Abstract: Objective The objective of this study was to analyze the risk factors affecting the curative effect of ¹³¹I treatment for non-distant metastatic papillary thyroid carcinoma(PTC),and construct a predictive model for curative effect. Methods The clinical data of 422 patients who underwent thyroid cancer resection and ¹³¹I treatment in our hospital from January 2016 to December 2020 were retrospectively analyzed.Multivariate logistic regression analysis was used to screen independent risk factors affecting the efficacy of ¹³¹I treatment,and the efficacy predictive model was constructed as well as its evaluation and validation. Results Selecting 75% patients as training set(n=319),25% patients as validation set(n=103).After multivariate logistic regression analysis in the training set,the independent risk factors of unsatisfactory ¹³¹I treatment for non-distant metastatic PTC were positive BRAF^V600E mutation,sTg/TSH≥0.05 ng/μIU,sTg/TgAb≥0.60 ng/IU,the largest diameter of lesions≥1.05 cm,the lymph node staging N1b and the lymphatic metastasis rate≥34.58%(P＜0.05).A nomogram model was constructed,and the areas under the ROC curve in the training set and validation set were 0.90(95% CI:0.87-0.94,P＜0.001)and 0.86(95% CI:0.78-0.94,P＜0.001),respectively. Conclusion The efficacy predictive model constructed in this study based on the risk factors of unsatisfactory ¹³¹I treatment efficacy in non-distant metastatic PTC has good predictive performance.

Key words: Papillary thyroid carcinoma, ¹³¹I therapy, Therapeutic effect