In immunocompetent patients The initial response to radiotherapy is often excellent, and may result in a complete remission. However, the duration of response with radiotherapy alone remains short, with median survival after treatment with radiotherapy just 18 months. Methotrexate based chemotherapy markedly improves survival, with some studies showing median survival after methotrexate chemotherapy reaching 48 months. In AIDS patients Patients with AIDS and<unk>  have a median survival of only 4 months with radiotherapy alone. Untreated, median survival is only 2.5 months, sometimes due to concurrent opportunistic infections rather than the<unk>  itself. Extended survival has been seen, however, in a subgroup of AIDS patients with CD4 counts of more than 200 and no concurrent opportunistic infections, who can tolerate aggressive therapy consisting of either methotrexate monotherapy or vincristine, procarbazine, or whole brain radiotherapy. These patients have a median survival of 10–18 months. Of course, highly active antiretroviral therapy (HAART) is critical for prolonged survival in any AIDS patient, so compliance with HAART may play a role in survival in patients with concurrent AIDS and<unk> .
Primary central nervous system lymphoma
Malignant multiple sclerosis
Lymphocytic meningoradiculitis
Leptomeningeal cancer
Brainstem glioma
Brain metastasis
Central nervous system cavernous hemangioma
Autoimmune encephalitis