Diagnostic Performance of the CUT Score in Assessing the Malignancy Risk of Thyroid Nodules

Various scoring systems in order to predict the malignancy risk in thyroid nodules (TNs) have been developed. CUT is one of the novel scoring systems. In this study, we aimed to evaluate its performance in predicting the malignancy risk in TNs and validity in the presence of Hashimoto's thyroiditis (HT). We retrospectively evaluated a total of 252 TNs with a fine needle aspiration biopsy. The CUT scores (Clinical, Ultrasonographic, and Thyroid Cytological scoring system) of the nodules were compared with ATA, ACR-TIRADS and KWAK-TIRADS scores and the histopathology of the nodules. Patients with HT were also compared with m-TIRADS classification. The CUT scores of nodules with malignant histopathology were significantly higher than the benign nodules (3.59 vs. 4.63, p< 0.001). The area values under the ROC curve of ACR-TIRADS, KWAK-TIRADS, ATA and CUT scoring systems were similar and significantly higher than the reference line [ACR-TIRADS, AUC was 0.762 (95% CI: 0.702-0.822, p< 0.001); KWAK-TIRADS, AUC was 0.759 (95% CI: 0.699-0.819, p< 0.001); CUT score, AUC was 0.759 (95% CI: 0.700-0.819, p< 0.001); ATA, AUC was 0.748 (95% CI: 0.687-0.810, p< 0.001)]. The areas under the ROC curve were similar when the efficiency of the CUT score was compared with m-TIRADS [CUT score, AUC was 0.772 (95% CI: 0.669-0.876, p< 0.001); m-TIRADS, AUC was 0.770 (95% CI: 0.667-0.874; p< 0.001)] in patients with HT. Our study showed that CUT scoring system was as effective as other scoring systems in predicting the risk of malignancy in thyroid nodules. Furthermore, CUT score is also effective in the presence of HT.