The role of preoperative controlling nutrtional status (CONUT) score in the assessment of pathological features and survival outcomes in clear-cell renal cell carcinoma (ccRCC): A population-based study

Aim of the study: To assess the correlation between pre-operative assessment of CONUT score and pathological features, overall survival (OS) and recurrence-free survival (RFS) in patients with primary diagnosis of clear-cell renal cell carcinoma and no evidence of clinical nodal/distant metastatic disease before surgery. Materials and methods: We retrospectively review clinical data of patients treated with radical nephrectomy from 2006 to 2017. Lymph node dissection was performed for cases with intraoperative evidence of lymphadenopathy or at surgeons’ discretion for patients deemed to be at high risk for occult nodal metastases at the time of surgery. A population of 110 patients were enrolled. For each patient CONUT score was determined considering the values of pre-operative albumin, total cholesterol and lymphocyte count. ROC curve was calculated and an optimal cut-off point was set at 1. Patients were divided into 2 categories: low (≤1) and high (≥) CONUT score. Univariate and multivariate analysis were performed. RFS and OS rates were calculated and compared between the two groups. Results: High-CONUT patients were more frequently males ( p = 0.002) with pre-operative high mean fibrinogen level ( p = 0.001), longer mean hospitalization ( p = 0.012), even with no differences in Clavien- Dindo score ( p = 0.32) and more severe pathological features ( pT stage ≥3, p = 0.002; pN+, p = 0.005; venous thrombus, p = 0.036) than low- CONUT patients. No differences were observed in mean age and follow-up between the two cohorts. On multivariate analysis high- CONUT was significantly associated with worse OS (HR 10.96, 2.31– 52.15; p = 0.003), even if it didn’t result as an independent factor, comparing to age (HR 0.06, 0.02–0.29; <0.0001) and pT stage ≥3 (HR 2.63, 1.41–4.91; p = 0.002). High-CONUT wasn’t significantly asso- ciated with worse RFS (HR 1.41, 0.47–4,21; p = 0.54). Discussion: CONUT score is a low time-consuming and a good cost- effective tool, which can be easily derived from blood values that are routinely checked before surgery. In this population-based study we found that in patients diagnosed with primary ccRCC with a clinical organ-confined disease, a pre-operative high-CONUT score was a strong predictor of worse pathological stage, lymphonode status and presence of renal vein thrombosis.