Benign metastasizing leiomyoma of lung

Benign metastasizing leiomyoma (BML) is a rare condition in middle-aged women with uterine leiomyoma, characterized by extrauterine smooth muscle tumors mostly in both lungs, without evidence of other tumors. We report a case of 51-year-old woman with incidental finding of bilateral lung nodules on chest computed tomograms one year after hysterectomy for uterine leiomyomas. The patient underwent CT-guided transthoracic biopsy, with histo- pathological findings of tumor cells of smooth muscle differentiation. The final diagnosis of BML was confirmed by immunohistochemical staining which was positive for actin, desmin, estrogen and progesterone receptors.