A case of benign metastasizing leiomyoma treated by surgical castration followed by an aromatase inhibitor, anastrozole

Benign metastasizing leiomyoma (BML) is a rare disease most often located in the lungs of women with a history of surgery for benign leiomyoma of the uterus. Optimum therapy for BML, has not been established. We report here an additional case of BML in the lung that was successfully treated with surgical castration followed by hormonal therapy with anastrozole, an aromatase inhibitor. A 46-year-old primigravid Japanese woman was admitted to our hospital for investigation of multiple pulmonary nodules found on a routine chest X-ray. At the age of 36, she had undergone myomectomy for uterine myomas. Upon gynecological examination, her uterus, was enlarged to the size of a child's head. Abdominal total hysterectomy, bilateral salpingo-oophorectomy, and thracoscopic biopsy of pulmonary nodules were performed. Histologically, the lung nodules were diagnosed as BML. Subsequently oral anastrozole was started. The patient is alive and the size of the pulmonary nodules was stable, 15 months following the surgery. In addition to castration by bilateral oophorectomy or gonadotropin-releasing hormone agonist, the use of aromatase inhibitor is one of the treatment options for the further suppression of peripheral estrogen production in these patients.