Survival after first relapse in marginal zone lymphomas: Prospective data from the international observational NF10 study.

While marginal zone lymphoma (MZL) is generally indolent, outcomes following relapse remain poorly defined. This study utilized the indolent Non Follicular 10 (NF10) prospective database to characterize survival and identify prognostic drivers in patients failing initial systemic therapy. The study analysed 122 patients with relapsed MZL. The primary end-point was progression-free survival from first relapse (2PFS), with survival after relapse (SAR) as the secondary end-point. The median 2PFS was 24 months, with a 2-year 2PFS rate of 49% and a 2-year SAR rate of 66%. Multivariable analysis identified advanced age, progression of disease within 24 months (POD24) and high MZL International Prognostic Index (MZL-IPI) scores as significant predictors of inferior survival. Patients with splenic and disseminated subtypes also demonstrated worse outcomes. Relapse following systemic therapy often marks a transition to an aggressive clinical course. Time to progression and the MZL-IPI are robust tools for risk stratification, highlighting an urgent need for novel therapeutic strategies for high-risk relapsed MZL populations.