Isolated Metastatic Hepatocellular Carcinoma Masquerading as a Pituitary Macroadenoma- A Case Report and Review of Literature

Abstract

Hepatocellular carcinoma (HCC) is one of the highly malignant and frequent cancers in the world, with a high incidence of extrahepatic metastasis. However, HCC metastasizing to the brain is rare, and isolated involvement of the pituitary and skull base even more infrequent. Such cases may initially present as pituitary adenomas. Differentiation between primary pituitary tumors and metastatic masses is usually done on the basis of clinical presentations, with adenomas commonly being associated with visual field defects and anterior pituitary dysfunction, whereas metastatic masses usually being accompanied by diabetes insipidus (DI), although few cases of cranial nerves involvement and visual defects being the inital manifestation have been reported. Here we describe an extremely rare incidence of metastatic HCC to the sellar and infrasellar region mimicking a pituitary macroadenoma with initial presentations of diplopia, right eyelid drop, generalised body weakness and severe headache as a result of intracerebral bleed with compression of the right 3rd cranial nerve. There were no other signs and symptoms suggesting liver being the primary tumor site. Magnetic resonance imaging (MRI) of the brain was suggestive of a pituitary macroadenoma and the patient subsequently underwent endoscopic decompression and biopsy of the mass. Histopathology and immunohistochemistry (IHC) of the tumor were diagnostic of metastatic HCC. Follow up investigations revealed the primary liver tumor with no other sites of metastasis. The patient was put on Sorafenib followed by whole brain radiation therapy (WBRT), which resulted in transient improvement, but eventually he succumbed to his rapidly progressive disease.