This issue of Actas Dermo-Sifiliográficas includes a study of the clinical and pathologic features of leiomyosarcomas in a series of 12 patients followed for 15 years.1 Rodríguez-Lomba and colleagues found that 2 of the 4 dermal tumors recurred, 1 of the 2 subcutaneous tumors developed distant metastases, and 5 of the 6 metastases from noncutaneous tumors resulted in death. The authors remind readers of the importance of first ruling out the possibility of metastasis from an undiagnosed leiomyosarcoma when this type of tumor is found in the dermis. They also provide a highly useful algorithm to guide the dermatologist's diagnosis and treatment of these tumors based on histologic findings.

Leiomyosarcoma is a rare neoplasm that develops in muscle tissue. It accounts for 2% to 3% of all cutaneous sarcomas. Clinical signs and symptoms are nonspecific, and a biopsy must include fat-containing tissue for diagnosis.

These sarcomas, as explained by Rodríguez-Lomba et al1 and others,2,3 are traditionally classified in 3 groups with different prognoses: cutaneous, or dermal, forms; subcutaneous forms; and cutaneous metastasis from a noncutaneous leiomyosarcoma. The deeper the lesion, the worse the prognosis. Dermal leiomyosarcoma is of intermediate malignancy. Although it tends to recur locally (24%), the risk of metastasis is low (4%).2 Local spread (37%) and distant metastasis (43%) are more likely in subcutaneous leiomyosarcoma. Finally, metastatic leiomyosarcomas are signs of the progression of a primary tumor, and life expectancy is approximately 16 months after this form is diagnosed.3 The interesting findings Rodríguez-Lomba et al report in this issue are consistent with the earlier literature.