Carcinoid tumor of the lung metastatic to a previously identified pituitary adenoma.

The authors present the case of a 58-year-old gentleman presenting with atypical carcinoid tumor of primary lung origin metastasizing to a previously identified pituitary macroadenoma. The patient presented with symptoms of headache and visual disturbance. Imaging revealed enlargement of a known sellar mass as well as three separate enhancing lesions in the brain parenchyma. Resection was accomplished via a transnasal transshpenoidal approach without complication. Immunoreactivity was demonstrated to synaptophysin, chromogranin, CD56, epithelial membrane antigen, and thyroid transcription factor-1. The specimen was also marked by negative staining for pituitary hormones. This case demonstrates a rare occurrence of metastastic spread of tumor to a previously identified pituitary macroadenoma.