Obstructive rectal endometriosis treated by robot-assisted laparoscopic surgery: a case report.

Rectal endometriosis is a rare disease. A definitive diagnosis prior to surgery is often difficult. We encountered a patient with rectal sub-obstructive endometriosis that was treated by robot-assisted laparoscopic low anterior resection. A 43-year-old woman visited our hospital with suspected stenosis caused by upper rectal cancer. She had a 2-year history of constipation. We were unable to confirm the diagnosis through detailed examinations, including laparoscopy. Robot-assisted laparoscopic low anterior resection with D3 lymph node dissection was performed for both diagnosis and treatment. The postoperative specimen showed a submucosal tumor. The pathological examination confirmed rectal endometriosis. We herein describe a rare case of obstructive rectal endometriosis that we were unable to diagnose preoperatively. Robotic surgery was useful in this case, which involved extensive pelvic adhesion.