In the United States, breast cancer continues to rank as the most common cancer in women, irrespective of race or ethnicity. It is predicted that 12% of women in the United States will develop breast cancer over the course of her lifetime.
While the death rate of breast cancer continues to remain high, the survival rate has greatly improved over the years thanks to new screening guidelines and treatment. It is estimated that the survival rate has tripled over the past 60 years and are improving faster than any other cancer.
Worldwide nearly 1.7 million new cases of breast cancer were diagnosed in 2012. This represented 25% of all new cancer diagnoses in women and 12% of all new cancer cases in both sexes. Belgium had the highest rate of breast cancer at 111.9 new cases per 100,000 people. The United States ranked 9th in rate of breast cancer diagnosis, with 92.9 new cases per 100,000 people. Generally, the developed world experiences a much higher rate of breast cancer, with lower rates found throughout Asia and Africa. Breast cancer is the number one cause of cancer deaths in Hispanic women and the second most common cause of cancer deaths among white, black, Asian/Pacific Islander, and American Indian/Alaska Native women.
Men are not exempt from this disease, with 2,125 new breast cancer cases diagnosed in men and 405 male deaths occurring in the United States during 2012. Although commonly viewed as a female disease, a man’s lifetime chance of developing breast cancer is around 1 in 1000. Therefore it is important for men to be aware of breast cancer screening methods and to be checked by a doctor if they notice any unusual breast lumps.
Risk Factors for Breast Cancer
The risk of developing breast cancer is influenced by genetic, personal, and behavioral factors. Some of these factors are modifiable (within the individual’s power to change) while other factors are nonmodifiable (not able to be changed). Modifiable factors include lifestyle, weight, birth control choices, diet, smoking, substance abuse, etc. Nonmodifiable factors include genetics age, sex, the age of first period (menarche), the age of last period (menopause), and environmental pollution.
Genetic factors including mutations within the body’s entire genome or just the tumor itself can result in a higher risk of developing breast cancer. The most well known genetic abnormalities that increase the risk for breast cancer are the Breast Cancer gene 1 and 2 (BRAC1 or BRACA2). These genes are inherited from family and result in a 60% increased risk of developing breast cancer. This is considerably higher than the 12% overall risk for a woman in the general population. There are a number of other genes that have been associated with a higher risk of developing breast cancer, although the mechanisms behind their function are less studied. These include mutations in the ATM, p53, CHEK2, PTEN, and CDH1 genes.
Genetic mutations and abnormalities are inherited, and therefore nothing can be done to prevent the increased risk of developing breast cancer. However, if a patient is identified to be a carrier of any of these particular mutations, then the patient’s doctor can implement additional screening and monitoring methods for early identification of breast cancer. This assists in identifying the disease in a timely manner and therefore potentially preventing its invasion and spread into other adjacent tissues or bodily organs.
Age is one factor that is strongly linked to the development of breast cancer. As women age their risk of developing breast cancer increases. Age is not only pertaining to the number of years lived, but also the age of first childbirth and period. Having your first child after the age over 30, having your first period before the age of 12, or starting menopause later than 55years of age will all increase the risk of breast cancer. Therefore age at a number of major life events greatly impacts one’s breast cancer risk.
Ethnicity is another indicator of breast cancer risk. Caucasian women are slightly more likely to develop the breast cancer as opposed to other ethnicities. African American women, on the other hand, are more likely to develop breast cancer before the age of 45. They are also more likely to die from the disease at any age. Asian, Hispanic, and Native American women generally have a lower risk of developing or dying from breast cancer.
Breast tissue with added density can increase the risk of developing breast cancer by 1.2 to 2 times compared women with standard breast density. Breast density is measured by comparing the amount of fatty, fibrous, and glandular tissues present in the breast. Women with more of these breast characteristics tend to have a higher risk of developing breast cancer.
The use of birth control increases the risk of breast cancer. While it decreases the risk of uterine cancer.
Behavioral factors that include regular alcohol consumption and smoking increase the risk of developing breast cancer. Drinking between two and five drinks a day can increase the risk of developing breast cancer by 1.5 times that of a non-drinker. Night work, which includes late night or overnight work, also increases the risk of breast cancer.
Some behavior factors can also decrease risk of breast cancer. These activities include breastfeeding, eating lots of fruits and vegetables, exercising both before and after menopause, and maintaining a healthy weight. Consumption of carotenoids, which are the pigments that make foods like carrots, melons, and sweet potatoes appear orange, can also decrease the risk breast cancer.