Improved Overall Survival Associated With Decreased Distant Metastasis Following Asparaginase-Based Chemotherapy and Radiotherapy for Intermediate- and High-Risk Early-Stage Extranodal Nasal-Type NK/T-Cell Lymphoma.

Purpose/Objective(s) This study evaluated the survival benefit of asparaginase (ASP)-based versus non-ASP-based regimens in a real-world cohort of patients with early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL). Materials/Methods In the modern era, we identified 376 patients who received combined radiotherapy with either ASP-based (asparaginase, platinum and gemcitabine, n = 286) or non-ASP-based (platinum and gemcitabine, n = 90) regimens. The patients were stratified into low-, intermediate- and high-risk groups using the early stage-adjusted nomogram-revised risk index (ES-NRI). Overall survival (OS) and distant metastasis (DM)-free survival (DMFS) between the chemotherapy regimens were compared using inverse probability of treatment weighting (IPTW) and multivariable analyses. Results ASP-based (versus non-ASP-based) regimens significantly improved 5-year OS (84.5% vs. 73.2%, P = 0.021) and DMFS (84.4% vs. 74.5%, P = 0.014) for intermediate- and high-risk patients, but not for low-risk patients. Moreover, ASP-based regimens decreased DM, with 5-year cumulative DM rate of 14.9% for ASP-based regimens compared with 25.1% (P = 0.014) for non-ASP-based regimens. The survival benefit of ASP-based regimens remained consistent after adjusting the confounding variables by IPTW and multivariate analyses. Additional sensitivity analyses confirmed these results. Conclusion These findings provide an evidence supporting ASP-based regimens as a first-line combined-modality treatment for intermediate- and high-risk early-stage ENKTCL.