Sonographic features of papillary thyroid microcarcinoma predicting high-volume central neck lymph node metastasis.

OBJECTIVE: To study the correlations between the sonographic features of papillary thyroid microcarcinoma (PTMC) and the presence of high-volume lymph node metastasis.

METHOD: Medical records of 2363 PTMC patients were reviewed form October 2013 to December 2015. All the patients with lymph node metastasis identified by histopathology were included. Preoperative sonographic features, such as multifocality, tumour size, echogenicity, calcification, vascularity of papillary microcarcinoma, and capsule invasion, were recorded. Univariate and multivariate analyses were performed to investigate the relationships between sonographic features and high-volume lymph node metastasis (number of metastatic lymph nodes >5).

RESULTS: In total, 152 patients had high-volume central lymph node metastasis (6.4%, 152/2363). Multiple logistic regression analysis showed that the preoperative ultrasonic features of microcalcifications (OR = 3.33, p = 0.022), larger tumour size (>7 mm) (OR = 2.802, p < 0.001), and capsule invasion (OR = 2.141, p = 0.006) were independent risk factors for high-volume lymph node metastasis in the central compartment of PTMC.

CONCLUSION: The sonographic features of primary papillary microcarcinoma of the thyroid are correlated with high-volume central lymph node metastasis.