A Case of Thoracic Endometriotic Pneumothorax which Appeared Not to be Associated with Menstrual Periods

Abstract

A 47-year-old woman with previous history of right pneumothorax had recurrence of right pneumothorax half a year after the initial episode. Responsible lesion such as bulla was unclarified on a chest CT scan. As her disease was recurrent pneumothorax, we performed thoracoscopic surgery, but responsible lesions were obscure histologically as well as macroscopically. During postoperative two years, she experienced two episodes of recurrent right pneumothorax, however, her menstruation onset had not occurred before or after each episode. The fifth episode of right pneumothorax occurred 4 years after the first episode, when her menstruation started 6 days after the onset of fifth episode. We thus performed reoperation and found a macroscopic small pores on the diaphragm. The diaphragm pores were resected. Histologically endometriotic tissue was also proved, and the case was diagnosed as thoracic endometriotic pneumothorax. The disease does not always occur in conjunction with menstrual cycle. In order to confirm pores on the diaphragm caused by endometriosis or to make the histologic diagnosis, thoracoscopic surgery is needed. However, such pores are repaired and closed due to periodic change of endometrial tissue so that histologic diagnosis cannot be gained in many cases. To gain the histologic diagnosis, consideration of timing of surgery is important and just before menstruation onset or early time after the onset would be desirable.