Management of intracranial metastases of differentiated carcinoma of thyroid.

Brain metastases in differentiated carcinoma of the thyroid is a rare occurrence. We treated five documented cases of carcinoma of thyroid with brain metastases out of 400 cases of thyroid cancer treated between 1972 to 1993. 4 were females out of which one was pregnant during the appearance of brain metastases. All cases were treated with thyroidectomy, and radioiodine as primary therapy. Brain metastases developed 6 months to 11 years following treatment of the primary and were treated with radiotherapy and suppressive levothyroxine. We observed the beneficial effect of suppressive thyroxine and the poor prognosis associated with pregnancy and withdrawal of thyroid replacement therapy. 3 of the 5 patients are alive 12-23 months after treatment for brain metastases, while 2 patients died at 4 months and 7 years post brain metastases due to pulmonary and hepatic failure, respectively.