Open-label, single arm, multicenter phase II study of VIDL induction chemotherapy followed by upfront autologous stem cell transplantation in patients with advanced stage extranodal NK/T-cell lymphoma.

The clinical outcome of advanced-stage Extranodal NK/T cell lymphoma (ENKTL) patients using conventional chemotherapy is extremely poor. The aim of this study was to investigate the outcomes of advanced-stage ENKTL patients treated with non-anthracycline-based chemotherapy followed by upfront autologous stem cell transplant (ASCT). From 8 institutions, 27 patients were recruited from February 2016 to May 2019. Patients were treated with 4 cycles of VIDL induction chemotherapy. Patients who achieved complete response (CR) or partial response (PR) underwent upfront ASCT. This study is registered with clinicaltrial.gov, # NCT02544425. Twenty patients (74.1%) completed 4 cycles of VIDL induction. The overall response rate of VIDL was 74.1%, including 17 (63.0%) with CR and 3 (11.1%) with PR. Primary toxicity of the induction regimen was grade 3 or 4 neutropenia, and no treatment-related mortality was reported. Seventeen patients proceeded with upfront ASCT, and 9 patients relapsed after ASCT, among whom, 4 was central nervous system (CNS) relapse. The median duration of response was 15.2 months (95% CI, 6.3-24.1 months). This study suggested that VIDL induction chemotherapy followed by upfront ASCT is feasible and effective for the treatment of advanced-stage ENKTL. However, CNS relapse prevention is needed in the treatment of advanced-stage ENKTL.