A Novel Nomogram Integrated with Preablation Stimulated Thyroglobulin and Thyroglobulin/Thyroid-Stimulating Hormone Ratio to Predict the Therapeutic Response of Intermediate‑ and High‑Risk Differentiated Thyroid Cancer Patients: a Bi-center Retrospective Study

Abstract Purpose To investigate the factors influencing the outcome of radioactive iodine (RAI) treatment in intermediate- to high-risk patients with differentiated thyroid carcinoma (DTC). Methods We enrolled 553 DTC patients who underwent total thyroidectomy and categorized them into two groups according to their response to RAI therapy: excellent response (ER) and non-ER groups. Clinical and pathological characteristics of the patients were collected and retrospectively analyzed using univariate and multivariate binary logistic regression. Receiver operating characteristic (ROC) curves and diagnostic cutoff values were analyzed to assess the predictive value of important quantitative influences on 131I treatment outcomes. A new nomogram model was developed based on the above independent risk factors. R software was used to develop nomograms with all the independent prognostic factors included. Results The multivariate analysis showed that lymph node metastasis (LNM), stimulated thyroglobulin (sTg), thyroglobulin antibodies (TgAb), and sTg/thyroid-stimulating hormone (TSH) were significantly associated with non-ER of DTC patients. In the training set, the consistency index (C-index) of the new column line graph was 0.868 (95% CI 0.865–0.871), which was significantly higher than the C-index of the conventional 8th edition AJCC TNM staging. Conclusion We proposed a new nomogram to predict non-ER for DTC with excellent discrimination and calibration.