Spindle Cell Lipoma : Differential
The differential diagnosis of spindle cell lipoma includes:Dermatofibrosarcoma protuberans (location in dermis; prominent storiform pattern with infiltrative growth; younger patient; absence of collagen bundles)Nodular fasciitis (heterogenous appearance; myofibroblastic cells with tissue culture appearance; positive for SMA; lack of CD34 staining)Angiomyofibroblastoma (genital location; prominent vasculature consisting of thick-walled blood vessels; epithelioid cells)Solitary Fibrous Tumor (positive for STAT6 by immunohistochemistry; lacks 13q14 deletion)Cellular angiofibroma and mammary-type myofibroblastoma. Both entities share morphologic and cytogenetic features (deletion of 13q14) and the distinction may not be possible nor clinically relevant. This image shows a fat-free spindle cell lipoma with prominent myxoid matrix resulting in close resemblance to a myxoma. (differential diagnosis continues in the next slide).