[Primary cerebral lymphoma in AIDS. Retrospective study of 20 patients].

Objectives: Analyze the epidemiological pattern of primary central nervous system lymphoma in AIDS patients together with the clinical expression and course under treatment.

Methods: We retrospectively reviewed 20 patients with AIDS-associated primary central nervous system lymphoma hospitalized in our unit between April 1992 and July 1996. Diagnosis was considered probable when an expansive intracranial process was associated with CT-scan enhancement and antitoxoplasma therapy failure in patients with extraneurological localization. Diagnosis was considered to be certain after histological confirmation.

Results: Most-patients were male (19/20), with a median CD4 cell count of 9/mm3 (range 0-138). Ninety percent had AIDS before diagnosis. The presenting symptoms were mental status changes (70%), neurologic deficits (55%), fever without another cause (30%), increased intracranial pressure (25%) or seizures (25%). Opportunistic diseases were usually associated (60%). CT-scan (18/20) showed spontaneous iso or hyperdense lesions, most often solitary (67%), with nodular contrast enhancement (72%). When performed (7/20), magnetic resonance imaging showed hypointense lesions on T1-weighted images with marked contrast enhancement. Diagnosis of primary central nervous system lymphoma was suspected in 19 patients because of the failure of antitoxoplasma treatment; 4 patients had stereotactic biopsy which confirmed the diagnosis. Patients were treated with either total brain radiation therapy (10%), corticosteroids (30%), or both (60%). The median survival time after onset of symptoms was better with combined therapy or radiation therapy alone than with steroids alone (6 vs. 2 months). Interestingly, most of the patients died from neurological complications of lymphoma (85%).

Discussion: The frequency of lymphoma-related death is probably due to better management of opportunistic infections and the effect of antiretroviral therapy. Further studies combining antiretroviral therapy, radiation and chemotherapy in patients with good performance status should be considered to improve the poor prognosis of AIDS-associated primary central nervous system lymphoma.