Adoption of Gene Expression Profile Testing and Association With Use of Chemotherapy Among Women With Breast Cancer

Abstract

A B S T R A C T PurposeGene expression profile (GEP) testing is a relatively new technology that offers the potential of personalized medicine to patients, yet little is known about its adoption into routine practice. One of the first commercially available GEP tests, a 21-gene profile, was developed to estimate the benefit of adjuvant chemotherapy for hormone receptor-positive breast cancer (HR-positive BC). Patients and MethodsBy using a prospective registry data set outlining the routine care provided to women diagnosed from 2006 to 2008 with HR-positive BC at 17 comprehensive and community-based cancer centers, we assessed GEP test adoption and the association between testing and chemotherapy use. Overall, testing was associated with lower odds of chemotherapy use (OR, 0.70; 95% CI, 0.62 to 0.80). Stratified analyses demonstrated that for small, node-negative cancers, testing was associated with higher odds of chemotherapy use (OR, 11.13; 95% CI, 5.39 to 22.99), whereas for node-positive and large node-negative cancers, testing was associated with lower odds of chemotherapy use (OR, 0.11; 95% CI, 0.07 to 0.17). Results ConclusionThere has been a progressive increase in use of this GEP test and an associated shift in the characteristics of and overall reduction in the proportion of women with HR-positive BC receiving adjuvant chemotherapy.

Recommendations from the EGAPP Working Group: does the use of Oncotype DX tumor gene expression profiling to guide treatment decisions improve outcomes in patients with breast cancer?

“…The test is now in use in many clinical centers. 2,3 However, until definitive evidence for clinical utility is available, clinicians must decide on a case-by-case basis whether to offer the test to individual patients.…”

“…A survey of the care of 7,375 women treated at 11 comprehensive cancer centers and six community-based cancer centers in the United States found an overall decrease in chemotherapy use from 53.9 to 47.0% (P < 0.001). 3 A survey of 6,229 patients registered on an electronic health record database found an association between RS and chemotherapy use (P < 0.001). 34 • In these surveys, approximately 37% of patients were in the intermediate-risk category, for whom chemotherapy benefit is uncertain, compared with 22% in the initial studies by Paik et al 3,23,34 The prospective TAILORx trial 35,36 focuses on the intermediate-risk group, but the trial is not scheduled for completion until 2017.…”

Uptake of a 21-Gene Expression Assay in Breast Cancer Practice: Views of Academic and Community-Based Oncologists

“…Although the results of health technology assessments raise questions about the clinical utility of the 21-gene expression assay, medical oncologists are using test results in clinical practice to help inform decision-making with respect to patients who can safely avoid adjuvant chemotherapy [10][11][12] . The short-and long-term risks of adjuvant chemotherapy have been well documented, and there are concerns about the overtreatment of patients having breast cancer with low-risk features 13 .…”

“…Research in this area can yield valuable information about how oncologists use new technologies in less-controlled, non-research settings. For example, Hassett et al 11 used a prospective registry that collected data from 17 comprehensive and community cancer centres to assess gep test adoption for women diagnosed with breast cancer between 2006 and 2008. They found that gep testing increased over time, with an overall reduction in use of adjuvant chemotherapy in hormone receptorpositive breast cancer.…”

“…They found that gep testing increased over time, with an overall reduction in use of adjuvant chemotherapy in hormone receptorpositive breast cancer. Although most tests were ordered for patients with intermediate-risk cancer, 20% of tests were ordered for patients in whom testing is not recommended according to the U.S. National Comprehensive Cancer Network guideline 11 . The same authors also found that chemotherapy was sometimes ordered even when gep test results indicated that the risk was low; the converse was also true, in that chemotherapy was not provided when gep test results indicated that the risk was high.…”