Evidence of Cure for Extranodal Nasal-Type NK/T-Cell Lymphoma with Modern Treatment

Abstract

<h3>Purpose/Objective(s)</h3> Statistically, a disease is considered curable when the mortality rate of survivors returns to the same level as that of the general population. We aimed to assess the curability of extranodal nasal-type NK/T-cell lymphoma (ENKTCL) in the modern treatment era. <h3>Materials/Methods</h3> The data of 1995 patients treated between 2000 and 2016 and registered in China Lymphoma Collaborative Group (CLCG) database were analyzed. We estimated cure fractions, median survival times, and the time point of cure using a non-mixture cure model. <h3>Results</h3> The relative survival curves attained plateau for the entire cohort and most subsets, indicating that the notion of cure was robust. The overall cure fraction was 72.1%. Median survival was 1.10 years in uncured patients. The cure time was 4.5 years, i.e., beyond this time, mortality in ENKTCL patients was equivalent to that in the general population. In multivariate analysis, cure probability was associated with stage, performance status, primary tumor invasion, and lactate dehydrogenase level. Elderly patients (>60 years) had cure fraction similar to that of younger patients. Five-year overall survival rate correlated well with the cure fraction across risk-stratified groups. Thus, statistical cure is possible in ENKTCL patients receiving modern treatment strategies. <h3>Conclusion</h3> Overall probability of cure is good, though it is affected by presence of risk factors. These findings provide the rationale for treatment and follow-up of patients with different cure probabilities.