Pituitary metastasis from medullary carcinoma of thyroid: case report and review of literature

Pituitary is a rare site for metastases from thyroid cancer. Most reported cases have been of papillary and follicular carcinoma. Metastases from medullary thyroid carcinoma have not been reported. We report a case of intrapituitary metastasis from medullary carcinoma thyroid in a 38-year-old male, who had been operated for pituitary adenoma 5 years earlier. At the time of presentation in Nov 2006, he had visual field defects and a painless thyroid nodule. Further evaluation revealed medullary carcinoma thyroid, cervical and mediastinal lymphadenopathy, elevated serum calcitonin levels, and lobulated pituitary tumor. After surgical excision of thyroid and lymph node clearance, he underwent craniotomy and subfrontal excision of pituitary tumor. All the tumors were of identical histology, i.e., medullary carcinoma thyroid. Pituitary tumor was positive for calcitonin.