Survival outcomes and failure patterns in stage I/II extranodal NK/T-cell lymphoma after involved site radiotherapy with asparaginase-based chemotherapy-a retrospective study

We aimed to analyze survival outcomes and failure patterns in stage I/II extranodal NK/T-cell lymphoma (ENKTCL) treated with involved site radiotherapy (ISRT) combined with asparaginase-containing chemotherapy regimens. Kaplan-Meier method was performed to calculate overall survival (OS) and progression-free survival (PFS). Univariate and multivariate Cox proportional hazards models were employed to identify independent prognostic factors for OS and PFS. The 2-year, 5-year OS and 2-year, 5-year PFS were 90.6%, 87.5% and 88.3%, 82.2%, respectively. Univariate and multivariate analyses identified primary tumor location, Lugano stage, and radiotherapy doses as prognostic factors for PFS. A total of 27 patients developed recurrence, 3 patients (1.8%) developed in-field recurrence, 3(1.8%) patients developed concurrent in-field and out-of-field recurrence and 21 (12.3%) patients developed out-of-field recurrence. The 5-year local recurrence-free rate of 96.5%. Patients with stage I/II ENKTCL treated with ISRT combined with asparaginase-containing chemotherapy regimens exhibit favorable prognoses.