A case of uterine leiomyosarcoma metastasized to the skin: Local recurrence and rapid growth after excision

Abstract

Leiomyosarcoma is a rare malignant neoplasm of smooth muscle cells usually found in the uterus, retroperitoneum, gastrointestinal tract, or deep soft tissue. Metastasis of leiomyosarcoma tends to occur through hematogenous routes. Cutaneous metastasis is therefore a rare occurrence. A 57-year-old female presented with several weeks history of a solitary erythematous 0.8×0.8 cm sized firm nodule on the scalp. She had a past history of transabdominal hysterectomy due to primary uterine leiomyosarcoma and pulmonary lobectomy due to metastatic lung nodules. Histopathologic examination of her scalp nodule revealed a poorly circumscribed tumor mass composed of malignant spindle cells with abundant eosinophilic cytoplasm, elongated and blunt ended nuclei, and frequent mitotic activity. Immunohistochemical staining with caldesmon was positive. After 3 weeks, a 1.5×3.5 cm sized tumor had developed at the previous excision site. From these findings, we diagnosed this case of uterine leiomyosarcoma metastasized to the skin as a local recurrence with rapid growth after excision.