A Case of Cutaneous Leiomyosarcoma of the Cheek

Leiomyosarcoma is a malignant neoplasm of smooth muscle origin that rarely occurs in external soft tissues of the head and neck region. We report a 61-year-old male with cutaneous leiomyosarcoma of the right cheek. The tumor, which had a rough surface, was 45×35mm in size, roundish in shape and well movable from the underlying tissues but not from the skin. The consistency was hard and elastic without tenderness. The tumor was completely excised with a margin of 25mm proximally. The defect of overlaying skin was reconstructed using a D-P flap. The tumor was composed of long spindle-shaped cells with blunting nuclei. Multinucleated giant cells and mitotic cells were also found. Immunohistochemical examinations showed that these cells were positive for anti α-smooth muscle actin antibody, but negative for S-100 protein, CD34, CD68 (Kp-1) and p53. A boxed-in appearance was observed by silver staining. This tumor was diagnosed as leiomyosarcoma by these findings. No local recurrence or distant metastasis were noted one year after the excision.