Controlling Nutritional Status (CONUT) score is a prognostic marker in III-IV NSCLC patients receiving first-line chemotherapy

Background To investigate the prognostic impact of the controlling nutritional status (CONUT) score in non-small-cell lung cancer (NSCLC) patients receiving first-line chemotherapy. Methods We retrospectively reviewed 278 consecutive patients undergoing chemotherapy for stage III-IV NSCLC between May 2012 and July 2020. CONUT score was calculated by incorporating serum albumin, total cholesterol, and total lymphocyte count. The patients were divided into two groups: CONUT ≥ 3 and CONUT < 3, according to receiver operating characteristic (ROC) analysis. The associations of CONUT with clinicopathological factors and survival were evaluated. Results A high CONUT score was significantly associated with older age( P = 0.003), worse ECOG-PS( P = 0.018), advanced clinical stage( P = 0.006), higher systematic inflammation index (SII) ( P < 0.001)and lower prognostic nutritional index (PNI) ( P < 0.001).The high CONUT group had a significantly shorter progression-free survival(PFS) and overall survival(OS) than the low CONUT group. In the univariate analysis, higher SII, higher CONUT, advanced clinical stage and lower PNI were associated with worse PFS ( P all < 0.05). Worse ECOG-PS, higher SII, higher CONUT, advanced clinical stage and lower PNI were associated with worse OS ( P all < 0.05). In multivariate analysis, CONUT(HR, 2.487; 95%CI 1.818 ~ 3.403; P < 0.001) was independently associated with PFS, while PNI(HR, 0.676; 95%CI 0.494 ~ 0.927; P = 0.015) and CONUT(HR, 2.186; 95%CI 1.591 ~ 3.002; P < 0.001)were independently associated with OS. In ROC analysis, CONUT had a higher area under the ROC curve (AUC) for the prediction of 24-month PFS and OS than the SII or PNI. When the time-dependent AUC curve was used to predict PFS and OS, CONUT tended to maintain its predictive accuracy for long-term prognosis at a significantly higher level for an extended period after chemotherapy when compared with the other markers tested. The CONUT score showed better accuracy of predicting OS (C-index: 0.711) and PFS(C-index: 0.753). Conclusion CONUT score is an independent prognostic indicator of poor outcomes for patients with stage III-IV NSCLC and is superior to the SII and PNI in terms of prognostic ability.