Primary CNS lymphomas are rare neoplasms with poor prognosis compared to other extranodal lymphomas.90% of primary CNS lymphomas are of B cell origin, predominantly of diffuse large B cell type and remaining 10% are poorly characterized low grade lymphomas, Burkitt lymphomas and T cell lymphomas. PCNSL accounts for 1-2 % of malignant brain tumors and 2-4% of all extranodal lymphomas. It can affect any age group but its occurrence in chidren is rare. We report a case of 42 years old male with headache and gradual decrease of vision as the only complaint. MRI scan revealed single intraparenchymal solid enhancing lesion of frontal and left lateral temporal lobe Surgical excision and biopsy showed diffuse large cell lymphoma with a B cell phenotype in IHC. Patient was screened for generalised and deep seated lymphadenopathy. CT Scan and MRI showed no enlarged lymphadenopathy. So a diagnosis of PCNSL was rendered which was further confirmed by IHC.
