title: Nodular fasciitis (pseudosarcomatous fasciitis) of the vulva.
abstract: Nodular fasciitis (pseudosarcomatous fasciitis) is a benign nonneoplastic connective tissue proliferation of unknown pathogenesis, which most commonly involves the upper limb subcutaneous fascia. Nodular fasciitis of the vulva is an entity rarely encountered by gynecologists or pathologists, but has considerable potential for misdiagnosis as sarcoma and for inappropriate treatment. The patient, a 32-year-old black female, presented with a 3-cm right labial mass, which was nodular, rubbery, and yellowish-white on section. Microscopically, there was an admixture of large mesenchymal cells, small blood vessels, and lymphocytes in a sparsely collagenous matrix. Other features included extravasated erythrocytes, intercellular clefts, and pseudocysts. Although mitoses were common (8 per 10 high power fields), there were no atypical mitoses and no bizarre tumor giant cells. The large mesenchymal cells were identified by electron microscopy as myofibroblasts, cells which abound in a variety of other reactive and non-neoplastic conditions. It is important not to misdiagnose nodular fasciitis as a vulvar sarcoma, because nodular fasciitis requires only simple excision and does not recur or metastasize.
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005208:Fasciitis / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D006801:Humans; D012509:Sarcoma / Q000175:diagnosis; D014844:Vulva / Q000473:pathology; D014845:Vulvar Diseases / Q000175:diagnosis / Q000473:pathology*; D014846:Vulvar Neoplasms / Q000175:diagnosis