Primary Central Nervous System T-cell Lymphoma Associated With Hepatitis B and D Virus Coinfection.

Primary central nervous system lymphoma (PCNSL) is a rare type of non-Hodgkin's lymphoma. It is defined as lymphoma of the central nervous system without any systemic disease elsewhere at the time of diagnosis. Based on the phenotypical features, it is divided into two categories, B-cell and T-cell, with the latter being less common.