Differences in outcome for consecutive patients with diffuse large B-cell lymphoma before and after the advent of rituximab: A single-center experience

The beneficial effect of rituximab for first-line treatment of diffuse large B-cell lymphoma (DLBCL) has been demonstrated by several randomized controlled trials. To clarify whether results for selected patient populations also apply to unselected patients, we analyzed long-term outcomes for all the 277 consecutive adults diagnosed with de novo DLBCL in a single center between 1998 and 2008. The study population included 147 and 130 patients diagnosed before (Cohort A) and after the advent of rituximab (Cohort B). Progression-free survival (PFS) was significantly better for Cohort B than for Cohort A (P = 0.005). For patients age 60 or younger, PFS did not differ significantly between Cohort A and Cohort B (P = 0.329), but for patients over 60, Cohort B showed superior PFS (P = 0.002). Patients with high or high-intermediate risk according to the International Prognostic Index score showed less improvement in PFS than did those with low or low-intermediate risk primarily because of still unfavorable outcomes of patients with poor performance status. These results indicate that the advent of rituximab has significantly improved outcome for unselected patients with DLBCL, and that improvement was greater for older patients. Further investigations are warranted in the hope of improving outcomes for younger patients with DLBCL.