Aims

Trastuzumab, one of the best known examples of personalized medicine, requires regular cardiac monitoring because it can cause heart failure. We aimed to assess the utilization of cardiac monitoring in women with nonmetastatic breast cancer receiving trastuzumab-based chemotherapy in routine clinical practice.

Patients & methods

The medical records of women continuously enrolled in a large national health insurance plan who were diagnosed with nonmetastatic breast cancer and treated with trastuzumab from 2006 to 2008 were reviewed (n = 109). The primary outcome variables were the use and type of cardiac monitoring testing before and during trastuzumab therapy. An exploratory multivariable logistic regression analysis was performed to identify predictors for receiving cardiac monitoring both at baseline and during trastuzumab treatment.

Results

Monitoring both before and during therapy was less common (62%), although 74% had cardiac monitoring before therapy and 80% had at least one test during therapy. Radionuclide ventriculogram was utilized more often than echocardiography (48 vs 42%). Only the use of anthracycline (odds ratio: 2.39; 95% CI: 1.01-5.71) was significantly associated with use of a cardiac monitoring both at baseline and during trastuzumab treatment.

Conclusion

The use of cardiac monitoring testing was variable and opportunities to improve quality and reduce cost are evident. These results have clinical implications for other personalized medicine interventions requiring regular laboratory monitoring.

Background

Among patients with stage I breast cancer, there is significant uncertainty concerning the optimal threshold at which to consider chemotherapy, and when considered, there is controversy regarding whether to consider non-intensive versus intensive regimens. The authors examined the types and costs of adjuvant chemotherapy received among patients with stage I breast cancer.

Methods

The current study was a prospective cohort study including patients with stage I breast cancer who were treated at a National Comprehensive Cancer Network center from 2000 through 2009. Stage was defined according to the version of the American Joint Committee on Cancer Staging Manual applicable at the time of diagnosis. Stratifying by human epidermal growth factor receptor 2 (HER2), the authors examined the percentage of patients receiving intensive versus non-intensive chemotherapy regimens and the factors associated with type of chemotherapy administered using multivariable logistic regression. Costs of the most common regimens were estimated.

Results

Of 8907 patients, 33% received adjuvant chemotherapy. Among those individuals, there was an increase in the use of intensive chemotherapy within the last decade, from 31% in 2000 through 2005 to 63% in 2008 through 2009 (including an increase in the use of the combination of docetaxel, carboplatin, and trastuzumab) among patients with HER2-positive disease and from 15% in 2000 through 2005 to 41% in 2008 through 2009 among patients with HER2-negative disease (32% of patients with hormone receptor-positive and 59% of patients with triple-negative disease). Among patients treated with non-intensive regimens, there was an increase in the use of the combination of docetaxel and cyclophosphamide noted, with a decrease in the use of the doxorubicin and cyclophosphamide combination. The choice of regimen varied significantly by institution. The major drivers of cost variation were the incorporation of biologics (eg, trastuzumab) and growth factors, with significant variation even within non-intensive and intensive regimens.

Conclusions

Over time, there was an increase in use of intensive regimens among Stage I breast cancer, with striking institutional and cost variations.