A pooled analysis of 1,546 patients with AIDS-related lymphoma (ARL): An assessment of prognostic factors by treatment era.

Abstract

8524 Background: Management of ARL evolved in the last 2 decades. We previously reported prognostic factors in a pooled analysis of 1,546 patients with ARL, and here present analysis of these factors over time to determine if their prognostic significance has changed. Methods: Following a systematic review, we assembled individual patient data from 19 prospective phase 2/3 clinical trials (published 1993-2010) for ARL (n=1,546). Factors analyzed include age, sex, histology, CD4 count, prior history of (h/o) AIDS, & age-adjusted (aa) IPI. The endpoint was overall survival (OS) expressed as the hazard ratio (HR) for death. We used separate Cox proportional hazard models adjusted for the other covariates to determine the significance of each variable in the following time periods: pre-cART [combination antiretroviral therapy] (<1996; n=388), early cART (‘96-‘00; n=694), modern cART (‘01-‘04; n=282) & current era (‘05-‘10; n=182). We also combined all enrollments in one Cox model to test for difference in association with OS over enrollment periods. Results: Rituximab use was limited in the early cART (20%) compared with the modern cART (83%) and current (93%) eras. Histology & sex were not significantly associated with OS in any time period. Increasing age was associated with worse OS in the pre-cART (HR 1.02; p<0.01) and current (HR 1.05, p=0.04) eras. A prior h/o AIDS increased risk of death during early cART (HR 1.31, p=0.047) but was not significant after 2000. Meanwhile, baseline CD4 count <50 was a poor prognostic factor during early (HR 1.78, p<0.01) and modern cART (HR 2.76, p=0.001) eras, but not in the current era. The aaIPI predicted worse OS in each time period (pre-cART: HR 1.54, p<0.0001; early cART: HR 1.49, p<0.0001; modern cART: HR 1.52, p<0.01; current era: HR 2.34, p<0.0001). No significant interaction between each prognostic factor with enrollment was found. Conclusions: In this pooled analysis of 1,546 patients with ARL, aaIPI was the only consistently significant prognostic factor and its effect was magnified in the current era. HIV-related factors gained prognostic relevance in the early and modern cART era but may not be as relevant with current treatment strategies.