New research presented at the American Society of Clinical Oncology (ASCO) meeting in Chicago yesterday suggested that genetic mutations associated with breast cancer may be more common among black African American women than previously expected.
The more aggressive forms of breast cancer that typically occur in women under 45 are more common among black women than other ethnic groups in the US; black women are 40% more likely to die from the disease than white women.
Researchers used a test that examined a panel of 18 breast cancer susceptibility genes in 249 black women with triple-negative breast cancer Chicago; 22% of the women tested had at least one mutation in these genes. 79% of the mutations affected the BRCA1 and BRCA2 genes.
Of note, the precise nature of mutations in the different genes was highly variable between women, suggesting that a test that looked only for a small number of common mutations would not be suitable for this population.
The experts emphasised that the findings did not mean that most black women were at risk, but rather that it was important for black women who present with early onset or aggressive (triple-negative) breast cancers, or with a family history of breast and ovarian cancer, should be referred for genetic counselling and testing.
Comment: Genetic factors do need to be examined in different test populations as findings from one group are not necessarily applicable to another, a vital issue when planning standardised genetic tests or screening programmes. These latest findings add further emphasis to the need for cancer patients with features characteristic of inherited cancer syndromes to be referred for genetic investigation, since relatives may also be at risk and in need of increased surveillance or preventative interventions (see previous news).