: Controlling Nutritional Status CONUT is an efficient tool for early detection of malnutrition, measured using two biochemical parameters serum albumin and total cholesterol and one immune indicator total lymphocyte count . The aim of this study was to de ne the ef cacy of CONUT for predicting postoperative complications in very elderly patients with colorectal cancer. This study enrolled 52 patients aged 85 years or older with colorectal cancer for whom we were able to measure CONUT before surgery, conducted at the Department of Gastroenterological and General Surgery of Showa University Hospital in Japan between January 2010 and December 2014. The patients were subdivided into those with complications Group C, n 9 and those with no complications Group NC, n 43 , and then were retrospectively compared for clinical characteristics, CONUT, and surgical outcomes. Multivariate analysis was nally performed to identify the risk factors of complications.The percentage of patients with a CONUT score of 5 or more in Group C was significantly greater than that in Group NC 7 vs. 12 patients, 77.8 vs. 27.9 , P 0.0079 . No other signi cant difference was observed in the clinical characteristics between Group C and Group NC. Multivariate analysis identi ed CONUT score as the only signi cant predictor of complications in this patient cohort odds ratio 1.374 ; 95 con dence interval, 1.019-1.949 ; P 0.0366 . Our study suggests that CONUT score is predictive of postoperative complications in very elderly patients with colorectal cancer.