James L. Rubenstein, University of California, San Francisco, US, provides the Lymphoma Hub with his expert opinion on the role of autologous stem cell transplantation (ASCT) in treating primary central nervous system (CNS) lymphoma. This video addresses a key question within the field; what is the optimal consolidation strategy following induction? The consensus strategy currently, following methotrexate-based induction, is whole-brain radiotherapy. However, there is increasing recognition of neurotoxicity and insufficient long term survival. Two major randomized phase II trials have now been completed which evaluated high dose chemotherapy and ASCT as consolidation. James L Rubenstein discusses both of these, concluding ASCT is superior in relation to event-free survival and neuro-cognitive endpoints. Another issue addressed by James L Rubenstein is the aging population, who are not ideal candidates for whole-brain radiation or ASCT. In this population, low dose lenalidomide maintenance has been shown to penetrate the CSF, is tolerable and patients have achieved long-term remissions in a phase I trial.