游离甲状腺素与游离三碘甲状腺原氨酸比值联合促甲状腺素预测分化型甲状腺癌的临床价值

Clinical value of the free thyroxine and free triiodothyronine ration combined with thyrotropin in predicting differentiated thyroid carcinoma

目的探讨游离甲状腺素（FT4）与游离三碘甲状腺原氨酸（FT3）比值（FT4/FT3）联合促甲状腺素（TSH）预测分化型甲状腺癌（DTC）的价值。方法回顾性分析109例需手术的甲状腺结节患者的临床资料，术后病理结果显示分化型甲状腺癌61例（恶性组），良性甲状腺结节48例（良性组）。行单因素分析和多因素非条件Logistic回归分析筛选出DTC的独立危险因素，绘制受试者工作特征（ROC）曲线，计算曲线下面积（AUC），得出最佳截断值。结果恶性组和良性组性别构成和FT4比较差异无统计学意义（P〉0.05）；恶性组年龄和FT3明显低于良性组[（44.48 ± 12.07）岁比（52.81 ± 12.99）岁和（4.31 ± 0.61）pmol/L比（4.73 ± 1.05）pmol/L]，FT4/FT3和TSH明显高于良性组[3.70 ± 0.62比3.26 ± 0.70和2.15（1.42，2.78）mU/L比1.63（1.05，2.19）mU/L]，差异有统计学意义（P〈0.01或〈0.05）。多因素非条件Logistic回归分析结果显示，FT4/FT3和TSH为DTC的危险因素（OR= 2.398和1.804，95% CI 1.084～5.306和1.130～2.880，P= 0.031和0.013）。FT4/FT3、TSH和FT4/FT3联合TSH AUC分别为0.661（95% CI 0.556～0.766，P= 0.004）、0.663（95% CI 0.561～0.764，P= 0.004）和0.726（95% CI 0.632～0.820，P= 0.000）。FT4/FT3和TSH最佳截断值分别为3.346和1.845 mU/L，灵敏度分别为70.5%、62.3%，特异度分别为60.4%、64.6%。FT4/FT3联合TSH的灵敏度和特异度分别为85.2%、50.0%。结论FT4/FT3、TSH是DTC的危险因素，FT4/FT3越大、TSH水平越高，DTC发生风险越高；当FT4/FT3〉3.346和/或TSH〉1.845 mU/L时，联合预测DTC的临床价值较高。

ObjectiveTo investigate the value of free thyroxine （FT4） and free triiodothyronine （FT3） ratio （FT4/FT3） combined with thyrotropin （TSH） in predicting differentiated thyroid carcinoma （DTC）.MethodsThe clinical data of 109 thyroid nodules patients having underwent surgery were retrospectively analyzed. Postoperative pathological findings showed 61 cases of DTC （malignant group） and 48 cases of benign thyroid nodules （benign group）. The independent risk factors of DTC were screened out by univariate analysis and multivariate Logistic regression analysis. The receiver operating characteristic （ROC） curve was drawn. The area under the curve （AUC） was calculated, and the best cut-off value was obtained.ResultsThere was no significant difference in the sex composition and FT4 between malignant group and benign group （P 〉 0.05）. The age and FT3 levels in malignant group were significantly lower than those in benign group： （44.48 ± 12.07） years vs. （52.81 ± 12.99） years and （4.31 ± 0.61） pmol/L vs. （4.73 ± 1.05） pmol/L, the FT4/FT3 and TSH were significantly higher than those in benign group： 3.70 ± 0.62 vs. 3.26 ± 0.70 and 2.15 （1.42, 2.78） mU/L vs. 1.63 （1.05, 2.19） mU/L, and there were statistical differences （P〈0.01 or〈0.05）. Multivariate unconditional Logistic regression analysis result showed that FT4/FT3 and TSH levels were risk factors for DTC （OR= 2.398 and 1.804, 95% CI 1.084-5.306 and 1.130-2.880, P= 0.031 and 0.013）. The AUC of FT4/FT3, TSH and FT4/FT3 combined with TSH were 0.661 （95% CI 0.556-0.766, P= 0.004）, 0.663 （95% CI 0.561- 0.764, P= 0.004） and 0.726 （95% CI 0.632-0.820, P= 0.000）. The best cut-off values of FT4/FT3 and TSH were 3.346 and 1.845 mU/L. The sensitivities were 70.5% and 62.3%, and the specificities were 60.4% and 64.6%. The sensitivity and specificity of FT4/FT3 combined with TSH were 85.2% and 50.0%.ConclusionsFT4/FT3 and TSH levels are risk factors for DTC. The greater the FT4/FT3 level, the higher the TSH level, the higher the risk of DTC. When FT4/FT3〉3.346 and/or TSH〉1.845 mU/L, the clinical value of combined prediction for DTC is higher.