Unusual Presentations of Plexiform Neurofibroma: A Series of Three Cases

Abstract

Neurofibroma is a benign peripheral nerve sheath tumour, and Plexiform Neurofibroma (PN) is pathognomonic of Neurofibromatosis Type 1 (NF1). It occurs equally in males and females and presents at birth or a very early age. The incidence is 1 in 2500 births per year, with an estimated genital association of 1.8%, where clitoral involvement is very rare in the Indian population. In the present case series, three patients were diagnosed with PN through surgical histopathology and Immunohistochemical (IHC) stains like S-100 and Cluster Differentiation 34 (CD34) at a tertiary care hospital. All three patients were children who had painless, gradually increasing swellings that underwent surgical treatment. Among them, a five-year-old girl presented with painless clitoromegaly, multiple café- au-lait spots, and underwent plastic surgery. She was later clinically diagnosed with NF1 after histopathological and IHC correlation. A two-year-old boy with a firm swelling over his left leg showed hyperintensity and multilobulation on magnetic resonance imaging. A 10-year-old boy with a similar swelling in his right upper arm showed multiple hypoechoic masses on ultrasonography. Both of them were later diagnosed with PN using the same methodology. Although it is benign, there is a risk of malignant transformation in diffuse PNs, and they should be managed by wide excision with a safety margin to prevent recurrence.