2024 Volume 39 Issue 1 Pages 26-29
A 63－year－old woman visited our hospital for evaluation of a tumor that had been present on her right lower back for 20 years. Histopathological findings revealed spindle－shaped cells with a storiform pattern extending between the dermis and subcutaneous tissue and a large number of fat cells within the tumor. Immunohistochemical analysis revealed spindle－shaped cells with immunopositivity for CD34 and immunonegativity for S－100. The patient was diagnosed with dermatofibrosarcoma protuberans. Lipofibromatosis－like neural tumors represent the most common spindle－cell tumors that contain numerous fat cells. However, this diagnosis was excluded in this case based on negative results for pan－tropomyosin receptor kinase on immunohistochemical analysis.[Skin Cancer (Japan) 2024 ; 39 : 26－29]
