Early detection of breast cancer not only has a high cure rate, but also allows breast-conserving surgery and reduces various adjuvant treatments after surgery, which not only saves patients’ medical costs, but also has a high quality of life. Therefore, primary prevention (etiology prevention) and secondary prevention (early diagnosis) of breast cancer are of great importance to the prognosis of breast cancer.
Many risk factors
No definite culprit
There are many risk factors for breast cancer, and although a lot of research has been done at home and abroad, the main causative factors have not been clearly identified so far. However, it is certain that the combination of multiple risk factors will lead to an increased risk of breast cancer.
Genetic factors
Family history of breast cancer The risk of breast cancer for one person in the immediate family (mother, sister, daughter) is increased by one, and for two people, the risk is increased by five. The younger the relative, the greater the risk of the disease.
Studies have shown that BRCA carriers have a greater risk of developing breast cancer at any age than non-carriers, with a higher risk of developing the disease at a younger age.
Environmental factors
1. Physical environmental factors
Studies have shown that breast tissue is sensitive to ionizing radiation and is susceptible to radiation damage. In the United States, a follow-up study was conducted on 90,305 people working with radiation and the incidence of breast cancer in women was significantly higher.
2.Life environment factors
Dietary factors: Studies have shown that a high-fat diet increases the risk of breast cancer in postmenopausal women. In terms of high-sugar diet, studies are still controversial: some studies suggest that the intake of carbohydrates containing high sugar is not associated with breast cancer risk in postmenopausal women; others show that higher intake of sweets increases breast cancer risk in women <45 years old.
Menstrual cycle: Early age at menarche, long interval between menarche and menarche, short menstrual cycle, disrupted menstrual cycle, and late menopause are risk factors for breast cancer. A multicenter study of 290,000 women showed that the risk of breast cancer at age <12 years at menarche was 1.3 times higher than that at age >15 years; the risk of breast cancer in women who had menopause at age >55 years was 1.22 times higher than that in women who had menopause at age <45 years; and the risk of breast cancer was 45% lower in those who had bilateral oophorectomy at age <40 years than in those who had natural menopause at age 50-54 years. Studies have shown that the longer the breast is exposed to endogenous estrogens, the higher the risk of breast cancer.
Childbirth and breastfeeding: Late age at first birth, few full-term births, and lack of childbearing are risk factors for breast cancer, while a history of breastfeeding is a protective factor. The risk of breast cancer increases approximately 3-fold in women who have their first child >35 years of age compared to those who have their first child <20 years of age. This is because the first pregnancy leads to a series of changes in the breast epithelium that matures, and mature breast epithelial cells are more resistant to genetic mutations. Increasing age at first birth increases the risk of breast cancer, with the risk being 1.67 and 2.23 times higher for women who do not have children and for women >35 years of age, respectively, than for women <20 years of age who have their first child.
Estrogen replacement therapy: Studies have shown that the risk of breast cancer increases with the duration of HRT use, with a 1.35-fold increase in the risk of breast cancer for those who have used HRT for ≥5 years. Therefore, HRT use should be weighed against the possible risks and benefits and should be used for less than 5 years.
Etiology prevention: focus on a healthy lifestyle
Proper diet structure
Recommendations: control the intake of animal fat and animal protein, and consume vegetable fat appropriately; eat more fruits, vegetables, beans, mushrooms and fish; drink less alcohol; limit the intake of smoked food; eat less salt, less than 6 g of salt per day for adults; eat more fresh food and less canned food; keep food fresh, freeze and refrigerate food, and do not hide food for a long time; cook scientifically and do not eat burnt food; quit smoking; reduce the risk of breast cancer. Reduce the intake of extra sugar (e.g. carbonated drinks, edible sugar, cakes and desserts, etc.), saturated fatty acids (e.g. animal fat, etc.) and trans fatty acids (e.g. fried and puffed foods, etc.).
Weight control and appropriate physical activity
Overweight, obesity and weight changes in adulthood have a significant impact on the development of breast cancer, especially postmenopausal breast cancer. Overweight and obesity can be controlled through lifestyle changes, so controlling body mass and physical activity can effectively reduce abdominal fat and control obesity, and control excessive weight gain in adulthood, thus effectively preventing breast cancer. The only scientific approach to weight control is a balanced diet plus physical activity. For most adults, reducing caloric intake by 50 to 100 kcal per day will prevent continued weight gain. For weight loss, reduce caloric intake by 500 kcal per day. Physical activity should be at least 30 min of moderate to vigorous physical activity at least 5 days a week, with 45-60 min of activity being ideal.
Promote breastfeeding
Breastfeeding is an effective way to reduce the incidence of breast cancer by avoiding marriage and childbirth at an advanced age.