Abstract
Leiomyosarcomas of the skin are divided into two subtypes based on their origin and location: superficial dermal leiomyosarcoma believed to originate from the arrector pili muscles and sweat glands, and subcutaneous leiomyosarcoma arising from vascular smooth muscle of subcutaneous adipose tissue. Preoperative misdiagnosis is common because it is a rare malignant tumor, and the diagnosis is based on histopathological and immunohistochemical studies. Although superficial cutaneous leiomyosarcoma is usually treated with surgical excision, high rates of local recurrence (30–50%) have been reported. Subcutaneous leiomyosarcomas tend to be more aggressive, and since they are usually diagnosed at a more advanced stage, they are usually larger than superficial dermal based neoplasms. Recurrence rates are higher at 50–70%, and up to 60% of distant metastases have been reported. Guidelines for surgical management and role of radiation and chemotherapy as adjuvant treatments are not clearly defined. The clinicopathological features of this rare cutaneous soft tissue neoplasm are described, along with a review of the literature. Differential diagnoses, possible histogenesis, clinical behavior, management, and prognostic factors are also discussed.