Preoperative Prediction of Lymph Node Metastasis in T1N0M0 Papillary Thyroid Carcinoma by Using Contrast-enhanced Ultrasound

Similarly, the burden of central lymph node metastasis affects the individualized management of patients with T1N0M0 papillary thyroid carcinoma (PTC): lymph node metastasis is a contraindication to thermal ablation; low-burden lymph node metastasis is suitable for lobectomy; and high-burden lymph node metastasis recommends total thyroidectomy. However, conventional preoperative imaging examinations have low efficacy in diagnosing central lymph node metastasis. This multicenter retrospective cross-sectional study enrolled 600 patients with T1N0M0 PTC who were admitted to our hospital from June 2018 to June 2025 and confirmed by postoperative pathology. Dynamic contrast-enhanced ultrasound (CEUS) images of the thyroid and lymph nodes before surgery were collected for all patients. Two senior ultrasound physicians unaware of the pathological results independently analyzed the images and extracted qualitative and quantitative CEUS features of lesions and suspicious lymph nodes. Taking postoperative pathological results as the gold standard, patients were divided into the high-burden metastasis group, low-burden metastasis group, and non-metastasis group. Univariate and multivariate Logistic regression analyses were used to screen independent predictors, construct a combined predictive model, and draw receiver operating characteristic (ROC) curves and decision curves to evaluate its diagnostic efficacy and clinical practicality. The primary outcome measure was the area under the curve (AUC), and the secondary outcome measures included sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and net benefit. This project is expected to achieve accurate preoperative prediction of the burden of central lymph node metastasis and realize precise and individualized treatment for patients with T1N0M0 PTC.