Hyperthyroidism with Struma ovarii.

Struma ovarii or monodermal teratoma, is a specialized ovarian neoplasm composed entirely of mature thyroid tissue. It is a relatively rare tumor which comprises 1% of all ovarian tumors and 2.7% of all dermoid tumors. Its colour and consistency is like that of a thyroid tissue. The tissue may show any of the pathologic changes seen in a normally placed gland, including diffuse or nodular hyperplasia, thyroiditis, papillary carcinoma, follicular carcinoma and malignant lymphoma. We reported a case of hyperthyroidism with struma ovarii. A 70 year old female was operated for ovarian mass. The sign and symptoms subside after operation.