Knowledge of genomic testing among early-stage breast cancer patients.

BACKGROUND: Genomic recurrence risk test results now inform clinical decisions about adjuvant treatment for women with early-stage breast cancer. We sought to understand patients' knowledge of these tests and correlates of their knowledge.
METHODS: Participants in this cross-sectional study were 78 women, treated for early-stage, estrogen receptor-positive breast cancer with 0-3 positive lymph nodes, whose medical records indicated they received Oncotype DX testing earlier. We mailed a questionnaire that assessed knowledge of genomic recurrence risk testing (13 item scale, alpha=0.83) and reviewed medical charts of consenting patients.
RESULTS: Knowledge about genomic recurrence risk testing was low (mean knowledge score=67%, SD=0.23). Low knowledge scores were more commonly due to responses of 'don't know' than incorrect answers. Most women (91%) clearly understood that test results can aid decisions about chemotherapy, and few (22%) understood that the test's estimate of the chance of metastasis assumes the patient is receiving hormone therapy. Higher knowledge about genomic recurrence risk testing was associated with higher education, reading ability, and numeracy. Knowledge was higher among women who recalled receiving both verbal and printed information about the test and among women who had active roles in deciding about their treatments. Higher knowledge was also associated with having fewer concerns about genomic testing. DISCUSSION: Among early-stage breast cancer patients who received Oncotype DX, we found low knowledge about many aspects of genomic recurrence risk testing. Research is needed to understand testing information provided to patients and best practices for patient education.