Pulmonary lymphangioleiomyomatosis followed by a localized retroperitoneal lymphangioleiomyoma.

Lymphangioleiomyomatosis is a rare disease that affects females of reproductive age. Microscopically, it is characterized by abnormal proliferation of immature smooth muscle-like cells that grow diffusely in the lung. Extrapulmonary manifestations in the mediastinum, peritoneum and pelvic lymph nodes are uncommon. We here describe a patient who initially presented with pulmonary lymphangioleiomyomatosis and subsequently developed a localized retroperitoneal mass. Pathologic examination showed that the mass was a lymphangioleiomyoma. The result of the immunohistochemical study was the same as that for the pulmonary lesion. It is therefore suggested that metastatic lymphangioleiomyoma should be included in the differential diagnosis in the patient with pulmonary lymphangioleiomyomatosis presenting with an extrapulmonary lesion.