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).
Their imaging appearances, demographics, treatment and prognosis vary greatly and these are therefore discussed separately.
Peripheral nerve sheath tumors may be classified as follows:
Imaging of a solitary peripheral nerve sheath tumor, in most cases, cannot reliably distinguish between the different histological subtypes, and a presumptive diagnosis must take into account the patient demographics, including pre-existing conditions (such as neurofibromatosis type 1 or neurofibromatosis type 2), the location and size of the tumor, and evidence of rapid growth. As such these are discussed separately in each of the aforementioned tumors. A number of features are, however, shared by localized neurogenic tumors of peripheral nerves.
As a group, localized peripheral nerve sheath tumors demonstrate the following features:
- 1. Lin J, Martel W. Cross-sectional imaging of peripheral nerve sheath tumors: characteristic signs on CT, MR imaging, and sonography. AJR Am J Roentgenol. 2001;176 (1): 75-82. doi:10.2214/ajr.176.1.1760075 - Pubmed citation
- 2. Wasa J, Nishida Y, Tsukushi S et-al. MRI features in the differentiation of malignant peripheral nerve sheath tumors and neurofibromas. AJR Am J Roentgenol. 2010;194 (6): 1568-74. doi:10.2214/AJR.09.2724 - Pubmed citation
- 3. Nagey L, McCabe SJ, Wolff TW. A case of neurofibroma of the palmar cutaneous branch of the median nerve. J Hand Surg Br. 1991;15 (4): 489-90. Pubmed citation
- 4. Chee DW, Peh WC, Shek TW. Pictorial essay: imaging of peripheral nerve sheath tumours. Can Assoc Radiol J. 2011;62 (3): 176-82. doi:10.1016/j.carj.2010.04.009 - Pubmed citation
- 5. Li CS, Huang GS, Wu HD et-al. Differentiation of soft tissue benign and malignant peripheral nerve sheath tumors with magnetic resonance imaging. Clin Imaging. 2008;32 (2): 121-7. doi:10.1016/j.clinimag.2007.05.006 - Pubmed citation