Prevalence of central and lateral cervical lymph node metastasis in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. Lymph node metastasis are common in PTC. Aim of this study was to investigate prevalence of metastatic cervical lymph nodes (LN) in PTC and possible association between metastasis in central and lateral LN. Five-year data (2016-2020) from Eurocrine registry of 117 patients who underwent thyroidectomy with LN dissection for PTC were retrospectively analyzed. Patients were divided in two groups - group A one side central LN dissection (n-104) and group B one side central and lateral LN dissection (n-13). In group A central LN metastases were found in 47 (45.2%) and in group B - 9 (69.2%) cases. There was no strong statistically significant difference found between positive central LN in group A and B (p=0.058). Average count of dissected central LN in group A was 6.3 (1-30) with positive 3.2 (1-16). In group B average count of dissected central LN was 8.2 (2-18) with positive 3.7 (1-10). In group B metastatic lateral LN were found in 9 (69.2%) cases. Average count of dissected lateral LN was 10.0 (3-17) with positive 5.2 (1-9). In group B there were 3 (23%) cases with positive lateral LN but negative central LN and vice versa – 3 cases (23%) with positive central and negative lateral LN. One patient (7.7%) had both negative central and lateral LN. Tumor size in group A vs B was T1-56.7% vs 38.5%, T2-20.2% vs 23.1%, T3-18.3% vs 30.8%, T4-4.8% vs 7.7%, respectively. Although papillary thyroid carcinoma has good overall prognosis, possibility of metastases in cervical lymph nodes must be considered during preparation of every PTC surgery. Larger tumors were associated with higher risk of metastasis in lateral LN.