Suspicious ultrasound characteristics correlate with multiple factors that predict central lymph node metastasis of papillary thyroid carcinoma: Significant role of HBME-1

Purpose: Papillary thyroid carcinoma (PTC) is frequently associated with central lymph node metastasis (CLNM). In the present study, we aimed to identify possible risk factors for CLNM in PTC, including suspicious ultrasound (US) features coexisting with thyroid diseases, immunohistochemical markers, and BRAF(V600E). These were used to establish a model to predict the risk of CLNM. Methods: From January 2016 to March 2018, we identified a cohort of patients with classic PTC who underwent cervical US and were diagnosed by postoperative pathology. Fine-needle aspiration biopsies were analyzed for the presence of BRAF(V600E), and immunohistochemistry was used to detect tumor markers. US imaging was performed in accordance with a standardized protocol. A model to determine the risk of CLNM was established using the outcomes of univariate and multivariate analyses. Results: Age of >= 45 years, male sex, mean tumor diameter of 1.0 cm, taller-than-wide tumor shape, multiple PTCs, capsule contact, and HBME-1 expression were significant independent risk predictors of CLNM. Hashimoto's thyroiditis, nodular goiter, and BRAF(v600E) were not significantly associated with CLNM. The cutoff value (area under the curve = 0.760) for predicting risk was determined from receiver operating characteristic curves (sensitivity, 75.6 %; specificity, 60.7 %). Conclusions: Male sex, age of >= 45 years, mean tumor diameter of >= 1.0 cm, taller-than-wide shape, multiple tumors, capsule contact, and HBME-1 expression were independent predictors of the risk of CLNM in patients with PTC. The risk model may be useful for evaluating patients' prognoses and selecting optimal surgical strategies.