Granular cell tumor (Abrikossoff tumor) of the clitoris

A 60-year-old woman presented to the Department of Dermatology of the ABC Medical Center in Mexico City with a 2-month history of a progressive growth in the region of the clitoris that had been increasing rapidly. Examination revealed a firm growth measuring 3 cm in diameter; the overlying surface was smooth and free of ulceration. Vaginal speculum examination showed no mucosal irregularities or displacement. Rectal examination was normal. Inguinal lymph nodes were clinically negative. A wide excisional biopsy was performed with ample skin margins.
The specimen consisted of a mass measuring 3.5 × 1.2 × 0.5 cm that was pale tan, homogeneous, and firm. Prepared sections showed a cellular tumor composed of compact irregular strands and nodules of polyhedral cells containing centrally located, round to oval vesicular nuclei with no significant atypia of mitosis. These cells had granular eosinophilic cytoplasm with distinct cell borders (Fig. 1). The cytoplasmic granules were diastase-resistant periodic acid-Schiff (PAS) positive. The tumor cells were positive for S–100 protein and for neuron-specific enolase (NSE), and were negative for actin, desmin, and cytokeratin. The tumor showed compression and obliteration of the cavernous sinuses (Fig. 2) outlined by the S–100 immunostain and actin. (Figs 3 and 4).