Risk-adapted intensive induction therapy, autologous stem cell transplantation, and rituximab maintenance allow to reach a high 7-year survival rate in patients with mantle cell lymphoma

Abstract

Mantle cell lymphoma (MCL) is aggressive B-cell neoplasm diagnosed predominantly among older men. R-CHOP-like regimens allow to achieve high response rate, but the overall survival (OS) are disappointingly short - 3-4 years. An addition of high-dose cytarabine to the upfront therapy and autoSCT significantly improved outcomes but remain feasible largely for medically fit patients. Based on the activity and good tolerance of gemcitabine-oxaliplatin schemes in relapsed and refractory MCL patients, we developed an alternative first-line course for patients who are not eligible for R-HD-MTX-AraC. Aim. Assess toxicity and efficacy of R-DA-EPOCH/ R-HD-MTX-AraC and R-DA-EPOCH/R-GIDIOX schemes, autoSCT and R-maintenance in untreated MCL patients. Materials and methods. 47 untreated MCL patients from 6 centers were enrolled in prospective study between April 2008 and September 2013. All patients have stage II-V; ECOG 0-3; median age 55 years (29-64); Male/Female 76%/24%. MIPIb: 28% low, 33% intermediate and 39% high risk. Following 1st R-EPOCH patients were assigned to receive either R-DA-EPOCH/ R-HD-MTX-AraC or R-DA-EPOCH/ R-GIDIOX regimen. In the absence of renal failure, hematological toxicity grade 4 more than 3 days and severe infections patients received R-HD-MTX-AraC scheme (R 375 mg/m2 Day 0, Methotrexate 1000 mg/m2/24 hours Day 1, AraC 3000 mg/m2 q 12 hrs Days 2-3). Patients who had at least one of these complications received R-GIDIOX scheme (R 375 mg/m2 day 0, gemcitabine 800 mg/m2 days 1 and 4, ifosfamide 1000 mg/m2 days 1-5, dexamethasone 10 mg/m2 IV days 1-5, irinotecan 100 mg/m2 day 3, oxaliplatin 120 mg/m2 day 2). Subsequently these courses were alternating with R-DA-EPOCH in each arm of the protocol. Depending on the time of achieving CR patients received 6 or 8 courses, unless they progressed on therapy. Those patients who achieved PR/CR/CRu underwent autoSCT (BEAM-R). Posttransplant R-maintenance was administered for 3 years (R - 375 mg/m2 every 3 months). Results. 29/47 patients were treated on R-HD-MTX-AraC arm (median 50 years; MIPIb: 35.7% low, 28.6% intermediate, 35.7% high risk) and 18/47 patients were on R-GIDIOX arm (median 60 years; MIPIb: 16.7% low, 38.9% intermediate, 44.4% high risk). In R-HD-MTXAraC arm CR rate was 96.5%. In R-GIDIOX arm OR and CR rates were 94.4% and 77.7% respectively. Main hematological toxicity of R-GIDIOX was leukopenia gr. 4 occurred in 74.1%. With median follow-up of 76 months, the estimated 7-years OS and EFS in R-HD-MTXAraC arm are 76% and 57% respectively. In R-GIDIOX arm the estimated 7-years OS and EFS are 59% and 44%, respectively. There are no statistical differences in EFS (p=0.47) and OS (p=0.06) between two arms. Conclusions. The use of a risk-adapted strategy allowed 95.7% of patients achieve PR/CR/CRu, performed autoSCT and begun R-maintenance therapy with rituximab. None of the patients needed a premature discontinuation of therapy because of unacceptable toxicity. The performance of autoSCT and R-maintenance apparently allowed to partially offset differences in the intensity of induction therapy and to maintain comparable results of therapy in both induction arms.