[Dermoid cyst with thyroid follicle perforated into bladder and ileum: a case report].

A 64-year-old woman was admitted to our hospital on August 19, 1996 with the chief complaint of microscopichematuria. A solid mass was found in her lower abdomen. An abdominal CT scan suggested a large intrapelvic cystic mass and the existence of a fistulous connection between the mass and the small intestine. The existence of a fistula was confirmed by a preoperative barium enema and a cystscopic study. On September 25, 1996, a suprapubic partial cystectomy and total hysterectomy were performed since an intrapelvic abscess was suspected. The cystic mass was observed to adhere to the hollow viscus (uterus, rectum, appendix, ileum and bladder). As a result a part of the ileum and bladder were also removed with the mass. The contents of the cyst included a foul smelling gas and white-green pus. Using a probe, we found two fistulous openings to the ileum and bladder. The histopathological findings indicated a dermoid cyst of the left ovary with thyroid follicles, which are known as "Struma ovarii".