Key Ultrasonographic Features, Fine-Needle Aspiration, and Nodule Location in the Preoperative Differentiation of Benign and Malignant Thyroid Nodules: A Retrospective Study

Background This study aimed to explore clinical and ultrasonographic factors associated with malignant thyroid nodules and to develop a diagnostic prediction model integrating key ultrasound features, fine-needle aspiration (FNA), and nodule location for preoperative risk stratification. Methods We retrospectively analyzed 186 patients with thyroid nodules confirmed by surgery and pathology. Clinical data, ultrasound features, and FNA results were compared between benign and malignant groups. Variables with statistical significance in univariate analysis were entered into binary logistic regression to identify independent predictors. A combined diagnostic model was constructed and validated using receiver operating characteristic (ROC) curves. Results Among the 186 patients, 53 (28.5%) had benign and 133 (71.5%) malignant nodules. Solid composition, aspect ratio ≥ 1, calcification, and upper-pole location were independent risk factors for malignancy (P < 0.05). The combined model integrating key ultrasound features, FNA, and nodule location achieved an AUC of 0.867 with 87.2% sensitivity and 77.4% specificity, significantly outperforming any single method. Conclusions The combined model markedly improves preoperative differentiation between benign and malignant thyroid nodules and may serve as a valuable tool for personalized management.