Outcomes after 90Yttrium-ibritumomab tiuxetan-BEAM in diffuse large B-cell lymphoma: a meta-analysis

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is a standard therapy in patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) who are chemosensitive. The combination of carmustine, etoposide, cytarabine, and melphalan (BEAM) is commonly used as a conditioning regimen. The addition of yttrium-90 ((90) Y)-ibritumomab tiuxetan (Zevalin(®)) to BEAM (Z-BEAM) is increasingly being used to improve outcomes and overcome refractory disease. We conducted a literature review and meta-analysis in order to evaluate the clinical effects of Z-BEAM followed by ASCT in patients with DLBCL. A literature search was conducted for randomized controlled trials and observational studies of Z-BEAM as a conditioning regimen for ASCT in adult patients with DLBCL. Extracted data included baseline patient demographics, overall response (ORR), complete response (CR), overall survival (OS), progression-free survival (PFS), nonrelapse mortality (NRM), median time to ANC and platelet engraftment, and rate of myelodysplastic syndrome. Mixed-effects models were used to determine estimates. Ten studies (N = 328) were included in the meta-analysis. The 2-year OS and PFS were 84.5% (n = 328) and 67.2% (n = 285), respectively. Outcomes were superior in patients with nontransformed lymphoma. Posttransplant, ORR and CR rates were 72.6% and 68.5%, respectively. The NRM rate was 6.3% and the incidence rate of myelodysplastic syndrome was 2.5%. Two-year OS was significantly associated with pretransplant ORR (P = 0.008, τ(2) = 0). There was no significant association between PFS and pretransplant response. Z-BEAM is safe and effective as a conditioning regimen in relapsed/refractory DLBCL.