What are the risk factors for breast cancer?

1. What are risk factors? A risk factor is any factor that may affect the likelihood of developing a disease, such as breast cancer. But just because you have one or more risk factors doesn’t mean you’re going to get it. Late childbearing 40%, early menarche and delayed menopause or obesity 8-30%, drinking and smoking 15-25%, family history 15-20%, increased breast density 9-16%, gene mutation BRCA 5-10%. 2. Classification of risk factors (1) Breast cancer risk factors that you can’t change: female (gender is an important risk factor, women are much higher than men), age (most women are diagnosed over 50 years old), history of breast cancer (risk of recurrence of contralateral breast; Lobular origin, morbidity age < 40 years, higher risk of recurrence), ethnicity/race (white women are at slightly higher risk than African American women, Asian women are at lower risk), family history (15-20% of patients have family history. The more the number of patients in the immediate family/the younger the age, the greater the risk of the disease), dense breast tissue (mammography for dense items has a higher risk of the disease), benign breast disease (simple proliferative lesions increase the risk of the disease, atypical hyperplasia increases the risk of the disease), early menarche age (menarche 55 years, increased risk of breast cancer), hormone exposure/radiotherapy (increased risk after DES, increased risk after chest radiotherapy). Breast/chest X-ray and other examinations do not significantly increase the risk of disease). (2) Lifestyle-related breast cancer risk factors: alcohol consumption (alcohol consumption increases the risk of breast cancer in women, and the more alcohol consumption, the higher the risk.) Being overweight or obese (after menopause) increases a woman’s risk of developing breast cancer. In the Asia-Pacific region, the risk of breast cancer increases by 18% for every 5/m2 increase in adult women’s BMI), lack of exercise (lack of physical exercise, such as sedentary lifestyle, increases the risk of breast cancer, and moderate physical activity can reduce the risk of breast cancer. Exercise may affect the amount of estrogen and progesterone in women, which can reduce the efficiency of fat conversion into estrogen in postmenopausal women. In addition, exercise can also improve your immunity. Thus, exercise may reduce the risk of breast cancer.) Women who have never been pregnant or who have had their first child after the age of 30 have about twice the risk of breast cancer as women who have given birth before the age of 30. Multiple pregnancies and pregnancies at a younger age can reduce the risk of breast cancer. Women who choose to breastfeed can reduce their risk of breast cancer.)