title: Myxoid variant of dermatofibrosarcoma protuberans.
abstract: We describe two cases of dermatofibrosarcoma protuberans that were entirely myxoid when excised initially. The tumors had the following distinctive histologic features: 1) a monotonously haphazard arrangement of spindle-shaped and stellate tumor cells; 2) little variation in cellularity from field to field; 3) pale basophilic to clear stroma containing hyaluronic acid; 4) minimal cytologic pleomorphism and a low mitotic rate; 5) a dispersed, nonpatterned vasculature; 6) eccrine structures and fat cells trapped and surrounded by tumor tissue; and 7) areas where spindled cells had a parallel arrangement evocative of neurofibroma. A cutaneous tumor with the foregoing features should be carefully examined for subtle, radial arrangements of tumor cells and a tentacular or course, web-like infiltration of any attached fat. Use of the foregoing criteria will allow distinction between myxoid dermatofibrosarcoma protuberans and other myxoid tumors of the skin.
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000328:Adult; D002467:Cell Nucleus / Q000648:ultrastructure; D003593:Cytoplasm / Q000648:ultrastructure; D005260:Female; D005354:Fibrosarcoma / Q000098:blood supply / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008938:Mitosis; D012878:Skin Neoplasms / Q000098:blood supply / Q000473:pathology*