Delphian Lymph Node Metastasis Is A Novel Indicator Of Tumor Aggressiveness And Poor Prognosis In Papillary Thyroid Cancer

Background and Objectives Although the significance of Delphian lymph nodes (DLNs) in patients with papillary thyroid carcinoma (PTC) has been reported, all studies have been based on a small sample size and lack a direct statement concerning prognosis.Methods A total of 904 consecutive patients were enrolled in the current study, and all patients were divided into two groups (DLN-positive and DLN-negative) according to the presence of DLN metastasis.Results DLN was detected in 687 patients (76.0%), and 123 (17.9%) had DLN metastasis. Compared to those in the DLN-negative group, the proportion of other central lymph node (CLN) metastases, mean number of metastatic CLNs, and mean metastatic CLN ratio were higher in the DLN-positive group (86.2 vs. 50.2%, 6.70 +/- 5.19 vs. 1.60 +/- 2.37, and 0.54 +/- 0.25 vs. 0.18 +/- 0.26, respectively; p < .001). The same phenomena were observed in the metastatic lateral lymph nodes (LLNs) between the DLN-positive and DLN-negative groups (52.0 vs. 15.4%, 7.28 +/- 6.08 vs. 3.38 +/- 3.73, and 0.23 +/- 0.15 vs. 0.13 +/- 0.12, respectively; p < .001). Patients in the DLN-positive group had shorter LLN metastasis-free survival and distant metastasis-free survival than patients in the DLN-negative group (93.5% vs. 98.6% and 95.9% vs. 98.8%, respectively, p < .05).Conclusions DLN metastasis in PTC is associated with tumor aggressiveness and a poor prognosis.