Peritoneal strumosis.

A rare case of peritoneal strumosis is described. A 49-year-old woman was operated on because of a uterine leiomyoma. Laparotomy disclosed a left sided ovarian mass and multiple implants in the omentum. Microscopic examination revealed a benign ovarian struma with omental spread. There were no signs of a thyroid neoplasm. 32 months later and after three courses of chemotherapy, the patient was free of the disease. Although the nature of this lesion is equivocal, one cannot exclude maturation of a highly differentiated follicular cancer which could have arisen in the ovarian struma.