This chapter discusses the pathology and management options of primary central nervous system lymphoma (PCNSL) with brief note on our experience. PCNSL refers to extranodal lymphoma; DLBCL is the most common. By definition, the brain parenchyma, the eye, the meninges, the spinal cord and the cranial and spinal nerve roots may be involved. Pathogenesis is not known; immunocompromised status and EBV have been implicated. Surgery is for diagnosis. Primary central nervous system lymphomas also known as \"ghost or vanishing tumor\" due to the complete spontaneous clinical and radiological remission. Corticosteroids alone can cause tumor regression in 40% of cases. Current trend is toward both avoiding WBRT altogether and reserving it for chemotherapy-resistant cases and chemotherapy-resistant relapses, or to give low-dose irradiation to improve the neurocognitive results as well as OS.