Establishment of risk score for papillary thyroid carcinoma and comparison of diagnostic efficacy with thyroid fine needle aspiration cytodiagnosis

Abstract

To develop a simple and easy promotion risk score to identify individuals with undiagnosed papillary thyroid carcinoma (PTC), and further to compare the diagnostic efficiency of PTC risk sore with fine needle aspiration cytodiagnosis (FNAC). in order to optimize the screening process of PTC. A sample of 1 003 individuals aged 11-82 years underwent a surgical treatment of thyroid nodule participated in the study. The risk score was developed by stepwise backward multiple logistic regression. And using the receiver operating characteristic (ROC) curve to evaluate the diagnostic efficacy, the best diagnostic cut-off point and the risk stratification of malignant. Compare the sensitivity, specificity, accuracy, and area under curve (AUC) of PTC risk score, FNAC and their combined diagnosis to judge their diagnostic efficiency. The risk score included age, TSH, nodule morphology and boundary by palpation, nodule characteristics, shape, boundary, calcification and blood flow signal by ultrasound. Its AUC=0.815, 6 point was the best cutoff point to differentiate benign from malignant thyroid nodules, and risk stratification of thyroid carcinoma were divided into four levels: very high risk group (score ≥ 9 points), high risk group (score were 5-8 points), moderate risk group (score were 3~4 points), low risk group (score ≤ 2 points). The sensitivity, specificity, and accuracy of FNAC were 86.3%, 90.0%, and 87.0% respectively, AUC=0.891, while the sensitivity, specificity, and accuracy of PTC risk rating scale were 83.8%, 70.0%, and 81.0% respectively, AUC=0.822. The sensitivity, specificity, and accuracy of their combined diagnosis were 97.5%, 85.0%, and 95.0%, AUC=0.965. This risk score can be used as a screening method before FNAC. If combined with FNAC, it may improve the diagnostic efficacy of PTC, and thereby possibly minimizing the unnecessary invasive examination and surgical treatment for patients with thyroid nodules and reducing personal costs. (Chin J Endocrinol Metab, 2017, 33: 755-759) Key words: Thyroid papillary carcinoma; Scale; Risk score; Logistic regression analysis; Fine needle aspiration cytology; Diagnostic test