Cutaneous leiomyosarcoma is an extremely rare, malignant mesenchymal tumor of smooth muscle origin. Although generally considered a low-grade malignancy, there may be significant local invasion and subclinical extension. Rare cases of metastasis have been reported.

We sought to review the clinical characteristics and outcome of patients with cutaneous leiomyosarcoma treated with Mohs micrographic surgery (MMS) at our practice.

This study is a retrospective chart review of 11 consecutive patients with cutaneous leiomyosarcoma treated with MMS from 1995 through 2009. Patient demographic data, tumor size, location, previous treatment, number of Mohs stages to obtain clearance, surgical defect size, follow-up data, and presence or absence of recurrence were compiled and tabulated.

The average age of our 11 patients at time of diagnosis was 54.5 years. Three lesions were located on the head/neck and trunk, respectively, and 5 lesions were located on the extremities. Average preoperative clinical lesion size was 4.69 cm². Average number of MMS stages required for tumor clearance was 2.4. Average size of the surgical defect was 14.95 cm². One lesion was recurrent at the time of presentation. All remaining tumors were untreated. Mean follow-up after diagnosis was 4.47 years. No tumors recurred after MMS.

Our retrospective study had a small patient population, and follow-up data were less extensive for some patients.

These data represent the largest series in the literature of leiomyosarcoma treated with MMS, and establish that MMS is a useful modality for treating cutaneous leiomyosarcoma, a rare spindle cell malignancy that is not commonly encountered by physicians.