Impact of Age on Biology, Presentation and Outcomes in Marginal Zone Lymphoma: Results From a Multicenter Cohort Study

Given the paucity of age-specific data about biology, presentation, and treatment outcomes in adults with MZL, we sought to evaluate differences between younger (≤ 70 years) and older (> 70 years) patients with MZL in a large retrospective cohort treated in the contemporary era (2010 onwards). The primary objective was progression-free survival (PFS), while secondary objectives included the evaluation of overall survival (OS) and the cumulative incidence of transformation between the 2 groups. A total of 598 patients were included in the analysis and among these 32% were > 70 years of age. There were no age-based differences in the prevalence of NMZL, SMZL, and EMZL. Older patients had a higher incidence of adverse prognostic features at diagnosis such as worse performance status, advanced stage disease, and bone marrow involvement, yet were more likely to be treated with single-agent rituximab than chemoimmunotherapy. Age > 70 years was associated with inferior PFS and OS after controlling for clinically relevant risk factors and accounting for differences in first-line treatment. Receipt of rituximab monotherapy was associated with significantly inferior PFS overall, however, the type of first-line therapy did not impact OS in any group. Our data suggests that despite the development of new drugs for MZL, age remains an independent predictor of inferior outcomes. Investigation of targeted therapy combinations in the first-line setting may yield the required balance of efficacy and toxicity in older adults with MZL.