Jun Shao,1 Xiya Wang,1 Haiyuan Yu,1 Wei Ding,1 Bin Xu,1 Dongsheng Ma,1 Xuechun Huang,2 Hongqing Yin1 

1Department of Medical Ultrasound, Affiliated Kunshan Hospital of Jiangsu University, Kunshan, 215300, People’s Republic of China; 2Department of Medical Ultrasound, Affiliated Changzhou No. 2 People’s Hospital of Nanjing Medical University, Changzhou, 213000, People’s Republic of China

Correspondence: Xuechun Huang; Hongqing Yin, Email ylgc20162022@163.com; sjwwy163@163.com

Background: The advantages of the dissecting the metastatic lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) remain a great deal of controversies in papillary thyroid carcinoma (PTC) patients without clinical evidence. The purpose of our retrospective research was to investigate the predictive factors of the LN-prRLN in cN0 PTC patients.
Methods and Materials: Altogether 251 consecutive cN0 PTC participants accepted unilateral or bilateral thyroidectomy accompanied with LN-prRLN dissection between June 2020 and May 2023 were included in the research. Then, univariate and multivariate logical regression analysis were conducted to analyze the relationship between the LN-prRLN and these predictive factors, and a predictive model was also developed. Surgical complications of LN-prRLN dissection were also presented.
Results: The rate of LN-prRLN was 17.9% (45/251) in cN0 PTC patients after the analysis of postoperative histology. The age < 55 years, multifocality, microcalcification, and BRAFV600E mutation were identified to be predictive factors of LN-prRLN in cN0 PTC patients. The risk score for LN-prRLN was calculated: risk score = 1.192 × (if age < 55 years) + 0.808 × (if multifocality) + 1.196 × (if microcalcification in nodule) + 0.918 × (if BRAFV600E mutation in nodule). The rates of the transient hypoparathyroidism and hoarseness were 1.2% (3/251) and 2.0% (5/251), respectively.
Conclusion: The age < 55 years, multifocality, microcalcification, and BRAFV600E mutation are independent predictors of the LN-prRLN in cN0 PTC patients. An effective predictive model was established for predicting the LN-prRLN in cN0 PTC patients, with the aim to better guide the surgical treatment of PTC. A thorough inspection of the lateral compartment is recommended in PTC patients with risk factors. The multicenter research with long-term follow-up should be carried out to ascertain the optimal surgical approach for patients with PTC.

Keywords: papillary thyroid carcinoma, ultrasound, BRAFV600E mutation, lymph nodes posterior to the right recurrent laryngeal nerve, predictive model