The clinical features and laboratory results of 63 patients with or at risk for AIDS with lymphoid neoplasias seen from November 1980 through November 1986 are reviewed. Forty-three had systemic non-Hodgkin's lymphoma (NHL), nine had primary large cell lymphomas of the brain, 11 had Hodgkin's disease (HD), and one had plasmacytoma evolving to myeloma. Those with systemic NHL included 40 (93%) with intermediate or high-grade histologies, 35 (81%) with advanced stage (III, IV), and 28 (65%) with extranodal disease at presentation (predominantly marrow and meninges). Overall survival was short (median, 10.5 months from diagnosis) with the majority of deaths attributable to AIDS-related opportunistic infections (OI). However, 17 patients with diffuse NHL achieved a complete clinical remission, and nine now have been disease-free for more than 1 year (median follow-up, 28 months; range, 12 to 73 months). Early stage and lack of systemic symptoms were features associated with prolonged disease-free survival. Primary brain NHL was a uniformly lethal manifestation of AIDS, being diagnosed at postmortem in seven of nine severely immunosuppressed homosexual men. As with NHL, a propensity towards advanced disease and extranodal involvement was also observed in HD, suggesting that the atypical clinical behavior of HD may be an additional epiphenomenon of AIDS. This experience tends to argue for the use of intensive therapy in at least some patients with AIDS-related systemic NHL since it has resulted in a proportion of long-term disease-free survivors.