Risk of non-Hodgkin lymphoma subtypes in HIV-infected people during the HAART era

OBJECTIVE: HIV-infected people have greatly elevated risk of non-Hodgkin lymphoma (NHL), particularly the AIDS-defining NHL subtypes: diffuse large B-cell lymphoma, Burkitt lymphoma and primary lymphomas arising in the central nervous system. The goals of this analysis were to comprehensively describe risks of NHL subtypes, especially those not well studied, among HIV/AIDS patients; examine risks specifically in the HAART era; and distinguish risks in HIV-infected individuals prior to diagnosis with AIDS. DESIGN: Population-based registry linkage study. METHODS: We used data from the US HIV/AIDS Cancer Match Study from 1996 to 2010 (N = 273 705) to calculate standardized incidence ratios (SIRs) comparing subtype-specific NHL risks in HIV-infected people to those in the general population, and used Poisson regression to test for differences in SIRs between the HIV-only and AIDS periods. RESULTS: NHL risk was elevated 11-fold compared to the general population, but varied substantially by subtype. AIDS-defining NHL subtypes comprised the majority, and risks were high (SIRs ≥17), but risks were also increased for some T-cell lymphomas (SIRs = 3.6-14.2), marginal zone lymphoma (SIR = 2.4), lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (SIR = 3.6), and acute lymphoblastic leukemia/lymphoma (SIR = 2.4). CONCLUSION: HIV-infected people in the HAART era continue to have elevated risk of AIDS-defining NHL subtypes, highlighting the contribution of moderate and severe immunosuppression to their cause. Whereas non-AIDS-defining subtypes are much less common, immunosuppression or other dysregulated immune states likely play a role in the cause of some T-cell lymphomas, marginal zone lymphoma, lymphoplasmacytic lymphoma/Waldenström macroglobulinemia, and acute lymphoblastic leukemia/lymphoma.