Autologous stem cell transplantation in Mantle Cell Lymphoma: Survival and the role of cytarabine in conditioning regimens

Introduction: Mantle cell lymphoma (MCL) is a rare and heterogeneous lymphoproliferative neoplasm characterized by frequent relapses and poor long-term survival. Autologous hematopoietic cell transplantation (auto-HCT) has been used as a consolidation strategy in first remission, especially in younger patients. International studies suggest that the use of cytarabine in treatment can significantly improve clinical outcomes. Objective: To evaluate the impact of the main factors on the survival of auto-HCT in patients with MCL, including the use of cytarabine in chemotherapy conditioning. Methods: Longitudinal, retrospective, multicenter study with data obtained from medical records of patients diagnosed with MCL and undergoing autologous HSCT between 2004 and 2024. Patients from 2 centers in Minas Gerais and the Brazilian Registry of Mantle Cell Lymphoma were included. The variables were analyzed using descriptive statistics, Kaplan-Meier and Cox regression. Results: Forty patients with mantle cell lymphoma undergoing autologous hematopoietic stem cell transplantation, aged between 40 and 70 years, 85% of whom were male, were included in the study. The majority (90%) had advanced clinical staging (III/IV) at diagnosis, evidencing the aggressiveness and late presentation pattern of the disease. The 3-year overall survival (OS) was 63.5% and the progression-free survival (PFS) was 59%. No statistically significant associations were observed with sex, age, staging and MIPI score. However, in the 3-year survival analysis, the use of cytarabine in the conditioning regimen demonstrated a positive impact on OS (64% vs. 27%; p<0.01) and PFS (75.3% vs. 27%; p<0.01). Multivariate Cox regression analysis reinforced this finding, with the use of cytarabine in conditioning being identified as an independent protective factor for mortality, reducing the risk of death by 89% (HR=0.11; 95% CI: 0.017–0.71; p=0.021). Conclusion: The use of cytarabine in the conditioning regimen was associated with better OS and PFS in this study, indicating its benefit also in the conditioning regimen for auto-HCT in patients with MCL. The findings reinforce the importance of its use in conditioning protocols for auto-HCT, corroborating what is already known about its benefits in induction chemotherapy for patients with MCL.