Upfront autologous stem cell transplantation for untreated diffuse large B cell lymphoma patients in rituximab era: a systematic review and meta-analysis.

To assess the survival outcomes and adverse events (AEs) of high-intermediate- or high-risk patients with diffuse large B cell lymphoma (DLBCL) who underwent conventional chemotherapy plus rituximab with or without first-line autologous stem cell transplantation (ASCT). Related studies published on Medline, Embase, Cochrane Library, and Web of science were searched, comprising both retrospective and randomized clinical trials (RCTs). The primary endpoints were overall survival (OS) and progression-free survival (PFS). The meta-analysis was performed using the software RevMan v5.3. Four RCTs and six retrospective trials with a total of 1811 patients were identified. Pooled data indicated that conventional chemotherapy plus rituximab followed by ASCT as the first-line therapy contributed to better PFS (HR = 0.73, 95% CI 0.62-0.86, p = 0.0002) but did not significantly improve OS (HR = 0.74, 95% CI 0.55-1.01, p = 0.06) of high-intermediate/high-risk patients. Subgroup analyses of patients with complete remission after induction chemotherapy may benefit from the upfront ASCT (OS, HR = 0.48, 95% CI 0.28-0.82, p = 0.008). The incidences of grade ≥ 3 hematological and non-hematological AEs occurred more frequently in the transplantation group. High-intermediate or high-risk untreated patients with DLBCL only achieved short-term survival benefit with the upfront ASCT.