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

Tumors in general metastasizing to the pituitary gland and skull base are a rare occurrence, comprising of 1-3% of all pituitary masses [1]. Moreover, breast and lung tumors are the commonest primary malignancies that result in pituitary gland metastasis, with a pituitary mass often being the first manifestation of an occult primary tumor [2]. HCC is a frequently occurring malignancy usually manifesting in the 6th and 7th decade of life, with about 64% cases demonstrating extrahepatic metastasis [3]. The commonest sites of HCC metastasis include the lungs, regional lymph nodes, kidney, bone marrow and adrenals [3,4]. However, brain metastasis is infrequent. Moreover, pituitary and skull base metastasis of HCC has rarely been reported in literature, especially without involvement of any other site. Such isolated cases of pituitary metastasis may closely mimic a pituitary adenoma, however, they usually manifest primarily with DI. Differentiation between a metastatic mass and a pituitary adenoma is usually done on the basis of such clinical presentations where pituitary adenomas are usually associated with visual field defects and anterior pituitary dysfunction, as opposed to DI being the primary presentation of symptomatic metastasis [1,5]. However, few cases of pituitary and skull base metastasis have been reported in literature which initially presented with features cranial nerve palsies [1,6], visual field defects [7] and hypopituitary symptoms including panhypopituitaris [8]. Nevertheless, majority of such metastatic tumors are clinically silent or too small to be diagnosed radiologically. Moreover, when symptomatic, they may have varied clinical and radiological presentations such as tumors, abscesses, cysts, aneurysms, granulomas, trauma or apoplexy; making it difficult to distinguish them from other sellar area lesions [2]. The deceptive nature of these metastatic lesions is particularly of significance when there is no clinical evidence of the primary disease, with neurological or endocrinal symptoms being the only manifestation. In such cases, it is essential to correctly diagnose these lesions in order to plan appropriate management strategies. Our case describes that of a 62 year man with isolated cranial metastatic HCC who initially presentated with 3rd cranial nerve palsy, severe headache, and generalized weakness with no Volume 5 Issue 5 2016