Benign leiomyoma metastasizing to the lung: a case report and a brief review of the literature

The authors have investigated a rare clinical condition consisting of a benign metastatic leiomyoma (BML) spreading in the lung, in a young woman. A 42-year-old woman affected by multiple pulmonary nodules histologically diagnosed as metastases from uterine sarcoma (one of them has been resected in the past and a pathologic diagnosis of uterine leyomiosarcoma was done) in concomitance with uterine bleeding, was referred to the Radiation Oncology Department of Taranto (Italy) Hospital, with the aim to perform an hemostatic radiotherapy after 4 cycles of induction chemotherapy. The patients underwent a myomectomy 9 years before. An accurate tissue samples review was performed both on myomectomy sample and on lung specimens, and as result, a diagnosis of BML was done, mainly on the basis of the mitotic activity. The patient was successfully treated with hysterectomy and oophorectomy followed by megestrol therapy, and a partial remission of the lung disease was obtained. Pulmonary metastatic leiomyomatosis should be considered in a premenopausal woman bearing a uterine myoma. The evaluation of the mitotic activity should be considered as the most reliable feature available to distinguish BML from uterine sarcoma.