Objective: To investigate the relationship between lymph node metastasis and the clinicopathologic features of differentiated thyroid carcinoma (DTC) patients with thyroglobulin antibody (TgAb) positive and negative.
Methods: A total of 443 patients with DTC were included in this study. Clinicopathological data of the patients were collected, including tumor size, clinical stage, calcification, Hashimoto’s thyroiditis, extra-membrane infiltration, BRAF V600E mutation status, and thyroid-related hormone and antibody levels. The relationship between of lymph node metastasis and clinicopathologic features was analyzed.
Results: There were 227(51.2%) TgAb negative and 216(48.8%) TgAb positive DTC patients. Compared with patients without lymph node metastasis, DTC patients with lymph node metastasis had a higher proportion of patients with < 55 years of age, maximum tumor diameter > 1cm, calcification, BRAF V600E mutation, and TgAb positive. Multivariate regression logistic analysis showed that < 55 years old (odds ratio (OR): 2.744, 95% CI: 1.665– 4.522, P< 0.001), maximum tumor diameter > 1cm (OR: 2.163, 95% CI: 1.431– 3.271, P< 0.001), BRAF V600E mutation (OR: 2.489, 95% CI: 1.397– 4.434, P=0.002), and TgAb positive (OR: 1.540, 95% CI: 1.020– 2.326, P=0.040) were risk factors for lymph node metastasis. Maximum tumor diameter > 1cm and BRAF V600E increased the risk by more than one fold for lymph node metastasis in TgAb-negative and TgAb-positive DTC patients.
Conclusion: Younger age (< 55 years old), maximum tumor diameter > 1cm, BRAF V600E mutation, and TgAb positive were independent risk factors for lymph node metastasis in DTC. And maximum tumor diameter > 1cm and BRAF V600E mutation were risk factors for lymph node metastasis both in TgAb positive and negative DTC patients.

Keywords: differentiated thyroid carcinoma, lymph node metastasis, thyroglobulin antibody, BRAF