Lateral Lymph Node Metastasis Prediction in Papillary Thyroid Cancer Patients with Suspicious Preoperative Imaging Findings

Abstract

Purpose: Lateral lymph node metastasis of papillary thyroid cancer (PTC) is indicative of tumor aggressiveness and can determine treatment strategies. However, the role of prophylactic lateral lymph node dissection in the management of PTC is unclear. This study evaluated factors predictive of lateral lymph node metastasis in patients with suspicious lymph node enlargement in preoperative imaging.Methods: This retrospective study included 728 patients with newly diagnosed PTC who underwent therapeutic surgery. Clinicopathologic results were reviewed, and factors predictive of lateral lymph node metastasis were analyzed.Results: Of the 242 patients with lymph node metastasis, 50 had lateral lymph node metastasis. Lateral lymph node metastasis was associated with sex, tumor size, preoperative thyroid stimulating hormone (TSH) concentration and presence of central lymph node metastasis. Among patients with suspicious lateral lymph node metastasis by ultrasono-graphy, high TSH level (odds ratio 3.833, P=0.031) and number of metastatic central lymph nodes (odds ratio 3.68, P=0.025) were significantly predictive of lateral lymph node metastasis.Conclusion: High serum TSH level and central lymph node metastasis were predictive of lateral lymph node metastasis in PTC patients with suspicious preoperative imaging findings. These predictive factors might help reduce unnecessary therapeutic lateral lymph node dissection.