Metastasis of lung adenocarcinoma to the pituitary gland

Pituitary metastasis (PM) is rare occurrence and accounts for <1% of all intracranial metastatic lesions. In this study, we highlight the importance of considering atypical sites for lung adenocarcinoma metastasis by presenting a case of a 54-year-old male who was diagnosed with PM 15 months after being diagnosed with stage IV lung adenocarcinoma with metastasis to the spine, pelvis, left frontal lobe, and right occipital lobe. He was on a prolonged course of chemotherapy during those 15 months and received palliative radiation for his brain metastasis with subsequent remission after 5 months following his initial diagnosis. The pituitary lesion was picked up as an incidental finding on a routine staging magnetic resonance imaging (MRI) 10 months after his brain metastasis remission. The patient successfully underwent trans-sphenoidal pituitary lesion resection. This case emphasizes the importance of routine surveillance and examination of atypical sites of metastasis even in patients undergoing a prolonged course of chemotherapy.