Abstract:

A study on the correlation between the age of diagnosis and the neck central lymph node metastases in papillary thyroid microcarcinomas                  LI Xiao-jing，YANG Le，MA Bin-lin. Department of Breast, Head and Neck Surgery, the Affiliated Tumor Hospital of Xinjiang Medical University,Urumqi 830011,China
Corresponding author: MA Bin-lin,E-mail:mbldoctor@126.com
Abstract    Objective    To determine the pathologic characteristics and predictive factors that increased the neck cental lymph node metastasis（CLNM）in papillary thyroid microcarcinoma（PTMC）. Especially，to determine the correlations between age and the neck central lymph node metastases at different age cutoffs ，and the real relation between age and the central lymph node metastases in papillary thyroid microcarcinomas. Methods    The clinical and pathologic data collected from 1988 patients who were firstly diagnosed with PTMC at the Affiliated Tumor Hospital of Xinjiang Medical University between January 2010 and March 2016 were analyzed retrospectively. Chi-square test ，the curve of receiver operating characteristic（ROC） and multivariate Logistic regression analysis were used to identify the risk factors of the neck central lymph node metastasis. Age at diagnosis was cut from 25 to 70 years at 5-years intervals and was cut from 30 to 60 years at 1-years intervals again, in order to determine the correlations between age and the central lymph node metastases in papillary thyroid microcarcinomas. Results    Of all 1988 patients，34.9% had the neck central lymph node metastasis，and the rate of the neck central lymph node metastasis declined with the age increasing. However，in papillary thyroid microcarcinomas，except for age cutoff of 70 years，age was independently correlated with the neck cental lymph node metastasis at different age cutoffs which was from 25 to 70 years at 5-years intervals or from 30 to 60 years at 1-years intervals. Multivariate logistic regression analysis indicated that male， the number of focality ≥3， tumor diameter ＞5 mm， unifocal tumor location in the lower third of the thyroid lobe ，capsular invasion were independently correlated with the neck central lymph node metastasis（P<0.05）. Conclusion    Age at diagnosis，not being a cutoff， only reflects variation tendency. And regarding age as continuous variable is more superiority in the study between age and the central lymph node metastases in papillary thyroid microcarcinom. Then， more aggressive treatment or more frequent follow-up could be considered for patients with unfavorable features （male， the number of focality ≥3， tumor diameter ＞5 mm，capsular invasion，unifocal tumor location in the lower third of the thyroid lobe）， as the patients may be at an increased risk for the neck cental lymph node metastasis.

Key words: papillary thyroid microcarcinoma, the neck cental lymph node metastasis, risk factors, age at diagnosis

摘要：

目的    探讨甲状腺微小乳头状癌（PTMC）临床病理学特征及中央区淋巴结转移（CLNM）危险因素；尤其探讨不同年龄截点下，确诊年龄与CLNM相关性，阐述确诊年龄实际意义。方法    回顾性分析新疆医科大学附属肿瘤医院2010年1月至2016年3月初治的1988例PTMC病人临床病理学特征，通过χ2检验、ROC曲线及多因素统计分析，探讨CLNM危险因素。又将25～70岁年龄区间中每5岁及30～60岁年龄区间中每岁为年龄截点，分别探讨不同年龄截点下，确诊年龄与PTMC中央区淋巴结转移相关性。结果    CLNM发生率为34.9%，且其随确诊年龄增加而明显下降。除70岁截点外，25～70岁年龄区间中每5岁及30～60岁年龄区间中每岁为截点差异均有统计学意义（P＜0.05），即上述确诊年龄截点均可提示确诊年龄是CLNM独立危险因素。多因素分析显示，男性、肿瘤数目≥3枚、肿瘤直径＞5 mm、单灶位于下极、包膜浸润是影响CLNM发生的独立危险因素（P＜0.05）。结论    确诊年龄是PTMC中央区淋巴结转移独立危险因素，但其仅反映CLNM风险变化趋势，无确定截点；将年龄看成连续型变量，在相关研究结果阐述中更加合理。其次，当PTMC存在以下情况，如男性、肿瘤数目≥3枚、肿瘤直径＞5 mm、单灶位于下极、包膜浸润，应警惕CLNM可能。

关键词: 甲状腺微小乳头状癌, 中央区淋巴结转移, 危险因素, 确诊年龄