1086 - PD-1/PD-L1 Blockade Added to First-Line Asparaginase-Based Chemotherapy with or without Radiotherapy in Extranodal Nasal-Type NK/T-Cell Lymphoma: A Multicenter Retrospective Study from the CLCG

05:15pm - 05:20pm ET

Room 162

Presenter(s)

Yue Liu, MD - National Cancer Center CAMS & PUMC, Beijing, Beijing

Y. Liu, X. Liu, S. Qi, and Y. LI; Department of Radiation Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China

Purpose/Objective(s): The present study investigated the survival impact of adding PD-1/PD-L1 blockade to first-line contemporary therapy in a large, real-world cohort of patients with extranodal natural killer/T-cell lymphoma (ENKTCL).

Materials/Methods: Using the China Lymphoma Collaborative Group (CLCG) database (2015-2025), we identified 1478 newly diagnosed ENKTCL patients who received first-line asparaginase (ASP)-based chemotherapy with or without radiotherapy. Patients who additionally received PD-1/PD-L1 blockade were classified as the immunotherapy (IO) group, while the remaining patients comprised the non-IO group. Inverse Probability of Treatment Weighting (IPTW) and multivariable analyses were used to compare overall survival (OS) and progression-free survival (PFS) between groups.

Results: Among the 1478 patients included, 472 received PD-1/PD-L1 blockade and 1,006 did not. In the unadjusted cohort, the IO-group achieved significantly improved 5-year OS compared with the non-IO group (83.5% versus 73.7%, P < 0.001), whereas 5-year PFS was comparable between groups (71.6% versus 69.5%, P = 0.227). After IPTW adjustment, the OS benefit remained significant (79.0% versus 73.1%, P < 0.001). The survival advantage associated with PD-1/PD-L1 blockade was consistent across stage and risk-stratified subgroups. The incidence of grade 3–4 adverse events did not significantly increase in the IO group.

Conclusion: The addition of PD-1/PD-L1 blockade to first-line ASP-based therapy was associated with improved overall survival without increased severe toxicity in patients with ENKTCL.