Abstract
BACKGROUND: Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer, representing approximately 85-90% of cases. Galectin-3 (GAL-3) is a well-established histologic marker of thyroid cancer that is not expressed by normal thyroid cells. Our study aims to explore the potential utility of serum GAL-3 in differentiating PTC from benign thyroid tumors. METHODS: According to the postoperative pathology results, patients were divided into a benign thyroid tumor group (95 cases) and a PTC group (165 cases). Serum GAL-3 was detected by chemiluminescence immunoassay. Additionally, other markers, including human epidermal growth factor receptor 2 (HER2), Ki-67, cytokeratin 19 (CK19), thyroid peroxidase (TPO), and CD56, were detected by enzyme-linked immunosorbent assay (ELISA). Serum levels were compared between the two groups using SPSS 22.0. RESULTS: In patients with PTC, serum GAL-3 levels were significantly higher than those in patients with benign thyroid tumors (P=0.045). Similarly, serum HER2 and Ki-67 levels in PTC patients were also markedly higher than those in patients with benign thyroid tumors (P<0.05). However, no significant differences were found between the two groups in CK19, TPO, and CD56 (P>0.05). Multivariable analyses indicated that high GAL-3 [odds ratio (OR), 1.134; 95% confidence interval (CI): 1.046-1.228; P=0.002] and high Ki-67 (OR, 5.754; 95% CI: 2.947-11.234; P<0.001) levels were independent risk factors for PTC. The receiver operating characteristic (ROC) curve analysis revealed that GAL-3 and Ki-67 had an area under the curve (AUC) of 0.645 (sensitivity 60.9% and specificity 76.8%; P<0.001) and 0.764 (sensitivity 64.3% and specificity 81.4%; P<0.001) for distinguishing between benign thyroid tumors and PTC, respectively. When two markers were combined, the AUC increased to 0.785 (sensitivity 70.6% and specificity 87.4%; P<0.001). CONCLUSIONS: Our results suggest that the combination of serum GAL-3 and Ki-67 may serve as a useful adjunct to existing diagnostic methods of thyroid cancer, such as ultrasonography and fine-needle aspiration biopsy (FNAB).