title: Radiological findings of malignant peripheral nerve sheath tumor: reports of six cases and review of literature.
abstract: BACKGROUND
  Malignant peripheral nerve sheath tumor (MPNST) is a kind of rare neurogenic tumor. If associated with neurofibromatosis type 1, MPNST usually has a higher mortality. The aim of the article is to assess the imaging characteristics of MPNST and compare them with those of benign peripheral nerve sheath tumor (BPNST) to characterize this tumor.
  
  
  METHODS
  Clinical and imaging data of six cases with MPNST and 28 cases with BPNST in our institution since 2011 were retrospectively reviewed. Thirty-three patients have available MR imaging data, and two patients of MPNST also accepted CT scan. One patient accepted CT scan only. Location, size, shape, signal or density, boundary, bone destruction, relation to adjacent nerve, contrast-enhanced features as well as some other signs were assessed and compared with statistical software. Student's t test was used for comparison of continuous variables. Fisher's exact test was used for analysis of nominal variable. A P value ≤0.05 was considered to be statistically significant.
  
  
  RESULTS
  Differences existed between two groups in tumor size ((7.2 ± 3.3)cm in MPNST vs. (3.8 ± 1.4)cm in BPNST), unclear margin (4/6 in MPNST vs. 1/28 in BPNST), eccentricity to the nerve (1/6 in MPNST vs. 21/28 in BPNST), intratumoral lobulation (4/6 in MPNST vs. 2/28 in BPNST), peritumoral edema (3/6 in MPNST vs. 0 in BPNST), and peripheral enhancement (4/6 in MPNST (three of five MR, one CT) vs. 4/28 in BPNST). Bone destruction was observed in one MPNST.
  
  
  CONCLUSIONS
  MR imaging is a valuable, non-invasive modality for the diagnosis of MPNST. Peripheral enhancement with non-cystic appearance or remarkable heterogeneous enhancement may be useful for differential diagnosis. Other imaging features such as large size (over 5 cm in diameter), ill-defined margin, intratumoral lobulation, peritumoral edema, and adjacent bone destruction are also supportive of MPNST.
authors.affiliation: Department of Medical Imaging, Subei People's Hospital of Jiangsu Province, 98# Western Nantong Road, Yangzhou, 225001, China.
authors.forename: Yong-hui
authors.initials: YH
authors.lastname: Yu
authors.affiliation: Department of Medical Imaging, Subei People's Hospital of Jiangsu Province, 98# Western Nantong Road, Yangzhou, 225001, China. wujingtaodoctor001@126.com.
authors.forename: Jing-tao
authors.initials: JT
authors.lastname: Wu
authors.affiliation: Department of Medical Imaging, Subei People's Hospital of Jiangsu Province, 98# Western Nantong Road, Yangzhou, 225001, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.affiliation: Department of Medical Imaging, Subei People's Hospital of Jiangsu Province, 98# Western Nantong Road, Yangzhou, 225001, China.
authors.forename: Ming-xiang
authors.initials: MX
authors.lastname: Chen
mesh_terms: D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018317:Nerve Sheath Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D010524:Peripheral Nervous System Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: MR imaging; Nervous-peripheral; Tomography; X-ray computer