What's in the Image? Pituitary Metastasis from Papillary Carcinoma of the Thyroid: A Case Report and a Comprehensive Review of the Literature.

A 67-year-old female patient presented with visual field impairment and hyperprolactinemia. Imaging revealed a sellar and suprasellar mass and during the evaluation of the sellar lesion, papillary thyroid carcinoma (PTC) was diagnosed by fine-needle aspiration biopsy in a long-standing euthyroid multinodular goiter. The patient did not have a previous history of PTC. Total thyroidectomy confirmed the diagnosis of PTC. Due to progressive visual loss, she underwent transcranial surgery for decompression of the optic chiasm. Pituitary metastasis from PTC was confirmed, histologically and immunohistochemically. In literature, overall 13 cases, including ours, with PTC metastasis to the sellar region have been reported. Most were women, with a median age of 56 years. Two thirds of patients were previously diagnosed with PTC. The presence of other distant metastases was confirmed in less than half of the patients. Only 2 and our patient had immunohistochemical confirmation of PTC metastasis to the sellar region. The presenting signs and symptoms included: visual field defects, ophthalmoplegia, and anterior pituitary hormone deficiencies. In conclusion, this is a rare case of metastatic PTC to the sellar region unequivocally confirmed by immunohistochemistry in whom the disease first presented with a sellar and suprasellar mass.