The positivity for CD99 and BCL2 in this case suggests that the tumor is quite different from classic myofibroblastic proliferations, such as nodular fasciitis, fibromatosis, and dermatofibroma, as well as from benign and malignant smooth muscle proliferations, which are all uniformly negative for these antigens. The gene discussed is BCL2; the disease is cutaneous fibrous histiocytoma.