Interest in genetic testing for modest changes in breast cancer risk: implications for SNP testing
K D Graves1, B N Peshkin, G Luta
1Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC 20007, USA. kdg9 @ georgetown.edu
Public Health Genomics
|April 6, 2011
Summary
Interest in genetic testing for breast cancer risk was high among women, influenced by perceived risk and cost. Many women lacked understanding of risk, impacting their willingness to pay for genetic tests.
Area of Science:
- Genomics
- Medical Genetics
- Cancer Epidemiology
Background:
- Personalized genetic medicine holds promise, but the clinical utility of predictive genetic testing for modest risk changes remains uncertain.
- Understanding women's interest in genetic testing for genes associated with moderate breast cancer risk is crucial for clinical implementation.
Purpose of the Study:
- To explore women's interest in genetic testing for genes linked to modest changes in breast cancer risk.
- To assess factors influencing interest, willingness to pay, and comprehension of genetic test results.
Main Methods:
- Telephone surveys were conducted with 105 women with a negative breast biopsy and a family history of breast or ovarian cancer.
- Participants were presented with hypothetical genetic testing scenarios for lower-penetrance breast cancer mutations.
- Logistic regression models evaluated the influence of risk level, cost, and behavioral modifiers on testing interest.
Main Results:
- A significant majority of women (77%) expressed definite interest in genetic testing, with higher interest for tests conveying more risk and lower cost.
- Interest was influenced by behavioral risk modifiers, physician relationship, perceived benefits, and cancer worry.
- Comprehension of relative versus absolute risk was low (63%), and lower understanding correlated with increased cancer worry and willingness to pay.
Conclusions:
- High interest in genetic testing for modest risk changes was observed, modulated by test characteristics and psychosocial factors.
- The findings underscore the need for enhanced education regarding the benefits and risks of genetic testing for mutations conferring modest risk.
- This is particularly important given the current limitations in clinical validity/utility and the rise of direct-to-consumer genetic testing.
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