The Value of Personalizing Medicine: Medical Oncologists’ Views on Gene Expression Profiling in Breast Cancer Treatment

OBJECTIVES: Guidelines recommend gene-expression profiling (GEP) tests to identify early-stage breast cancer patients who may benefit from chemotherapy. However, variation exists in oncologists' use of GEP. We explored medical oncologists' views of GEP tests and factors impacting its use in clinical practice. METHODS: We used a qualitative design, comprising telephone interviews with medical oncologists (n = 14; 10 academic, 4 in the community) recruited through oncology clinics, professional advertisements, and referrals. Interviews were analyzed for anticipated and emergent themes using the constant comparative method including searches for disconfirming evidence. RESULTS: Some oncologists considered GEP to be a tool that enhanced confidence in their established approach to risk assessments, whereas others described it as "critical" to resolving their uncertainty about whether to recommend chemotherapy. Some community oncologists also valued the test in interpreting what they considered variable practice and accuracy across pathology reports and testing facilities. However, concerns were also raised about GEP's cost, overuse, inappropriate use, and over-reliance on the results within the medical community. In addition, although many oncologists said it was simple to explain the test to patients, paradoxically, they remained uncertain about patients' understanding of the test results and their treatment implications. CONCLUSION: Oncologists valued the test as a treatment-decision support tool despite their concerns about its cost, over-reliance, overuse, and inappropriate use by other oncologists, as well as patients' limited understanding of GEP. The results identify a need for decision aids to support patients' understanding and clinical practice guidelines to facilitate standardized use of the test.