Materiały źródłowe

• #1 Benign peripheral nerve tumor – Symptoms and causes – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/peripheral-nerve-tumors-benign/symptoms-causes/syc-20368680

  Benign peripheral nerve tumors are tumors that form on peripheral nerves. The peripheral nerves link the brain and spinal cord to other parts of the body. These nerves control muscles that allow you to walk, blink, swallow, pick things up and do other activities. Benign tumors are not cancerous. […] Although most of these types of tumors are not cancerous, they can cause nerve damage and loss of muscle control. It’s important to see your healthcare professional if you have a lump or if you have pain, tingling, numbness or muscle weakness. […] The cause of benign peripheral nerve tumors usually isn’t known. Some are passed down in families. […] Risk factors may be different based on the type of benign peripheral nerve tumor. […] For neurofibromas, having the genetic condition known as neurofibromatosis type 1 (NF1) is a risk factor. NF1 can cause someone to have several neurofibromas. But most people who have neurofibromas don’t have NF1. […] People with NF1 are also at increased risk for developing a malignant peripheral nerve sheath tumor. Its important for them to check in often with a health care professional to monitor that risk. […] For schwannomas, having the gene that causes schwannomatosis is a risk factor.

• #1 Schwannoma – Symptoms, Causes, TreatmentsSecond Opinion IconGroup 9Group 49

  https://www.barrowneuro.org/condition/schwannoma/

  Schwannomas are rare, with less than 200,000 diagnosed cases yearly in the United States. However, they are the most common tumors of peripheral nerves in adults. […] The exact incidence of schwannomas in the general population is not clearly defined due to their rarity and the fact that they often remain asymptomatic and undiagnosed. […] The incidence rate of spinal schwannomas is not well documented. Still, it is considered to be lower than that of vestibular schwannomas. […] Schwannomas can occur at any age but are most commonly diagnosed in adults between 20 and 50. […] Most schwannomas are solitary and sporadic, although individuals with certain genetic conditions like NF2 are at a higher risk of developing multiple tumors. […] Given their benign nature, schwannomas often grow slowly and may not cause symptoms for many years. […] Overall, the survival rate for individuals with schwannomas is excellent since these tumors are benign.

• #1 Nerve Sheath Tumors: Definition & Types

  https://my.clevelandclinic.org/health/diseases/22526-nerve-sheath-tumors

  Benign nerve sheath tumors are relatively rare. Schwannomas are most common in people between the ages of 50 and 60. Neurofibromas most often occur in people between the ages of 20 and 40. Plexiform neurofibromas usually develop before age 5. […] Malignant peripheral nerve sheath tumors are extremely rare, affecting about 1 out of every 10 million people each year. […] Most nerve sheath tumors are noncancerous. Theyre treatable with surgery and rarely come back. If your tumor cant be completely removed surgically, youll require ongoing monitoring. […] The risk of nerve sheath tumors becoming cancerous is very low. The greatest risk is for people with NF1 who develop plexiform neurofibroma. Malignant peripheral nerve sheath tumors have a poor prognosis, especially if the tumor is larger than 2 inches. Fewer than half of people with this condition live five years after diagnosis.

• #1 Pathology Outlines – Schwannoma

  https://www.pathologyoutlines.com/topic/softtissueschwannoma.html

  Benign nerve sheath tumor arising from differentiated Schwann cells […] All ages can be affected […] More common in 30 – 60 years of age […] M = F […] 90% are sporadic, 3% with neurofibromatosis type 2, 2% with schwannomatosis, 5% with meningiomatosis with or without neurofibromatosis type 2 (StatPearls: Schwannoma [Accessed 10 November 2021])

• #1 Neurilemmoma (Schwannoma): Practice Essentials, Etiology, Epidemiology

  https://emedicine.medscape.com/article/1256405-overview

  Neurilemmoma is the most common neurogenic tumor, but precise prevalence figures have not been established. These tumors affect persons aged 20-50 years. No racial or sex predilection is recognized. Common locations for neurilemmomas are, in order of decreasing frequency, the head and neck, the flexor surfaces of the upper and lower extremities, and the trunk. […] Rare descriptions exist of malignant change in long-standing neurilemmomas. Malignant change is extremely rare in isolated lesions.

• #1 Structural Origin and Surgical Complications of Peripheral Schwannomas | Anticancer Research

  https://ar.iiarjournals.org/content/40/11/6563

  Schwannomas, also known as neurilemmomas, are benign peripheral nerve sheath tumors originating from Schwann cells. Schwannomas usually occur in the third to fifth decades of life, with no racial and gender differences. Common schwannomas are solitary (95%). However, some studies reported multiple tumors in the extremities and referred to those as schwannomatosis. Schwannomas located in the upper extremity account for 12.0-19.0% of cases, and in the lower extremity for 13.5-17.5%. Schwannomas constitute 8.0% of all soft tissue tumors. […] Post-operative complications of schwannomas have been reported in 1.5-80.0% of cases, with neurological deficits as one of the major complications. Correlation studies between locations and post-operative complications of schwannomas help predict the possibility of surgical complications in each schwannoma site. The schwannomas’ nerve of origin, locations, and surgical complications are essential information for the operative indications and prevention of post-operative complications. […] In this study, the most common site of schwannomas was the median nerve. Peripheral schwannomas can arise from both motor and sensory nerves. However, further investigations such as immunohistochemistry, electron microscopy, and electrophysiological studies are needed.

• #1 Benign peripheral nerve sheath tumors: an interdisciplinary diagnostic and therapeutic challenge

  https://pmc.ncbi.nlm.nih.gov/articles/PMC10439084/

  A benign peripheral nerve sheath tumor (bPNST) is a rare lesion associated with peripheral nerval structures. Symptoms may be heterogeneous, complicating diagnosis finding. […] Therefore, we analyzed patients treated for bPNST in our specialized institution with a primary focus on prior misdiagnosis and possible mistreatment. […] Eighty-five patients were included in the final analysis with schwannoma being the most prevalent histopathological diagnosis (schwannoma (75.3%, n=64), neurofibroma (12.9%, n=11), hybrid nerve sheath tumor (5.9%, n=5), and perineurioma (5.9%, n=5)). An incorrect primary diagnosis was detected in 44.7% (n=38), leading to suboptimal or insufficient treatment in these cases. […] For the first time, our data shows the quantity and impact of incorrect initial diagnosis in bPNST causing a delay in causative treatment or resulting in unnecessary or potentially harmful treatment.

• #1 Management of peripheral nerve sheath tumors: 17 years of experience at Toronto Western Hospital in: Journal of Neurosurgery Volume 128 Issue 4 (2018) Journals

  https://thejns.org/view/journals/j-neurosurg/128/4/article-p1226.xml

  A surgical series of 201 benign and malignant peripheral nerve sheath tumors (PNSTs) was assessed to characterize the anatomical and clinical presentation of tumors and identify predictors of neurological outcome, recurrence, and extent of resection. […] All surgically treated PNSTs from the Division of Neurosurgery at Toronto Western Hospital from 1993 to 2010 were reviewed retrospectively. Data were collected on patient demographics, clinical presentation, surgical technique, extent of resection, postoperative neurological outcomes, and recurrence. […] One hundred seventy-five patients with 201 tumors had adequate follow-up for analysis. There were 182 benign and 19 malignant PNSTs. Of the benign lesions, 133 were schwannomas, 21 of which were associated with a diagnosis of schwannomatosis. There were 49 neurofibromas, and 26 were associated with neurofibromatosis Type 1 (NF1). Patients presenting with schwannomas were significantly older than those with neurofibromas. Schwannomas were more readily resected than neurofibromas, with the extent of resection of the former influenced by tumor location. Patients with benign PNSTs typically presented with a painful mass and less frequently with motor deficits. The likelihood of worsened postoperative motor function was decreased in patients with fully resected tumors or preoperative deficits. Recurrence of schwannomas and neurofibromas were seen more frequently in patients diagnosed with NF3 and NF1, respectively. Subtotal resection was associated with the increased recurrence of all benign lesions. […] Outcomes following resection of benign PNSTs depend on tumor histopathology, tumor location, and genetic predisposition syndrome. Gross-total resection should be attempted for benign lesions where possible. The management of malignant PNSTs remains challenging, requiring a multimodal approach.

• #1 Hybrid peripheral nerve sheath tumors: report of five cases and detailed review of literature | BMC Cancer | Full Text

  https://bmccancer.biomedcentral.com/articles/10.1186/s12885-017-3350-1

  Hybrid PNSTs have been reported in all age groups but have been most commonly reported in young adults and so far have not demonstrated any gender predilection. […] Hybrid PNSTs are associated with certain tumor syndromes, and more than half of hybrid PNSTs with such associations are multiple. […] Over 70% patients with schwannomatosis have single or multiple hybrid neurofibroma/schwannoma tumors. […] Similarly, over 25% patients with Neurofibromatosis (NF) 2 and about 90% patients with NF1 have single or multiple hybrid neurofibroma/schwannoma tumors. […] Hybrid neurofibroma/perineurioma tumors occur most commonly in association with NF1. […] In conclusion, we are of the opinion that PNSTs with well-defined hybrid features are indeed distinct entities as demonstrated not only by their hybrid morphology, but also by their distinct hybrid IHC features. […] The status of hybrid PNSTs as distinct entities has been recognized by the WHO and included in the 4th edition of the WHO classification of tumors of soft tissue and bone.

• #1 Schwannoma – Overview – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/schwannoma/cdc-20352974

  A schwannoma is a type of nerve tumor of the nerve sheath. It’s the most common type of benign peripheral nerve tumor in adults. It can occur anywhere in your body, at any age. […] Monitoring. Your doctor may suggest observing your condition over time. Observation may include regular checkups and a CT or MRI scan every few months to see if your tumor is growing.

• #1

  https://www.aurorahealthcare.org/services/neuroscience/brain-skull-base-care/peripheral-nerve-tumors

  Although theyre rare, there are many types of peripheral nerve tumors. […] Peripheral nerve tumors are usually benign tumors that grow on the peripheral nerves the nerves that branch out from the brain and spine (central nervous system). […] Benign tumors are usually small and slow-growing. […] The most common types of peripheral nerve tumors in adults are schwannomas. […] Some peripheral nerve tumors called neurofibromas are associated with neurofibromatosis type 1 or neurofibromatosis type 2. […] A small percentage of neurofibromas and schwannomas can become malignant peripheral nerve sheath tumors (MPNSTs). […] Treatment depends on the location, size, type and growth rate of the tumor. […] For some benign tumors that are small, slow-growing and not likely to cause significant symptoms, well recommend ongoing observation. […] Surgery may be recommended for some benign tumors that are associated with important functions or may affect nearby organs or tissues. […] Malignant peripheral nerve sheath tumor treatment usually includes cancer surgery to remove as much of the tumor as possible.

• #1 Benign peripheral nerve tumor | Beacon Health System

  https://www.beaconhealthsystem.org/library/diseases-and-conditions/benign-peripheral-nerve-tumor?content_id=CON-20341913

  Risk factors may be different based on the type of benign peripheral nerve tumor. […] For neurofibromas, having the genetic condition known as neurofibromatosis type 1 (NF1) is a risk factor. NF1 can cause someone to have several neurofibromas. But most people who have neurofibromas don’t have NF1. […] People with NF1 are also at increased risk for developing a malignant peripheral nerve sheath tumor. Its important for them to check in often with a health care professional to monitor that risk. […] For schwannomas, having the gene that causes schwannomatosis is a risk factor.

• #1 Benign peripheral nerve tumor – Vejthani Hospital | JCI Accredited International Hospital in Bangkok, Thailand.

  https://www.vejthani.com/diseases-conditions/benign-peripheral-nerve-tumor/

  Peripheral nerve tumors can cause nerve damage and loss of muscle control. Therefore, it is critical to have a proper diagnosis when there are any strange lumps, pain, tingling or numbness, or muscular weakness. […] In most cases, peripheral nerve tumors are benign or non-cancerous. […] The majority of neurofibromas are not malignant. Approximately 5% to 10% develop malignant peripheral nerve sheath tumors, which are cancerous tumors. People with neurofibromatosis type 1 (NF1) are more likely to develop a malignant peripheral nerve sheath tumor. […] Some peripheral nerve tumors have an unknown cause. In some cases, it may be influenced by genetic alterations. The NF2 gene is linked to schwannomas, while the NF1 gene is linked to neurofibromas. These can be genetically handed down in families. […] Another benign peripheral nerve tumor is perineurioma. Although uncommon, it can develop from either inside or outside the nerve. When tumors outside a nerve impinge on it, they might cause issues.

• #1 Pathology Outlines – Malignant peripheral nerve sheath tumor (MPNST)

  https://www.pathologyoutlines.com/topic/softtissuempnst.html

  Epidemiology […] MPNST can occur in the following settings: Sporadic (approximately 50%) In neurofibromatosis type 1 (40 – 50%) In the setting of prior radiation therapy (10%) […] Plexiform neurofibroma is a common precursor lesion in patients with NF1 Patients with NF1 have an 8 – 13% lifetime risk of developing MPNST Plexiform neurofibromas are seen in approximately 50% of patients (Sarcoma 2017;2017:7429697) 10 – 15% of plexiform neurofibromas transform to MPNST (Hum Mutat 2008;29:E103) […] Other nerve sheath tumors (schwannoma, ganglioneuroma) may rarely give rise to secondary MPNST (Am J Surg Pathol 1994;18:882, Am J Surg Pathol 2001;25:13, Pathology 2015;47:595, Histopathology 1988;12:445)

• #1

  https://link.springer.com/article/10.1007/s10143-023-02107-z

  A misdiagnosis occurred, if the final diagnosis was inconsistent with the diagnosis which was set up by the doctor who treated the patient at first. […] Inappropriate surgical treatment was present, if the patient was surgically treated not due to the bPNST, but because of an accompanying disc prolapse or a nerve entrapment syndrome, for example, without relieve of the symptoms. […] Our study presents data on rates of initial misdiagnosis and mistreatment in patients with bPNST. […] In our series, 44.7% of patients with sporadic bPNST presenting to our specialized institution had an initial misdiagnosis that led to inappropriate surgical treatment in most of these patients (71.1%). […] Treatment should be performed only at a specialized center.

• #1 Benign peripheral nerve sheath tumors: an interdisciplinary diagnostic and therapeutic challenge

  https://pmc.ncbi.nlm.nih.gov/articles/PMC10439084/

  We aimed to evaluate the rate of primary misdiagnosis and mistreatment in patients suffering from deep-seated bPNSTs. Furthermore, we aimed to identify causative factors for mistreatment. […] An initial incorrect diagnosis was made in 44.7% of patients. […] Misdiagnosis and mistreatment showed a significant correlation with the treating specialist. […] Furthermore, patients with neurological deficits were misdiagnosed and mistreated significantly more often than patients without neurological deficits. […] Our study presents data on rates of initial misdiagnosis and mistreatment in patients with bPNST. In our series, 44.7% of patients with sporadic bPNST presenting to our specialized institution had an initial misdiagnosis that led to inappropriate surgical treatment in most of these patients (71.1%).

• #1 Collection of Rare Peripheral Nerve Tumors—Insights from the German Registry

  https://www.mdpi.com/2072-6694/16/14/2599

  The most common peripheral nerve tumors are of a benign nature and include schwannoma or neurofibroma. […] A definitive preoperative differentiation between benign peripheral nerve tumors and rare intrinsic and extrinsic tumors is often not possible. Clinical examination and subtle imaging clues can at least indicate the possibility of a rare entity. […] The multicentric peripheral nerve tumor registry provides multicentric data on rare tumorous lesions for the first time. This article aims to provide an overview of the clinical, imaging, and pathological features of uncommon lesions associated with peripheral nerves, emphasizing characteristics that set them apart from common peripheral nerve tumors like schwannoma and neurofibroma. […] In our surgical series, 19% of lesions were considered “rare” and associated with peripheral nerves. If we exclude the intrinsic rare PNTs, our cohort’s percentage of non-neural lesions is 5%. From this, it can be inferred that these rare tumors occur more frequently than previously thought. However, there are currently no data available on their incidences.

• #1 PERIPHERAL NERVE TUMORS – Dr Prem Pillay

  https://singaporebrain.org/en/nerves/peripheral-nerve-tumors/

  MPNSTs are aggressive soft-tissue sarcomas accounting for about 10% or slightly more of all peripheral nerve sheath tumors. […] Imaging studies are central in delineating the location and extent of the tumor. […] In asymptomatic, slowly growing, small benign peripheral nerve tumors (usually a few mm in size) a watch-and-wait approach (also called monitoring) may be considered if they do not threaten function. […] Micro-surgical resection remains the mainstay of therapy for most peripheral nerve tumors, both benign and malignant. […] Adjuvant Radiotherapy: Often recommended for malignant peripheral nerve sheath tumors with larger lesion sizes or aggressive histological features. […] MPNSTs, unfortunately, do not respond robustly to conventional chemotherapy, though anthracycline-based regimens may be tried in inoperable or metastatic settings.

• #1 Quantitative FDG-PET is more accurate than CT size at differentiating malignant from benign peripheral nerve tumors | Journal of Nuclear Medicine

  https://jnm.snmjournals.org/content/49/supplement_1/41P.3

  Objectives: Differentiating malignant [malignant peripheral nerve sheath tumors (MPNST)] from benign (neurofibromas schwannomas) peripheral nerve tumors (PNT) is often difficult. Correct pre-treatment classification is critical for the optimal management. The aim of this study was to prospectively evaluate whether F18-fluorodeoxyglucose positron emission tomography (FDG-PET) or computed tomography (CT) could distinguish between benign and malignant PNT. […] Conclusions: Quantitative FDG-PET was significantly more accurate than CT size at differentiating malignant from benign peripheral nerve tumors. FDG-PET should be considered as a modality to make treatment related decisions in patients with PNT.

• #1 When biopsy goes wrong: a case series of misdiagnoses and complications from biopsies of masses of unknown origin potentially originating from a peripheral nerve in: Journal of Neurosurgery Volume 140 Issue 2 (2023) Journals

  https://thejns.org/view/journals/j-neurosurg/140/2/article-p480.xml

  Biopsies of peripheral nerve tumors (PNTs) are often used to plan an efficient treatment strategy. However, performing a biopsy is controversial when the mass is likely to be a benign PNT (BPNT). The aim of this study was to evaluate the side effects of biopsies in patients with potential PNTs. […] Biopsies of PNTs are controversial and may result in misdiagnosis, neuropathic pain, or neurological deficit due to axonal damage, and they may also hinder microsurgical resection when if performed when not indicated. Indications for biopsy of an MUOPON must be carefully considered, especially if BPNT is a possible diagnosis. […] The initial diagnosis obtained by biopsy differed from the final histopathological diagnosis in all patients, of whom 21 (87.5%) had BPNTs, 2 (8.3%) malignant peripheral nerve sheath tumors, and 1 (4.2%) an ancient schwannoma.

• #1 Peripheral nerve sheath tumor | Radiology Reference Article | Radiopaedia.org

  https://radiopaedia.org/articles/peripheral-nerve-sheath-tumour-2?lang=us

  Peripheral nerve sheath tumors (PNSTs) are a group of primary neurogenic tumors that arise from nerve sheaths outside of the central nervous system. The vast majority are benign, however, malignant transformation is seen particularly in large tumors and those associated with neurofibromatosis type 1 (NF1). […] Symptoms of benign peripheral nerve sheath tumors are non-specific and include sensory and/or motor deficits, isolated pain, painful mass (i.e. positive Tinel sign), asymptomatic mass or may be incidental. […] Surgical resection is the treatment of choice, not only for diagnostic confirmation (i.e. histopathology) and also with curative intent. […] Pre-surgical biopsy of peripheral nerve sheath tumors (usually an ultrasound-guided core biopsy) is typically reserved for lesions with indeterminate or malignant clinical and/or radiological features; the risk of biopsy (e.g. new/worsening neuropathic pain or sensory/motor impairment) outweighs the benefit of biopsy in suspected benign peripheral nerve sheath tumors.

• #1 Association between benign and malignant peripheral nerve sheath tumors in NF1 – PubMed

  https://pubmed.ncbi.nlm.nih.gov/16043787/

  People with neurofibromatosis type 1 (NF1) have a 10% lifetime risk of developing a malignant peripheral nerve sheath tumor (MPNST). […] The observation that malignant peripheral nerve sheath tumors are strongly associated with internal plexiform neurofibromas suggests that patients with neurofibromatosis type 1 with these benign tumors warrant increased surveillance for malignancy.

• #1 Different Pathology of Peripheral Nerve Sheath Tumor in Neurofibromatosis Type 1: 3 Cases

  https://www.thenerve.net/DOIx.php?id=10.21129/nerve.2021.7.2.92

  Neurofibromatosis type 1 (NF1) is an autosomal-dominant hereditary disease with a prevalence of about 1 in 3000. […] Because NF1 patients are at higher risk of malignancy, which is the most common cause of death, surgical resection and pathologic confirmation are very important to the treatment of symptomatic or growing tumors in NF1 patients. […] The incidence of MPNST is approximately 0.001% in the general population. The recurrence rate is approximately 40% to 65%, and metastasis is found in 16% to 39% of patients. […] NF1 patients are at high risk of neoplastic disease; the overall risk of cancer in NF1 patients is 2.7 times higher and the risk of malignancy in 50-year-olds is approximately 20%. […] Therefore, appropriate surveillance is required for NF1 patients. […] Detection and treatment of atypical neurofibroma are important in NF1 patients. […] Our experience suggests that MRI findings are important and useful for the differentiation of three types PNSTs. […] Further study and specific management plans are needed for PNSTs in NF1.

• #1

  https://continentalhospitals.com/diseases/benign-peripheral-nerve-tumor/

  By understanding the potential causes of benign peripheral nerve tumors, healthcare professionals can better assess patients’ risk factors and provide appropriate care and treatment options. […] Regular medical check-ups and screenings become increasingly important as individuals reach this age range. […] It is worth noting that while these risk factors may increase the likelihood of developing benign peripheral nerve tumors, they do not guarantee their occurrence. […] By understanding these risk factors, individuals can take proactive steps towards early detection, proper diagnosis, and timely treatment if necessary. […] Accurate and timely diagnosis is crucial when it comes to benign peripheral nerve tumors. […] Regular check-ups with healthcare professionals are essential for early detection and intervention. […] In conclusion, prevention plays a vital role in managing benign peripheral nerve tumors. […] Regular communication with healthcare professionals can provide valuable guidance on managing individual risks and maintaining overall well-being.

• #1 Nerve Tumors | Brain Institute | OHSU

  https://www.ohsu.edu/brain-institute/nerve-tumors

  The OHSU Nerve Center offers the expertise to precisely diagnose and treat peripheral nerve tumors. Specialty care and early diagnosis can be especially important for nerve tumors, which can range from simple to complex. […] Most are benign. Even some noncancerous tumors need treatment, though, because they can press on nerves and cause pain, nerve damage and/or loss of function. […] Early diagnosis is important for nerve tumors. Malignant peripheral nerve tumors are rare but require aggressive treatment for the best possible outcome.

• #1 SEER Inquiry System – Question 20071093 Details

  https://seer.cancer.gov/seer-inquiry/inquiry-detail/20071093/

  Benign and borderline tumors of the peripheral nerves (C47_), including peripheral nerves along the spinal cord, are not reportable. […] Please note: spinal schwannomas arising in the nerve root or spinal dura are reportable.

• #1 Benign nerve tumours in the upper limb: a registry-based study of symptoms and surgical outcome | Scientific Reports

  https://www.nature.com/articles/s41598-023-38184-9

  Surgery for benign nerve tumours is performed for pathoanatomical diagnosis and symptomatic relief, but might cause residual problems. […] In total, 206 cases surgically treated for a benign peripheral nerve tumour 20102019 registered in the Swedish Quality Registry for Hand Surgery (HAKIR; response rates 2234%) were analysed. […] We conclude that surgery for benign peripheral nerve tumours provides good symptomatic relief with low risk for residual problems. […] The mean incidence of Schwannomas in the upper limb requiring surgical treatment has been approximated to 0.62 per 100 000 inhabitants and year. […] Due to the rarity of benign peripheral nerve tumours, the number of large descriptive and comparative studies are limited. […] The aim of this study was to assess patient-reported symptoms and disability before and after surgical intervention at a national level.

• #1 PERIPHERAL NERVE TUMORS – Dr Prem Pillay

  https://singaporebrain.org/en/nerves/peripheral-nerve-tumors/

  Research into molecular pathways involved in PNSTs, especially MPNSTs, has propelled the exploration of targeted agents. […] Peripheral nerve tumors, encompassing benign entities such as schwannomas and neurofibromas and malignant variants like MPNSTs, represent a diverse group requiring careful workup and multidisciplinary treatment. Accurate diagnosis via imaging and biopsy, alongside precision surgical techniques, can often lead to remission in benign lesions and offer the best chance for disease control in malignant ones.

• #2 Benign peripheral nerve tumor | Health Library | Memorial Health System

  https://www.mhsystem.org/health-library/con-20341913/

  Benign peripheral nerve tumors are tumors that form on peripheral nerves. The peripheral nerves link the brain and spinal cord to other parts of the body. These nerves control muscles that allow you to walk, blink, swallow, pick things up and do other activities. Benign tumors are not cancerous. […] Although most of these types of tumors are not cancerous, they can cause nerve damage and loss of muscle control. Its important to see your healthcare professional if you have a lump or if you have pain, tingling, numbness or muscle weakness. […] The cause of benign peripheral nerve tumors usually isnt known. Some are passed down in families. […] Risk factors may be different based on the type of benign peripheral nerve tumor. […] For neurofibromas, having the genetic condition known as neurofibromatosis type 1 (NF1) is a risk factor. NF1 can cause someone to have several neurofibromas. But most people who have neurofibromas dont have NF1. […] People with NF1 are also at increased risk for developing a malignant peripheral nerve sheath tumor. Its important for them to check in often with a health care professional to monitor that risk. […] For schwannomas, having the gene that causes schwannomatosis is a risk factor.

• #2 Schwannoma – Symptoms, Causes, TreatmentsSecond Opinion IconGroup 9Group 49

  https://www.barrowneuro.org/condition/schwannoma/

  Schwannomas are rare, with less than 200,000 diagnosed cases yearly in the United States. However, they are the most common tumors of peripheral nerves in adults. […] The exact incidence of schwannomas in the general population is not clearly defined due to their rarity and the fact that they often remain asymptomatic and undiagnosed. […] The incidence rate of spinal schwannomas is not well documented. Still, it is considered to be lower than that of vestibular schwannomas. […] Schwannomas can occur at any age but are most commonly diagnosed in adults between 20 and 50. […] Most schwannomas are solitary and sporadic, although individuals with certain genetic conditions like NF2 are at a higher risk of developing multiple tumors. […] Given their benign nature, schwannomas often grow slowly and may not cause symptoms for many years. […] Overall, the survival rate for individuals with schwannomas is excellent since these tumors are benign.

• #2 Nerve Sheath Tumors: Definition & Types

  https://my.clevelandclinic.org/health/diseases/22526-nerve-sheath-tumors

  Benign nerve sheath tumors are relatively rare. Schwannomas are most common in people between the ages of 50 and 60. Neurofibromas most often occur in people between the ages of 20 and 40. Plexiform neurofibromas usually develop before age 5. […] Malignant peripheral nerve sheath tumors are extremely rare, affecting about 1 out of every 10 million people each year. […] Most nerve sheath tumors are noncancerous. Theyre treatable with surgery and rarely come back. If your tumor cant be completely removed surgically, youll require ongoing monitoring. […] The risk of nerve sheath tumors becoming cancerous is very low. The greatest risk is for people with NF1 who develop plexiform neurofibroma. Malignant peripheral nerve sheath tumors have a poor prognosis, especially if the tumor is larger than 2 inches. Fewer than half of people with this condition live five years after diagnosis.

• #2 Neurilemmoma (Schwannoma): Practice Essentials, Etiology, Epidemiology

  https://emedicine.medscape.com/article/1256405-overview

  Neurilemmoma is the most common neurogenic tumor, but precise prevalence figures have not been established. These tumors affect persons aged 20-50 years. No racial or sex predilection is recognized. Common locations for neurilemmomas are, in order of decreasing frequency, the head and neck, the flexor surfaces of the upper and lower extremities, and the trunk. […] Rare descriptions exist of malignant change in long-standing neurilemmomas. Malignant change is extremely rare in isolated lesions.

• #2 Case Report of Schwannomas: Benign Tumour of the Peripheral Nerve Sheath – European Medical Journal

  https://www.emjreviews.com/neurology/article/case-report-of-schwannomas-benign-tumour-of-the-peripheral-nerve-sheath/

  Schwannomas, also known as neurilemmomas, are benign peripheral nerve sheath tumours arising from the Schwann cells surrounding the nerve. Incidence of peripheral nerve sheath benign tumours occurring in the lower extremities is rare (110%). […] A solitary schwannoma arising from the tibial nerve is more common than from the sural nerve, which is reported to be a rare occurrence. […] Despite its rare occurrence, schwannoma should always be included in the differential diagnosis. […] Schwannomas or neurilemmomas are well-encapsulated, lobulated lesions without metastatic potential, particularly if they are located in the extremities. […] The aim of treatment is total excision of the lesion without causing nerve damage that may lead to sensorimotor deficit. […] This report focusses on the early diagnosis of schwannoma by performing an MRI of the lower extremities.

• #2 Benign peripheral nerve sheath tumors: an interdisciplinary diagnostic and therapeutic challenge

  https://pmc.ncbi.nlm.nih.gov/articles/PMC10439084/

  A benign peripheral nerve sheath tumor (bPNST) is a rare lesion associated with peripheral nerval structures. Symptoms may be heterogeneous, complicating diagnosis finding. […] Therefore, we analyzed patients treated for bPNST in our specialized institution with a primary focus on prior misdiagnosis and possible mistreatment. […] Eighty-five patients were included in the final analysis with schwannoma being the most prevalent histopathological diagnosis (schwannoma (75.3%, n=64), neurofibroma (12.9%, n=11), hybrid nerve sheath tumor (5.9%, n=5), and perineurioma (5.9%, n=5)). An incorrect primary diagnosis was detected in 44.7% (n=38), leading to suboptimal or insufficient treatment in these cases. […] For the first time, our data shows the quantity and impact of incorrect initial diagnosis in bPNST causing a delay in causative treatment or resulting in unnecessary or potentially harmful treatment.

• #2 Collection of Rare Peripheral Nerve Tumors—Insights from the German Registry

  https://www.mdpi.com/2072-6694/16/14/2599

  The most common peripheral nerve tumors are of a benign nature and include schwannoma or neurofibroma. […] A definitive preoperative differentiation between benign peripheral nerve tumors and rare intrinsic and extrinsic tumors is often not possible. Clinical examination and subtle imaging clues can at least indicate the possibility of a rare entity. […] The multicentric peripheral nerve tumor registry provides multicentric data on rare tumorous lesions for the first time. This article aims to provide an overview of the clinical, imaging, and pathological features of uncommon lesions associated with peripheral nerves, emphasizing characteristics that set them apart from common peripheral nerve tumors like schwannoma and neurofibroma. […] In our surgical series, 19% of lesions were considered “rare” and associated with peripheral nerves. If we exclude the intrinsic rare PNTs, our cohort’s percentage of non-neural lesions is 5%. From this, it can be inferred that these rare tumors occur more frequently than previously thought. However, there are currently no data available on their incidences.

• #2 Management of peripheral nerve sheath tumors: 17 years of experience at Toronto Western Hospital in: Journal of Neurosurgery Volume 128 Issue 4 (2018) Journals

  https://thejns.org/view/journals/j-neurosurg/128/4/article-p1226.xml

  A surgical series of 201 benign and malignant peripheral nerve sheath tumors (PNSTs) was assessed to characterize the anatomical and clinical presentation of tumors and identify predictors of neurological outcome, recurrence, and extent of resection. […] All surgically treated PNSTs from the Division of Neurosurgery at Toronto Western Hospital from 1993 to 2010 were reviewed retrospectively. Data were collected on patient demographics, clinical presentation, surgical technique, extent of resection, postoperative neurological outcomes, and recurrence. […] One hundred seventy-five patients with 201 tumors had adequate follow-up for analysis. There were 182 benign and 19 malignant PNSTs. Of the benign lesions, 133 were schwannomas, 21 of which were associated with a diagnosis of schwannomatosis. There were 49 neurofibromas, and 26 were associated with neurofibromatosis Type 1 (NF1). Patients presenting with schwannomas were significantly older than those with neurofibromas. Schwannomas were more readily resected than neurofibromas, with the extent of resection of the former influenced by tumor location. Patients with benign PNSTs typically presented with a painful mass and less frequently with motor deficits. The likelihood of worsened postoperative motor function was decreased in patients with fully resected tumors or preoperative deficits. Recurrence of schwannomas and neurofibromas were seen more frequently in patients diagnosed with NF3 and NF1, respectively. Subtotal resection was associated with the increased recurrence of all benign lesions. […] Outcomes following resection of benign PNSTs depend on tumor histopathology, tumor location, and genetic predisposition syndrome. Gross-total resection should be attempted for benign lesions where possible. The management of malignant PNSTs remains challenging, requiring a multimodal approach.

• #2 Peripheral nerve sheath tumor | Radiology Reference Article | Radiopaedia.org

  https://radiopaedia.org/articles/peripheral-nerve-sheath-tumour-2?lang=us

  Peripheral nerve sheath tumors (PNSTs) are a group of primary neurogenic tumors that arise from nerve sheaths outside of the central nervous system. The vast majority are benign, however, malignant transformation is seen particularly in large tumors and those associated with neurofibromatosis type 1 (NF1). […] Symptoms of benign peripheral nerve sheath tumors are non-specific and include sensory and/or motor deficits, isolated pain, painful mass (i.e. positive Tinel sign), asymptomatic mass or may be incidental. […] Surgical resection is the treatment of choice, not only for diagnostic confirmation (i.e. histopathology) and also with curative intent. […] Pre-surgical biopsy of peripheral nerve sheath tumors (usually an ultrasound-guided core biopsy) is typically reserved for lesions with indeterminate or malignant clinical and/or radiological features; the risk of biopsy (e.g. new/worsening neuropathic pain or sensory/motor impairment) outweighs the benefit of biopsy in suspected benign peripheral nerve sheath tumors.

• #2 Mayo Clinic Health Library – Benign peripheral nerve tumor | Swiss Medical Network

  https://www.swissmedical.net/fr/healtcare-library/con-20341913

  People with NF1 are also at increased risk for developing a malignant peripheral nerve sheath tumor. It’s important for them to check in often with a health care professional to monitor that risk. […] Treatment of peripheral nerve tumors involves either surgical removal or watching the tumor for changes. If there’s a low chance that the tumor may become cancerous and if it isn’t causing symptoms, you might not need surgery. […] Your healthcare professional also might recommend observation if your tumor is in a place that makes it hard to remove. Observation includes regular checkups and imaging tests to see if the tumor is growing.

• #2 PERIPHERAL NERVE TUMORS – Dr Prem Pillay

  https://singaporebrain.org/en/nerves/peripheral-nerve-tumors/

  Peripheral nerve tumors are a heterogeneous group of neoplasms that arise from or affect nerves outside the brain and spinal cord. According to the 2021 WHO classification of the Central Nervous System (CNS), peripheral nerve sheath tumors (PNSTs) comprise a set of unique entities each with specific clinical, anatomical, histological, and molecular features. Broadly, PNSTs can be subdivided into benign and malignant forms, often reflecting differences in their behavior, prognosis, and recommended treatments. […] Patients with a peripheral nerve schwannoma may need to have screening of other nerves with MRI of the whole spine and Brain with gadolinium contrast to rule out multiple nerve tumors at other locations. […] Plexiform neurofibromas can transform into malignant peripheral nerve sheath tumors (MPNSTs) and therefore warrant close monitoring.

• #2 Schwannoma – Overview – Mayo Clinic

  https://www.mayoclinic.org/diseases-conditions/schwannoma/cdc-20352974

  A schwannoma is a type of nerve tumor of the nerve sheath. It’s the most common type of benign peripheral nerve tumor in adults. It can occur anywhere in your body, at any age. […] Monitoring. Your doctor may suggest observing your condition over time. Observation may include regular checkups and a CT or MRI scan every few months to see if your tumor is growing.

• #2 Pathology Outlines – Malignant peripheral nerve sheath tumor (MPNST)

  https://www.pathologyoutlines.com/topic/softtissuempnst.html

  Epidemiology […] MPNST can occur in the following settings: Sporadic (approximately 50%) In neurofibromatosis type 1 (40 – 50%) In the setting of prior radiation therapy (10%) […] Plexiform neurofibroma is a common precursor lesion in patients with NF1 Patients with NF1 have an 8 – 13% lifetime risk of developing MPNST Plexiform neurofibromas are seen in approximately 50% of patients (Sarcoma 2017;2017:7429697) 10 – 15% of plexiform neurofibromas transform to MPNST (Hum Mutat 2008;29:E103) […] Other nerve sheath tumors (schwannoma, ganglioneuroma) may rarely give rise to secondary MPNST (Am J Surg Pathol 1994;18:882, Am J Surg Pathol 2001;25:13, Pathology 2015;47:595, Histopathology 1988;12:445)

• #2 Surgical outcome of isolated benign peripheral nerve sheath tumors without neurofibromatosis | Egyptian Journal of Neurosurgery | Full Text

  https://ejns.springeropen.com/articles/10.1186/s41984-024-00297-2

  Benign peripheral nerve sheath tumors (BPNSTs) include schwannomas and neurofibromas. […] About 10% of soft tissue sarcomas are malignant peripheral nerve sheath tumors (MPNSTs), which are invasive and aggressive tumors. […] Malignant transformation of schwannomas is rare. […] Surgical resection remains the treatment of choice of BPNSTs because they may cause neural compromise, rapid growth, and pressure they apply to nearby structures. […] In asymptomatic cases, observation is accepted because the benign nature of the tumor. […] However, to diagnose a symptomatic PNSTs we depend on clinical examination, ultrasound, and MRI scan. […] There is no studies that showed the surgical outcomes after excision of isolated BPNSTs without neurofibromatosis, especially in long follow up period.

• #2 Association between benign and malignant peripheral nerve sheath tumors in NF1 – PubMed

  https://pubmed.ncbi.nlm.nih.gov/16043787/

  People with neurofibromatosis type 1 (NF1) have a 10% lifetime risk of developing a malignant peripheral nerve sheath tumor (MPNST). […] The observation that malignant peripheral nerve sheath tumors are strongly associated with internal plexiform neurofibromas suggests that patients with neurofibromatosis type 1 with these benign tumors warrant increased surveillance for malignancy.

• #2

  https://link.springer.com/article/10.1007/s10143-023-02107-z

  A benign peripheral nerve sheath tumor (bPNST) is a rare lesion associated with peripheral nerval structures. […] Therefore, we analyzed patients treated for bPNST in our specialized institution with a primary focus on prior misdiagnosis and possible mistreatment. […] An incorrect primary diagnosis was detected in 44.7% (n=38), leading to suboptimal or insufficient treatment in these cases. […] For the first time, our data shows the quantity and impact of incorrect initial diagnosis in bPNST causing a delay in causative treatment or resulting in unnecessary or potentially harmful treatment. […] We aimed to evaluate the rate of primary misdiagnosis and mistreatment in patients suffering from deep-seated bPNSTs. […] Misdiagnosis occurred if the final diagnosis was inconsistent with the diagnosis which was set up by the doctor who treated the patient at first.

• #2

  https://link.springer.com/article/10.1007/s10143-023-02107-z

  A misdiagnosis occurred, if the final diagnosis was inconsistent with the diagnosis which was set up by the doctor who treated the patient at first. […] Inappropriate surgical treatment was present, if the patient was surgically treated not due to the bPNST, but because of an accompanying disc prolapse or a nerve entrapment syndrome, for example, without relieve of the symptoms. […] Our study presents data on rates of initial misdiagnosis and mistreatment in patients with bPNST. […] In our series, 44.7% of patients with sporadic bPNST presenting to our specialized institution had an initial misdiagnosis that led to inappropriate surgical treatment in most of these patients (71.1%). […] Treatment should be performed only at a specialized center.

• #2 Benign peripheral nerve sheath tumors: an interdisciplinary diagnostic and therapeutic challenge

  https://pmc.ncbi.nlm.nih.gov/articles/PMC10439084/

  We aimed to evaluate the rate of primary misdiagnosis and mistreatment in patients suffering from deep-seated bPNSTs. Furthermore, we aimed to identify causative factors for mistreatment. […] An initial incorrect diagnosis was made in 44.7% of patients. […] Misdiagnosis and mistreatment showed a significant correlation with the treating specialist. […] Furthermore, patients with neurological deficits were misdiagnosed and mistreated significantly more often than patients without neurological deficits. […] Our study presents data on rates of initial misdiagnosis and mistreatment in patients with bPNST. In our series, 44.7% of patients with sporadic bPNST presenting to our specialized institution had an initial misdiagnosis that led to inappropriate surgical treatment in most of these patients (71.1%).

• #2 18F-FDG PET/CT Imaging Features of Benign Schwannomas | Journal of Nuclear Medicine

  https://jnm.snmjournals.org/content/60/supplement_1/2053

  Schwannomas are the most common benign peripheral nerve sheath tumor (BPNST). […] The primary aim of this study was to examine the 18F-FDG PET/CT imaging features of biopsy-proven schwannomas, noting multiple characteristics, including size, presence of calcifications, SUVmax, metabolic tumor volume (MTV), and total lesion glycolysis (TLG). […] Benign schwannomas may be large and demonstrate intense heterogeneous FDG activity, mimicking MPNSTs on F-FDG PET/CT. A significant proportion exhibit FDG activity above levels previously thought to be useful in differentiating BPNSTs from MPNSTs.

• #2 When biopsy goes wrong: a case series of misdiagnoses and complications from biopsies of masses of unknown origin potentially originating from a peripheral nerve in: Journal of Neurosurgery Volume 140 Issue 2 (2023) Journals

  https://thejns.org/view/journals/j-neurosurg/140/2/article-p480.xml

  Biopsies of peripheral nerve tumors (PNTs) are often used to plan an efficient treatment strategy. However, performing a biopsy is controversial when the mass is likely to be a benign PNT (BPNT). The aim of this study was to evaluate the side effects of biopsies in patients with potential PNTs. […] Biopsies of PNTs are controversial and may result in misdiagnosis, neuropathic pain, or neurological deficit due to axonal damage, and they may also hinder microsurgical resection when if performed when not indicated. Indications for biopsy of an MUOPON must be carefully considered, especially if BPNT is a possible diagnosis. […] The initial diagnosis obtained by biopsy differed from the final histopathological diagnosis in all patients, of whom 21 (87.5%) had BPNTs, 2 (8.3%) malignant peripheral nerve sheath tumors, and 1 (4.2%) an ancient schwannoma.

• #2 Different Pathology of Peripheral Nerve Sheath Tumor in Neurofibromatosis Type 1: 3 Cases

  https://www.thenerve.net/DOIx.php?id=10.21129/nerve.2021.7.2.92

  Neurofibromatosis type 1 (NF1) is an autosomal-dominant hereditary disease with a prevalence of about 1 in 3000. […] Because NF1 patients are at higher risk of malignancy, which is the most common cause of death, surgical resection and pathologic confirmation are very important to the treatment of symptomatic or growing tumors in NF1 patients. […] The incidence of MPNST is approximately 0.001% in the general population. The recurrence rate is approximately 40% to 65%, and metastasis is found in 16% to 39% of patients. […] NF1 patients are at high risk of neoplastic disease; the overall risk of cancer in NF1 patients is 2.7 times higher and the risk of malignancy in 50-year-olds is approximately 20%. […] Therefore, appropriate surveillance is required for NF1 patients. […] Detection and treatment of atypical neurofibroma are important in NF1 patients. […] Our experience suggests that MRI findings are important and useful for the differentiation of three types PNSTs. […] Further study and specific management plans are needed for PNSTs in NF1.

• #2 Benign peripheral nerve tumor | Beacon Health System

  https://www.beaconhealthsystem.org/library/diseases-and-conditions/benign-peripheral-nerve-tumor?content_id=CON-20341913

  Risk factors may be different based on the type of benign peripheral nerve tumor. […] For neurofibromas, having the genetic condition known as neurofibromatosis type 1 (NF1) is a risk factor. NF1 can cause someone to have several neurofibromas. But most people who have neurofibromas don’t have NF1. […] People with NF1 are also at increased risk for developing a malignant peripheral nerve sheath tumor. Its important for them to check in often with a health care professional to monitor that risk. […] For schwannomas, having the gene that causes schwannomatosis is a risk factor.

• #2 A giant posterior mediastinal malignant peripheral nerve sheath tumor and benign neurofibroma in body surface: a case report | BMC Surgery | Full Text

  https://bmcsurg.biomedcentral.com/articles/10.1186/s12893-021-01122-5

  The significant difference between Ki67 expression in both tumor (1% of neurofibroma vs. 30% of nerve sheath tumor) indicated the dramatic cell proliferation. […] MPNST is a rare neoplasm of the peripheral nervous system. Most of the tumors occur in young and middle-aged men, and most of them occur in limbs, scalp and neck. […] Atypical neurofibroma (ANF), with pathologically increased variable cellularity, cytological atypia and fascicular growth patterns, was regarded as precursor lesions for MPNST. […] Taken together, the appearance of neurofibroma should draw particular attention to the possibility of developing MPNST. Once NF1 is diagnosed, more careful imaging examinations should be carried out and needle biopsy is a more confirmative approach if possible.

• #2 Peripheral nerve tumors // Middlesex Health

  https://middlesexhealth.org/learning-center/diseases-and-conditions/peripheral-nerve-tumors

  Peripheral nerve tumors are growths that form in or near nerves. Most of them are benign, meaning they’re not cancerous. […] Peripheral nerve tumors are more common in people who have neurofibromatosis (types 1 and 2) and schwannomatosis. In these disorders, tumors develop on or near the nerves throughout the body. There are often multiple tumors. They can lead to a variety of symptoms depending on where they are in the body. These tumors are usually not cancerous. […] Peripheral nerve tumors aren’t common. It’s important to find a provider who is experienced in diagnosing and treating them. If needed, seek a second opinion.

• #2 Benign nerve tumours in the upper limb: a registry-based study of symptoms and surgical outcome | Scientific Reports

  https://www.nature.com/articles/s41598-023-38184-9

  Surgery for benign nerve tumours is performed for pathoanatomical diagnosis and symptomatic relief, but might cause residual problems. […] In total, 206 cases surgically treated for a benign peripheral nerve tumour 20102019 registered in the Swedish Quality Registry for Hand Surgery (HAKIR; response rates 2234%) were analysed. […] We conclude that surgery for benign peripheral nerve tumours provides good symptomatic relief with low risk for residual problems. […] The mean incidence of Schwannomas in the upper limb requiring surgical treatment has been approximated to 0.62 per 100 000 inhabitants and year. […] Due to the rarity of benign peripheral nerve tumours, the number of large descriptive and comparative studies are limited. […] The aim of this study was to assess patient-reported symptoms and disability before and after surgical intervention at a national level.

• #2 Collection of Rare Peripheral Nerve Tumors—Insights from the German Registry

  https://www.mdpi.com/2072-6694/16/14/2599

  In our experience, the prevalence of rare peripheral nerve tumors (PNTs) exceeds expectations, particularly following new histological diagnoses such as hybrid nerve sheath tumors. Recognizing their existence is vital for tailoring surgical approaches and treatment strategies and for considering adjuvant therapy when warranted. Our experience shows that conclusively distinguishing between benign PNTs and rare intrinsic and extrinsic tumors during preoperative diagnostics may be challenging. However, thorough clinical examinations and subtle imaging cues can at least hint at the presence of a rare entity.

• #2

  https://continentalhospitals.com/diseases/benign-peripheral-nerve-tumor/

  By understanding the potential causes of benign peripheral nerve tumors, healthcare professionals can better assess patients’ risk factors and provide appropriate care and treatment options. […] Regular medical check-ups and screenings become increasingly important as individuals reach this age range. […] It is worth noting that while these risk factors may increase the likelihood of developing benign peripheral nerve tumors, they do not guarantee their occurrence. […] By understanding these risk factors, individuals can take proactive steps towards early detection, proper diagnosis, and timely treatment if necessary. […] Accurate and timely diagnosis is crucial when it comes to benign peripheral nerve tumors. […] Regular check-ups with healthcare professionals are essential for early detection and intervention. […] In conclusion, prevention plays a vital role in managing benign peripheral nerve tumors. […] Regular communication with healthcare professionals can provide valuable guidance on managing individual risks and maintaining overall well-being.

• #2 PERIPHERAL NERVE TUMORS – Dr Prem Pillay

  https://singaporebrain.org/en/nerves/peripheral-nerve-tumors/

  MPNSTs are aggressive soft-tissue sarcomas accounting for about 10% or slightly more of all peripheral nerve sheath tumors. […] Imaging studies are central in delineating the location and extent of the tumor. […] In asymptomatic, slowly growing, small benign peripheral nerve tumors (usually a few mm in size) a watch-and-wait approach (also called monitoring) may be considered if they do not threaten function. […] Micro-surgical resection remains the mainstay of therapy for most peripheral nerve tumors, both benign and malignant. […] Adjuvant Radiotherapy: Often recommended for malignant peripheral nerve sheath tumors with larger lesion sizes or aggressive histological features. […] MPNSTs, unfortunately, do not respond robustly to conventional chemotherapy, though anthracycline-based regimens may be tried in inoperable or metastatic settings.

• #3 Benign nerve tumours in the upper limb: a registry-based study of symptoms and surgical outcome | Scientific Reports

  https://www.nature.com/articles/s41598-023-38184-9

  Surgery for benign nerve tumours is performed for pathoanatomical diagnosis and symptomatic relief, but might cause residual problems. […] In total, 206 cases surgically treated for a benign peripheral nerve tumour 20102019 registered in the Swedish Quality Registry for Hand Surgery (HAKIR; response rates 2234%) were analysed. […] We conclude that surgery for benign peripheral nerve tumours provides good symptomatic relief with low risk for residual problems. […] The mean incidence of Schwannomas in the upper limb requiring surgical treatment has been approximated to 0.62 per 100 000 inhabitants and year. […] Due to the rarity of benign peripheral nerve tumours, the number of large descriptive and comparative studies are limited. […] The aim of this study was to assess patient-reported symptoms and disability before and after surgical intervention at a national level.

• #3 Neurilemmoma (Schwannoma): Practice Essentials, Etiology, Epidemiology

  https://emedicine.medscape.com/article/1256405-overview

  Neurilemmoma is the most common neurogenic tumor, but precise prevalence figures have not been established. These tumors affect persons aged 20-50 years. No racial or sex predilection is recognized. Common locations for neurilemmomas are, in order of decreasing frequency, the head and neck, the flexor surfaces of the upper and lower extremities, and the trunk. […] Rare descriptions exist of malignant change in long-standing neurilemmomas. Malignant change is extremely rare in isolated lesions.

• #3 Benign peripheral nerve sheath tumors: an interdisciplinary diagnostic and therapeutic challenge

  https://pmc.ncbi.nlm.nih.gov/articles/PMC10439084/

  A benign peripheral nerve sheath tumor (bPNST) is a rare lesion associated with peripheral nerval structures. Symptoms may be heterogeneous, complicating diagnosis finding. […] Therefore, we analyzed patients treated for bPNST in our specialized institution with a primary focus on prior misdiagnosis and possible mistreatment. […] Eighty-five patients were included in the final analysis with schwannoma being the most prevalent histopathological diagnosis (schwannoma (75.3%, n=64), neurofibroma (12.9%, n=11), hybrid nerve sheath tumor (5.9%, n=5), and perineurioma (5.9%, n=5)). An incorrect primary diagnosis was detected in 44.7% (n=38), leading to suboptimal or insufficient treatment in these cases. […] For the first time, our data shows the quantity and impact of incorrect initial diagnosis in bPNST causing a delay in causative treatment or resulting in unnecessary or potentially harmful treatment.

• #3 Management of peripheral nerve sheath tumors: 17 years of experience at Toronto Western Hospital in: Journal of Neurosurgery Volume 128 Issue 4 (2018) Journals

  https://thejns.org/view/journals/j-neurosurg/128/4/article-p1226.xml

  A surgical series of 201 benign and malignant peripheral nerve sheath tumors (PNSTs) was assessed to characterize the anatomical and clinical presentation of tumors and identify predictors of neurological outcome, recurrence, and extent of resection. […] All surgically treated PNSTs from the Division of Neurosurgery at Toronto Western Hospital from 1993 to 2010 were reviewed retrospectively. Data were collected on patient demographics, clinical presentation, surgical technique, extent of resection, postoperative neurological outcomes, and recurrence. […] One hundred seventy-five patients with 201 tumors had adequate follow-up for analysis. There were 182 benign and 19 malignant PNSTs. Of the benign lesions, 133 were schwannomas, 21 of which were associated with a diagnosis of schwannomatosis. There were 49 neurofibromas, and 26 were associated with neurofibromatosis Type 1 (NF1). Patients presenting with schwannomas were significantly older than those with neurofibromas. Schwannomas were more readily resected than neurofibromas, with the extent of resection of the former influenced by tumor location. Patients with benign PNSTs typically presented with a painful mass and less frequently with motor deficits. The likelihood of worsened postoperative motor function was decreased in patients with fully resected tumors or preoperative deficits. Recurrence of schwannomas and neurofibromas were seen more frequently in patients diagnosed with NF3 and NF1, respectively. Subtotal resection was associated with the increased recurrence of all benign lesions. […] Outcomes following resection of benign PNSTs depend on tumor histopathology, tumor location, and genetic predisposition syndrome. Gross-total resection should be attempted for benign lesions where possible. The management of malignant PNSTs remains challenging, requiring a multimodal approach.

• #3 Benign peripheral nerve tumor | Beacon Health System

  https://www.beaconhealthsystem.org/library/diseases-and-conditions/benign-peripheral-nerve-tumor?content_id=CON-20341913

  Risk factors may be different based on the type of benign peripheral nerve tumor. […] For neurofibromas, having the genetic condition known as neurofibromatosis type 1 (NF1) is a risk factor. NF1 can cause someone to have several neurofibromas. But most people who have neurofibromas don’t have NF1. […] People with NF1 are also at increased risk for developing a malignant peripheral nerve sheath tumor. Its important for them to check in often with a health care professional to monitor that risk. […] For schwannomas, having the gene that causes schwannomatosis is a risk factor.

• #3 PERIPHERAL NERVE TUMORS – Dr Prem Pillay

  https://singaporebrain.org/en/nerves/peripheral-nerve-tumors/

  Peripheral nerve tumors are a heterogeneous group of neoplasms that arise from or affect nerves outside the brain and spinal cord. According to the 2021 WHO classification of the Central Nervous System (CNS), peripheral nerve sheath tumors (PNSTs) comprise a set of unique entities each with specific clinical, anatomical, histological, and molecular features. Broadly, PNSTs can be subdivided into benign and malignant forms, often reflecting differences in their behavior, prognosis, and recommended treatments. […] Patients with a peripheral nerve schwannoma may need to have screening of other nerves with MRI of the whole spine and Brain with gadolinium contrast to rule out multiple nerve tumors at other locations. […] Plexiform neurofibromas can transform into malignant peripheral nerve sheath tumors (MPNSTs) and therefore warrant close monitoring.

• #3 18F-FDG PET/CT Imaging Features of Benign Schwannomas | Journal of Nuclear Medicine

  https://jnm.snmjournals.org/content/60/supplement_1/2053

  Schwannomas are the most common benign peripheral nerve sheath tumor (BPNST). […] The primary aim of this study was to examine the 18F-FDG PET/CT imaging features of biopsy-proven schwannomas, noting multiple characteristics, including size, presence of calcifications, SUVmax, metabolic tumor volume (MTV), and total lesion glycolysis (TLG). […] Benign schwannomas may be large and demonstrate intense heterogeneous FDG activity, mimicking MPNSTs on F-FDG PET/CT. A significant proportion exhibit FDG activity above levels previously thought to be useful in differentiating BPNSTs from MPNSTs.

• #3 Hybrid peripheral nerve sheath tumors: report of five cases and detailed review of literature | BMC Cancer | Full Text

  https://bmccancer.biomedcentral.com/articles/10.1186/s12885-017-3350-1

  Hybrid peripheral nerve sheath tumors (PNSTs) have been recognized recently and were first included in the 4th edition of World Health Organization (WHO) Classification of Tumors of Soft tissue and Bone, published in 2013. […] Hybrid PNSTs are distinct tumors and are usually benign. However, rare case reports have described local recurrence and at least two recent case reports have described malignant transformation in these tumors. […] Those associated with NF1 carry a risk of malignant transformation to malignant peripheral nerve sheath tumors (MPNSTs). […] However, exact rates of recurrence and malignant transformation remain largely unknown owing to extreme rarity of these tumors. […] Rare case reports have described local recurrence. […] At least two recent case reports have described malignant transformation in hybrid PNSTs.

• #3

  https://continentalhospitals.com/diseases/benign-peripheral-nerve-tumor/

  Benign peripheral nerve tumors, also known as neurofibromas, are non-cancerous growths that develop on the peripheral nerves throughout the body. […] Neurofibromas can occur in individuals with a condition called neurofibromatosis, which is a genetic disorder characterized by the growth of multiple tumors along the nervous system. […] However, they can also develop sporadically in people without any underlying genetic predisposition. […] It is important to note that while these tumors are generally benign and do not pose a threat to life, there is a small risk of malignant transformation into a cancerous tumor called malignant peripheral nerve sheath tumor (MPNST). Therefore, it is crucial for individuals with neurofibromas to undergo regular medical evaluation and monitoring to ensure early detection of any potential changes or complications.

• #3 Peripheral nerve tumors // Middlesex Health

  https://middlesexhealth.org/learning-center/diseases-and-conditions/peripheral-nerve-tumors

  Peripheral nerve tumors are growths that form in or near nerves. Most of them are benign, meaning they’re not cancerous. […] Peripheral nerve tumors are more common in people who have neurofibromatosis (types 1 and 2) and schwannomatosis. In these disorders, tumors develop on or near the nerves throughout the body. There are often multiple tumors. They can lead to a variety of symptoms depending on where they are in the body. These tumors are usually not cancerous. […] Peripheral nerve tumors aren’t common. It’s important to find a provider who is experienced in diagnosing and treating them. If needed, seek a second opinion.

• #3 Benign nerve tumours in the upper limb: a registry-based study of symptoms and surgical outcome | Scientific Reports

  https://www.nature.com/articles/s41598-023-38184-9

  Surgical treatment of benign peripheral nerve tumours in the upper limb, excluding reoperations, generally improved symptoms and disability for affected patients with the largest benefit seen during the first 3three months after surgery and without further noticeable improvements at 12 months after surgery with high patient satisfaction. […] We conclude that surgical treatment of benign peripheral nerve tumours in the upper limb usually improve pain modalities and disability.

• #4 Collection of Rare Peripheral Nerve Tumors—Insights from the German Registry

  https://www.mdpi.com/2072-6694/16/14/2599

  The most common peripheral nerve tumors are of a benign nature and include schwannoma or neurofibroma. […] A definitive preoperative differentiation between benign peripheral nerve tumors and rare intrinsic and extrinsic tumors is often not possible. Clinical examination and subtle imaging clues can at least indicate the possibility of a rare entity. […] The multicentric peripheral nerve tumor registry provides multicentric data on rare tumorous lesions for the first time. This article aims to provide an overview of the clinical, imaging, and pathological features of uncommon lesions associated with peripheral nerves, emphasizing characteristics that set them apart from common peripheral nerve tumors like schwannoma and neurofibroma. […] In our surgical series, 19% of lesions were considered “rare” and associated with peripheral nerves. If we exclude the intrinsic rare PNTs, our cohort’s percentage of non-neural lesions is 5%. From this, it can be inferred that these rare tumors occur more frequently than previously thought. However, there are currently no data available on their incidences.

• #4 Nerve Sheath Tumors: Definition & Types

  https://my.clevelandclinic.org/health/diseases/22526-nerve-sheath-tumors

  Benign nerve sheath tumors are relatively rare. Schwannomas are most common in people between the ages of 50 and 60. Neurofibromas most often occur in people between the ages of 20 and 40. Plexiform neurofibromas usually develop before age 5. […] Malignant peripheral nerve sheath tumors are extremely rare, affecting about 1 out of every 10 million people each year. […] Most nerve sheath tumors are noncancerous. Theyre treatable with surgery and rarely come back. If your tumor cant be completely removed surgically, youll require ongoing monitoring. […] The risk of nerve sheath tumors becoming cancerous is very low. The greatest risk is for people with NF1 who develop plexiform neurofibroma. Malignant peripheral nerve sheath tumors have a poor prognosis, especially if the tumor is larger than 2 inches. Fewer than half of people with this condition live five years after diagnosis.

• #4 Benign peripheral nerve sheath tumors: an interdisciplinary diagnostic and therapeutic challenge

  https://pmc.ncbi.nlm.nih.gov/articles/PMC10439084/

  A benign peripheral nerve sheath tumor (bPNST) is a rare lesion associated with peripheral nerval structures. Symptoms may be heterogeneous, complicating diagnosis finding. […] Therefore, we analyzed patients treated for bPNST in our specialized institution with a primary focus on prior misdiagnosis and possible mistreatment. […] Eighty-five patients were included in the final analysis with schwannoma being the most prevalent histopathological diagnosis (schwannoma (75.3%, n=64), neurofibroma (12.9%, n=11), hybrid nerve sheath tumor (5.9%, n=5), and perineurioma (5.9%, n=5)). An incorrect primary diagnosis was detected in 44.7% (n=38), leading to suboptimal or insufficient treatment in these cases. […] For the first time, our data shows the quantity and impact of incorrect initial diagnosis in bPNST causing a delay in causative treatment or resulting in unnecessary or potentially harmful treatment.

• #4 Pathology Outlines – Schwannoma

  https://www.pathologyoutlines.com/topic/softtissueschwannoma.html

  Benign nerve sheath tumor arising from differentiated Schwann cells […] All ages can be affected […] More common in 30 – 60 years of age […] M = F […] 90% are sporadic, 3% with neurofibromatosis type 2, 2% with schwannomatosis, 5% with meningiomatosis with or without neurofibromatosis type 2 (StatPearls: Schwannoma [Accessed 10 November 2021])

• #4 PERIPHERAL NERVE TUMORS – Dr Prem Pillay

  https://singaporebrain.org/en/nerves/peripheral-nerve-tumors/

  Peripheral nerve tumors are a heterogeneous group of neoplasms that arise from or affect nerves outside the brain and spinal cord. According to the 2021 WHO classification of the Central Nervous System (CNS), peripheral nerve sheath tumors (PNSTs) comprise a set of unique entities each with specific clinical, anatomical, histological, and molecular features. Broadly, PNSTs can be subdivided into benign and malignant forms, often reflecting differences in their behavior, prognosis, and recommended treatments. […] Patients with a peripheral nerve schwannoma may need to have screening of other nerves with MRI of the whole spine and Brain with gadolinium contrast to rule out multiple nerve tumors at other locations. […] Plexiform neurofibromas can transform into malignant peripheral nerve sheath tumors (MPNSTs) and therefore warrant close monitoring.

• #4 Different Pathology of Peripheral Nerve Sheath Tumor in Neurofibromatosis Type 1: 3 Cases

  https://www.thenerve.net/DOIx.php?id=10.21129/nerve.2021.7.2.92

  Neurofibromatosis type 1 (NF1) is an autosomal-dominant hereditary disease with a prevalence of about 1 in 3000. […] Because NF1 patients are at higher risk of malignancy, which is the most common cause of death, surgical resection and pathologic confirmation are very important to the treatment of symptomatic or growing tumors in NF1 patients. […] The incidence of MPNST is approximately 0.001% in the general population. The recurrence rate is approximately 40% to 65%, and metastasis is found in 16% to 39% of patients. […] NF1 patients are at high risk of neoplastic disease; the overall risk of cancer in NF1 patients is 2.7 times higher and the risk of malignancy in 50-year-olds is approximately 20%. […] Therefore, appropriate surveillance is required for NF1 patients. […] Detection and treatment of atypical neurofibroma are important in NF1 patients. […] Our experience suggests that MRI findings are important and useful for the differentiation of three types PNSTs. […] Further study and specific management plans are needed for PNSTs in NF1.

• #5 Collection of Rare Peripheral Nerve Tumors—Insights from the German Registry

  https://www.mdpi.com/2072-6694/16/14/2599

  The most common peripheral nerve tumors are of a benign nature and include schwannoma or neurofibroma. […] A definitive preoperative differentiation between benign peripheral nerve tumors and rare intrinsic and extrinsic tumors is often not possible. Clinical examination and subtle imaging clues can at least indicate the possibility of a rare entity. […] The multicentric peripheral nerve tumor registry provides multicentric data on rare tumorous lesions for the first time. This article aims to provide an overview of the clinical, imaging, and pathological features of uncommon lesions associated with peripheral nerves, emphasizing characteristics that set them apart from common peripheral nerve tumors like schwannoma and neurofibroma. […] In our surgical series, 19% of lesions were considered “rare” and associated with peripheral nerves. If we exclude the intrinsic rare PNTs, our cohort’s percentage of non-neural lesions is 5%. From this, it can be inferred that these rare tumors occur more frequently than previously thought. However, there are currently no data available on their incidences.

• #5 Nerve Sheath Tumors: Definition & Types

  https://my.clevelandclinic.org/health/diseases/22526-nerve-sheath-tumors

  Benign nerve sheath tumors are relatively rare. Schwannomas are most common in people between the ages of 50 and 60. Neurofibromas most often occur in people between the ages of 20 and 40. Plexiform neurofibromas usually develop before age 5. […] Malignant peripheral nerve sheath tumors are extremely rare, affecting about 1 out of every 10 million people each year. […] Most nerve sheath tumors are noncancerous. Theyre treatable with surgery and rarely come back. If your tumor cant be completely removed surgically, youll require ongoing monitoring. […] The risk of nerve sheath tumors becoming cancerous is very low. The greatest risk is for people with NF1 who develop plexiform neurofibroma. Malignant peripheral nerve sheath tumors have a poor prognosis, especially if the tumor is larger than 2 inches. Fewer than half of people with this condition live five years after diagnosis.

• #5 Benign peripheral nerve sheath tumors: an interdisciplinary diagnostic and therapeutic challenge

  https://pmc.ncbi.nlm.nih.gov/articles/PMC10439084/

  A benign peripheral nerve sheath tumor (bPNST) is a rare lesion associated with peripheral nerval structures. Symptoms may be heterogeneous, complicating diagnosis finding. […] Therefore, we analyzed patients treated for bPNST in our specialized institution with a primary focus on prior misdiagnosis and possible mistreatment. […] Eighty-five patients were included in the final analysis with schwannoma being the most prevalent histopathological diagnosis (schwannoma (75.3%, n=64), neurofibroma (12.9%, n=11), hybrid nerve sheath tumor (5.9%, n=5), and perineurioma (5.9%, n=5)). An incorrect primary diagnosis was detected in 44.7% (n=38), leading to suboptimal or insufficient treatment in these cases. […] For the first time, our data shows the quantity and impact of incorrect initial diagnosis in bPNST causing a delay in causative treatment or resulting in unnecessary or potentially harmful treatment.

Zobacz więcej