Autologous stem cell transplantation in mantle cell lymphoma: a report from the SFGM-TC

Bendamustine-EAM versus BEAM regimen in patients with mantle cell lymphoma undergoing autologous stem cell transplantation in the frontline setting: a multicenter retrospective study from Lymphoma Study Association (LYSA) centers

The combination of carmustine, etoposide, cytarabine, and melphalan (BEAM) as conditioning regimen prior to autologous stem-cell transplantation (ASCT) remains the standard of care for patients with mantle cell lymphoma (MCL) who are eligible for transplantation. The replacement of carmustine with bendamustine (BeEAM) was described as a promising alternative in non-Hodgkin lymphoma. The aim of this retrospective study was to compare the BeEAM with the BEAM regimen in MCL patients in the frontline setting. Sixty and 108 patients were included in the BeEAM and the BEAM groups, respectively. At 3 years, progression-free survival (PFS) was significantly higher in the BeEAM than in the BEAM group (84% [73-96] vs. 63% [51-79], p = 0.03). The overall survival was not statistically different between the two groups (p = 0.2). In multivariable analysis, BeEAM regimen remained associated with higher PFS (HR = 0.377, 95% CI, 0.146-0.970; p = 0.043). Subgroup analyses in patients treated with prior rituximab-aracytine induction alone showed that BeEAM improved the PFS compared with BEAM regimen (p = 0.04). Despite the high rate of acute renal failure KDIGO III (32%), treatment-related mortality was not increased with the BeEAM regimen. A prospective randomized trial will be necessary to confirm the beneficial effect of the BeEAM regimen in MCL patients undergoing ASCT.

Survival Outcomes of Younger Patients With Mantle Cell Lymphoma Treated in the Rituximab Era

PURPOSE

Mantle cell lymphoma (MCL) is a B-cell lymphoma characterized by cyclin D1 expression. Autologous hematopoietic cell transplantation (AHCT) consolidation after induction chemotherapy is often used for eligible patients; however, the benefit remains uncertain in the rituximab era. Herein we retrospectively assessed the impact of AHCT consolidation on survival in a large cohort of transplantation-eligible patients age 65 years or younger.

PATIENTS AND METHODS

We retrospectively studied transplantation-eligible adults age 65 years or younger with newly diagnosed MCL treated between 2000 and 2015. The primary objective was to assess for improved progression-free survival (PFS) with AHCT consolidation and secondarily to assess for improved overall survival (OS). Cox multivariable regression analysis and propensity score-weighted (PSW) analysis were performed.

RESULTS

Data were collected from 25 medical centers for 1,254 patients; 1,029 met inclusion criteria. Median follow-up for the cohort was 76 months. Median PFS and OS were 62 and 139 months, respectively. On unadjusted analysis, AHCT was associated with improved PFS (75 v 44 months with v without AHCT, respectively; P < .01) and OS (147 v 115 months with v without AHCT, respectively; P < .05). On multivariable regression analysis, AHCT was associated with improved PFS (hazard ratio [HR], 0.54; 95% CI, 0.44 to 0.66; P < .01) and a trend toward improved OS (HR, 0.77; 95% CI, 0.59 to 1.01; P = .06). After PSW analysis, AHCT remained associated with improved PFS (HR, 0.70; 95% CI, 0.59 to 0.84; P < .05) but not improved OS (HR, 0.87; 95% CI, 0.69 to 1.1; P = .2).

CONCLUSION

In this large cohort of younger, transplantation-eligible patients with MCL, AHCT consolidation after induction was associated with significantly improved PFS but not OS after PSW analysis. Within the limitations of a retrospective analysis, our findings suggest that in younger, fit patients, AHCT consolidation may improve PFS.

Paramount therapy for young and fit patients with mantle cell lymphoma: strategies for front-line therapy

The natural history of mantle cell lymphoma (MCL) is a continuous process with the vicious cycle of remission and recurrence. Because MCL cells are most vulnerable before their exposure to therapeutic agents, front-line therapy could eliminate MCL cells at the first strike, reduce the chance for secondary resistance, and cause long-term remissions. If optimized, it could become an alternative to cure MCL. The key is the intensity of front-line therapy. Both the Nordic 2 and the MD Anderson Cancer Center HCVAD trials, with follow-up times greater than 10 years, achieved long-term survivals exceeding 10 years. But the Achilles heel in both trials were the severe toxicities, such as secondary malignancies including myelodysplastic syndromes /leukemia. Therefore, intensive therapies can act as a double-edged sword providing long term survival at the cost of severe toxicities. In our opinion, although intensive chemotherapy can cause detrimental side effects, it is indispensable given that we run the risk of sacrificing long-term survivals in these young and fit patients. We must seek for a powerful alternative at the front-line. Furthermore, minimal residual disease negativity should be the optimal therapeutic goal to achieve before and after autologous stem cell transplantation. Some novel therapeutic strategies have shown to improve outcomes, but it is not yet clear as to how these results translate in population. Of note, MCL patients need to be stratified at diagnosis and be provided with different intensities of front-line regimen. In this review, we discuss current strategies for the treatment of young patients with newly diagnosed MCL.

Total Body Irradiation Is Safe and Similarly Effective as Chemotherapy-Only Conditioning in Autologous Stem Cell Transplantation for Mantle Cell Lymphoma

Autologous stem cell transplant (ASCT) consolidation has become a standard approach for patients with mantle cell lymphoma (MCL), yet there is little consensus on the role of total body irradiation (TBI) as part of high-dose transplantation conditioning. We analyzed 75 consecutive patients with MCL who underwent ASCT at our institution between 2001 and 2011 with either TBI-based (n = 43) or carmustine, etoposide, cytarabine, melphalan (BEAM; n = 32) high-dose conditioning. Most patients (97%) had chemosensitive disease and underwent transplantation in first remission (89%). On univariate analysis, TBI conditioning was associated with a trend toward improved PFS (hazard ratio [HR], .53; 95% confidence interval [CI], .28-1.00; P = .052) and similar OS (HR, .59; 95% CI, .26-1.35; P = .21), with a median follow-up of 6.3 years in the TBI group and 6.6 years in the BEAM group. The 5-year PFS was 66% in the TBI group versus 52% in the BEAM group; OS was 82% versus 68%, respectively. However, on multivariate analysis, TBI-based conditioning was not significantly associated with PFS (HR, .57; 95% CI .24-1.34; P = .20), after controlling for age, disease status at ASCT, and receipt of post-transplantation rituximab maintenance. Likewise, early toxicity, nonrelapse mortality, and secondary malignancies were similar in the 2 groups. Our data suggest that both TBI and BEAM-based conditioning regimens remain viable conditioning options for patients with MCL undergoing ASCT.

Allogeneic stem cell transplantation for patients with mantle cell lymphoma who failed autologous stem cell transplantation: a national survey of the SFGM-TC

Poly-chemotherapy plus rituximab followed by autologous stem cell transplantation (auto-SCT) is standard care for untreated young patients with mantle cell lymphoma (MCL). Despite this intensive treatment, transplant patients remain highly susceptible to relapse over time. The French SFGM-TC performed a national survey on reduced-intensity conditioning allogeneic stem cell transplantation (RIC-allo-SCT) for fit relapsed/refractory patients who failed after auto-SCT (n=106). Median times of relapse after auto-SCT, and from auto-SCT to RIC-allo-SCT were 28 months and 3.6 years, respectively. Sixty per cent of patients received at least three lines of treatment before RIC-allo-SCT. Conditioning regimens for RIC-allo-SCT were heterogeneous. Twenty patients experienced grade III/IV aGvHD, extensive cGvHD was reported in 28 cases. Median follow-up after RIC-allo-SCT was 45 months. Median PFS after RIC-allo-SCT was 30.1 months and median overall survival was 62 months. Treatment-related mortality (TRM) at 1 year and 3 years were estimated at 28% and 32%, respectively. A total of 52 patients died; major causes of death were related to toxicity (n=34) and MCL (n=11). Patients in good response before RIC-allo-SCT experienced a better PFS and OS. Our work highlights the need for new RIC-allo-SCT MCL-tailored approaches to reduce TRM, and early and late relapse.

The role of targeted treatment in mantle cell lymphoma: is transplant dead or alive?

Based on the profound biological insights of the last years into the molecular pathogenesis of mantle cell lymphoma and the clinical introduction of new targeted drugs, with high efficacy and a good safety profile, the therapeutic scenario for this tumor has been shown to be thoroughly favourable. No longer characterized by a uniformly dismal prognosis, mantle cell lymphoma has been revealed as a spectrum of different diseases, ranging from very indolent cases to highly aggressive and refractory ones. Thus, there is an urgent need to adapt therapy to accommodate the diverse presentations of the disease. High-dose chemotherapy, followed by autologous stem cell transplantation is the current standard of care for younger patients, generally providing high responses and long survival rates, but hampered by acute and long-term toxicity. In addition, some patients may be overtreated, while others could benefit from targeted approaches, based on the new, molecular-directed compounds. Such a personalized treatment based on the specific characteristics of individual patients may be guided by validated prognostic tools, such as the Mantle Cell Lymphoma International Prognostic Index and the Ki-67 Proliferative Index, as well as by early predictors of treatment response, like minimal residual disease analysis. Moreover, mutation screening of distinctive genomic alterations may provide new, predictive biomarkers, with an additional impact on clinical practice. Only after tailoring treatment according to the clinical and biological heterogeneity of the disease the role of transplantation and modern therapeutic options will be redefined in mantle cell lymphoma.

Phase II Trial of Tandem High-Dose Chemotherapy with Autologous Stem Cell Transplantation Followed by Reduced-Intensity Allogeneic Stem Cell Transplantation for Patients with High-Risk Lymphoma

Many patients with lymphoma relapse after autologous stem cell transplantation (AutoSCT). These patients are often considered for allogeneic stem cell transplantation (AlloSCT) if remission can be achieved. If a tandem approach was organized, some cases of relapse might be prevented. We conducted a phase II trial of tandem AutoSCT followed by reduced-intensity conditioning (RIC) AlloSCT for patients with high-risk lymphoma. High-dose chemotherapy was given with busulfan, cyclophosphamide, and etoposide. AlloSCT was composed of RIC with busulfan/fludarabine and tacrolimus, sirolimus, and methotrexate as graft-versus-host disease (GVHD) prophylaxis. Donors were fully matched related or unrelated donors. AlloSCT was performed any time between 40 days and 6 months after AutoSCT. Forty-two patients were enrolled, and all patients underwent AutoSCT. RIC AlloSCT was performed in 29 patients. In the 29 patients who underwent tandem transplant, median time from AutoSCT to AlloSCT was 96 days (range, 48 to 169). The 6-month cumulative incidence of grades II to IV acute GVHD was 13.8% (90% confidence interval [CI], 5.3% to 26.3%). Cumulative incidence of chronic GVHD at 1 year was 37.9% (90% CI, 23.1% to 52.7%). Nonrelapse mortality at 2 years after AlloSCT was 11.1% (90% CI, 3.5% to 23.6%). At a median follow-up of 30 months (range, 17.1 to 51.5) for the entire group, the 2-year progression-free survival rate was 64% (90% CI, 50% to 75%) and the 2-year overall survival rate was 69% (90% CI, 43% to 85%). For the 29 patients who underwent tandem SCT, the 2-year progression-free survival rate was 72% (90% CI, 55% to 83%) and the 2-year OS rate was 89% (90% CI, 74% to 96%). Tandem AutoSCT-RIC AlloSCT appears to be safe and effective in patients with high-risk lymphoma. Prospective trials using such an approach in specific lymphoma subtypes are warranted.