Cutaneous leiomyosarcoma: a 20-year retrospective study and review of the literature

Background: Cutaneous leiomyosarcoma is a rare malignant neoplasm with muscular origin, representing 2%-3% of all cutaneous soft tissue sarcomas. Objectives: The aim of this study was to characterize clinicopathological features of patients diagnosed with cutaneous leiomyosarcoma in our center over the last 20-years. Methods: A retrospective study of patients with a histopathological diagnosis of leiomyosarcoma between 1999 and 2018 was conducted. Results: Eleven patients were diagnosed with cutaneous leiomyosarcoma during this period. Most cases occurred in men (n = 7). Age at presentation ranged from 47 to 92 years (mean 64.9 years). Head and neck were the most frequently involved locations (n = 5). Ten leiomyosarcoma were dermal, with one cutaneous metastasis. Immunohistochemical staining was available for 7 patients, demonstrating positivity for smooth muscle actin in all of them. All neoplasms were treated surgically. Mean survival was 32.2-months. Study limitations: This was a retrospective study based on medical and pathological records. Conclusions: Histopathology is essential for the diagnosis of leiomyosarcoma, usually revealing a dermal or subcutaneous lesion composed of intertwined fascicles of smooth muscle fibers. Immunohistochemistry is then used to adequately differentiate leiomyosarcoma from other spindle cell tumors. When dealing with cutaneous leiomyosarcoma, it is advisable to carefully-evaluate the depth of subcutaneous extension, since even minimal subcutaneous involvement may be associated with a poorer prognosis. (c) 2021 Sociedade Brasileira de Dermatologia. Published by Elsevier Espana, S.L.U.