Laterocervical Lymph Node Metastases in Papillary Thyroid Carcinoma: Predictive Factors for Recurrence and Oncological Outcome

<b>Background/Objectives</b>: Papillary cancer is the most common thyroid cancer. The development of lateral cervical lymph node metastases (I-V levels) is considered a major cause of recurrence. The aim of this study is to investigate the potential predictive factors for lateral cervical lymph node metastasis and disease recurrence, in order to tailor the clinical approach to these patients. An ROC (Receiver Operating Characteristic) curve has been set to search out a cut-off value for the lymph node ratio (LNR), a ratio of involved lymph nodes-to-examined lymph nodes, that could serve as an index of tumor recurrence. <b>Methods</b>: This was an observational retrospective study. The clinical charts of 43 patients with histopathological diagnosis of papillary thyroid cancer who underwent thyroidectomy with lateral and central neck dissection have been reviewed. These results have also been compared with those who underwent total thyroidectomy alone that served as a control group. <b>Results</b>: Extrathyroidal extension (<i>p</i>-value < 0.001), tumor size (<i>p</i>-value = 0.015), number of lymph nodes involvement (<i>p</i>-value = 0.022), and LNR (<i>p</i>-value = 0.004) were identified as potential predictors of tumor recurrence. The ROC curve revealed that an LNR value exceeding 0.205 is indicative of disease recurrence, with an Area Under the Curve (AUC) of 0.818, a sensitivity of 82%, and a specificity of 81%. Furthermore, fT4 value (<i>p</i>-value = 0.008), tumor size (<i>p</i>-value = 0.019), and alcohol consumption (<i>p</i>-value < 0.001) may serve as potential predictors of lymph node metastasis. <b>Conclusions</b>: Extrathyroidal extension, vascular invasion, tumor size, number of pathological lymph nodes, and LNR are associated with recurrence of papillary thyroid carcinoma; in particular, the lymph node ratio can be considered an effective indicator of recurrence risk.