Using Breast Cancer Index to Make Decisions About Extended Endocrine Therapy

By: Victoria Kuhr, MS
Posted: Thursday, May 30, 2024

Joyce A. O’Shaughnessy, MD, of Baylor University Medical Center, Dallas, and colleagues reported that the Breast Cancer Index (BCI) supports previous study findings on the impact of using this clinical tool to select patients for extended endocrine therapy based on an individualized risk/benefit analysis. Additionally, researchers observed that incorporating BCI into clinical practice resulted in changes in physician recommendations; increased physician confidence; improved patient satisfaction; and reduced patient concerns regarding the cost, drug safety, and benefit of extended endocrine therapy. These findings were published in JNCCN–Journal of the National Comprehensive Cancer Network.

“[O]ncology guidelines such as those from the National Comprehensive Cancer Network and American Society of Clinical Oncology recognize BCI as the only predictive genomic assay for making endocrine therapy decisions,” said the study authors.

The BCI Registry study evaluated the long-term outcomes, decision impact, and medication adherence in patients receiving BCI testing as part of their routine clinical care. Physicians and patients completed pre-BCI and post-BCI test questionnaires. Questions included physician decision-making and confidence regarding endocrine therapy; patient preferences and concerns about the cost, side effects, drug safety, and benefit of endocrine therapy; and patient satisfaction regarding treatment recommendations.

The pre-BCI and post-BCI questionnaires were completed by 843 physicians and 823 patients. Of the 823 patients, 88.4% were postmenopausal. Of the tumors, 74.7% were T1, 53.4% were grade 2, 76.0% were N0, and 13.8% were HER2-positive. Following BCI testing, physicians changed endocrine therapy recommendations in 40.1% of patients (P < .0001), and 45.1% of patients changed their preferences for endocrine therapy (P < .0001). In addition, 38.8% of physicians felt more confident in their recommendation (P < .0001), and 41.4% of patients were more comfortable with their endocrine therapy decision (P < .0001). Compared with baseline, significantly more patients had fewer concerns about cost (20.9%; P < .0001), drug safety (25.4%; P = .0014), and benefit of endocrine therapy (29.3%; P = .0002).

Disclosure: For full disclosures of the study authors, visit jnccn.org.

JNCCN–Journal of the National Comprehensive Cancer Network

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