Prognostic Potential of the Preoperative Controlling Nutritional Status (CONUT) Score in Predicting Survival of Patients with Cancer: A Systematic Review

The nutritional status of a patient has prognostic potency concerning short- and long-term outcomes, including survival, in many diseases. The controlling nutritional status (CONUT) score is a method for assessing nutritional status and predicting outcomes of several diseases. This study sought to systematically identify the prognostic role of preoperative CONUT score on posttreatment overall survival (OS), recurrence-free survival (RFS), and cancer-specific survival (CSS) in patients with cancer. The PubMed, SCOPUS, and Google Scholar databases and Google were searched for all dates until December 2019. Original articles investigating the association of preoperative CONUT score with survival in cancer patients who underwent surgery were included. Duplicate and irrelevant reports were screened out and the remaining articles assessed for quality and data extracted during critical analysis. Results of multivariate analysis were used to evaluate the prognostic competence of CONUT score in predicting survival. The search method identified an initial 181 articles, of which 32 were included in the final analysis. Lower OS, CSS, and RFS rates were reported by 100%, 100%, and 87.0% of the included studies, respectively, in cancer patients with high CONUT scores. A prognostic role of the CONUT score for prediction of OS, CSS, and RFS in cancer patients was shown by 91.7%, 90.9%, and 52.6% of the studies, respectively. The receiver operating characteristic curve area under the curve (AUC) value of the CONUT score for predicting OS, CSS, and RFS was at an acceptable level (>0.5) in all studies with available AUC values (n = 19). Sixty percent (12 of 20) of the studies reported that high CONUT score was significantly related to lower BMI. The findings promote confidence that a high preoperative CONUT score is associated with poor survival rate and is an independent prognostic factor of OS and CSS in patients with various types of cancer. Evaluation of the preoperative CONUT score might help clinicians in decision-making with respect to surgical implications.