We have known for a while that many people who have mutations in BRCA1/2 and other inherited cancer risk genes are unaware of their mutation as they have not yet had genetic testing. A recent study among women aged 20 or older living in California and Georgia, which included almost 80,000 breast cancer patients and 6,000 ovarian cancer patients, found that about a quarter of those with breast cancer and a third of those with ovarian cancer had genetic testing [1]. Of individuals who had testing, 7.8% of those with breast cancer and 14.5% with ovarian cancer were found to have a mutation in an inherited cancer gene [1]. Testing among breast cancer patients was lower as age and poverty level increased, but was similar across racial/ethnic groups (such as Whites, Blacks, American Indians, Asians, and Hispanics) [1]. In contrast, for ovarian cancer patients, testing was lower among Black compared to White patients (21.6% versus 33.8%) and among those without insurance compared to those with insurance (20.8% versus 35.3%) [1]. These results continue to identify substantial gaps in testing among cancer patients, and highlight existing disparities in cancer care which need to be addressed and improved.
Findings from another study based in a health system where patients were insured and had access to genetic services were recently published [2]. Results showed that annual rates of genetic testing increased between 2005 to 2015 among women with breast and ovarian cancer overall; however, rates of genetic testing among women with newly diagnosed breast and ovarian cancers fell from 71.5/1000 person years in 2005 to 44.4/1000 person years in 2015 [2]. This study highlights that many women who are eligible to have BRCA1/2 testing covered by their health insurance did not have it, suggesting there is much work to be done for more people to benefit from testing and the medical care options that testing may provide.
[1] Kurian, et al. J Clin Oncol. 2019 May. PMID 30964716; [2] Knerr, et al. J Natl Cancer Inst. 2019 Feb. PMID 30753636.