Men with mutations in the BRCA1 and BRCA2 genes are at a significantly higher risk of developing breast cancer. […] A family history of breast cancer elevates the risk of developing MBC. […] Men who have elevated levels of estrogen have an increased risk of acquiring breast cancer. […] Excessive exposure to radiation especially to the chest area or the treatment of other cancers can elevate the risk for MBC. […] Lifestyle factors such as smoking and a lack of physical exercise are contributing factors to MBC. […] Transgender men who undergo estrogen hormone therapy have an elevated risk of developing MBC. […] The detection of MBC typically consisted of thorough physical and clinical examinations. […] The histopathology of MBC is an important area of study because of the rarity and subtle biological differences as compared to womens breast cancer cases.
  • #38 Hormone Therapy for Breast Cancer in Men | American Cancer Society
    https://www.cancer.org/cancer/types/breast-cancer-in-men/treating/hormone-therapy.html
    Hormone therapy (sometimes called endocrine therapy) is a way to treat cancer by using hormones or drugs or other treatments that affect hormones. Hormone therapy is a form of systemic therapy, meaning it can reach nearly all parts of the body. […] Some breast cancers grow in response to the hormones estrogen or progesterone. Estrogen and progesterone are usually thought of as female hormones, but men have them in their bodies, too, just at lower levels. […] About 9 of 10 breast cancers in men are hormone receptor-positive, meaning they are estrogen receptor (ER)-positive, progesterone receptor (PR)-positive, or both. This makes them more likely to respond to hormone treatments. Hormone therapy does not help people whose tumors are both ER- and PR-negative. […] Surgical removal of the testicles (orchiectomy) is another way to regulate hormones that might affect breast cancer growth. Removing the testicles greatly lowers the levels of testosterone and other androgens (male hormones). Most male breast cancers have androgen receptors that may cause the cells to grow. Androgens can also be converted into estrogens in the body. […] Orchiectomy shrinks most male breast cancers, and it may help make other treatments like tamoxifen more likely to work.
  • #39 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Radiation exposure to the chest or entire body is clearly associated with increased rates of MBC. For example, men treated with radiotherapy to the chest for thymus gland enlargement or gynecomastia have an increased rate of later developing breast cancer; men and women treated with radiotherapy for breast cancers have increased rates of developing contralateral breast cancer; and male and female survivors of the atomic bomb attacks in Japan (1945) had increased rates of developing breast cancer in proportion to their increasing levels of radiation exposure. […] The estrogen (ER), progesterone (PR), androgen (AR), and HER2/neu receptors are expressed by breast cancer cells and when active elicit various potentially pro-cancerous responses (e.g. excessive growth) in their parent cells. The percentage of cases in which breast cancer cells express an ER is 99% of males and 77% of females, the PR is 82% of males and 64% of females, an AR is 97% of males and 77% of females; and the HER2/neu is 9% of males and 11% of females.
  • #40 Characterizing steroid hormone receptor chromatin binding landscapes in male and female breast cancer | Nature Communications
    https://www.nature.com/articles/s41467-018-02856-2
    The majority of male (and female) breast cancers are hormonally driven, where ER genomic action dictates transcriptional programs that drive tumor cell proliferation. Analogous to the female counterpart, male breast cancers are treated with endocrine therapies (such as tamoxifen) to block ER transcriptional activity, yet relapse after hormonal treatment has also been noted. Even though the genomic action of ER in MBC remains completely elusive, multiple reports have studied ER genomics in the female disease. […] AR expression is frequently observed in most male (and female) breast cancers, although its role in breast cancer is poorly understood. AR activation in breast cancer cells facilitates downstream gene expression that drives tumorigenesis in a similar manner to ER. This tumorigenic action of AR is most extensively studied in prostate cancer, where differential AR-DNA binding profiles can classify prostate cancer patients on outcome.
  • #41
    https://journals.indianapolis.iu.edu/index.php/IMPRS/article/view/27933
    In 2023, 2,800 men are expected to be diagnosed with breast cancer in the United States, and while it affects a smaller patient population, breast cancer in men has a 19% higher mortality rate. […] Even though 87% of male breast cancers are estrogen receptor positive (ER+), breast cancer in men is resistant to anti-estrogen therapies. […] RNA-Seq identified an upregulation of ESR1 which correlates with increased ER+ male breast cancer, along with upregulation of non-genomic ER signaling pathway, including SRC activation, which may affect treatment response. […] This first characterization and modeling of mens breast epithelial cells provides the basis for determining the mechanism behind the lack of efficacy of anti-estrogen therapeutics.
  • #42
    https://journals.indianapolis.iu.edu/index.php/IMPRS/article/view/27933
    In 2023, 2,800 men are expected to be diagnosed with breast cancer in the United States, and while it affects a smaller patient population, breast cancer in men has a 19% higher mortality rate. […] Even though 87% of male breast cancers are estrogen receptor positive (ER+), breast cancer in men is resistant to anti-estrogen therapies. […] RNA-Seq identified an upregulation of ESR1 which correlates with increased ER+ male breast cancer, along with upregulation of non-genomic ER signaling pathway, including SRC activation, which may affect treatment response. […] This first characterization and modeling of mens breast epithelial cells provides the basis for determining the mechanism behind the lack of efficacy of anti-estrogen therapeutics.
  • #43 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Radiation exposure to the chest or entire body is clearly associated with increased rates of MBC. For example, men treated with radiotherapy to the chest for thymus gland enlargement or gynecomastia have an increased rate of later developing breast cancer; men and women treated with radiotherapy for breast cancers have increased rates of developing contralateral breast cancer; and male and female survivors of the atomic bomb attacks in Japan (1945) had increased rates of developing breast cancer in proportion to their increasing levels of radiation exposure. […] The estrogen (ER), progesterone (PR), androgen (AR), and HER2/neu receptors are expressed by breast cancer cells and when active elicit various potentially pro-cancerous responses (e.g. excessive growth) in their parent cells. The percentage of cases in which breast cancer cells express an ER is 99% of males and 77% of females, the PR is 82% of males and 64% of females, an AR is 97% of males and 77% of females; and the HER2/neu is 9% of males and 11% of females.
  • #44 Characterizing steroid hormone receptor chromatin binding landscapes in male and female breast cancer | Nature Communications
    https://www.nature.com/articles/s41467-018-02856-2
    MBC is ER-driven. Therefore, a one-to-one comparison of binding sites of ER with each factor was performed, where only samples were analyzed in which both ER and the other factor were profiled. A significant proportion of ER binding sites overlap with AR and GR sites as seen in cell line data which we confirmed in MBC. Interestingly, although PR modulates ER binding in FBC, many PR sites in MBC were devoid of ER. […] Our findings have indicated that the majority of ER binding sites in both male and female breast tumors are FOXA1-independent and are found at active promoter regions, indicating a novel and unexpected mode of ER function. These results are in stark contrast to cell line-based studies that illustrated the majority of ER sites shared with FOXA1, mainly found at enhancers. Our findings highlight the necessity to address transcription factor functioning in the physiological context of human tissue, rather than limiting analyses to cell line models.
  • #45 Breast Cancer in Men: A Systematic Review of the Literature from the Arab World
    https://clinmedjournals.org/articles/ijor/international-journal-of-oncology-research-ijor-5-042.php?jid=ijor
    Breast Cancer (BC) is the most frequent cancer worldwide accounting for 11.7% of all cancers but only for 1% of men’s cancers; therefore, men’s breast cancer is rarely discussed, especially in the Arab World. […] There are multiple risk factors incriminated in the pathogenesis of BC. The first category includes genetic risk factors, with BRCA1 and 2 mutations being the most frequent genetic alterations causing BC. […] The mutation of the BRCA2 gene puts men in a higher risk of BC. […] Hormone Receptors are important prognostic and treatment predicting indicators in BC. […] When it comes to treating BC in men, guidelines are very similar to those in women. […] The European Society of Medical Oncology recommends modified radical mastectomy followed by a hormonal therapy for HR positive tumors or otherwise chemotherapy.
  • #46 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Radiation exposure to the chest or entire body is clearly associated with increased rates of MBC. For example, men treated with radiotherapy to the chest for thymus gland enlargement or gynecomastia have an increased rate of later developing breast cancer; men and women treated with radiotherapy for breast cancers have increased rates of developing contralateral breast cancer; and male and female survivors of the atomic bomb attacks in Japan (1945) had increased rates of developing breast cancer in proportion to their increasing levels of radiation exposure. […] The estrogen (ER), progesterone (PR), androgen (AR), and HER2/neu receptors are expressed by breast cancer cells and when active elicit various potentially pro-cancerous responses (e.g. excessive growth) in their parent cells. The percentage of cases in which breast cancer cells express an ER is 99% of males and 77% of females, the PR is 82% of males and 64% of females, an AR is 97% of males and 77% of females; and the HER2/neu is 9% of males and 11% of females.
  • #47 Male Breast Cancer
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2931115/
    The role of the androgen receptor in MBC is unclear. […] Male breast cancers have high rates of hormone receptor expression. […] The predominant histological type of disease is invasive ductal which forms more than 90% of all male breast tumors. […] The role of taxanes or dose-dense chemotherapy in MBC has not been adequately established. […] There is a substantial need to obtain more detailed information about the etiology, pathogenesis, and clinical aspects of MBC as well as therapeutic options.
  • #48
    https://journals.lww.com/ijpm/fulltext/2021/64010/potential_role_of_significant_gata3_mutation_in.32.aspx
    Previous studies showed that AR mutation was related to the development of male breast cancer and proposed as a new target for treatment of male breast cancer. […] GATA3 is a zinc finger transcriptional factor and plays an essential role in the normal development and function of the mammary gland where it promotes a transcriptional program specifying luminal cell identity. […] Although GATA3 was identified as a driver gene of female breast cancer and a biomarker of response to aromatase inhibitor therapy, function of GATA3 in male breast cancer remains controversial, and roles of GATA3 mutation in the development and anti-estrogen endocrine therapy of male breast cancer necessitate further study.
  • #49 Hormone Therapy for Breast Cancer in Men | American Cancer Society
    https://www.cancer.org/cancer/types/breast-cancer-in-men/treating/hormone-therapy.html
    Hormone therapy (sometimes called endocrine therapy) is a way to treat cancer by using hormones or drugs or other treatments that affect hormones. Hormone therapy is a form of systemic therapy, meaning it can reach nearly all parts of the body. […] Some breast cancers grow in response to the hormones estrogen or progesterone. Estrogen and progesterone are usually thought of as female hormones, but men have them in their bodies, too, just at lower levels. […] About 9 of 10 breast cancers in men are hormone receptor-positive, meaning they are estrogen receptor (ER)-positive, progesterone receptor (PR)-positive, or both. This makes them more likely to respond to hormone treatments. Hormone therapy does not help people whose tumors are both ER- and PR-negative. […] Surgical removal of the testicles (orchiectomy) is another way to regulate hormones that might affect breast cancer growth. Removing the testicles greatly lowers the levels of testosterone and other androgens (male hormones). Most male breast cancers have androgen receptors that may cause the cells to grow. Androgens can also be converted into estrogens in the body. […] Orchiectomy shrinks most male breast cancers, and it may help make other treatments like tamoxifen more likely to work.
  • #50 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Radiation exposure to the chest or entire body is clearly associated with increased rates of MBC. For example, men treated with radiotherapy to the chest for thymus gland enlargement or gynecomastia have an increased rate of later developing breast cancer; men and women treated with radiotherapy for breast cancers have increased rates of developing contralateral breast cancer; and male and female survivors of the atomic bomb attacks in Japan (1945) had increased rates of developing breast cancer in proportion to their increasing levels of radiation exposure. […] The estrogen (ER), progesterone (PR), androgen (AR), and HER2/neu receptors are expressed by breast cancer cells and when active elicit various potentially pro-cancerous responses (e.g. excessive growth) in their parent cells. The percentage of cases in which breast cancer cells express an ER is 99% of males and 77% of females, the PR is 82% of males and 64% of females, an AR is 97% of males and 77% of females; and the HER2/neu is 9% of males and 11% of females.
  • #51 Breast Cancer – Gynecology and Obstetrics – Merck Manual Professional Edition
    https://www.merckmanuals.com/professional/gynecology-and-obstetrics/breast-cancer/breast-cancer
    In 2023, in men in the United States, it is estimated there will be 2800 new cases of invasive breast cancer and 530 deaths from it. Manifestations, diagnosis, and management are the same in men and women, although men tend to present at a later stage. […] Breast cancer invades locally and spreads through the regional lymph nodes, bloodstream, or both. Metastatic breast cancer may affect almost any organ in the bodymost commonly, lungs, liver, bone, brain, and skin. […] For tumors in which HER2 receptors are overexpressed, medications that block these receptors are part of standard treatment. HER2 overexpressing tumors respond well to these medications because HER2 is a significant driver of cancer cell progression. […] BRCA1 and BRCA2 gene mutations increase the risk of developing breast cancer to 70%. Prophylactic bilateral mastectomy reduces the risk of breast cancer by 90% and should be offered to women with a BRCA mutation. Other genetic mutations that increase the risk of developing breast cancer include mutations in CHEK2, PALB2, ATM, RAD51C, RAD51D, BARD1, and TP53, which are usually included in panel genetic testing.
  • #52 Breast Cancer – Gynecology and Obstetrics – Merck Manual Professional Edition
    https://www.merckmanuals.com/professional/gynecology-and-obstetrics/breast-cancer/breast-cancer
    In 2023, in men in the United States, it is estimated there will be 2800 new cases of invasive breast cancer and 530 deaths from it. Manifestations, diagnosis, and management are the same in men and women, although men tend to present at a later stage. […] Breast cancer invades locally and spreads through the regional lymph nodes, bloodstream, or both. Metastatic breast cancer may affect almost any organ in the bodymost commonly, lungs, liver, bone, brain, and skin. […] For tumors in which HER2 receptors are overexpressed, medications that block these receptors are part of standard treatment. HER2 overexpressing tumors respond well to these medications because HER2 is a significant driver of cancer cell progression. […] BRCA1 and BRCA2 gene mutations increase the risk of developing breast cancer to 70%. Prophylactic bilateral mastectomy reduces the risk of breast cancer by 90% and should be offered to women with a BRCA mutation. Other genetic mutations that increase the risk of developing breast cancer include mutations in CHEK2, PALB2, ATM, RAD51C, RAD51D, BARD1, and TP53, which are usually included in panel genetic testing.
  • #53 Male Breast Cancer: Can Men Get Breast Cancer? – Oncology Nurse Advisor
    https://www.oncologynurseadvisor.com/features/male-breast-cancer/
    In general, breast cancers in men are more likely to be endocrine sensitive and less likely to be sensitive to HER2-targeted therapies than breast cancers in women. […] The standard adjuvant endocrine therapy for men with hormone receptor-positive breast cancer is 5 to 10 years of treatment with tamoxifen, with the duration of therapy determined by the risk of recurrence and side effects.
  • #54 Characterizing steroid hormone receptor chromatin binding landscapes in male and female breast cancer | Nature Communications
    https://www.nature.com/articles/s41467-018-02856-2
    MBC is ER-driven. Therefore, a one-to-one comparison of binding sites of ER with each factor was performed, where only samples were analyzed in which both ER and the other factor were profiled. A significant proportion of ER binding sites overlap with AR and GR sites as seen in cell line data which we confirmed in MBC. Interestingly, although PR modulates ER binding in FBC, many PR sites in MBC were devoid of ER. […] Our findings have indicated that the majority of ER binding sites in both male and female breast tumors are FOXA1-independent and are found at active promoter regions, indicating a novel and unexpected mode of ER function. These results are in stark contrast to cell line-based studies that illustrated the majority of ER sites shared with FOXA1, mainly found at enhancers. Our findings highlight the necessity to address transcription factor functioning in the physiological context of human tissue, rather than limiting analyses to cell line models.
  • #55 Characterizing steroid hormone receptor chromatin binding landscapes in male and female breast cancer | Nature Communications
    https://www.nature.com/articles/s41467-018-02856-2
    MBC is ER-driven. Therefore, a one-to-one comparison of binding sites of ER with each factor was performed, where only samples were analyzed in which both ER and the other factor were profiled. A significant proportion of ER binding sites overlap with AR and GR sites as seen in cell line data which we confirmed in MBC. Interestingly, although PR modulates ER binding in FBC, many PR sites in MBC were devoid of ER. […] Our findings have indicated that the majority of ER binding sites in both male and female breast tumors are FOXA1-independent and are found at active promoter regions, indicating a novel and unexpected mode of ER function. These results are in stark contrast to cell line-based studies that illustrated the majority of ER sites shared with FOXA1, mainly found at enhancers. Our findings highlight the necessity to address transcription factor functioning in the physiological context of human tissue, rather than limiting analyses to cell line models.
  • #56 Exploring Genetic Differences in Men’s Breast Cancer
    https://www.curetoday.com/view/exploring-genetic-differences-in-mens-breast-cancer
    Changes in the PIK3CA gene are the most common mutations in male patients, occurring more frequently than in females, and in different parts of the gene. […] Chromosomal-based changes are seen more often in male breast cancer, with some major studies showing more genetic regions that have erroneously gained material, and fewer that have lost material. […] Researchers have identified several genetic subtypes that could aid in figuring out a mans prognosis. […] In addition to the typical estrogen-responsive category, it is thought that there is a much less common type of male breast cancer that is resistant to hormonal therapy. […] Another clue has emerged that may help determine which medications will work against male breast cancer: The genes associated with cell motility are different in male breast cancer than in female breast cancer.
  • #57 Breast Cancer in Men: An Overview of General Features and Molecular Pathology
    https://www.onlinescientificresearch.com/articles/breast-cancer-in-men-an-overview-of-general-features-and-molecular-pathology.html
    MBC often presents unique genetic and molecular profiles. […] Men with mutations in the BRCA1 and BRCA2 genes are at a significantly higher risk of developing breast cancer. […] A family history of breast cancer elevates the risk of developing MBC. […] Men who have elevated levels of estrogen have an increased risk of acquiring breast cancer. […] Excessive exposure to radiation especially to the chest area or the treatment of other cancers can elevate the risk for MBC. […] Lifestyle factors such as smoking and a lack of physical exercise are contributing factors to MBC. […] Transgender men who undergo estrogen hormone therapy have an elevated risk of developing MBC. […] The detection of MBC typically consisted of thorough physical and clinical examinations. […] The histopathology of MBC is an important area of study because of the rarity and subtle biological differences as compared to womens breast cancer cases.
  • #58 The molecular genetic make-up of male breast cancer in: Endocrine-Related Cancer Volume 26 Issue 10 (2019)
    https://erc.bioscientifica.com/view/journals/erc/26/10/ERC-19-0278.xml
    Major genetic factors associated with an increased risk of MBC include BRCA2 and BRCA1 germline mutations, Klinefelter syndrome (KS) and family history. […] The majority of MBCs are invasive ductal carcinomas with high estrogen (ER) and progesterone (PR) receptor levels without overexpression of HER2. […] Recent large-scale cross-platform projects have provided a detailed characterization of the genomic landscape of FBC. […] Genomic data on MBC are scarce. […] On a molecular level, like FBC, MBC is a heterogeneous disease with differences in transcriptional, copy number, microRNA and methylation patterns. […] Thus, MBCs share many features with FBCs, but there is evidence for distinct differences with potential implications for clinical management. […] The most frequently mutated genes in luminal A-like MBC included PIK3CA and MAP3K1 (both at 12%), whereas the most frequently mutated genes in luminal B-like MBC were PIK3CA (24%) and GATA3 (21%). […] Overall, genes regulating chromatin function appear more often mutated in MBC, and mutational signatures 3 and 8, both associated with homologous recombination deficiency, are more prevalent than in ER/HER2-matched FBC.
  • #59 Exploring Genetic Differences in Men’s Breast Cancer
    https://www.curetoday.com/view/exploring-genetic-differences-in-mens-breast-cancer
    Changes in the PIK3CA gene are the most common mutations in male patients, occurring more frequently than in females, and in different parts of the gene. […] Chromosomal-based changes are seen more often in male breast cancer, with some major studies showing more genetic regions that have erroneously gained material, and fewer that have lost material. […] Researchers have identified several genetic subtypes that could aid in figuring out a mans prognosis. […] In addition to the typical estrogen-responsive category, it is thought that there is a much less common type of male breast cancer that is resistant to hormonal therapy. […] Another clue has emerged that may help determine which medications will work against male breast cancer: The genes associated with cell motility are different in male breast cancer than in female breast cancer.
  • #60 The molecular genetic make-up of male breast cancer in: Endocrine-Related Cancer Volume 26 Issue 10 (2019)
    https://erc.bioscientifica.com/view/journals/erc/26/10/ERC-19-0278.xml
    Major genetic factors associated with an increased risk of MBC include BRCA2 and BRCA1 germline mutations, Klinefelter syndrome (KS) and family history. […] The majority of MBCs are invasive ductal carcinomas with high estrogen (ER) and progesterone (PR) receptor levels without overexpression of HER2. […] Recent large-scale cross-platform projects have provided a detailed characterization of the genomic landscape of FBC. […] Genomic data on MBC are scarce. […] On a molecular level, like FBC, MBC is a heterogeneous disease with differences in transcriptional, copy number, microRNA and methylation patterns. […] Thus, MBCs share many features with FBCs, but there is evidence for distinct differences with potential implications for clinical management. […] The most frequently mutated genes in luminal A-like MBC included PIK3CA and MAP3K1 (both at 12%), whereas the most frequently mutated genes in luminal B-like MBC were PIK3CA (24%) and GATA3 (21%). […] Overall, genes regulating chromatin function appear more often mutated in MBC, and mutational signatures 3 and 8, both associated with homologous recombination deficiency, are more prevalent than in ER/HER2-matched FBC.
  • #61 Exploring Genetic Differences in Men’s Breast Cancer
    https://www.curetoday.com/view/exploring-genetic-differences-in-mens-breast-cancer
    Changes in the PIK3CA gene are the most common mutations in male patients, occurring more frequently than in females, and in different parts of the gene. […] Chromosomal-based changes are seen more often in male breast cancer, with some major studies showing more genetic regions that have erroneously gained material, and fewer that have lost material. […] Researchers have identified several genetic subtypes that could aid in figuring out a mans prognosis. […] In addition to the typical estrogen-responsive category, it is thought that there is a much less common type of male breast cancer that is resistant to hormonal therapy. […] Another clue has emerged that may help determine which medications will work against male breast cancer: The genes associated with cell motility are different in male breast cancer than in female breast cancer.
  • #62 The molecular genetic make-up of male breast cancer in: Endocrine-Related Cancer Volume 26 Issue 10 (2019)
    https://erc.bioscientifica.com/view/journals/erc/26/10/ERC-19-0278.xml
    Male breast cancer (MBC) is extremely rare and accounts for less than 1% of all breast malignancies. […] In this study, DNA obtained from 45 formalin-fixed paraffin-embedded (FFPE) MBCs with and 90 MBCs (52 FFPE and 38 fresh-frozen) without matched normal tissues was subjected to massively parallel sequencing targeting all exons of 1943 cancer-related genes. […] The genomic landscape of MBC to some extent recapitulated that of smFBC, with recurrent PIK3CA (36%) and GATA3 (15%) somatic mutations, and with 40% of the most frequently amplified genes overlapping between both sexes. […] MDM2 amplifications were frequent (13%), correlated with protein overexpression (P=0.001) and predicted poor outcome (P=0.007). […] In conclusion, despite similarities in the genomic landscape between MBC and smFBC, MBC is a molecularly unique and heterogeneous disease requiring its own clinical trials and treatment guidelines.
  • #63 Exploring Genetic Differences in Men’s Breast Cancer
    https://www.curetoday.com/view/exploring-genetic-differences-in-mens-breast-cancer
    Changes in the PIK3CA gene are the most common mutations in male patients, occurring more frequently than in females, and in different parts of the gene. […] Chromosomal-based changes are seen more often in male breast cancer, with some major studies showing more genetic regions that have erroneously gained material, and fewer that have lost material. […] Researchers have identified several genetic subtypes that could aid in figuring out a mans prognosis. […] In addition to the typical estrogen-responsive category, it is thought that there is a much less common type of male breast cancer that is resistant to hormonal therapy. […] Another clue has emerged that may help determine which medications will work against male breast cancer: The genes associated with cell motility are different in male breast cancer than in female breast cancer.
  • #64 Male breast cancer – Symptoms and causes – Mayo Clinic
    https://www.mayoclinic.org/diseases-conditions/male-breast-cancer/symptoms-causes/syc-20374740
    Male breast cancer is a rare cancer that begins as a growth of cells in the breast tissue of men. […] Male breast cancer starts when cells in the breast tissue develop changes in their DNA. A cell’s DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. […] In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to make many more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells. […] The cancer cells might form a mass called a tumor. The tumor can grow to invade and destroy healthy body tissue. In time, cancer cells can break away and spread to other parts of the body. When cancer spreads, it’s called metastatic cancer.
  • #65
    https://journals.lww.com/ijpm/fulltext/2021/64010/potential_role_of_significant_gata3_mutation_in.32.aspx
    Previous studies showed that AR mutation was related to the development of male breast cancer and proposed as a new target for treatment of male breast cancer. […] GATA3 is a zinc finger transcriptional factor and plays an essential role in the normal development and function of the mammary gland where it promotes a transcriptional program specifying luminal cell identity. […] Although GATA3 was identified as a driver gene of female breast cancer and a biomarker of response to aromatase inhibitor therapy, function of GATA3 in male breast cancer remains controversial, and roles of GATA3 mutation in the development and anti-estrogen endocrine therapy of male breast cancer necessitate further study.
  • #66 The molecular genetic make-up of male breast cancer in: Endocrine-Related Cancer Volume 26 Issue 10 (2019)
    https://erc.bioscientifica.com/view/journals/erc/26/10/ERC-19-0278.xml
    Male breast cancer (MBC) is extremely rare and accounts for less than 1% of all breast malignancies. […] In this study, DNA obtained from 45 formalin-fixed paraffin-embedded (FFPE) MBCs with and 90 MBCs (52 FFPE and 38 fresh-frozen) without matched normal tissues was subjected to massively parallel sequencing targeting all exons of 1943 cancer-related genes. […] The genomic landscape of MBC to some extent recapitulated that of smFBC, with recurrent PIK3CA (36%) and GATA3 (15%) somatic mutations, and with 40% of the most frequently amplified genes overlapping between both sexes. […] MDM2 amplifications were frequent (13%), correlated with protein overexpression (P=0.001) and predicted poor outcome (P=0.007). […] In conclusion, despite similarities in the genomic landscape between MBC and smFBC, MBC is a molecularly unique and heterogeneous disease requiring its own clinical trials and treatment guidelines.
  • #67
    https://journals.lww.com/ijpm/fulltext/2021/64010/potential_role_of_significant_gata3_mutation_in.32.aspx
    Previous studies showed that AR mutation was related to the development of male breast cancer and proposed as a new target for treatment of male breast cancer. […] GATA3 is a zinc finger transcriptional factor and plays an essential role in the normal development and function of the mammary gland where it promotes a transcriptional program specifying luminal cell identity. […] Although GATA3 was identified as a driver gene of female breast cancer and a biomarker of response to aromatase inhibitor therapy, function of GATA3 in male breast cancer remains controversial, and roles of GATA3 mutation in the development and anti-estrogen endocrine therapy of male breast cancer necessitate further study.
  • #68 Male breast cancer – Wikipedia
    https://en.wikipedia.org/wiki/Male_breast_cancer
    Male breast cancer (MBC) is a cancer in males that originates in their breasts. Males account for less than 1% of new breast cancers with about 20,000 new cases being diagnosed worldwide every year. Its incidence rates in males vs. females are, respectively, 0.4 and 66.7 per 100,000 person-years. The worldwide incidences of male as well as female breast cancers have been increasing over the last few decades. Currently, one of every 800 men are estimated to develop this cancer during their lifetimes. […] Because it has a far lower incidence in males and because large-scale breast cancer studies have routinely excluded males, current knowledge of male breast cancer is far less than female breast cancer and often rests on small, retrospective, single-center studies. Consequently, the majority of strategies for evaluating and treating MBC have been adopted from those used for female breast cancer. However, MBC appears to have some features that warrant clinical approaches differing from those for female breast cancer. Features of male breast cancers that differ from those in females include variations in their presentations, associations with other diseases, associations with non-medical predisposing conditions, expressions of key breast cancer-related hormones, causes (including frequency and forms of genetic alterations), tumor types, and treatments.
  • #69 The molecular genetic make-up of male breast cancer in: Endocrine-Related Cancer Volume 26 Issue 10 (2019)
    https://erc.bioscientifica.com/view/journals/erc/26/10/ERC-19-0278.xml
    Major genetic factors associated with an increased risk of MBC include BRCA2 and BRCA1 germline mutations, Klinefelter syndrome (KS) and family history. […] The majority of MBCs are invasive ductal carcinomas with high estrogen (ER) and progesterone (PR) receptor levels without overexpression of HER2. […] Recent large-scale cross-platform projects have provided a detailed characterization of the genomic landscape of FBC. […] Genomic data on MBC are scarce. […] On a molecular level, like FBC, MBC is a heterogeneous disease with differences in transcriptional, copy number, microRNA and methylation patterns. […] Thus, MBCs share many features with FBCs, but there is evidence for distinct differences with potential implications for clinical management. […] The most frequently mutated genes in luminal A-like MBC included PIK3CA and MAP3K1 (both at 12%), whereas the most frequently mutated genes in luminal B-like MBC were PIK3CA (24%) and GATA3 (21%). […] Overall, genes regulating chromatin function appear more often mutated in MBC, and mutational signatures 3 and 8, both associated with homologous recombination deficiency, are more prevalent than in ER/HER2-matched FBC.
  • #70 Male Breast Cancer
    https://pmc.ncbi.nlm.nih.gov/articles/PMC2931115/
    The role of the androgen receptor in MBC is unclear. […] Male breast cancers have high rates of hormone receptor expression. […] The predominant histological type of disease is invasive ductal which forms more than 90% of all male breast tumors. […] The role of taxanes or dose-dense chemotherapy in MBC has not been adequately established. […] There is a substantial need to obtain more detailed information about the etiology, pathogenesis, and clinical aspects of MBC as well as therapeutic options.
  • #71 Male breast cancer: a review of literature
    https://rcm.mums.ac.ir/article_8778.html
    The most common pathological subtype of male breast cancer is invasive ductal carcinoma, similar to females. […] The most common subtype is hormone receptor-positive subtype with approximately 20% to 40% of HER-2 positive. […] The etiology of male breast cancer and identification of the most effective therapeutic strategy are still under consideration. Further investigations are required to clarify the exact biological properties, efficacy of various treatments, and the quality of life in men with breast cancer.
  • #72 A case report of 29-year-old male patient with breast carcinoma
    https://www.kjco.org/journal/view.php?number=274
    Some studies found slightly elevated risk of male breast cancer associated with a history of diabetes. […] However, many studies have lacked information about the type and severity of diabetes, making the interpretation of various findings difficult. […] There is still a paucity of randomized controlled trials and treatment for male breast cancer is based on treatment for female breast cancer. […] Recently, there has been an increase in the incidence of male breast cancer, along with the increase in female breast cancer. Further research in the understanding of male breast cancer is warranted to better guide treatment decision-making in these patients. […] Some studies have found the distribution of tumor subtypes in male breast cancer to be different compared with female breast cancer, which may point to important differences in biology and outcomes. […] Advancements in the characterization and genomic mapping of male breast cancer have been discussed. It is hoped that these huge efforts for rare disease are able to derive more results for understanding of male breast cancer.

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podtyp luminalny zapalny rak piersi inwazyjny rak zrazikowy inwazyjny rak przewodowy czynnik transkrypcyjny terapia hormonalna receptor HER2 terapia antyestrogenowa radioterapia terapia celowana mutacja BRCA1 receptor estrogenowy zespół Klinefeltera mutacja BRCA2 gen PIK3CA mechanizm patogenetyczny receptor progesteronowy rak przewodowy in situ hipogonadyzm ekspresja genu marskość wątroby równowaga hormonalna inhibitor aromatazy biomarker rak piersi u mężczyzn mutacja somatyczna promieniowanie jonizujące receptor androgenowy choroba Pageta brodawki sutkowej