RELATIVE RISK OF BREAST CANCER OCCURRENCE BASED UPON KNOWN GENETIC MUTATIONS

Purpose: For women in the United States, breast cancer is the most commonly diagnosed cancer and the second most common cause of cancer death. One in every eight women in the US will develop breast cancer in her lifetime. While the increase in risk for breast cancer due to BRCA1 or BRCA2 genes has been widely reported, relatively little has been reported on the less severe genetic mutations that increase risk of breast cancer. No comprehensive list exists in which each of the genetic mutations known to contribute to breast cancer diagnosis is compared to the normal risk for the general population.

Methods: A comprehensive literature review was conducted to find the risk of breast cancer attributed to a set of genetic mutations. The risk reported for each of these mutations was compared to that reported for specific age groups within the normal population, and relative risk was calculated for each.

Results: A summary table displays the relative risk of each genetic mutation. Calculated relative risks ranged from 1.1 to 21.6. These have been grouped as low, moderate, and high risk mutations.

Conclusion: Physician-patient dialogues regarding breast cancer risk as well as post-diagnosis action plans involve a discussion of patients’ relative risk of acquiring breast cancer. When consulting genetically-predisposed patients regarding contralateral prophylactic mastectomy, understanding each patient’s relative risk of contralateral breast cancer is essential. We anticipate this comprehensive list of relative risk of various breast cancer-affiliated genetic mutations to be important for breast cancer-related decision-making protocols.