Umbilical endometriosis elucidates cause of recurrent pneumothorax

To the Editor: Endometriosis is characterized by ectopic endometrial tissue.1Bulun S.E. Endometriosis.N Engl J Med. 2010; 360: 268-279Crossref Scopus (1415) Google Scholar Cutaneous and thoracic variants are rare and challenging. We report a case of both cutaneous and thoracic endometriosis in the absence of surgery or prior endometriosis. Cutaneous findings secured the diagnosis of catamenial pneumothorax. A 44-year-old woman with no medical or surgical history developed dyspnea. Chest radiograph showed right-sided tension pneumothorax consistent with spontaneous pneumothorax that resolved after chest tube placement. Twelve months later, a bleeding umbilical papule developed. Pathologic study revealed endometrial tissue (Fig 1). She had no history of endometriosis, menstrual, or fertility issues. Another right-sided pneumothorax occurred 6 months later during menses. The cutaneous findings of endometriosis established a diagnosis of catamenial pneumothorax. Continuous oral contraceptives were initiated but a third right-sided pneumothorax occurred. Thoracoscopy identified diaphragmatic endometrial tissue (Fig 2). Leuprolide acetate was initiated. A fourth pneumothorax occurred 6 months later. The patient underwent bilateral oophorectomy with no recurrence at 44 months. Endometriosis, defined by endometrial tissue outside the uterus, affects 5% to 10% of reproductive aged females.1Bulun S.E. Endometriosis.N Engl J Med. 2010; 360: 268-279Crossref Scopus (1415) Google Scholar, 2Elm M.K. Twede J.V. Turiansky G.W. Primary cutaneous endometriosis of the umbilicus: a case report.Cutis. 2008; 81: 124-126PubMed Google Scholar Endometriosis, an estrogen-dependent inflammatory process, typically presents with dysmenorrhea, dyspareunia, and subfertility.1Bulun S.E. Endometriosis.N Engl J Med. 2010; 360: 268-279Crossref Scopus (1415) Google Scholar Ectopic endometrial deposits usually occur on pelvic surfaces and are rare outside the pelvis.1Bulun S.E. Endometriosis.N Engl J Med. 2010; 360: 268-279Crossref Scopus (1415) Google Scholar, 2Elm M.K. Twede J.V. Turiansky G.W. Primary cutaneous endometriosis of the umbilicus: a case report.Cutis. 2008; 81: 124-126PubMed Google Scholar Cutaneous endometriosis accounts for 1% of endometriosis and is most prevalent in surgical scars from cesarean section, hysterectomy, and laparoscopic procedures due to physical transplantation of endometrial cells during surgery.2Elm M.K. Twede J.V. Turiansky G.W. Primary cutaneous endometriosis of the umbilicus: a case report.Cutis. 2008; 81: 124-126PubMed Google Scholar, 3Eckford S. Westgate J. A cure for pneumothorax during menstruation.Lancet. 1996; 347: 734PubMed Scopus (11) Google Scholar Umbilical endometriosis is rare but can occur in women without a history of endometriosis or surgery, perhaps from lymphatics transporting endometrial tissue.2Elm M.K. Twede J.V. Turiansky G.W. Primary cutaneous endometriosis of the umbilicus: a case report.Cutis. 2008; 81: 124-126PubMed Google Scholar Catamenial pneumothorax occurs within 72 hours of menses due to ectopic endometrial tissue eroding into the pleura. Rare, it affects women in their third and fourth decades.3Eckford S. Westgate J. A cure for pneumothorax during menstruation.Lancet. 1996; 347: 734PubMed Scopus (11) Google Scholar Thoracic endometriosis typically presents with pneumothorax, but hemothorax, hemoptysis, and lung nodules are also reported.4Roberts L.M. Redan J. Reich H. Extraperitoneal endometriosis with catamenial pneumothoraces: a review of the literature.JSLS. 2003; 7: 371-375PubMed Google Scholar In 95% of cases, pneumothorax is right-sided. The mechanism of catamenial pneumothorax is unclear. The metastatic theory involves retrograde implantation of endometrial tissue from the pelvis to the lungs via lymphatics or congenital fenestrations in the diaphragm.4Roberts L.M. Redan J. Reich H. Extraperitoneal endometriosis with catamenial pneumothoraces: a review of the literature.JSLS. 2003; 7: 371-375PubMed Google Scholar, 5Papafragaki D. Concannon L. Catamenial pneumothorax: a case report and review of the literature.J Womens Health. 2008; 17: 367-372Crossref PubMed Scopus (15) Google Scholar Once implanted, endometrial tissue bleeds with menses, causing a pneumothorax. The right hemidiaphragm contracting against the solid, fixed liver on the right side may allow for ectopic endometrial migration and implantation. The anatomic model postulates the dissolution of the cervical mucus plug during menses, allowing air to travel from the vagina to the uterus, through the fallopian tubes, and into the peritoneum. If congenital fenestrations of the diaphragm are present, intraperitoneal air ascends into the pleural cavity, causing pneumothorax.4Roberts L.M. Redan J. Reich H. Extraperitoneal endometriosis with catamenial pneumothoraces: a review of the literature.JSLS. 2003; 7: 371-375PubMed Google Scholar, 5Papafragaki D. Concannon L. Catamenial pneumothorax: a case report and review of the literature.J Womens Health. 2008; 17: 367-372Crossref PubMed Scopus (15) Google Scholar Estrogen drives endometriosis. Treatment focuses on estrogen inhibition via hormonal (oral contraceptives, GnRH analogues, danazol, and aromatase inhibitors) or surgical treatments.1Bulun S.E. Endometriosis.N Engl J Med. 2010; 360: 268-279Crossref Scopus (1415) Google Scholar, 4Roberts L.M. Redan J. Reich H. Extraperitoneal endometriosis with catamenial pneumothoraces: a review of the literature.JSLS. 2003; 7: 371-375PubMed Google Scholar, 5Papafragaki D. Concannon L. Catamenial pneumothorax: a case report and review of the literature.J Womens Health. 2008; 17: 367-372Crossref PubMed Scopus (15) Google Scholar Hormonal treatment alone is often insufficient to completely suppress estrogen. Due to estrogen production via peripheral conversion of androgen, surgical treatment alone is not always definitive.5Papafragaki D. Concannon L. Catamenial pneumothorax: a case report and review of the literature.J Womens Health. 2008; 17: 367-372Crossref PubMed Scopus (15) Google Scholar Recurrences are common and require combination treatment. The diagnosis of catamenial pneumothorax was secured after correlating the rare diagnosis of umbilical endometriosis with pneumothorax associated with menses, emphasizing the importance of skin findings in the diagnosis of systemic disease.