ObjectiveTo evaluate the predictive value of intraoperative frozen section analysis of the delphian lymph node (DLN) and pretracheal lymph node (PLN) for central lymph node metastasis (LNM) and recurrence risk stratification in patients with differentiated thyroid carcinoma (DTC). MethodsThis retrospective study included 133 DTC patients who underwent initial surgery with intraoperative frozen section evaluation of the DLN and PLN at the Department of Thyroid and Breast Surgery, Huazhong University of Science and Technology Tongji Medical College Union Hospital between January 2023 and December 2024. Receiver operating characteristic (ROC) curves were used to assess the predictive value of DLN/PLN metastasis count and ratio for central LNM and recurrence risk stratification. The concordance between intraoperative frozen pathology and final postoperative pathology was also evaluated. ResultsMultivariate analysis identified age (<20 or >50 years) as protective factor (OR=0.332, P=0.012) and capsular invasion as risk factors for DLN/PLN metastasis (OR=2.823, P=0.017). DLN/PLN metastasis number and ratio showed strong predictive performance for central LNM >5 nodes, with area under the curve (AUC) of 0.913 [95%CI (0.841, 0.986), P<0.001] and 0.910 [95%CI (0.837, 0.983), P<0.001], and optimal cut-off values of 1.5 nodes and 45.00%, respectively. For predicting intermediate-to-high recurrence risk, AUCs were 0.818 [95%CI (0.740, 0.895), P<0.001] and 0.800 [95%CI (0.720, 0.880), P<0.001], with cut-off values of 0.5 nodes and 26.79%, respectively. Intraoperative frozen pathology demonstrated a sensitivity of 88.00% (66/75), specificity of 100% (58/58), positive predictive value of 100% (66/66), and negative predictive value of 86.57% (58/67). Concordance with postoperative pathology was high, with a Kappa value of 0.849 [95%CI (0.761, 0.937), P<0.001] and the correlation coefficient of the positive rate of frozen pathology and final postoperative pathology was 0.917 [95%CI (0.885, 0.940), P<0.001]. ConclusionsIntraoperative frozen section analysis of the DLN and PLN demonstrates reliable predictive value for central LNM and recurrence risk stratification in DTC. This method may help identify patients who could benefit from an extended surgical approach and is recommended to intraoperative decision-making.
