Nodular Fasciitis of the Vulva

Abstract

Nodular fasciitis (NF) is a benign fibrous proliferative lesion, which histologically mimic a spindle cell sarcoma. It is easy to misdiagnose NF as a malignant lesion, especially in the unusual location. NF of the vulva is very rarely reported with only 13 cases on English literature. In Korea, no cases of vulvar NF have been reported. We report a case of vulvar NF occurring in a 56-yearold woman. The mass was relatively well-demarcated and measured 3.2 x 3.0 x 2.5 cm. Microscopically, the mass was composed of spindle cells with alternating hypercellular and hypocellular hyalinized fibrous areas. Mitotic figures were 1-2/10 High-Power Field. Immunohistochemical study of the mass for smooth muscle actin (SMA) yielded positive result. The CD34, desmin and ALK were negative. Ki-67 index was about 1%. Vulvar NF is noticeable to gynecologists and pathologists, because of its potential for misdiagnosis.