A Novel Noninvasive Approach for Evaluating Suspicious Cervical Lymph Nodes in Papillary Thyroid Carcinoma-Superb Microvascular Imaging.

PURPOSE: To assess the diagnostic performance of superb microvascular imaging (SMI) versus color Doppler flow imaging (CDFI) and fine-needle aspiration thyroglobulin (FNA-Tg) in detecting indeterminate cervical lymph nodes (CLNs) in papillary thyroid carcinoma (PTC) patients.

METHODS

We prospectively analyzed clinical and imaging data from 74 PTC patients with indeterminate CLNs undergoing FNA biopsy and Tg measurement. Analyses included: (1) univariate comparison of benign versus malignant CLNs; (2) Spearman correlation between imaging features and pathological findings; and (3) receiver operating characteristic curve assessment of diagnostic accuracy.

RESULTS

Among 43 benign and 31 malignant CLNs, significant differences were observed in gender (p = 0.026), age (p = 0.041), FNA-Tg levels (p < 0.001), and diagnostic outcomes for CDFI (p = 0.001) and SMI (p < 0.001). FNA-Tg (r = 0.946), SMI (r = 0.707), and CDFI (r = 0.403) correlated with pathology (all p < 0.001). FNA-Tg showed superior accuracy (AUC = 0.977) versus SMI (AUC = 0.856) and CDFI (AUC = 0.704). SMI detected more vessels than CDFI in benign (2.00 vs. 1.00) and malignant nodes (3.00 vs. 2.00) (p < 0.001), with higher overall counts (2.53 ± 1.47 vs. 1.50 ± 1.13, p < 0.001).

CONCLUSION

SMI outperformed CDFI in microvascular visualization for indeterminate CLNs in PTC. Although FNA-Tg remained the most accurate diagnostic method, SMI served as a valuable noninvasive alternative, especially when FNA-Tg was contraindicated or inaccessible.