Cord blood transplantation for adult mature lymphoid neoplasms in Europe and Japan.

ABSTRACT

ABSTRACT To clarify the different characteristics and prognostic factors of cord blood transplantation (CBT) in adult patients with lymphoid neoplasms in Europe and Japan, we conducted a collaborative study. Patients aged 18-75 years receiving their first CBT (Europe single CBT, n = 192; double CBT, n = 304; Japan single CBT, n = 1150) in 2000-2017 were analyzed. Fewer patients with Hodgkin lymphoma (Europe vs Japan, 26% vs 5%), and older patients (≥50 years) (39% vs 59%) with a higher refined disease risk index (rDRI) (high-very high 49% vs 14%) were included in the Japanese registry. High-very high rDRI was associated with inferior overall survival (OS) (vs low rDRI, Europe hazard ratio [HR], 1.87; P = .001; Japan HR, 2.34; P < .001) with higher progression/relapse risks. Total body irradiation (TBI)-containing conditioning contributed to superior OS both in Europe (vs TBI-reduced-intensity conditioning [RIC], non-TBI-RIC HR, 1.93; P < .001; non-TBI-Myeloablative conditioning [MAC] HR, 1.90; P = .003) and Japan (non-TBI-RIC HR, 1.71; P < .001; non-TBI-MAC HR 1.50, P = .007). The impact of HLA mismatches (≥2) on OS differed (Europe HR, 1.52; P = .007; Japan HR, 1.18; P = .107). CBT for lymphoid neoplasms, especially in those with high rDRI showed poor outcomes despite all the different characteristics in both registries. TBI should be considered in conditioning regimens to improve these outcomes. The different impacts of HLA mismatches call attention to the fundamental differences among these populations.