Final answer:
Women are at a higher risk for developing breast cancer due to inherited risk factors, particularly mutations in BRCA1 and BRCA2 genes, which increase the risk significantly. These genetic factors, coupled with environmental influences, contribute to the likelihood of cancer development, despite the absence of a family history of the disease. Early detection through routine mammograms plays a critical role in successful treatment outcomes.
Step-by-step explanation:
Factors Increasing the Risk for Breast Cancer in Women
Women face various risk factors that increase their likelihood of developing breast cancer. Inherited risk factors such as mutations in the BRCA1 and BRCA2 genes significantly elevate the risk of breast and ovarian cancer. While these genetic mutations do not guarantee the development of cancer, they substantially raise the odds, with up to a 75 percent increased risk for those carrying the mutation. It's crucial to note, however, that these genes are responsible for fewer than 10 percent of all human cancers.
Environmental factors also contribute to breast cancer risk, although they play a less significant role compared to high-impact genetic mutations. A family history of cancer, including occurrences of breast cancer at an early age and in multiple close relatives, suggests an inherited predisposition. Routine screening mammograms, particularly for women aged 50 and older, are important for early detection as early-stage breast cancer is often curable with surgery.
Unlike Rebecca's assumption in the given scenario, not having a family history of cancer does not eliminate the genetic risk. Individuals with harmful BRCA1 mutations have a 55 to 65 percent chance of developing breast cancer by age 70, contrasting with 12 percent in the general population. The cancers may still be genetic even if not everyone in a family inherits the mutations or develops cancer.