Malignant peripheral nerve sheath tumor Microchapters Home Patient Information Overview Historical Perspective Classification Pathophysiology Causes Differentiating Malignant Peripheral Nerve Sheath Tumor from other Diseases Epidemiology and Demographics Risk Factors Screening Natural History, Complications and Prognosis Diagnosis Staging History and Symptoms Physical Examination Laboratory Findings X-Ray MRI Ultrasound Other Imaging Findings Other Diagnostic Studies Biopsy Treatment Medical Therapy Surgery Primary Prevention Secondary Prevention Cost-Effectiveness of Therapy Future or Investigational Therapies Case Studies Case #1 Malignant peripheral nerve sheath tumor overview On the Web Most recent articles Most cited articles Review articles CME Programs Powerpoint slides Images American Roentgen Ray Society Images of Malignant peripheral nerve sheath tumor overview All Images X-rays Echo & Ultrasound CT Images MRI Ongoing Trials at Clinical Trials.gov US National Guidelines Clearinghouse NICE Guidance FDA on Malignant peripheral nerve sheath tumor overview CDC on Malignant peripheral nerve sheath tumor overview Malignant peripheral nerve sheath tumor overview in the news Blogs on Malignant peripheral nerve sheath tumor overview Directions to Hospitals Treating Malignant peripheral nerve sheath tumor Risk calculators and risk factors for Malignant peripheral nerve sheath tumor overview Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Marjan Khan M.B.B.S.[2] ## Overview[edit | edit source] Malignant peripheral nerve sheath tumor (MPNST) is a form of cancer of the connective tissue surrounding nerves. On gross pathology, a large firm mass with necrosis and hemorrhage is the characteristic finding of malignant peripheral nerve sheath tumor. On microscopic histopathological analysis, spindle cells, nuclear atypia, mitoses, and herring bone pattern are characteristic findings of malignant peripheral nerve sheath tumor.[1] Neurofibromatosis type I (NF1) gene is involved in the pathogenesis of malignant peripheral nerve sheath tumor.[2] Malignant peripheral nerve sheath tumor must be differentiated from neurofibroma and schwannoma.[3] The incidence of malignant peripheral nerve sheath tumor is approximately 0.1 per 100,000 individuals worldwide.[4] The incidence of malignant peripheral nerve sheath tumor increases with age.[4] Malignant peripheral nerve sheath tumor affects men and women equally.[3] Common risk factors in the development of malignant peripheral nerve sheath tumor are pre-existing plexiform neurofibromas, pre-existing perineuriomas, radiation therapy, and neurofibromatosis type 1.[5][6][7] Symptoms of malignant peripheral nerve sheath tumor include peripheral edema, difficulty in moving the extremity, pain, and numbness.[8] MRI may be diagnostic of malignant peripheral nerve sheath tumor. Findings on MRI suggestive of malignant peripheral nerve sheath tumor include isointense on T1 weighted image and low signal on T2 weighted image.[3] The predominant therapy for malignant peripheral nerve sheath tumor is surgical resection. Adjunctive chemotherapy and radiation therapy may be required. Common complication of malignant peripheral nerve sheath tumor is metastasis. Prognosis is generally poor.[9] ## Classification[edit | edit source] There is no classification system established for malignant peripheral nerve sheath tumor. ## Pathophysiology[edit | edit source] On gross pathology, a large firm mass with necrosis and hemorrhage is the characteristic finding of malignant peripheral nerve sheath tumor. On microscopic histopathological analysis, spindle cells, nuclear atypia, mitoses, and herring bone pattern are characteristic findings of malignant peripheral nerve sheath tumor.[1] Neurofibromatosis type I (NF1) gene is involved in the pathogenesis of malignant peripheral nerve sheath tumor.[2] ## Causes[edit | edit source] Malignant peripheral nerve sheath tumor may be caused by a mutation on neurofibromatosis type I gene.[10][2] ## Differential Diagnosis[edit | edit source] Malignant peripheral nerve sheath tumor must be differentiated from neurofibroma and schwannoma.[3] ## Epidemiology and Demographics[edit | edit source] Malignant peripheral nerve sheath tumors comprise ∼2% of all sarcomas whichare a small fraction of a group of cancers that affect 5 people per million per year. The incidence of malignant peripheral nerve sheath tumor is approximately 0.1 per 100,000 individuals worldwide. The incidence of malignant peripheral nerve sheath tumor increases with age. Malignant peripheral nerve sheath tumor affects men and women equally. ## Risk Factors[edit | edit source] Common risk factors in the development of malignant peripheral nerve sheath tumor are pre-existing plexiform neurofibromas, pre-existing perineuriomas, radiation therapy, and neurofibromatosis type 1.[5][6][7] ## Screening[edit | edit source] According to the the U.S. Preventive Service Task Force (USPSTF), there is insufficient evidence to recommend routine screening for Malignant peripheral nerve sheath tumor.[11] ## Complication and prognosis[edit | edit source] In general Malignant peripheral nerve sheath tumor is known to have high metastatic potential and poor prognosis.[1] long-term outcomes vary widely across multiple series, with 5-year survival ranging between 15% and 50%. Large tumor size at presentation (typically >5 cm) has been the most consistently determined adverse prognostic factor. Other reported factors include tumor grade, truncal location, surgical margin status, local recurrence, and heterologous rhabdomyoblastic differentiation. The true prognostic impact of NF1 syndrome in MPNST remains somewhat in flux. Several large series report significantly worse outcomes for MPNST arising in the setting of NF1 compared with sporadic disease, with inferior responses to cytotoxic chemotherapy and 5-year survivals that are up to 50% worse. ## Diagnosis[edit | edit source] ### Staging[edit | edit source] There is no established system for the staging of malignant peripheral nerve sheath tumor. ### Symptoms[edit | edit source] Symptoms of malignant peripheral nerve sheath tumor include peripheral edema, difficulty in moving the extremity, pain, and numbness.[8] ### Physical Examination[edit | edit source] Common physical examination findings of malignant peripheral nerve sheath tumor include edema, paresthesia, and weakness. ### Laboratory Findings[edit | edit source] There are no laboratory findings associated with malignant peripheral nerve sheath tumor. ### X Ray[edit | edit source] There are no X-ray findings associated with malignant peripheral nerve sheath tumor. ### CT[edit | edit source] CT scan may be diagnostic of malignant peripheral nerve sheath tumor. Finding on CT scan suggestive of malignant peripheral nerve sheath tumor is a rapid growth mass with irrefular border.[3] ### MRI[edit | edit source] MRI may be diagnostic of malignant peripheral nerve sheath tumor. Findings on MRI suggestive of malignant peripheral nerve sheath tumor include isointense on T1 weighted image and low signal on T2 weighted image.[3] ### Ultrasound[edit | edit source] There are no ultrasound findings associated with malignant peripheral nerve sheath tumor. ### Other Imaging Findings[edit | edit source] Scintigraphy may be diagnostic of malignant peripheral nerve sheath tumor. Finding on Gallium67 scintigraphy suggestive of malignant peripheral nerve sheath tumor is higher uptake.[3] ### Other Diagnostic Studies[edit | edit source] There are no other diagnostic study findings associated with malignant peripheral nerve sheath tumor. ### Biopsy[edit | edit source] Biopsy is helpful in the diagnosis of schwannoma. ## Treatment[edit | edit source] ### Medical Therapy[edit | edit source] In the setting of localized disease, as is the case with all soft tissue sarcomas, complete surgical extirpation with clear margins is the treatment of choice.The predominant therapy for malignant peripheral nerve sheath tumor is surgical resection.In the setting of advanced or metastatic MPNST, outcomes are generally poor. Doxorubicin and ifosfamide are the most active agents in unselected soft tissue sarcomas, with a Response Evaluation Criteria in Solid Tumors (RECIST) response rate of approximately 25% for the combination. Adjunctive chemotherapy and radiation therapy may be required.Multiple retrospective datasets have shown the negative prognostic impact of involved margins and local recurrence. As in the case with most large (>5 cm) high-grade limb sarcomas, adjuvant radiation is advocated to reduce local recurrence. The risk-benefit profile of adjuvant radiation in patients with NF1 must be carefully discussed with all patients in view of the heightened risk of radiation-induced sarcomas. ### Surgery[edit | edit source] Surgery is the mainstay of treatment for malignant peripheral nerve sheath tumor. For patients suffering from neurofibrosarcomas in an extremity, if the tumor is vascularized and has many nerves going through it and/or around it, amputation of the extremity may be necessary. Some surgeons argue that amputation should be the procedure of choice when possible, due to the increased chance of a better quality of life. Otherwise, surgeons may opt for a limb-saving treatment, by removing less of the surrounding tissue or part of the bone, which is replaced by a metal rod or grafts. ### Primary Prevention[edit | edit source] There is no established method for prevention of malignant peripheral nerve sheath tumor. ### Secondary Prevention[edit | edit source] There are no secondary preventive measures available for malignant peripheral nerve sheath tumor. ## References[edit | edit source] 1. ↑ 1.0 1.1 Malignant peripheral nerve sheath tumor. Librepathology 2015. http://librepathology.org/wiki/index.php/Malignant_peripheral_nerve_sheath_tumour 2. ↑ 2.0 2.1 2.2 Ferrari, Andrea; Gianni Bisogno; Modesto Carli (2007). "Management Of Childhood Malignant Peripheral Nerve Sheath Tumor". Pediatric Drugs. 9 (4): 239–48. doi:10.2165/00148581-200709040-00005. PMID 17705563. `|access-date=` requires `|url=` (help) 3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Malignant peripheral nerve sheath tumor. Radiopaedia 2015. http://radiopaedia.org/articles/malignant-peripheral-nerve-sheath-tumour 4. ↑ 4.0 4.1 Bates JE, Peterson CR, Dhakal S, Giampoli EJ, Constine LS (2014). "Malignant peripheral nerve sheath tumors (MPNST): a SEER analysis of incidence across the age spectrum and therapeutic interventions in the pediatric population". Pediatr Blood Cancer. 61 (11): 1955–60. doi:10.1002/pbc.25149. PMID 25130403.CS1 maint: Multiple names: authors list (link) 5. ↑ 5.0 5.1 Perrin RG, Guha A (2004). "Malignant peripheral nerve sheath tumors". Neurosurg Clin N Am. 15 (2): 203–16. doi:10.1016/j.nec.2004.02.004. PMID 15177319. 6. ↑ 6.0 6.1 Baehring JM, Betensky RA, Batchelor TT (2003). "Malignant peripheral nerve sheath tumor: the clinical spectrum and outcome of treatment". Neurology. 61 (5): 696–8. PMID 12963767.CS1 maint: Multiple names: authors list (link) 7. ↑ 7.0 7.1 Kim DH, Murovic JA, Tiel RL, Moes G, Kline DG (2005). "A series of 397 peripheral neural sheath tumors: 30-year experience at Louisiana State University Health Sciences Center". J Neurosurg. 102 (2): 246–55. doi:10.3171/jns.2005.102.2.0246. PMID 15739552.CS1 maint: Multiple names: authors list (link) 8. ↑ 8.0 8.1 Valeyrie-Allanore L, Ismaïli N, Bastuji-Garin S, Zeller J, Wechsler J, Revuz J; et al. (2005). "Symptoms associated with malignancy of peripheral nerve sheath tumours: a retrospective study of 69 patients with neurofibromatosis 1". Br J Dermatol. 153 (1): 79–82. doi:10.1111/j.1365-2133.2005.06558.x. PMID 16029330.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link) 9. ↑ Neville H, Corpron C, Blakely ML, Andrassy R (2003). "Pediatric neurofibrosarcoma". J. Pediatr. Surg. 38 (3): 343–6, discussion 343–6. doi:10.1053/jpsu.2003.50105. PMID 12632346.CS1 maint: Multiple names: authors list (link) 10. ↑ Albright, A (2008). Principles and practice of pediatric neurosurgery. New York: Thieme. ISBN 1588903958. 11. ↑ Malignant peripheral nerve sheath tumor. U.S. Preventive Service Task Force (USPSTF) 2015. http://www.uspreventiveservicestaskforce.org/BrowseRec/Search?s=Malignant+peripheral+nerve+sheath+tumor Template:WikiDoc Sources