Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA.
Intern Med J. 2012 Nov;42(11):1229-35. doi: 10.1111/j.1445-5994.2011.02604.x.
Cardiotoxicity is a concern in patients on trastuzumab therapy, and cardiac function assessment is a recommended practice. In 2006, trastuzumab was publically subsidised for human epidermal growth factor receptor-2 early stage breast cancer with a requirement for cardiac testing prior to and during treatment.
To investigate the spillover effects of this requirement on testing rates in metastatic patients treated with trastuzumab where no monitoring requirements are applied.
We examined cardiac testing (echocardiography or multiple-gated acquisition scan) in 3779 women with metastatic breast cancer receiving trastuzumab between December 2001 and February 2010 and used interrupted time-series analyses to estimate changes in testing rates. The main outcome measures were the proportion of eligible patients, by quarter, receiving a cardiac function test pretreatment and during trastuzumab therapy.
Only 21% of women had a cardiac function test pretreatment, and 47% were tested at some point during the first year of trastuzumab therapy. The introduction of mandatory cardiac testing for early breast cancer was associated with an immediate 8% increase (95% confidence interval, 2-14%) in pretreatment cardiac testing and an immediate 7% increase (95% confidence interval, 4-10%) in testing during therapy in metastatic patients. Testing rates during therapy increased steadily from early 2005, coinciding with the release of interim results from several trastuzumab trials reporting cardiac-safety outcomes.
The introduction of mandatory cardiac testing for early stage disease spilled over to the metastatic setting. While deviation from guidelines may be warranted in some cases, this study suggests underutilisation of cardiac testing among patients treated with trastuzumab in the metastatic setting.
曲妥珠单抗治疗患者存在心脏毒性问题，因此推荐进行心脏功能评估。2006 年，曲妥珠单抗被用于治疗人表皮生长因子受体-2 早期乳腺癌，并要求在治疗前和治疗期间进行心脏检测。
调查该要求对转移性患者曲妥珠单抗治疗检测率的溢出效应，这些患者没有监测要求。
我们对 2001 年 12 月至 2010 年 2 月期间接受曲妥珠单抗治疗的 3779 例转移性乳腺癌女性患者的心脏检测（超声心动图或多门控采集扫描）进行了检查，并使用中断时间序列分析来估计检测率的变化。主要观察指标是每季度符合条件的患者比例，他们在曲妥珠单抗治疗前和治疗期间接受了心脏功能测试。
只有 21%的女性在治疗前进行了心脏功能测试，47%的女性在曲妥珠单抗治疗的第一年某个时间点接受了测试。早期乳腺癌强制性心脏检测的引入与治疗前心脏检测立即增加 8%（95%置信区间，2-14%）和治疗期间检测立即增加 7%（95%置信区间，4-10%）相关。治疗期间的检测率从 2005 年初开始稳步上升，这与几项曲妥珠单抗试验报告心脏安全性结果的中期结果发布同时发生。
早期疾病强制性心脏检测的引入溢出到转移性环境中。虽然在某些情况下可能需要偏离指南，但本研究表明，在转移性环境中使用曲妥珠单抗治疗的患者中，心脏检测的利用率不足。
