Cutaneous Myoepithelioma in the Foot

Abstract

Cutaneous myoepithelioma is a very rare, benign, subcutaneous and dermal tumor. It usually presents as a slow-growing and painless mass on the extremities. We report a case of cutaneous myoepithelioma that was located on the foot. A 68-yearold woman presented with a slowly growing pain-free mass on the right third toe measuring 0.8 × 0.7 × 0.4 cm3. We performed an elliptical excision, with histological and immunohistochemical analysis. The lesion showed dermis with cords of cytologically uniform ovoid cells with moderate amount of pale cytoplasm. No pleomorphism, mitotic activity, or necrosis was visualized. The tumor cells were positive for S-100 protein, epithelial membrane antigen and negative for smooth-muscle actin. From these findings, the tumor was diagnosed as a cutaneous myoepithelioma extending to the deep resection margin. To our knowledge, there are only 2 documented cases in the literature in English, and none have been reported in the foot and ankle literature. Levels of Evidence: Therapeutic, Level IV, Case study