Is blood screening for cancer unethical, particularly in high-risk individuals with a strong family history of cancer or known genetic mutations, such as BRCA2 (Breast Cancer Gene 2)?

Blood Screening for Cancer is Not Unethical in High-Risk Individuals

Blood screening for cancer through genetic testing is ethically appropriate and strongly recommended for high-risk individuals with strong family history or known genetic mutations such as BRCA2, as the benefits of early detection, risk-reducing interventions, and informed decision-making substantially outweigh the risks when proper counseling and informed consent are provided. 1, 2

Ethical Framework Supporting Genetic Testing

The American Society of Clinical Oncology (ASCO) established clear ethical principles affirming that genetic testing for cancer susceptibility is appropriate when three conditions are met: 3

• The person has a strong family history of cancer or very early age of onset 3
• The test can be adequately interpreted 3
• The results will influence medical management of the patient or family member 3

These criteria are specifically met in individuals with BRCA2 mutations or strong family history, making testing not only ethical but medically indicated. 1, 2

Specific Indications for BRCA2 Testing

Genetic testing is explicitly recommended by NCCN guidelines for individuals meeting any of the following criteria: 1, 2

• Personal history of breast cancer diagnosed at age ≤45 years 1, 2
• Breast cancer diagnosed at age ≤50 years with one or more close blood relatives with breast cancer at age ≤50 years 1, 2
• Personal history of epithelial ovarian/fallopian tube/primary peritoneal cancer at any age 1, 2
• Personal history of male breast cancer 1, 2
• Family member with known BRCA1/BRCA2 mutation 1, 2
• Two breast primaries when first diagnosis occurred before age 50 years 1, 2

Tangible Benefits That Justify Testing

The benefits of genetic testing directly improve morbidity, mortality, and quality of life through: 2

• Enhanced surveillance and early detection allowing cancers to be caught at more treatable stages 2
• Risk-reducing interventions including prophylactic mastectomy and salpingo-oophorectomy that substantially reduce cancer incidence 1, 2
• Informed treatment decisions for those already diagnosed, including eligibility for PARP inhibitor therapy in metastatic disease 4
• Cascade testing of family members enabling relatives to benefit from the same risk-reduction strategies 4, 5

For BRCA2 carriers specifically, risk-reducing salpingo-oophorectomy between ages 35-40 provides substantial protection against ovarian cancer, which has high mortality when detected late. 1

Addressing Potential Ethical Concerns

The primary ethical concerns about genetic testing—psychological harm, discrimination, and false reassurance—are mitigated through established safeguards: 3, 6

• Informed consent is mandatory and must include discussion of benefits, limitations, and potential risks 3, 6
• Pre- and post-test genetic counseling addresses psychological impacts and ensures understanding 2, 3
• Anti-discrimination protections should be in place, and ASCO explicitly endorses legislation prohibiting insurance and employment discrimination based on genetic testing 3
• Negative results do not provide false reassurance when proper counseling explains that family history remains important and testing sensitivity is not 100% 5

Critical Implementation Requirements

For genetic testing to remain ethical, these conditions must be met: 3, 2

• Testing should be offered by providers who can adequately communicate benefits, limits, and available prevention/treatment options 3
• Genetic counseling by qualified professionals should be involved early in the process 1, 2
• Results should be used to guide evidence-based management, not simply obtained without action plan 3
• Testing should utilize accredited laboratories with appropriate quality control 3, 7

Population-Level Considerations

While population-wide screening raises different ethical questions, targeted testing of high-risk individuals is fundamentally different because: 8

• The prevalence and penetrance of mutations is substantially higher in high-risk populations 8
• The benefit-to-harm ratio is favorable when mutation probability is elevated 8
• Preventive interventions have demonstrated efficacy in reducing cancer-specific mortality in mutation carriers 1

The ethical framework for cancer screening requires that benefits outweigh harms—this threshold is clearly met in high-risk individuals but may not be met in unselected populations. 8, 9

Common Pitfalls to Avoid

Testing becomes ethically problematic when: 3, 6

• Offered without adequate pre-test counseling about implications 3
• Results are not used to guide medical management 3
• Testing is performed in individuals where results would not change management 3
• Discrimination protections are inadequate 3, 6
• Testing of children is performed when no childhood interventions exist 6

Specific Management for BRCA2 Carriers

Once a BRCA2 mutation is identified, evidence-based management includes: 1

• Annual mammogram and breast MRI starting at age 25 years 1
• Clinical breast examination every 6 months starting at age 25 years 1
• Risk-reducing salpingo-oophorectomy between ages 35-40 after childbearing is complete 1
• For male BRCA2 carriers: prostate cancer screening beginning at age 40 years 1, 4
• Consideration of risk-reducing mastectomy with counseling about degree of protection and reconstruction options 1

These interventions have the potential to substantially reduce cancer-specific mortality, which is the ultimate ethical justification for testing. 1, 2