Benign metastasizing leiomyoma presenting as cavitating lung nodules.

Benign metastasizing leiomyoma (BML) was initially used to describe single or multiple pulmonary nodules composed of proliferating smooth muscle cells (lacking cellular atypia) in premenopausal females 3 months to 20 y after hysterectomy for uterine leiomyoma. The lung is the most commonly involved site, thus including many malignant and benign entities in the differential diagnosis. The present case refers to a 47-y-old premenopausal woman with a history of subtotal hysterectomy for a uterine leiomyoma presenting with bilateral cavitating pulmonary nodules. A number of nodules were resected by video-assisted thoracoscopic surgery. The histological findings in correlation with the immunohistochemical results were consistent with the diagnosis of BML. A bilateral salpingo-oophorectomy was performed, combined with complete removal of the remaining cervix. One year later, the subject remains asymptomatic, and the pulmonary nodules are stable with regard to number, size, location, and morphology.