A case of pseudoangiomatous spindle cell lipoma

Abstract

Spindle cell lipoma, an entity first described in 1975, accounts for about 1.5% of adipocytic neoplasms and is outnumbered by conventional benign lipomas by approximately 60 to 1. We report an unusual pseudoangiomatous variant of spindle cell lipoma on the right thigh of a 78-year-old man. The lesion had the features of typical spindle cell lipoma which was composed of mature fat cells and uniform spindle cells in a mucoid matrix with collagen bundles. In addition, the lesion exhibited irregular, branching spaces with villiform connective tissue projections, giving a striking angiomatoid appearance. Inmwnohistochemically, the spindle cells were positive for CD34, and lining cells of pseudoangiomatous spaces were negative for CD31, factor VIII-Ag.