Primary lymphoma of the pituitary gland: an unusual cause of hemianopia in an immunocompetent patient

Primary central nervous system lymphoma (PCNSL) is an uncommon form of non-Hodgkin's lymphoma that can affect any part of the brain or spinal cord. The progressive refinement of endocrine tests, as well as improvements in and increasing availability of diagnostic imaging, has led to an increasing number of pituitary masses being diagnosed.1,2 In addition, with the appearance of acquired immunodeficiency syndrome (AIDS) and organ transplantation in the last 30 years, the incidence of central nervous system (CNS) lymphoma is thought to have increased.2 Recent improved survival rates of patients with AIDS have led to a further increase in primary CNS lymphoma (PCNSL), with an estimated 2.5% of patients with AIDS developing PCNSL.3 PCNSL of the pituitary gland is an extremely rare form of this disease. In this article we report the case of an immunocompetent patient who presented with hemianopia and headache secondary to a large primary lymphoma of the pituitary gland which was initially thought to represent an inoperable and incurable tumour. A review of other reported cases is presented to establish common features of the disease.