Scar endometriosis in the rectus abdominis muscle

Endometriosis is defined as the presence of ectopic functional endometrial tissue outside the uterine cavity. The most common locations are within the pelvis. Unusual sites of endometriosis outside the pelvis have been reported, including the bladder, intestine, appendix, surgical scars, hernia sac, lung, kidney, and extremities. The diagnosis of scar endometriosis is usually not difficult and is based on history and physical examination. We report here two cases who developed endometriosis on the abdominal wall in the rectus abdominis muscle and were treated with local excisions.