SS-4 High dose chemotherapy with autologous hematopoietic stem cell transplantation for CNS lymphoma

High-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (HDT-ASCT) is listed as a consolidation therapy option for primary central nervous system (CNS) lymphoma in the guidelines of western countries. The advantages of HDT-ASCT for primary CNS lymphoma as consolidation are believed to be high rates of long-term remission and lower neurotoxicity, even though its eligibility is limited to younger fit patients. In the Japanese guideline, HDT-ASCT for primary CNS lymphoma is however not recommended in daily practice, mainly because thiotepa was unavailable since 2011. The Japanese registry data for hematopoietic transplantation have shown that primary CNS lymphoma patients were treated with various HDT regimens and thiotepa-containing HDT was associated with better progression free survival (P=.019), lower relapse (P=.042) and a trend toward a survival benefit (Kondo E et al, Biol Blood Marrow Transplant 2019). A pharmacokinetic study of thiotepa(DSP-1958) in HDT-ASCT for lymphoma was conducted in 2017, and thiotepa was approved for HDT-ASCT in lymphoma this March, meaning that optimal HDT regimen for CNS lymphoma is now available in Japan. The treatment strategy of CNS lymphoma needs further development to improve survival and reduce toxicity.