Extraneural Soft Tissue Perineurioma; A Rare Case Report

Abstract

Perineuriomasare rare benign peripheral nerve sheath tumors [PNSTs] exclusively composed of well-differentiated neoplastic perineurial cells. . Traditionally Perineurioma were thought to be neural only but the extraneural forms are also well known, infact more commonly documented. These are further subclassified into classical, sclerosing, and reticular/retiform subtypes. Here we describe a case of 30 year  female  with  right  thigh  mass  since  four  years  and  was  diagnosed  as  a  case  of  Soft  tissue Perineurioma  with  classical  morphology  of  bland    spindle  to  oval  cells  with  fibrillary  cytoplasm arranged  in  vague  storiform  pattern  and  also  forming    whorls  with  a  prominent    perivascular  arrangement (onion bulb formation) and  characteristic  IHC picture that was  EMA positive and S 100 negative