Old BRCA tests may have missed a cancer-linked mutation

Key Points:

• About 5% to 10% of breast cancer cases are linked to inherited gene mutations, prompting recommendations for all women to complete a risk assessment by age 25 to determine the need for genetic testing.
• Early genetic tests before 2013 often missed many cancer-linked mutations; a recent study found 17.3% of women who initially tested negative were found to have dangerous variants upon retesting years later.
• The 2013 Supreme Court ruling against gene patenting allowed broader, more affordable testing for BRCA1, BRCA2, and up to 50 other cancer-related genes, significantly improving mutation detection.
• Genetic testing is crucial for those with a family history of breast cancer or a personal diagnosis, as identifying mutations can influence treatment decisions, such as opting for mastectomy over lumpectomy or selecting effective medications.
• Experts advise retesting for individuals who had limited genetic screening before 2013, as newer tests provide a more comprehensive understanding of breast cancer risk beyond just BRCA1 and BRCA2 mutations.