Struma ovarii. Case report and revision of the literature

Struma ovarii is a rare form of ovarian neoplasm, entirely or predominantly composed of thyroid tissue. This tumour generally has a benign biological behavior, although some cases of malignant transformation have been reported (5-10%). The tumour usually presents as an asymptomatic mature mass that may measure as much as 10 cm in diameter. The presence of ascites is possible (15-20%), and in a few cases the association of ascites and hydrothorax has been recorded (Pseudo-Meigs Syndrome); a close relationship between ascites and high levels of Ca-125, that may wrongly induce to a diagnosis of ovarian carcinoma is present. Other possible clinical consequences are compressive symptoms on adjacent structures and symptoms of estrogenic-progestinal hyperproduction such as menometrorrhagia, dysmenorrhoea, infertility, and skin rash.Here we report the case of a young woman presenting, at her admission, a voluminous abdomino-pelvic mass (max. diam. 30 cm), histologically represented by a mature teratoma prevalently composed of thyroid tissue. Eur. J.Oncol., 16 (3), 000-000, 2011