Abstract

Introduction

Neurofibromatoses are a set of inherited disorders designated as neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2), and schwannomatosis which result in the development of benign nerve sheath tumors. These three clinical entities differ by specific clinical features and are result from mutations in distinct genes.^1,2 Segmental neurofibromatosis (SN) also known as a type V neurofibromatosis or mosaic-localized neurofibromatosis is a rare variant of the disease characterized by cutaneous lesions limited to a circumscribed body segment.

Despite the fact that NF is one of the most common inherited diseases (incidence 1/3000 births), SN is very rare with its prevalence is estimated between 0.0014 and 0.002%.³ It was first described by Crowe et al⁴ in 1956 who  termed it Sectorial neurofibromatosis. In 1977, Miller and Sparkes⁵ renamed this term as segmental neurofibromatosis (SNF). Riccardi⁶ included SNF in his classification of neurofibromatosis as type V.

The clinical features of SNF established by him include café-au-lait spots and/or neurofibromas in a single unilateral segment of the body, with no crossing of the median line, no family history, and no systemic involvement.

We hereby describe a patient who showed segmental expression and posed a diagnostic dilemma until biopsy report was obtained.

Case Report

A 55-year-old female presented with history of multiple small, mildly itchy, nodules over chin for last five years. The patient did not seek any investigations or treatment as the lesions were small and painless. Since then, she noted gradual increase in number of these lesions in the same area. She had no family history of neurofibromatosis.