Abstract: Primary central nervous system lymphoma (PCNSL) is a rare tumor involving only the central nervous system. The lesions are mostly single in patients with normal immune function,  but often multiple in patients with immunodeficiency. This article reports  a case of subacute lymphoma of the central nervous system with normal immune function and rare bilateral symmetrical lesions of the frontal lobe and corpus callosum.

Key words: Lymphoma, , Bcell, central nervous system, symmetrical lesions