High-Dose Chemotherapy for Primary Central Nervous System Lymphoma

Outcomes for primary central nervous system lymphoma (PCNSL) have been improved via intensive immunochemotherapy plus autologous stem-cell transplantation (ASCT) consolidation, although clinicians have been concerned that older patients cannot benefit from this regimen due to underlying comorbidities and treatment-related toxicities. In MARTA, a phase 2, prospective, single-arm, German multicenter trial, researchers investigated the use of CNS-penetrating high-dose therapy and ASCT consolidation in 54 fit patients 65 years or older with newly diagnosed PCNSL. Eligible patients received two cycles of high-dose methotrexate and cytarabine plus rituximab, followed by a conditioning regimen of rituximab, thiotepa, and busulfan and then by ASCT rescue.

In the 51 evaluable patients, the 12-month progression-free survival (the primary endpoint) was 58.8%, but this did not meet the statistical threshold for efficacy. The 1-year overall survival was 80.6% among the 36 patients completing study treatment. At a median follow-up of 23 months, 23 patients (45%) had progression or relapse of disease or had died. Seven deaths occurred during induction and consolidation; three were considered treatment-related.