目的 探讨胸腺肽β4（Tβ4）在化疗相关心脏毒性中的诊断价值。方法 采用双抗体夹心ELISA法测定129例乳腺癌化疗患者血清Tβ4浓度，分析其化疗前后浓度变化与心脏毒性发生的相关性，分析其诊断心脏毒性的敏感性与特异性。结果 共18例(13.95%)患者出现心脏毒性，心脏毒性组患者血清中Tβ4水平显著高于无毒性组（P<0.01）；根据ROC曲线，Tβ4诊断乳腺癌化疗后心脏毒性的曲线下面积为0.829（95% CI: 0.709-0.937）,综合考虑ROC曲线，设血清Tβ4水平6000pg/mL为诊断心脏毒性的临界点，其诊断乳腺癌心脏毒性的敏感性和特异性分别为72.22%、85.60%。结论 本研究证实Tβ4在早期诊断心脏毒性的应用价值，提示其可能成为较理想的心脏毒性诊断的血清标志物。

Objective To study the diagnostic value of serum Thymosin β4 level on chemotherapy-related cardio-toxicity of breast cancer. Methods The double antibody sandwich ELISA was used to detect serum Tβ4 level in 129 breast cancer patients and analysis if ECG was associated with chemotherapy-related cardio-toxicity. The sensitivity and specificity of ECG in the diagnosis the cardio-toxicity was assessed. Results A total of 18 patients (13.95%) had subsequent claims for cardio-toxicity events. Tβ4 in cardio-toxicity group was significantly higher than that non-cardio-toxicity group (P <0.01). According to ROC curve, the cut off value of Tβ4 was set at 6000pg/mL, the specificity and sensitivity were 72.22％ and 85.60％ respectively．Conclusion The present study is to confirm excellent clinical value of Tβ4 on cardio-toxicity. The level of Tβ4 for early detection of cardio-toxicity has good prospects for high-risk patients.