Pituitary gland metastasis from renal cell carcinoma presented as a non-functioning macroadenoma

Metastatic tumors involving the pituitary gland are an uncommon finding and occur in up to 1% of all pituitary tumor resections. A 74-year-old man had progressive vision deterioration, over the 30 days prior to consultation. He did not complain of headache or polyuria, but referred to intestinal constipation. Five years ago, he underwent a right radical nephrectomy for renal cell carcinoma, followed by chemotherapy and radiotherapy for lung and parotid metastases. On ophthalmologic examination, there was a left abducens nerve palsy and bitemporal hemianopia. Magnetic resonance imaging demonstrated a sellar mass with suprasellar cistern extension compressing the optic chiasm. Endocrinological evaluation revealed central adrenal and gonadal insufficiencies. The patient underwent a transsphenoidal tumor resection that revealed renal cell carcinoma. This case illustrates that metastatic pituitary lesions can mimic typical symptoms and signs of pituitary macroadenoma. Furthermore, clinical diabetes insipidus, a common finding of pituitary metastases, can be absent.