[Catamenial pneumothorax due to diaphragmatic endometriosis; report of a surgical case].

A 27-year-old female was complained repeated right pneumothorax. Each episode was obviously related to the onset of menstruation, suggesting catamenial pneumothorax. Thoracoscope revealed the presence of several fistulas in the central tendon of the diaphragm. Partial resection of the diaphragm including these lesions was performed under thoracoscopic procedure. Microscopic examination of the excised specimen showed endometriosis. The patient was followed without hormonal therapy, but recurrent pneumothorax occurred. For the catamenial pneumothorax, hormonal treatment is considered necessary even after surgical treatment.