New treatment strategies for primary central nervous system lymphoma

Purpose of review To summarize recent treatment strategies for primary central nervous system lymphoma (PCNSL) and present the new avenues for this rare and aggressive disease. Recent findings The current induction regimens based on high-dose methotrexate (HD-MTX) give similar and still insufficient response rates. Intensive consolidation with autologous stem cell transplantation has become the standard of care for eligible responder patients, while conventional whole brain radiotherapy has been abandoned due to irreversible treatment-related neurotoxicity. Maintenance treatment is being assessed for elderly and frail patients. Efforts are being made to improve the outcome after induction, mainly by adding targeted therapy to standard HD-MTX-based chemotherapy. A better understanding of PCNSL biology will optimize the use of targeted therapies based on the characteristics of the lymphoma cells and the tumor microenvironment. Preliminary results of chimeric antigen receptor T cells are encouraging. Cytokines or circulating tumor DNA are emerging as strong complementary tools to neuroimaging. Summary Outcome of fit patients has improved with intensive consolidation. New avenues include maintenance strategies for elderly and frail patients, targeted induction treatment, modern immunotherapies, and new drug-delivery modalities. Risk stratification and dynamic response assessment are necessary to design and evaluate personalized and response-driven treatment strategies.