Clinical features of lymph node metastasis in papillary thyroid microcarcinoma with (131)I treatment

Abstract

Objective To analyze the clinical features of lymph node metastasis in papillary thyroid microcarcinoma(PTMC). Methods 198 patients with PTMC who have underwent total thyroidectomy and at least one 131I treatment were divided into two groups according to the occurrence of lymph node metastasis. The clinical features of lymph node metastasis in PTMC were retrospective analyzed, and independent risk factors of the central and lateral lymph node metastasis in PTMC patients were further analyzed. Results Clinical features of PTMC patients with cervical lymph node metastasis: (1)Most of them were<45 years old(63.4% vs 44.9%, P=0.012); (2)More patients with cancer in bilateral lobes and extrathyroidal extension in lymph node metastasis groups(56.7% vs 42.0%, P=0.043; 63.6% vs 36.4%, P=0.034); (3)The average tumor size of the patients of lymph node metastasis was larger than that of the patients without lymph node metastasis[(0.71±0.25 vs 0.64±0.24)cm, P=0.047]; (4)Preoperative thyroglobulin antibody(TgAb)level of PTMC patients with cervical lymph node metastasis was higher than the control group[(65.27±139.179 vs 36.36±95.647)IU/L, P=0.03]; (5)After the 131I treatments and by 1-6 years of follow-up, it is found no statistically significant difference in cure rate between patients with cervical lymph node metastasis after total thyroidectomy and its control group. But the frequency of 131I treatment required in patients with cervical lymph node metastasis was higher than that of the control group(1.77±0.77 vs 1.49±0.74, P=0.006). Univariate analysis revealed that central lymph node metastasis was correlated with age, tumor size and other factors. There were more patients with cancer in bilateral lobes and extrathyroidal extension in lymph node metastasis group. And lateral lymph node metastasis was correlated with Hashimoto′s thyroiditis. Multivariate analysis showed that age, tumor size, involvement of bilateral glandular lobes and extrathyroidal extension were independent risk factors for central lymph node metastasis. Conclusion The risk factors of lymph node metastasis should be fully evaluated to carry out individualized treatment for the first operation of PTMC patients. (Chin J Endocrinol Metab, 2016, 32: 900-905) Key words: Papillary thyroid microcarcinoma; Lymph node metastasis; Clinical feature; Risk factors