[Nervous system lymphoma in HIV infection].

Primary CNS lymphoma is recognized as one of the criteria of AIDS. The incidence is 0.4 to 0.56% of AIDS complications. Non-Hodgkin's lymphomas appear as multicentric tumours, mostly located in the hemispheres; they have a B phenotype and have a high grade of malignancy. They are sometimes associated with opportunistic infections. Survival is around 4 to 5 months. The presence of EBV in these tumours is an argument to propose a synergistic role of this virus in the pathogenesis of these tumours. Secondary lymphomas are observed in 40 to 47% of these tumours and must be systematically looked for. Hodgkin's disease is rare. It is mostly diagnosed as secondary compressive epidural tumors.