90Y-Ibritumomab Tiuxetan consolidation after autologous stem cell transplantation improves survival of patients with intermediate-/high-risk diffuse large B-cell lymphoma not responding adequately to first-line treatment.

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma entity whose prognosis for high-risk patients is poor. Aggressive salvage treatments to improve patient outcome have been unsatisfactory. Therefore, we evaluated the efficacy of yttrium-90-ibritumomab tiuxetan (Zevalin (R); Y-90-IT) consolidation after early salvage chemotherapy with autologous stem cell transplantation. Thirty-seven patients with intermediate-high risk DLBCL not in complete remission (CR) after three cycles of rituximab, cyclophosphomide, doxorubicin, vincristine and prednisone (R-CHOP) were assessed retrospectively. After early salvage treatment, 70% achieved CR and 30% partial remission. Twenty patients underwent additional consolidation with Y-90-IT. During the 3-year follow-up, 50% in the Y-90-IT-treated group experienced relapse compared to 82.3% in the other cohort (p=0.002). Progression-and disease-free survival were significantly longer in the Y-90-IT group. However, probably due to the relatively short follow-up period, no difference in overall survival was observed. Y-90-IT consolidation after early salvage chemotherapy improves treatment responses and reduces the percentage of relapses without significant additional toxicities.