Expert advice of China Anti-Cancer Association： Kill early cancer in the cradle.

　　April 15th to 21st is the 25th National Cancer Prevention Publicity Week, and this year’s publicity theme is "Scientific Cancer Prevention First".

　　Cancer, also known as malignant tumor, is a complex disease caused by social and environmental factors and genetic factors. The genetic changes that can lead to cancer may be inherited from parents, may also be caused by abnormal cell division or exposure to special environment after birth, and may also be carcinogenic environmental exposure, including some special substances, such as harmful chemicals and rays formed by tobacco burning.

　　At present, malignant tumor accounts for the first cause of death among urban residents in China. From 2000 to 2014, the onset age of cancer in China is moving forward every year, with an overall advance of about two years. Through the cooperation of surgery, internal medicine, radiotherapy and other multidisciplinary departments for many years, human beings have mastered the tools for early detection of cancer such as CT, ultrasound, tumor markers, and at the same time have many effective cancer treatment methods such as surgery, chemotherapy and radiotherapy.

　　Can cancer be prevented?

　　In fact, the formation of cancer is very slow, and it takes about 20 to 30 years for the human body to develop into cancer after long-term exposure to carcinogenic environment.

　　During this period, we have to go through many steps, such as cell transformation, precancerous lesions, carcinoma in situ, and gaining the ability of invasion and metastasis. In the previous twenty or thirty years, we had plenty of time to find and eliminate cancer. Therefore, early screening and diagnosis of cancer is particularly important.

　　"Gene mutation" and "immune escape" are two key factors in the formation of cancer. Gene mutation is a "restless" cell, and it will not stop when it stops proliferation. Immune escape is a "restless" cell that escapes the surveillance and attack of the immune system through various methods.

　　Can cancer be prevented? The answer is that some cancers are completely preventable.

　　In 2011, the World Health Organization proposed that one-third of cancers could be completely prevented; One third of cancers can be cured by early detection; One-third of cancers can use existing medical measures to prolong life, relieve pain and improve quality of life. This ratio means that, optimistically, cancer can not be fatal, pessimistically, some tumors can not be predicted and escaped.

　　Tumor prevention, the ideal state is to find and intervene in the precancerous lesions, so as not to let the precancerous lesions develop into cancer, such as lung cancer, which we are familiar with. If we intervene in time in the early stage of disease development, more than 90% can be cured.

　　The focus of cancer prevention is "etiological prevention"

　　The prevention of cancer is divided into three levels. For most of us, the emphasis should be on the primary prevention, that is, the "etiological prevention" of cancer, which is what we usually call "prevention of disease". Why pay attention to this level of prevention? Because of its long time, many opportunities, good effect and low cost.

　　Cancer prevention should "do something". Starting with improving the internal environment of our bodies, that is, enhancing our "immunity". Vaccination can improve the body’s immunity to specific viruses. Although there is no such thing as cancer virus, some viruses can indeed cause cancer. For example, HPV vaccine can prevent cervical cancer and hepatitis B vaccine can reduce the incidence of liver cancer.

　　In addition, you can keep your immune system in good condition by controlling your weight, exercising moderately and keeping your mood comfortable.

　　To prevent cancer, we must "do something." To do something wrong is to avoid carcinogenic factors in life. This includes external factors such as physics, chemistry and biology, as well as some internal genetic factors. According to the list of carcinogens published by the World Health Organization, a total of 116 substances are classified as a class of carcinogens, which are certain to cause cancer, including tobacco, alcohol, formaldehyde and so on. Reducing exposure to carcinogenic factors in daily life is an important step in cancer prevention.

　　The public’s awareness of smog prevention has weakened.

　　Paranoid, introverted, unwilling to communicate with friends, once family, emotion, work and other things go wrong, the psychological pollution index is higher, which belongs to the "cancer personality" that is often said.

　　Professor Zhi Xiuyi, director of the Propaganda Department of Popular Science of China Anti-Cancer Association and chief expert of thoracic surgery in xuanwu hospital, Beijing, said: "Nearly half of the lung cancer patients admitted in clinic are related to long-term depression, depression and emotional shock."

　　Mental factors can not directly cause cancer, but they often affect and reduce the immunity of the body with a chronic and persistent stimulus. It causes the imbalance of autonomic nervous function and endocrine function, makes cancer cells break through the defense of the body’s immune system, and then forms cancer.

　　According to the report of the World Health Organization, healthy exercise, diet and sleep can prevent 30%~50% of cancer, and many deaths caused by cancer can be avoided.

　　Feng Li, director of Chinese Medicine Department of Cancer Hospital of China Academy of Medical Sciences, said that staying up late and getting angry are a risk factor for cancer, but they are not the main key factors. Because the key factor of tumor occurrence is mainly internal factors.

　　In addition to keeping your mouth shut and keeping your legs open, you should pay attention to eating more grains, vegetables, fruits and beans to prevent cancer; Eat less red meat and processed meat; Eat less salt; Drink less alcohol; Do not smoke; Stay up late less.

　　In addition, "anti-cancer screening" can make "early cancer" strangle in the cradle ",and women ≥ Cervical cancer screening should be done at the age of 20, and it is best for women over 40 to do breast cancer screening, including breast ultrasound and mammography. Professor Zhi Xiuyi reminded that people over 40 years old had better do screening for esophageal and gastrointestinal tumors, mainly painless gastrointestinal endoscopy. When you are over 50 years old, do colorectal cancer screening, including fecal occult blood test and colonoscopy. Over 50 years old and smoking ≥ 20 packs/year, low-dose spiral CT is recommended. (High-risk groups can advance their age to 40)

　　In recent two years, people’s awareness of smog prevention has gradually weakened, and the number of people wearing masks on the streets in foggy days has decreased significantly. Many people seem to be used to it, and it doesn’t matter to run on the streets in foggy days.

　　Professor Zhi Xiuyi appealed to the public to pay attention to the health effects of inhalable particulate matter PM2.5 and smog weather. Minimize going out in foggy weather; If you have to go out, you should also try to reduce your stay outside, wear a protective mask when you go out, and reduce the intake of PM2.5