Subcutaneous Solitary Fibrous Tumor: A Case Report

Abstract

We describe a 28-year-old woman with a solitary fibrous tumor at supra-pubic subcutis. The sites affected by this mesenchymal tumor include pleuropulmonary, meningeal, gastrointestinal, bones, liver, kidney, thyroid, soft tissues, and skin. More often, they occur in the head, extremities, back and shoulder. Cutaneous lesions are frequently described in the head of female individuals. Predominant histological findings include fascicles of spindle cells, staghorn-like blood vessels, and a variable amount of mitotic figures up to 10 per 10 high-power fields. Classical immunohistochemistry markers are CD34, STAT-6, CD99, and Bcl-2; while the epithelial membrane antigen and the S100-protein are usually negative. This pattern associated with the lack of adnexal entrapment constitutes the major resource in differential diagnosis with superficial tumors CD34 positive; for instance, the spindle cell lipoma, and the dermatofibrosarcoma protuberans. Follow-up care after tumor excision plays a role in the early detection of a recurrence.