Objective  To analyze the clinical and pathological factors related to the metastasis of contralateral central lymph nodes (Cont-CLNs) in unilateral near isthmus papillary thyroid carcinoma (PTC), and to establish a prediction model of lymph node metastasis, so as to provide reference for the scope of lymph node dissection. Methods  A total of 381 unilateral PTC patients from February 2012 to June 2022 were collected in our hospital, and according to the location of the cancer, they were divided into the isthmus group (n=152) and the unilateral glandular lobe group (n=229) , and the correlation analysis was performed on whether there was Cont-CLNs metastasis. One hundred and fifty-two patients in the unilateral isthmus PTC group were further divided into metastatic and non metastatic groups based on whether Cont-CLNs metastasis occurred. Univariate analysis was used to analyze the relationship between gender, age, distribution of glandular lobe, tumor size, tumor location, pathological subtype, capsule invasion, thyroid stimulating hormone (TSH) level, combine Hashimoto’s thyroiditis (HT), ipsilateral central lymph nodes（Ipsi-CLNs) metastasis and Cont-CLNs metastasis. According to the univariate analysis results of this study and the possible high-risk factors of contralateral central lymph node metastasis of unilateral thyroid papillary carcinoma in other literatures, they were included in logistic multivariate analysis to obtain independent risk factors and establish a prediction model. Results  The incidence of Cont-CLNs metastasis in unilateral isthmus PTC patients was higher than that in nilateral glandular lobe group (24.3% vs. 14.4%, χ²=6.009, P=0.014). Univariate analysis showed that Cont-CLNs metastasis in patients with unilateral near isthmus PTC was correlated with age (P=0.02), tumor size (P＜0.01), capsule invasion (P＜0.01) and Ipsi-CLNs metastasis (P＜0.01), but not with gender, distribution of glandular lobe, tumor location, pathological subtype, TSH level and whether to merge HT (P＞0.05). Further logistic multivariate analysis suggested that capsule invasion and Ipsi-CLNs metastasis were independent risk factors for Cont-CLNs metastasis in patients with unilateral near isthmus PTC. Moreover, the above logistic multifactor prediction model is proved to be effective by the test of goodness of fit by Hosmer and Lemeshow. Conclusions  Capsule invasion and Ipsi CLNs metastasis are high risk factors for Cont-CLNS metastasis in patients with unilateral near isthmus PTC. It is suggested that such patients should be cleaned up with prophylactic Cont-CLNs while cleaning up Ipsi-CLNs.

Citation： WANG Lin, ZHAO Zhihong. Research on high risk factors of lymph node metastasis in the contralateral central region of unilateral near isthmus papillary thyroid carcinoma. CHINESE JOURNAL OF BASES AND CLINICS IN GENERAL SURGERY, 2023, 30(6): 709-714. doi: 10.7507/1007-9424.202302063 Copy