[Multiple leiomyomatous pulmonary nodules in women. Apropos of 2 cases of metastasizing benign leiomyoma].

Two cases of multiple pulmonary leiomyomas in women aged 51 and 45 years respectively are reported. The lesions were discovered 21 and 11 years respectively after hysterectomy for uterine fibromyoma without abnormal histological features. The pulmonary nodules were bilateral and either stable or growing slowly. They were revealed by non-specific symptoms. At surgical biopsy the histological picture was one of benign leiomyoma without mitosis. In one of the 2 patients a pulmonary nodule was explored for oestrogen and progesterone receptors with positive results. The various theories on the origin of these multiple leiomyomas are reviewed. Initially regarded as malformative tumours, they were later interpreted as metastases of uterine leiomyomas with a potential for dissemination. The finding of hormone receptors demonstrates a relationship between these pulmonary lesions, uterine leiomyomas and other multifocal leiomyomatous diseases, including lymphangioleiomyomatosis. The slow but benign course of these tumours differentiates them from metastases of low-malignancy leiomyosarcomas.