[Lymphangiomyomatosis with a large retroperitoneal tumor]

A case of lymphangiomyomatosis (LAM) in a 35-year-old woman is reported. Because she was already severely dyspneic when she was admitted to our hospital, neither TBLB nor open lung biopsy was performed, and no accurate diagnosis was made. She died of respiratory failure three years after the development of exertional dyspnea, and autopsy revealed LAM. Pneumothorax, a well-known and frequent complication of LAM, did not occur until one month prior to her death. Although pneumothorax frequently complicates LAM, there are a few reports of cases in which pneumothorax did not occur during the course of the disease. We emphasize that LAM should be considered in the differential diagnosis of diffuse interstitial lung disease, even when the patient has no pneumothorax. The retroperitoneal tumor (15 x 10 x 10 cm), which was evident clinically, was later shown to be intra-abdominal involvement of LAM. Although only a few cases of LAM with a large retroperitoneal tumor have been reported, minor intra-abdominal involvement is relatively common. This case also suggested that the finding of a retroperitoneal tumor may be a diagnostic clue in LAM.