Peritoneal strumosis, 10 years after laparoscopic surgery for mature cystic teratoma of the ovary: a case report

Peritoneal strumosis, a condition in which benign thyroid tissue spreads to the peritoneal cavity, is extremely rare. Here we report the first case of peritoneal strumosis, 10 years after laparoscopic surgery for mature cystic teratoma of the ovary. A 64-year-old woman was referred to our hospital due to suspicion of a recurrence of rectal carcinoma in September 2011. Under the diagnosis of recurrence and peritoneal dissemination of rectal carcinoma, she underwent laparoscopic surgery in October 2011. On laparoscopy, several small whitish nodules on the peritoneum and mesentery, diagnosed as benign thyroid tissue, were identified. After surgery, re-examination of her past history revealed that she had received a laparoscopic salpingo-oophorectomy for a right ovarian tumor at another hospital, 10 years prior. In the surgical record, spillage of fatty component was described during the laparoscopic surgery. Pathological diagnosis of mature cystic teratoma with a component of thyroid tissue had been made. Although rare, peritoneal strumosis must be kept in mind in the differential diagnosis of late complications after laparoscopic surgery for mature cystic teratoma of the ovary.