The term thoracic endometriosis has been used to describe the varying clinical and radiological manifestations associated with the growth of endometrial glands and stroma in the lungs or the pleural surface. Catamenial pneumothorax (CP) is defined as pneumothorax happening around the menstrual period and is the most common manifestation of thoracic endometriosis, accounting for about 80% of cases. In almost all cases, thoracic endometriosis is unilateral and right sided, although there are rare cases of left sided disease. Bilateral disease is extremely rare. The presentation of CP includes cough, chest pain, and shortness of breath. The chest pain may be similar to patients with spontaneous pneumothorax or present as shoulder, scapular or neck pain.
Some management strategies for thoracic endometriosis are as follows. For any women with a spontaneous recurring pneumothorax, a gynecologic history and evaluation of her menstrual cycle should be done. When thoracic endometriosis is suspected, Video-Assisted Thoracoscopic Surgery (VATS) is the preferred approach. The diaphragm needs to be explored thoroughly, including the visceral and parietal pleura, and if necessary, a port should be inserted at the subcostal margin to assess the posterior diaphragm. All accessible lesions and fenestrations should then be resected. Fulguration or ablation of lesions should not be used, as it is inadequate for treatment of endometriosis and will result in higher recurrence rates. Following the resection, plication is recommended to seal and strengthen the diaphragm. Simple suturing of the fenestrations does not provide tissue diagnosis and is usually followed by recurrence. Lesions close to the phrenic nerve or its main divisions are best treated by limited resection (if possible) and repair. A mechanical pleurodesis is also further recommended after all accessible lesions have been excised.
We also propose a joint surgery by the thoracic surgeon and the gynecologist specialized in endometriosis wherever possible. Not only will this allow for an assessment of the diaphragm from both the pleural and peritoneal side concurrently, this will also allow more thorough identification of endometriotic lesion and fenestrations by both specialists. Additionally, there is a significant association between the presence of pelvic endometriosis and thoracic endometriosis and a joint surgery will further allow the treatment of any pelvic endometriosis at the same time.
Medical treatment has long been considered the first choice in patients with thoracic endometriosis. The literature contains a variety of reports on the use of oral contraceptives, progestational drugs, danazol and gonadotropin-releasing hormone (GnRH) agonists. Experience in the last three decades has been greatest with danazol and GnRH agonists. However, the results of medical treatment for CP have been disappointing. At 6 and 12 months, surgical treatment of CP resulted in far lower recurrence rate than did hormonal therapy (5% and 25% compared with 50% and 60%). Therefore, before initiating pharmacologic disruption of ovarian steroid genesis in a young woman, all surgical treatment options should have been exhausted.
