Ameloblastoma – Epidemiologia

Ameloblastoma
Epidemiologia

Ameloblastoma to rzadki, łagodny nowotwór nabłonkowy pochodzenia zębopochodnego, charakteryzujący się lokalnie agresywnym przebiegiem i wysokim wskaźnikiem nawrotów (~22%, z połową nawrotów w ciągu 5 lat po leczeniu). Globalna zapadalność wynosi około 0,92 przypadku na milion osobolat (95% CI: 0,57-1,49), z wyraźnymi różnicami geograficznymi i rasowymi – wyższa u populacji afrykańskiej i azjatyckiej. Ameloblastoma najczęściej dotyka pacjentów w wieku 20-40 lat (średni wiek diagnozy 39 lat), z lekką przewagą mężczyzn (stosunek mężczyzn do kobiet 1,2-1,4:1). Lokalizacyjnie przeważa w tylnej części żuchwy (80% przypadków), z stosunkiem żuchwa:szczęka górna od 6,43:1 do 10:1. Typy histologiczne obejmują konwencjonalny (71,3%), jednokomorowy, obwodowy i przerzutowy, różniące się epidemiologią i agresywnością. Leczenie konwencjonalnego typu najczęściej polega na resekcji segmentalnej (45%) lub łyżeczkowaniu z krioterapią (40%), z podejściem radykalnym preferowanym w celu zmniejszenia nawrotów.

Epidemiologia Ameloblastoma

Ameloblastoma jest rzadkim, łagodnym guzem nabłonkowym pochodzenia zębopochodnego, który wykazuje znaczące różnice w występowaniu w zależności od regionu geograficznego, wieku, płci i rasy. Pomimo swojej rzadkości, stanowi on istotne wyzwanie kliniczne ze względu na swój lokalnie agresywny charakter oraz wysoki wskaźnik nawrotów¹².

Występowanie globalne

Globalna zapadalność na ameloblastoma została określona na poziomie 0,92 przypadku na milion osobolat (95% CI: 0,57-1,49), co czyni go rzadkim nowotworem³. Niektóre badania wskazują na nieco niższą zapadalność wynoszącą około 0,5 nowego przypadku na milion osób rocznie⁴⁵. Ameloblastoma stanowi około 1% wszystkich guzów szczęki i żuchwy, ale jest drugim najczęstszym guzem zębopochodnym (odontoma jest najczęstszym ogółem, ale ameloblastoma jest najczęstszą zmianą przeświecającą)⁶⁷.

Istnieją wyraźne różnice geograficzne w występowaniu ameloblastoma. W porównaniu do krajów zachodnich, wyższą zapadalność odnotowuje się w Afryce, Chinach i Indiach⁴⁸. Badanie przeprowadzone w Indiach wykazało całkowitą częstość występowania ameloblastoma wśród wszystkich zmian jamy ustnej na poziomie 2,18% zmian głowy i szyi⁹.

Różnice rasowe i etniczne

Dane dotyczące predylekcji rasowej są niejednoznaczne. Niektóre badania wskazują, że nie ma predylekcji rasowej dla ameloblastoma, podczas gdy inne sugerują zwiększoną częstość występowania u osób rasy czarnej⁵⁸. Roczne wskaźniki zapadalności na 100 000 osób zostały określone jako 1,96 dla czarnych mężczyzn, 1,20 dla czarnych kobiet, 0,18 dla białych mężczyzn i 0,44 dla białych kobiet¹⁰¹¹.

Badanie przeprowadzone w północno-wschodnim regionie Brazylii wykazało stosunek czarnych do białych pacjentów wynoszący 2:1, sugerując, że czynniki rasowe mogą mieć silny wpływ na występowanie ameloblastoma w regionach, gdzie większość ludności ma pochodzenie afrykańskie¹²¹³.

Wiek i płeć

Ameloblastoma może występować w szerokim zakresie wieku, ale najczęściej dotyka pacjentów w wieku od 20 do 40 lat, przy czym średni wiek w momencie diagnozy wynosi 39 lat⁶⁵. Szczyt występowania przypada na trzecią do piątej dekady życia, ze spadkiem częstości wraz z wiekiem¹². Ameloblastoma jest rzadki u dzieci poniżej 10 roku życia⁶.

Dane dotyczące predylekcji płciowej również są niejednoznaczne. Niektóre badania wskazują na równe występowanie u mężczyzn i kobiet⁵¹⁴, podczas gdy inne pokazują lekką przewagę mężczyzn, z proporcją mężczyzn do kobiet wynoszącą około 1,2:1 do 1,4:1⁵¹⁵. Interesujące jest to, że kobiety mają tendencję do zachorowania około 4 lat wcześniej niż mężczyźni, a guzy wydają się być większe u kobiet⁵.

Podtypy ameloblastoma i ich epidemiologia

Ameloblastoma klasyfikuje się na cztery główne typy, które różnią się pod względem epidemiologii i zachowania klinicznego¹⁶:

Ameloblastoma konwencjonalny – najczęstszy typ (71,3% przypadków), diagnozowany głównie w czwartej dekadzie życia (58,7%), z lekką predylekcją do mężczyzn, zlokalizowany głównie w tylnym regionie żuchwy (91,8%)¹⁷¹⁸.
Ameloblastoma jednokomorowy – mniej agresywny, występuje głównie u młodszych pacjentów w trzeciej dekadzie życia (75,6%), z predylekcją do tylnego regionu żuchwy (92%)¹⁸.
Ameloblastoma obwodowy – rzadki typ, występujący na dziąsłach i tkankach jamy ustnej w górnej lub dolnej szczęce, szczyt występowania przypada na piątą do siódmej dekady życia¹⁶¹⁹.
Ameloblastoma przerzutowy – bardzo rzadki typ, definiowany przez komórki guza występujące z dala od pierwotnego miejsca w szczęce¹⁶.

Lokalizacja anatomiczna

Ameloblastoma ma wyraźną predylekcję do występowania w żuchwie (80%) w porównaniu do szczęki górnej (20%), a częściej występuje w tylnej części żuchwy niż w przedniej²⁰. Stosunek przypadków występujących w żuchwie do szczęki górnej może wynosić od 6,43:1 do nawet 10:1²¹.

Ameloblastoma szczęki górnej jest wyjątkowo rzadki, stanowiąc tylko 15% wszystkich ameloblastomów²². Warto zauważyć, że ameloblastomy szczęki górnej występują około 10 lat później niż te powstające w żuchwie, prawdopodobnie z powodu braku wyraźnych wczesnych objawów²².

Nawroty i przeżycie

Pomimo swojego łagodnego charakteru, ameloblastoma ma znaczącą skłonność do nawrotów. Ogólny wskaźnik nawrotów wynosi około 22%, przy czym połowa z nich pojawia się 5 lat po początkowym leczeniu chirurgicznym². Nawroty obserwowano w 13,2% przypadków przy średnim czasie obserwacji wynoszącym 10 lat, z czego 16 dotyczyło konwencjonalnego ameloblastoma, a 2 guzów jednokomorowych¹⁸.

Leczenie wyboru dla większości przypadków konwencjonalnego ameloblastoma to resekcja segmentalna (45%), następnie łyżeczkowanie z krioterapią (40%), a pozostałe (15%) były leczone tylko łyżeczkowaniem¹⁸. Radykalne leczenie jest częściej stosowane w celu zmniejszenia wskaźnika nawrotów, podczas gdy środki zachowawcze są zwykle zachowywane u dzieci i młodzieży²³.

Ameloblastoma złośliwy

Złośliwy ameloblastoma, obejmujący ameloblastoma przerzutujący i raka ameloblastycznego, stanowi 1,6-2,2% wszystkich guzów zębopochodnych²⁴. Ogólny wskaźnik zapadalności na złośliwego ameloblastoma wynosił 1,79 na 10 milionów osób/rok, przy czym wskaźnik zapadalności był wyższy u mężczyzn niż u kobiet i wyższy u populacji czarnej niż białej²⁵²⁶.

Mediana ogólnego przeżycia wynosiła 17,6 roku od momentu diagnozy, a rosnący wiek był związany ze statystycznie istotnym gorszym przeżyciem²⁶. Szacuje się, że co roku tylko 1 na 1 milion osób jest diagnozowanych z ameloblastoma, a tylko 2% z tych osób ma złośliwego ameloblastoma¹⁴.

Nowe metody nadzoru i diagnostyki

Trudności związane z wczesną diagnozą ameloblastoma wynikają głównie z braku specyficznych biomarkerów i odpowiednich metod obrazowania przesiewowego¹. Ostatnie badania zidentyfikowały unikalne sygnatury niekodującego RNA (ncRNA) związane z ameloblastoma, które mogą służyć jako potencjalne biomarkery dla wczesnego wykrywania i monitorowania guza²⁷.

Pięć unikalnych ncRNA – LINC340, SNORD116-25, SNORA11, SNORA21 i SNORA65 – wykazuje silne powiązanie z ameloblastoma, niezależnie od mutacji BRAF-V600E i SMO-L412F, typu histologicznego czy lokalizacji guza, ale pozytywnie koreluje z rozmiarem guza¹²⁷. Cechy ncRNA, takie jak przydatność do wykrywania molekularnego i biodostępność w płynach ustrojowych, sprzyjają rozwojowi bardziej czułych badań przesiewowych PCR zarówno na biopsjach punkcyjnych, jak i biopsjach płynnych²⁷.

Wpływ pandemii COVID-19 na nadzór

Pandemia COVID-19 miała znaczący wpływ na diagnostykę i leczenie ameloblastoma. Środki wprowadzone w celu zapobiegania i kontroli rozprzestrzeniania się COVID-19, takie jak konwersja jednostek medycznych na oddziały opieki COVID-19, ograniczenie liczby hospitalizacji, opóźnienie rutynowej opieki oraz stosowanie telemedycyny jako substytutu konsultacji klinicznej, wpłynęły negatywnie na jakość opieki²⁸.

Ponadto, strach przed zakażeniem wirusowym spowodował niechęć pacjentów do poszukiwania pomocy medycznej. Zmiany te doprowadziły do opóźnień diagnostycznych i gorszych wyników terapeutycznych w szeregu schorzeń, w tym ameloblastoma²⁸.

Znaczenie danych epidemiologicznych

Dokładne oszacowanie częstości występowania i zapadalności na ameloblastoma jest niezbędne do planowania usług zdrowotnych i społecznych, które będą wymagane do radzenia sobie z tą enigmatyczną zmianą²⁹. Trendy w rozkładzie jakiejkolwiek zmiany wykazują różnice regionalne i czasowe, dlatego okresowe i długoterminowe przedstawianie ich danych demograficznych zapewnia dokładniejsze i aktualne informacje, które są dostępne dla klinicystów lub badaczy⁹.

Mimo że podgrupy ameloblastoma różnią się zachowaniem biologicznym, obecne dane są istotne jako podstawowe odniesienia dla klinicystów i patologów¹⁵. Zrozumienie zachowania tego guza jest niezbędne, aby uniknąć miejscowej chorobowości i zwiększonych wskaźników nawrotów¹⁸.

Cecha epidemiologiczna	Dane	Źródło
Globalna zapadalność	0,92 przypadku na milion osobolat (95% CI: 0,57-1,49)	³
Alternatywne dane o zapadalności	0,5 nowego przypadku na milion osób rocznie	⁴⁵
Zapadalność na złośliwego ameloblastoma	1,79 na 10 milionów osób/rok	²⁵
Zapadalność według rasy i płci (na 100 000)	1,96 (czarni mężczyźni), 1,20 (czarne kobiety), 0,18 (biali mężczyźni), 0,44 (białe kobiety)	¹⁰¹¹
Stosunek mężczyzn do kobiet	1,2:1 do 1,4:1	⁵¹⁵
Średni wiek diagnozy	39 lat	⁵
Najczęstszy przedział wiekowy	20-40 lat (szczyt w 3-5 dekadzie)	⁶⁷
Stosunek żuchwa:szczęka górna	6,43:1 do 10:1	²¹
Wskaźnik nawrotów	Około 22% (połowa w ciągu 5 lat po leczeniu)	²
Mediana przeżycia dla złośliwego ameloblastoma	17,6 lat od momentu diagnozy	²⁶

Kolejne rozdziały

Zapraszamy do dalszego czytania naszego leksykonu.

Wybierz kolejny rozdział z menu poniżej, aby otworzyć nową podstronę kompedium wiedzy i uzyskać szczegółowe informację o leku, substancji lub chorobie.

Materiały źródłowe

#1 Ameloblastoma RNA profiling uncovers a distinct non-coding RNA signature | Oncotarget
https://www.oncotarget.com/article/13889/text/
Ameloblastoma of the jaws remains the top difficult to treat odontogenic tumour and has a high recurrence rate. […] Here we present the first report of ameloblastoma ncRNA signatures. […] Importantly, the presence of these ncRNAs was independent of BRAF-V600E and SMO-L412F mutations, histology type or tumour location, but was positively correlated with the tumour size. […] This study shows a systematic investigation of ncRNA expression of ameloblastoma, and illuminates new diagnostic and therapeutic targets for this invasive odontogenic tumour. […] Ameloblastoma remains the top difficult to treat odontogenic tumour and has a high recurrence rate. […] It is difficult to diagnose early, mainly due to the lack of screening imaging modalities and specific biomarkers. […] Here we employed a global transcriptome approach to examine total ameloblastoma associated RNA in a two-step analysis; firstly, whole transcriptome profiling by microarray and secondly validation of ncRNAs with RT and qPCR assays.
#2 Head and Neck: Odontogenic tumor: Ameloblastoma
https://atlasgeneticsoncology.org/solid-tumor/5945/head-and-neck-odontogenic-tumor-ameloblastoma
Ameloblastoma although rare, is the most common odontogenic tumor accounting for 1% of all tumors in head and neck region and around 11% of all odontogenic tumors. […] They usually occur in middle age group i.e. 20-40 years with highest incidence noted in 33 years. […] They are rare in children (8.7% – 15%). […] Ameloblastoma occurs in all areas of jaws, but the mandible is the most commonly affected area i.e. more than 80% of cases are seen here. […] Based on the clinical, radiographic, histopathologic and behavioral aspects, four subtypes of ameloblastoma are currently identified namely:- Classic/solid/multicystic ameloblastoma- Unicystic ameloblastoma- Peripheral ameloblastoma- Desmoplastic ameloblastoma. […] Reichart et al. reveal that the overall recurrence rate is around 22% and half of them appear 5 years after the initial surgical management. […] A recurrence rate of 8% has been reported and a further and wider local excision can be curative.
#3 Global incidence and profile of ameloblastoma: A systematic review and meta-analysis – PubMed
https://pubmed.ncbi.nlm.nih.gov/30614154/
Objectives: To evaluate the global incidence of ameloblastoma and to provide a profile of ameloblastoma patients. […] Seven studies on the incidence rate of ameloblastoma were included in the meta-analysis. These studies only covered Europe, Africa, and Australia. The pooled incidence rate was 0.92 per million person-years (95% CI: 0.57-1.49), with significant heterogeneity between studies. […] This is the first study assessing the global incidence of ameloblastoma. The pooled incidence rate was determined to be 0.92 per million person-years.
#4 Azthena logo with the word Azthena
https://www.news-medical.net/health/What-is-Ameloblastoma.aspx
Ameloblastoma is an uncommon disease, with an annual incidence of 0.5 new cases per 1,000,000 individuals. […] There are, however, geographical distinctions: In comparison to the Western World, Africa, China, and India have higher incidences. Ameloblastomas are most commonly found between the ages of 30 and 60 (average of 36 years) with a peak around the fifth decade. […] The ratio of males to females is 1.2:1. Ameloblastomas make up 1% of all tumors in the head and neck. Ameloblastomas are the most prevalent kind of odontogenic tumor, accounting for about 18% of all cases.
#5 Ameloblastoma epidemiology and demographics – wikidoc
https://www.wikidoc.org/index.php/Ameloblastoma_epidemiology_and_demographics
The incidence of ameloblastoma is approximately 1.96, 1.20, 0.18, and 0.44 per 100,000 for black males, black females, white males, and white females respectively, worldwide. Ameloblastoma affects men and women equally. There is no racial predilection to the ameloblastoma. Ameloblastoma usually occur in middle age group i.e. 20-40 years; the median age at diagnosis is 39 years. […] The incidence of ameloblastoma is approximately 0.5 new cases in 1,000,000 people, worldwide. […] Ameloblastoma affects men and women almost equally. Although, women tend to be 4 years younger than men when tumors first occur and tumors appear to be larger in females. […] The male to female ratio is approximately 1.2:1. […] There is no racial predilection to the ameloblastoma. However, there is conflicting evidence on the incidence rates in different races.
#6 Ameloblastoma – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK545165/
Ameloblastomas represent about 1% of all jaw tumors, but they are the second-most common odontogenic tumor. […] Ameloblastomas can occur over a broad age range, and most commonly affect patients between the ages of 20 to 40 years. They are uncommon in children younger than ten years. […] Rizzitelli A et al. conducted a population-based study of malignant ameloblastoma to determine its incidence rate and absolute survival. They looked at 293 patients across the United States and found that the overall incidence rate of malignant ameloblastoma was 1.79 per 10 million persons/year. […] The rate of incidence was higher in males than females and also higher in the black versus white population. […] They also found that malignant ameloblastoma, comprising the two types, metastasizing ameloblastoma, and ameloblastic carcinoma, represents 1.6 to 2.2% of all odontogenic tumors. […] Their findings confirmed previous epidemiologic research, which showed the male to female ratio to be between 2.3 and 5. […] Malignant variations of the ameloblastoma can occur between the teenage years up to older age.
#7 Ameloblastoma | Radiology Reference Article | Radiopaedia.org
https://radiopaedia.org/articles/ameloblastoma?embed_domain=external.radpair.com%27%5B0%5D%27%5B0%5Dfavicon.ico&lang=us
Ameloblastomas are the second most common odontogenic tumor (odontoma is the most common overall, but ameloblastoma is the most common lucent lesion) and account for up to one-third of such cases. […] They are slow-growing and tend to present in the 3rd to 5th decades of life, with no gender predilection.
#8 Ameloblastoma epidemiology and demographics – wikidoc
https://www.wikidoc.org/index.php/Ameloblastoma_epidemiology_and_demographics
Although some reports claim an increased incidence of ameloblastoma in black individuals, a large study identifies Asians as the population with greatest number of affected patients. […] Ameloblastoma is by far the most common unequivocal odontogenic neoplasm in all ethnic groups, representing approximately 1% of head and neck neoplasms in Europe and the USA, some studies claim that it has the highest incidence in Afro-Caribbean populations. […] Ameloblastoma commonly affects adults than younger people, the median age at diagnosis is 39 years. […] They are slow growing and tend to present in the 3rd to 5th decades of life. […] Maxillary and extraosseous ameloblastoma commonly affects individuals in a slightly older age group while unicystic and granular cell ameloblastoma occur in a younger age group. […] The average age of unicystic ameloblastoma is 10.8 years. […] The majority of ameloblastoma cases are reported in Africa, China, and India.
#9 Clinicopathological and Demographic Characteristics of 171 Cases of Ameloblastoma: A 40-Year Retrospective Institutional Study in Maharashtra – Global Journal of Medical Pharmaceutical and Biomedical Update
https://gjmpbu.org/clinicopathological-and-demographic-characteristics-of-171-cases-of-ameloblastoma-a-40-year-retrospective-institutional-study-in-maharashtra/
Ameloblastoma (AM) is the most common benign odontogenic neoplasm. Changing trends and geographic variation necessitate the conduction of periodic demographic studies to update the existing demographic data pertaining to AM. The present research aims to further append the existing yet limited demographic data available on AM in India. […] An overall incidence rate of AM among all oral lesions was found to be 2.18% of head and neck lesions. […] AM constitutes about 2.24% of all head and neck lesions with a mean age of occurrence of 35.84 years. […] AM has a predilection to occur in the third decade and in males and exhibits a marked propensity to occur in the mandibular posterior region. […] The trends in the distribution of any lesion show variations regionally as well as temporally and thus periodic and long-term presentation of their demographic data ensures more accurate and updated information that is accessible to clinicians or researchers.
#10 Ameloblastoma – Wikipedia
https://en.wikipedia.org/wiki/Ameloblastoma
People with African heritage have been shown to have a higher incidence compared to Caucasians, with the site often being in the midline of the mandible. The annual incidence rates per million for ameloblastomas are 1.96, 1.20, 0.18 and 0.44 for black males, black females, white males and white females respectively. Ameloblastomas account for about one percent of all oral tumors and about 18% of odontogenic tumors. Men and women are equally affected, though women average four years younger than men when tumors first occur, and tumors run larger in females.
#11 Ameloblastoma overview – wikidoc
https://www.wikidoc.org/index.php/Ameloblastoma_overview
The incidence of ameloblastoma is approximately 1.96, 1.20, 0.18, and 0.44 per 100,000 for black males, black females, white males, and white females respectively, worldwide. Ameloblastoma affects men and women equally. There is no racial predilection to the ameloblastoma. Ameloblastoma usually occur in middle age group i.e. 20-40 years; the median age at diagnosis is 39 years […] The incidence of ameloblastoma is approximately 1.96, 1.20, 0.18, and 0.44 per 100,000 for black males, black females, white males, and white females respectively worldwide. Ameloblastoma affects men and women equally. There is no racial predilection to the ameloblastoma. Ameloblastoma usually occur in middle age group i.e. 20-40 years; the median age at diagnosis is 39 years.
#12
https://journals.lww.com/jpat/fulltext/2014/18001/ameloblastoma_in_the_northeast_region_of_brazil__a.14.aspx
Ameloblastomas are benign tumors of the jaws with locally invasive capacity. […] The aim of this study was to review 112 cases of ameloblastoma seen over an 18-year period (1992-2009) at the Pernambuco Dental School, University of Pernambuco and at Federal University of Sergipe, in the northeast region of Brazil. […] The mean age of the patients at presentation was 35.1 16.8 years with a slight female preference. […] The peak prevalence was in the 11- to 20-year age group and declined with increasing age. […] Total 75 patients were black and 37 were white, for a 2:1 black: white ratio. […] The location of the ameloblastomas showed a marked predominance in the mandible (84.8%) and 69% of the cases presented with a multilocular radiographic appearance. […] Recurrence was observed in 13.3% of cases.
#13
https://journals.lww.com/jpat/fulltext/2014/18001/ameloblastoma_in_the_northeast_region_of_brazil__a.14.aspx
We propose that racial factors may have strong influence on the incidence of ameloblastomas in the northeast region of Brazil, since most people have African descent. […] Data related to gender, location, radiographic appearance, size, symptoms, clinicopathologic subtypes and recurrence were similar to previous studies conducted in various parts of the world.
#14 Ameloblastoma: Symptoms, Causes & Treatment
https://my.clevelandclinic.org/health/diseases/22143-ameloblastoma
Ameloblastomas are one of the most common benign jaw tumors, but theyâre still rare overall. Studies estimate that every year, only 1 in 1 million people is diagnosed with ameloblastoma. And only 2% of those people have malignant ameloblastoma. […] Anyone can develop ameloblastoma, but the condition is more common in people from ages 30 to 60. Diagnoses are more common in Africa and Asia. […] Most people treated for ameloblastomas will need life-long monitoring to check for recurrences. Ameloblastoma grows back after surgery in up to 20% of people. More than half of the time, tumors recur within the first five years after surgery. […] Seeking treatment for an ameloblastoma can prevent these worst-case scenarios from happening.
#15 Ameloblastoma of the Jaws: A Retrospective Analysis of 340 Cases in a Malaysian Population
https://repository.nih.gov.my/handle/123456789/1388
Purpose: Ameloblastoma of the human jaw is an uncommon but clinically significant odontogenic epithelial neoplasm. The aim was to analyze the clinicopathologic characteristics of ameloblastoma in a Malaysian population. […] Results: Three hundred forty cases of ameloblastoma were reviewed. These were from 197 male patients (57.9%) and 143 female patients (42.1%), with a male-to-female ratio of 1.4:1. A wide age range (7 to 85 years), mean onset age of 30.3 16.3 years, and peak incidence in the second decade of life were recorded. […] Conclusions: Because ameloblastoma subsets differ in their biologic behavior, the present data are significant as baseline references for clinicians and pathologists.
#16 Ameloblastoma – Symptoms and causes – Mayo Clinic
https://www.mayoclinic.org/diseases-conditions/ameloblastoma/symptoms-causes/syc-20351278
Ameloblastoma is a rare, noncancerous (benign) tumor that develops most often in the jaw near the molars. […] Though ameloblastoma is most often diagnosed in adults in their 30s through 60s, ameloblastoma can occur in children and young adults. […] Ameloblastomas are generally classified by type, but they can also be classified by cell type. […] The four main types include: […] Conventional ameloblastoma. This is the most common type and grows aggressively, usually in the lower jawbone, and approximately 10% recur after treatment. […] Unicystic ameloblastoma. This type is less aggressive, but typically occurs at a younger age. […] Peripheral ameloblastoma. This type is rare and affects the gums and oral tissue in the upper or lower jaw. […] Metastasizing ameloblastoma. This type is very rare and is defined by tumor cells that occur away from the primary site in the jaw. […] Rarely, ameloblastoma can become cancerous (malignant). […] Ameloblastoma may recur after treatment.
#17 Ameloblastomas: current aspects of the new WHO classification in an analysis of 136 cases | Surgical and Experimental Pathology | Full Text
https://surgexppathol.biomedcentral.com/articles/10.1186/s42047-019-0041-z
Ameloblastomas are neoplasms that have inspired great controversy and clinical interest; their incidence, radiographic features, treatment and behavior are still discussed quite often in the literature. […] There is no predilection for sex and its highest incidence is in the third and fourth decades of life. […] Ameloblastomas represent approximately 11 to 18% of all odontogenic tumors, being the second most common after odontomas. […] In our study, 52% of the patients were male. […] The majority of patients were male, with 71 men (52%) and 65 women (48%). […] The conventional ameloblastomas in this study represented the highest percentage of these tumors (71.3%), most of them diagnosed in the fourth decade of life (58.7%), with a slight preference for men and located mainly in the posterior region of the mandible (91.8%).
#18 Ameloblastomas: current aspects of the new WHO classification in an analysis of 136 cases | Surgical and Experimental Pathology | Full Text
https://surgexppathol.biomedcentral.com/articles/10.1186/s42047-019-0041-z
The diagnosis of unicystic ameloblastoma was confirmed in 37 cases, occurring mainly in young patients (75.6%), with a mean age in the third decade of life and predilection for the posterior region of the mandible (92%). […] The treatment of choice for most conventional ameloblastoma cases was segmental resection (45%), followed by curettage with cryotherapy (40%), and the remaining (15%) were treated with curettage only. […] The mean follow-up time was 10 years and 18 patients presented recurrences (13.2%), 16 with conventional ameloblastoma and 2 with unicystic tumors. […] The prognosis is usually favorable, although it may cause deformities. […] Relatively high relapse rates for this type of tumor remain a major challenge. […] Understanding the behavior of this tumor is essential to avoid local morbidity and increased rates of relapse.
#19 Pathology Outlines – Ameloblastoma
https://www.pathologyoutlines.com/topic/mandiblemaxillaameloblastoma.html
Epidemiology […] – Represents 1% of all jaw cysts and tumors […] – Most common odontogenic neoplasm […] – Incidence: 0.5 cases per million population […] – No sex predilection […] – Majority of ameloblastomas are conventional type, followed by unicystic, peripheral […] – Broad age range, narrowed somewhat by tumor type: […] – Ameloblastoma, conventional type: peak incidence in fourth to fifth decades of life […] – Ameloblastoma, unicystic type: peak incidence in second to third decades of life […] – Ameloblastoma, extraosseous / peripheral type: peak incidence in fifth to seventh decades of life
#20 Epidemiology – Medischola Tanzania
https://medischola.org/courses/dentistry/lessons/ameloblastoma/topics/epidemiology-33/
Ameloblastomas represent about 1% of all jaw tumors, but they are the second-most common odontogenic tumor. They are much more common in the lower jaw (80%) than in the upper jaw (20%), and more common in the posterior mandible as compared to the anterior. They are most common in patients aged between 20 to 40 years.
#21 Clinicopathological and Demographic Characteristics of 171 Cases of Ameloblastoma: A 40-Year Retrospective Institutional Study in Maharashtra – Global Journal of Medical Pharmaceutical and Biomedical Update
https://gjmpbu.org/clinicopathological-and-demographic-characteristics-of-171-cases-of-ameloblastoma-a-40-year-retrospective-institutional-study-in-maharashtra/
The observed predominance of AM (57.38%) among other OTs was also slightly higher than previous studies that recorded values of 45.72% and 53%. […] The majority of cases (65.34%) in our study occurred in the third to fifth decades. […] AM has displayed a marked propensity to occur in the mandibular jaw globally across multiple studies with nearly 90% of cases occurring in the mandible. […] The ratio of cases occurring in mandible to maxilla in our study was found to be 6.43:1, whereas the previous studies have found this ratio similar or even as high as 10:1. […] The demographic, radiographic, and histopathological data would contribute to updating the available information on AM on a national level.
#22 Maxillary Ameloblastoma: A Review With Clinical, Histological and Prognostic Data of a Rare Tumor | In Vivo
https://iv.iiarjournals.org/content/34/5/2249
Maxillary ameloblastomas are exceedingly rare with only sparse information on their epidemiological, histological and genetic characteristics. […] According to available data, maxillary ameloblastomas can occur in all ages but later than mandible ones, and everywhere within the maxillary region without necessarily having direct contact with the teeth. […] Ameloblastomas located in the maxillary region are rare compared to those arising in the mandible, the latter being five times more frequent. […] Indeed, maxillary ameloblastomas account for 15% of all ameloblastomas. […] The natural history, epidemiology, localization, histopathology and prognostic factors remain unclear since there are only a few case series referring exclusively to maxillary ameloblastomas. […] A wide range of ages has been reported for maxillary ameloblastoma, starting from early childhood, with a case of a six-year-old child being the younger patient reported until elderly people with a case of an 81-year-old male were reported. […] It is worth noting that maxillary ameloblastomas occur about 10 years later than those arising in the mandible, probably representing the lack of evident early symptoms, while no sex predilection is found.
#23
https://www.ijmbs.info/index.php/ijmbs/article/view/2609
Ameloblastoma is common benign epithelial tumor of odontogenic origin. […] The common characteristic of ameloblastoma is follicular and plexiform ameloblastoma with the most predilection location in mandible region and the peak of incidence in third decades of life. […] Radical treatment is more often used to reduce recurrence rates, whereas conservative measures are normally preserved in children and adolescent.
#24 Incidence and Overall Survival of Malignant Ameloblastoma | PLOS One
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0117789
Malignant ameloblastoma, comprising metastasizing ameloblastoma and ameloblastic carcinoma, represents 1.62.2% of all odontogenic tumors. […] Using the Surveillance, Epidemiology and End-Results (SEER) database, we have performed a population-based study to determine the incidence rate and the absolute survival of malignant ameloblastoma. […] The overall incidence rate of malignant ameloblastoma was 1.79 per 10 million person/year. […] The incidence rate was higher in males than females and also higher in black versus white population. […] To our best knowledge, we report the largest population-based series of malignant ameloblastoma. The incidence rate was 1.79 per 10 million person/year and the overall survival was 17.6 years. […] The Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute is a population-based cancer database covering approximately 28% of the United States (US) population and collects epidemiological information of patients with cancer.
#25 Incidence and Overall Survival of Malignant Ameloblastoma | PLOS One
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0117789
In this study, we have extracted the incidence rate and absolute survival from 293 malignant ameloblastoma cases reported in the SEER database. […] The overall incidence rate of malignant ameloblastoma was 1.79 per 10 million person/year (Table 2). […] The incidence rate was also significantly higher in the black population than in the white. […] Perusing the SEER data, our study demonstrated that the overall incidence rate of malignant ameloblastoma was 1.79 per 10 million persons per year with male and black population predominance.
#26 Incidence and overall survival of malignant ameloblastoma
https://researchonline.jcu.edu.au/41938/
Malignant ameloblastoma, comprising metastasizing ameloblastoma and ameloblastic carcinoma, represents 1.62.2% of all odontogenic tumors. […] Using the Surveillance, Epidemiology and End-Results (SEER) database, we have performed a population-based study to determine the incidence rate and the absolute survival of malignant ameloblastoma. […] The overall incidence rate of malignant ameloblastoma was 1.79 per 10 million person/year. […] The incidence rate was higher in males than females and also higher in black versus white population. […] The median overall survival was 17.6 years from the time of diagnosis and increasing age was associated with a statistically significant poorer survival. […] To our best knowledge, we report the largest population-based series of malignant ameloblastoma. The incidence rate was 1.79 per 10 million person/year and the overall survival was 17.6 years.
#27 Ameloblastoma RNA profiling uncovers a distinct non-coding RNA signature | Oncotarget
https://www.oncotarget.com/article/13889/text/
The step two validation in 35 histologically validated tumour samples and relevant controls with qPCR led to conclusion that five unique ncRNAs LINC340, SNORD116-25, SNORA11, SNORA21, and SNORA65 are highly associated to ameloblastoma. […] The features of ncRNA e.g. suitability for molecular detection and bioavailability in biofluids thus favour development of more sensitive PCR screenings on both puncture biopsies as well as liquid biopsies. […] The predictive ability of identified ncRNA thus extend beyond currently available protein markers, thus could be of use to monitor tumour growth and control this pathology to improve the quality of life of patients affected by this neoplasia.
#28 Ameloblastoma of the Mandible in a 16-Year-Old FemaleâCase Report
https://www.mdpi.com/1648-9144/60/1/66
Regarding the presented case, its particularity is represented by the late request for medical consultation, a direct consequence of the measures implemented to prevent and control the spread of COVID-19. Coronavirus disease 2019 (COVID-19) was accompanied by a series of measures that put pressure on health systems around the world. The available medical assistance capacity was affected by the conversion of medical units into COVID-19 care units, the deployment of doctors to care for patients with COVID-19, the limitation of the number of hospitalizations by increasing the hospitalization time until obtaining the result of the RT-PCR test and the decrease the degree of occupation of medical departments by isolating patients. Other notable changes that affected patients included the postponement of routine care, the use of telemedicine as a substitute for clinical consultation with a negative impact on the quality of care, the restriction of the activity of dental offices, triage activities. Also, the fear of viral contagion produced a reluctance of patients to request medical care. It is reported in various medical studies that these changes have led to diagnostic delays and poorer therapeutic results in a number of conditions. […] Periodic clinical and radiological follow-up are mandatory due to the high recurrence rate of ameloblastoma.
#29 Prevalence of Ameloblastoma in Sub-Saharan Africa: A Systematic Review and Meta-Analysis by Adetayo Aborisade, Dr Chizoba Okolo, Dr Olusegun Akinsanya, Dr Chika Oguchi, Dr Olusegun Alalade, Dr Adeniyi Oluwadaisi :: SSRN
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4876624
Ameloblastoma is the most common odontogenic tumor (OT) accounting for about 1- 3% of all tumors and tumor-like lesions of the head and neck region. […] Contrasting reports from documented studies have observed that the relative frequency of ameloblastomas is higher in the black population as compared to Caucasians. […] The pooled prevalence for Ameloblastoma was 12% (CI 95%: 9% – 15%). […] Prevalence was higher in Nigeria (13%, CI 95%: 10% – 17%) than in other sub-Saharan countries (9%, CI 95%: 6% – 14%). […] Significant gaps in data collection and overall knowledge about its epidemiology were identified, particularly about the population-based incidence of Ameloblastoma in sub-Saharan countries. […] Accurate estimates of the prevalence and incidence of Ameloblastoma are needed to plan for the health and social services that will be required to deal with this enigmatic lesion.