Central nervous system relapse in younger patients with diffuse large B-cell lymphoma: a LYSA and GLA/DSHNHL analysis.

Most patients with diffuse large B-cell lymphoma (DLBCL) can be cured with immunochemotherapy such as R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). Patients with progression or relapse in the central nervous system (CNS) face dismal outcomes. The impact of more aggressive regimens used in frontline therapy has not been systematically investigated in this context. To this end, we analyzed a large cohort of 2203 younger patients with DLBCL treated on 10 German (German Lymphoma Alliance [GLA]/The German High Grade Non-Hodgkin's Lymphoma Study Group [DSHNHL]) and French (The Lymphoma Study Association [LYSA]) prospective phase 2 and 3 trials after first-line therapy with R-CHOP, R-CHOEP (R-CHOP + etoposide), dose-escalated R-CHOEP followed by repetitive stem cell transplantation (R-MegaCHOEP), or R-ACVBP (rituximab, doxorubicin, cyclophosphamide, vindesine, bleomycine, and prednisone) followed by consolidation including multiple drugs crossing the blood-brain barrier (BBB). Patients with DLBCL with an age-adjusted International Prognostic Index (aaIPI) of 0 to 1 showed very low cumulative incidence rates of CNS relapse regardless of first-line therapy and CNS prophylaxis (3-year cumulative incidences 0%-1%). Younger high-risk patients with aaIPI of 2 to 3 had 3-year cumulative incidence rates of 1.6% and 4% after R-ACVBP plus consolidation or R-(Mega)CHO(E)P, respectively (hazard ratio 2.4; 95% confidence interval: 0.8-7.4; P = .118). Thus, for younger high-risk patients, frontline regimens incorporating agents crossing the BBB may reduce often fatal CNS relapse.