Molecular Monitoring after Autologous Stem Cell Transplantation and Preemptive Rituximab Treatment of Molecular Relapse; Results from the Nordic Mantle Cell Lymphoma Studies (MCL2 and MCL3) with Median Follow-Up of 8.5 Years.

•Minimal residual disease (MRD) relapse predicts clinical relapse after autologous stem cell transplantation (ASCT) in mantle cell lymphoma.•Continuous MRD negativity predicts favorable outcome.•MRD positivity at first analysis post-ASCT predicts very poor outcome.•Preemptive rituximab therapy converts patients back to MRD-negative.•Preemptive rituximab treatment likely delays clinical relapse.