Objective: To explore the construction of predictive model of bone metastasis in differentiated thyroid carcinoma. Methods: 1 000 differentiated thyroid carcinoma patients from January 2014 to January 2019 treated in our hospital were selected as study objectives, according to the occurrence of bone metastasis, the patients were divided into bone metastasis group(n=39) and non-bone metastasis group(n=961).The basic information of patients was compared for single factor analysis, and the significantly different single factors were analyzed by non-conditional logistic regression analysis, the dangerous factors for DTC bone metastasis and the forecast model were established to determine its predictive value. Results: There were significant differences in age, thyroid focus, number of thyroid lesions, pathological classification, neck lymph node dissection, tumor extra thyroid invasion and the time of thefirst thyroid clearance between the two groups (P<0.05). There was no significant difference in gender, mode of operation, maximum diameter of tumor, metastasis of cervical lymph nodes and TNM stage; Logistic regression analysis showed the postoperative nail clearance time (OR=6.679,95%CI 4.576-9.750), age (18-45 years) (OR=0.018,95%CI 0.001-0.507), cervical lymph node dissection (OR=3.074,95% CI 2.468-3.829), tumor extra thyroid infiltration (OR=2.140,95% CI 1.067-4.292) and multifocal carcinoma (OR=2.296,95% CI 1.136-4.640). The ROC curve showed that the AUC of postoperative nail clearance time(≥ 6 months), age (18-45 years old), cervical lymph node dissection, tumor extrathyroid invasion and multiple focal carcinoma were 0.869 (95% CI 0.831-0.907), 0.631 (95% CI 0.564-0.698), 0.801 (95% CI 0.750-0.852), 0.708 (95% CI 0.645-0.772) and 0.816 (95% CI 0.768-0.864), respectively, all of which had a certain prediction value. Conclusion: Postoperative nail clearance time, age, lymph node dissection, extrathyroid infiltration and multiple focal carcinoma are risk factors for bone metastasis of differentiated thyroid carcinoma. The model is expected to guide the prediction of bone metastasis and improve the survival rate of patients with differentiated thyroid cancer.
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