The clinical value of Delphian and pre-tracheal lymph nodes in predicting lateral lymph nodes metastasis of papillary thyroid carcinoma.

Background: Occult lymph node metastasis of papillary thyroid carcinoma is common. However, whether undergoing prophylactic lateral lymph node dissections is still controversial. This cross-sectional study with large cohort of patients aims to investigate the clinical value of Delphian and pre-tracheal lymph node in predicting lateral lymph node metastasis of papillary thyroid carcinoma.

Materials and methods: A retrospective analysis was conducted on 865 papillary thyroid carcinoma patients with Delphian and pre-tracheal lymph node data who underwent thyroidectomy plus central and lateral lymph node dissection. Data on clinicopathological characteristics were collected. Subsequently, a predictive model was established based on the results of the univariate and multivariate analyses.

Results: The rates of Delphian and pre-tracheal lymph node metastasis and lateral lymph node metastasis were 54.7% and 39.1%, respectively. Having ≥ 3 or 1-2 Delphian and pre-tracheal lymph node metastasis dramatically increased the risk of lateral lymph node metastasis (OR = 8.5, 95% CI 5.3-13.4 and OR = 3.9, 95% CI 2.7-5.7, respectively). The upper tumour had a 3.7 times higher risk of lateral lymph node metastasis than other locations. Patients ≤ 42 years or tumour size >8 mm had a higher risk of lateral lymph node metastasis.

Conclusions: Delphian and pre-tracheal lymph node metastasis was associated positively with the risk of lateral lymph node metastasis. For patients without clinical lateral lymph node metastasis, the Delphian and pre-tracheal lymph node could be considered to harvest as the first step in a thyroidectomy to facilitate further conduct of the operation.