Analysis and Prediction of Regrowth in Benign Thyroid Nodules Undergoing Radiofrequency Ablation: a Retrospective Study with a 5-Year Follow-Up

To evaluate the 5-year follow-up results of radiofrequency ablation (RFA) for benign thyroid nodules (BTNs), and construct pre- and postablation nomogram models to predict regrowth in BTNs undergoing RFA. According to the occurrence of regrowth, BTNs were divided into two subgroups, the regrowth group and the nonregrowth group, and the variables were compared between these two subgroups. Then, univariate and multivariate Cox regression analyzes were utilized to filter the independent prognostic factors of regrowth, which then were introduced into the pre- and postablation prognostic nomograms, respectively. The discrimination powers and prediction performances of the nomograms were appraised by receiver operating characteristic (ROC) curves and calibration charts. The 5-year mean volume reduction rate was 88.80