Abdominal wall endometriosis that developed at the port site after laparoscopic cholecystectomy

This case involved a 49-year-old woman who had undergone laparoscopic cholecystectomy in 1991 for cholecystolithiasis. Since April 2012, she had become aware of a painful subcutaneous mass at the umbilical port site. Surgery was recommended due to the possibility of malignancy. However, the patient had dysmenorrhea and endometriosis, and strongly wished to receive hormone therapy, which was performed in the gynecology department prior to any other procedures. Pain in the umbilical region subsequently improved, but recurred in September 2014 and she revisited the outpatient clinic. The mass had enlarged to around 30 mm, and the patient subsequently underwent mass excision under general anesthesia in November 2014. Since the mass was in contact with the anterior layer of the rectal sheath and the peritoneum, combined resection of a segment was performed and surgical repair using mesh was performed for the abdominal wall defect. Pathological findings indicated endometriosis. Although =90% of cases of abdominal wall endometriosis that occur at the site of a surgical scar are caused by previous gynecological surgery, we encountered an extremely rare case in which the patient developed this condition at the port site after laparoscopic cholecystectomy. We report herein our findings and observations.