The incidence of breast cancer is the highest among female malignant tumors. Breast cancer accounts for 24.2% of the total number of malignant tumors, and the incidence rate of people in different regions is different. The more developed areas, the higher the incidence of breast cancer. In rural areas, or backward or underdeveloped areas, the incidence rate is relatively low. The highest incidence rate is in developed countries such as Europe and America, and the incidence rate can reach about 70 per 100,000 per year.

In China's coastal areas and big cities, such as Beijing and Shanghai, the incidence rate can reach 65,438+40 per 100,000, or even more than 40. In rural or inland areas, the incidence rate is 65438+20-30 per 100,000, or even lower. Generally speaking, the incidence of breast cancer is on the rise, but the cure rate is also on the rise, and the mortality rate is on the decline.

Causes of inducing breast cancer

1. According to relevant medical research, menarche is early and menopause is late. The age of menarche is less than 12 years old. Compared with the age of menarche is greater than 17 years old, the relative risk of breast cancer increases by 2.2 times. The risk of breast cancer in people with amenorrhea over 55 years old is twice as high as that in people with amenorrhea under 45 years old. Early menarche and late menopause are the two most important risk factors for breast cancer.

2. Genetic factors. The study found that if her mother had bilateral breast cancer before menopause, the risk of breast cancer was 9 times that of ordinary women, and the average age of the second generation of breast cancer patients was about 10 years earlier than that of ordinary women. Women with breast cancer among sisters are three times more dangerous than ordinary people. It should be emphasized that breast cancer is not a direct inheritance, but a "cancerous" inheritance. Relatives of breast cancer patients may not have breast cancer, but their chances of getting breast cancer are higher than those of ordinary people.

3. Bad marriage and childbearing. Epidemiological studies show that although women are infertile after marriage or give birth to their first child after the age of 30, the risk of breast cancer among unmarried people is twice that of married people. Experts believe that childbirth can protect breasts, but it only refers to people who give birth at full term before the age of 30. Recent studies have shown that breastfeeding has a protective effect on breast cancer, especially for premenopausal women.

4. Ionizing radiation. Breast is a tissue sensitive to ionizing radiation and carcinogenic activity. When young, it is the mitotic stage of breast, and it is most sensitive to the carcinogenic effect of ionizing radiation, and the effect of ionizing radiation is cumulative. The risk of repeated low-dose exposure is the same as that of high-dose exposure, and there is a dose-effect relationship.

5. Unhealthy eating habits. The incidence and mortality of breast cancer are closely related to the amount of digestible fat per capita. The high income of employees in some companies leads to a high standard of living, forming an unscientific and unhealthy eating habit of "high calorie and high fat", which leads to a great increase in the incidence of breast cancer.

6. Unhealthy lifestyle. Some female white-collar workers who have been engaged in office work for a long time sit more and move less, lack exercise and get less sunshine. Most professional women hold their bras tightly for a long time because of their work, and rarely "loosen" their breasts.