Knowledge of risk factors and modes of gene transmission among women at risk for hereditary breast and ovarian cancer syndrome

Background: Hereditary Breast and Ovarian Cancer (HBOC) is a collective term used to describe genetic susceptibility to breast and/or ovarian cancer. Most HBOC cases are attributed to BRCA1 and BRCA2 genes (BRCA1/2). Once a case of HBOC is identified, the risk of carrying a BRCA1/2 mutation and its implications extends to family members. This study examined whether female relatives from HBOC families can identify risk factors associated with HBOC and modes of BRCA1/2 gene transmission. Methods: This quantitative, descriptive, cross-sectional study assessed frequencies of correct responses to 19 items assessing knowledge of HBOC risk factors and 17 items assessing knowledge of modes of gene inheritance. All items have been previously validated. The sample consisted of 172 women, who based on pedigree analysis had >10% of carrying an-HBOC predisposing genetic mutation, but had NOT pursued genetic testing. Results:The majority of items assissing risk factors associated with HBOC were correcty identified by more than 50% of respondents. Sporadic occurence of breast cancer was correctly identified by 95% of the sample. Of the 17 items assessing knowledge of gene mutation transmission, 2 items were correctly identified by 87% of participants: that inherited and non-inherited mutations can cause cancer, and that genetic testing cannot predict risk of developing cancer. Approximately 50% knew that men can pass on a BRCA1/2 mutation to their children, and correctly identified all family history signs indicative of a mutation-harboring family. Fewer women (<35%) correctly identified the numeric probabilities of developing HBOC and of passing on a BRCA1/2 mutation to offspring. Conclusions: Educational interventions are needed to educate women at risk for HBOC. Identifying appropriate information dissemination information strategies to target these women should be a priority for healthcare providers. These strategies should also focus on encouraging communication among women at high risk for HBOC and their family members.