Determination of the predictive and prognostic value of the CONUT (Controlling Nutritional Status) score in the treatment process of metastatic colorectal cancer and its relationship with the clinicopathological features of the tumor

BACKGROUND Studies have shown that the prognosis of various cancers is affected by factors such as inflammation, immunocompetence and nutrition, and the correlation between nutritional status and cancer prognosis is particularly striking. We aimed to evaluate the prognostic and predictive effect of The Controlling Nutritional Status (CONUT) score, calculated using serum albumin level (indicator of protein reserves), total cholesterol concentration (calorie consumption parameter) and total peripheral lymphocyte count (indicator of immunity), in patients with newly diagnosed metastatic colorectal cancer (mCRC). METHODS The prospectively designed study included 36 patients who were diagnosed with mCRC between June 2020 and December 2021 at the Department of Medical Oncology, Dokuz Eylul University Hospital, and were assessed according to the web-based software OpenEpi CONUT score was calculated using serum albumin level, total cholesterol concentration, and total peripheral lymphocyte count. Demographic, clinicopathological, and treatment-related characteristics of the patients, as well as CONUT values before treatment and at month 3, were recorded. The data obtained were analyzed in the SPSS statistical program according to appropriate analysis methods and the p value was < 0. 05 considered statistically significant. RESULTS The median age of the study population was 67.09 (Range: 37.37-88.30 years) years and 66.7% (n= 24) of the patients were male. The median follow-up period of the patients was 13.85 months (Range: 5.8-26.87 month) and 5.6% (n = 2) of the patients died during the follow-up period. The objective response rate (ORR) (complete and partial response) was higher in the group with low CONUT score than in the groups with medium and high CONUT scores (84.1% vs 73.3% vs 40%, respectively). When progression status was evaluated, the rate of patients progressing in the group with high CONUT score was higher than in the groups with medium and low CONUT scores (20% vs 13.3% vs 6.3% respectively). Patients with exitus were included in the CONUT high group, and the survival of these patients was shorter than in the CONUT low group. The median CONUT score value of the patients before treatment was 2 (0-11), and the median CONUT score at the 3rd month was 1 (0-10). When we looked at the correlation between the CONUT scores before treatment and at month 3, we saw that there was a statistically significant correlation between the baseline score and the 3rd month score (R: 0.36, p = 0.031). CONCLUSION Immunonutrition status is one of the factors affecting cancer prognosis, and the CONUT score, which reflects this status, has been shown to have a negative effect on prognosis if it is high at the beginning of treatment, as shown in our mCRC diagnosedpopulation of a small number of patients that we planned prospectively during the COVID period. In addition, it was thought that the decrease in the CONUT score was related to the increase in albumin values, which is a biomarker of improvement in nutritional status with systemic treatment.