Primary Central Nervous System B Cell Lymphoma, Unclassifiable, in an Immunocompetent Young Male

Abstract

Background: Primary CNS B cell lymphoma, unclassifiable with features intermediate between diffuse large B cell lymphoma and Burkitt's lymphoma (DLBCL/BL) in an immuno-competent young boy is a rare entity. Case Report: A 14 year old boy presented with headache and vomiting. CT brain showed well-defined mildly enhancing hyperdense lesion in left intra-ventricular region with seeding in the temporal lobe and the supra-sellar region suggesting a neoplastic condition. Squash cyotology of specimen after tumor decompression suggested high grade non-Hodgkin's lymphoma. Tissue paraffin sections showed tumor cells diffusely positive for CD20, BCl6, and BCl2, focally positive for CD10 and negative for Tdt on immunohistochemistry. Mib1 index was nearly 100%. In view of high Mib 1 index and strong Bcl2 positivity and in the absence of disease elsewhere in the body on PET CT, a diagnosis of primary CNS B cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL was given. Conclusion: Primary CNS B cell lymphoma, unclassifiable, with features intermediate between DLBCL and BL can also occur in young immuno-competent patients. Though rare, these lymphomas are also known to occur in the central nervous system.