[Catamenial Pneumothorax During Endometriosis Treatment].

Here, we report a case of catamenial pneumothorax that occurred during endometriosis treatment. A 46-year-old woman presented with a history of right pneumothorax. At 43 years of age, the patient was diagnosed with endometriosis and progesterone therapy was initiated. The patient developed rightsided chest pain and was diagnosed with right-sided pneumothorax. Video-assisted thoracoscopic surgery was performed, because of persistent air leakage. Intraoperative findings revealed a suspected pleural defect in the right upper lobe and multiple perforations around the central tendon of the right diaphragm. The pleural defect was resected, and the diaphragm surface was covered with a polyglycolic acid sheet. Pathologically, the diagnosis was associated with thoracic endometriotic pneumothorax, including immunostaining findings. Hormonal therapy was continued after discharge. The patient has remained free of recurrence for one year postoperatively.