Impact Of Total Therapies On Clinical Outcome Of Myeloma Stratified By Risk And Molecular Subgroups.

8586 Background: Despite the introduction of new agents multiple myeloma (MM) is a disease with unpredictable clinical course consistent with it being composed of a variety of subtypes with distinct molecular features. In order to shed light on the impact of this molecular heterogeneity on treatment response we examined clinical outcomes in our series of Total Therapy (TT) trials, stratified by risk status and molecular subgroup. Methods: We included 1318 patients with available baseline gene expression profiling (GEP) data enrolled on Total Therapy 2–5, stratified by GEP70-defined risk and molecular subgroup. We analyzed their effect on outcomes and timing of treatment failure in relation to protocol phase. Results: For GEP70-defined low risk (LR) MM, PFS and OS has incrementally improved with addition of thalidomide in TT2 and bortezomib (Bz) in TT3a and 3b. While Bz improved outcomes for LRMM within the MS molecular subgroup, it had no significant impact on MF cases. Outcomes for patients treated on TT...