Association of the Preoperative Controlling Nutritional Status (CONUT) Score with Clinicopathological Characteristics in Patients with Papillary Thyroid Carcinoma.

Background: The Controlling Nutritional Status (CONUT) score is an immunonutritional test tool based on serum albumin, total cholesterol, and lymphocyte counts. It has been studied as a simple prognostic predictor for various carcinomas. This study aimed to investigate the association between preoperative CONUT scores and the clinicopathological characteristics in papillary thyroid carcinoma (PTC) patients.

Methods: This study included 2,403 PTC patients who underwent total thyroidectomy between 2012 and 2016 at a single tertiary medical center. The CONUT scores were calculated based on preoperative blood tests. The clinicopathological characteristics were retrospectively reviewed. The patients were categorized by the CONUT score (relatively low, 0-2; relatively high, 3-5).

Results: Among the 2,997 PTC patients who underwent total thyroidectomy at Pusan National University Hospital between 2012 and 2016, those without preoperative blood test were excluded (n=149). Finally 2,403 patients were analyzed after excluding 439 patients taking lipid-lowering drugs and six patients without available T stage data after surgery. Based on the CONUT score, the relatively high score group had a lower body mass index (23.7±3.3 kg/m2 vs. 21.9±2.9 kg/m2, P<0.001), more advanced T stage (T stage 3/4, 5.9% vs. 11.4%, P=0.045), and higher extrathyroidal extension (2.1% vs. 7.6%, P=0.005).

Conclusion: Patients included in this large, single-center study all had a preoperative CONUT score of 0-5, but this study demonstrated that higher preoperative CONUT scores were significantly associated with advanced T stage and extrathyroidal extension. The CONUT score, which can be easily used in clinical practice, is thought to be helpful in predicting the aggressiveness of PTC.