Hyperprolactinemia due to pituitary metastasis: A case report.

Background: Pituitary metastasis is an uncommon manifestation of systemic malignant tumors. Moreover, hyperprolactinemia and overall hypopituitarism caused by metastatic spread leading to the initial symptoms are rare.

Case Summary: A 53-year-old male patient was admitted to our hospital with complaints of bilateral blurred vision, dizziness, polyuria, nocturia, severe fatigue and somnolence, decreased libido, and intermittent nausea and vomiting for more than 6 mo. During the last 7 d, the dizziness had worsened. Laboratory investigations revealed overall hypofunction of the pituitary gland, but the patient had an elevated serum prolactin level (703.35 mg/mL). Preoperative magnetic resonance imaging revealed a tumor in the sellar region, accompanied by intratumoral hemorrhage and calcification. Thus, transnasal subtotal resection of the lesion in the sellar region was performed. The histopathological and immunohistochemical examinations of the resected lesion revealed metastasis of lung adenocarcinoma to the pituitary gland. Oral hydrocortisone (30 mg/d) and levothyroxine (25 mg/d) were given both pre- and postoperatively. Post-operatively, the clinical symptoms were significantly improved. However, 4 mo following the surgery, the patient succumbed due to multiple organ failure.

Conclusion: Hyperprolactinemia is one of the markers of poor prognosis in patients with carcinoma that metastasizes to the pituitary gland. Exogenous hormone supplementation plays a positive role in relieving the symptoms of patients and improving quality of life.