AbstractBackgroundThe controlling nutritional status (CONUT) score is a nutritional index that combines serum albumin, total cholesterol, and lymphocyte counts. The potential value of CONUT score for predicting clinical outcomes in patients with nasal‐type extranodal NK/T‐cell lymphoma (ENKTL) has not been explored.MethodsThis study included 374 ENKTL patients treated with asparaginase‐containing regimens from September 2012 to September 2017. Clinical characteristics, treatment efficacy, prognostic factors, and the predictive value of CONUT score were analyzed.ResultsThe complete response (CR) and overall response rate (ORR) were 54.8% and 74.6%, respectively. Patients with CONUT scores <2 had higher CR and ORR compared to patients with scores ≥2 (69.1% vs. 48.9% for CR,p= 0.001; 90.0% vs. 74.6% for ORR,p< 0.001). The 5‐year overall survival (OS) and progression‐free survival (PFS) rates were 61.9% and 57.3%, respectively. Patients with CONUT scores <2 had better survival outcomes than those with scores ≥2 (5‐year OS, 76.1% vs. 56.0%,p< 0.001; 5‐year PFS, 74.4% vs. 50.1%,p< 0.001). CONUT score ≥2 was identified as an independent poor prognostic factor for both OS and PFS. A CONUT score ≥2 was also associated with poorer survival outcomes in low‐risk ENKTL patients.ConclusionA CONUT score ≥2 is a prognostic marker for poor survival in patients with ENKTL and could be used to stratify risk in low‐risk patients.