Risk factors for breast cancer
Genetics and Family History
There are many risk factors for breast cancer. Genetics, especially the BRCA genes: BRCA1 and BRCA2, play a significant role in causing breast cancer. As many as 10% of all breast cancers may be caused by BRCA gene mutations. Another 10% may be caused by other genetic mutations outside the BRCA genes. Having a close relative, mother, sister, or daughter with breast cancer doubles an individual’s risk. In India, the prevalence of BRCA mutations over a large population is unknown.
Personal Breast Cancer History
A women who has had breast cancer in one breast (unilateral) has a significantly greater than normal chance of developing breast cancer in her other breast. This risk may be even greater in women with a history of cancer and carrying a BRCA mutation.
Age
Environmental and lifestyle factors can lead to breast cancer. Outside of those with genetic risks, the highest risk group to develop breast cancer is women over 50 years old.
Physical traits, menstruation and pregnancy
Denser breasts, hitting puberty early, hitting menopause late, and having lumps in breasts are thought to increase risk to breast cancer. These factors however, have been also contradicted by several studies, so they may be less prevalent than other factors. Completing a pregnancy and breast feeding may lower the risk of breast cancer. Similarly, women who never get pregnant may be at a higher risk.
Ethnicity
Ethnicity plays a role in how prone a woman is to breast cancer. Studies have shown that Caucasian women for example, may be at greater risk than African American women. Unfortunately, no large scale studies have been done (to the best of our knowledge) to determine the risk in Indian women relative to other racial groups.
Factors which contribute to overall increased cancer risks
Several known factors which contribute to an increased risk for cancer, which can include breast cancer are: smoking and/or alcohol consumption, obesity (or being overweight), and lack of physical activity such as exercise.
