R-High-CHOP/CHASER/LEED with Autologous Stem Cell Transplantation in Newly Diagnosed Mantle Cell Lymphoma: JCOG0406.

Although induction immunochemotherapy including high-dose cytarabine and rituximab followed by high-dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) is recommended for younger patients (65 years old) with untreated mantle cell lymphoma (MCL), no standard induction and HDC regimen has been established. We conducted a phase II study of induction immunochemotherapy of R-High-CHOP/CHASER followed by HDC of LEED with ASCT in younger patients with untreated advanced MCL. Eligibility criteria included untreated MCL, stage II bulky to IV, and age 20-65 years. Patients received 1 cycle of R-High-CHOP followed by 3 cycles of CHASER every 3 weeks. Peripheral blood stem cells (PBSC) were harvested during CHASER. LEED with ASCT was delivered to patients who responded to R-High-CHOP/CHASER. Primary endpoint was 2-year progression-free survival (PFS). From June 2008 to June 2012, 45 patients (median age 59 years; range 38-65 years) were enrolled. PBSC were successfully harvested from 36 of 43 patients. Thirty-five patients completed ASCT. Two-year PFS was 77% (80% CI 68-84), which met the primary endpoint. Five-year PFS and overall survival were 52% (95% CI 34-68%) and 71% (95% CI 51-84%), respectively. Overall response and complete response rates after induction immunochemotherapy were 96% and 82%, respectively. The most common grade 4 toxicities were hematological. In younger patients with untreated MCL, R-High-CHOP/CHASER/LEED with ASCT showed high efficacy and acceptable toxicity, and it can now be considered a standard treatment option.