1.Definition and pathogenesis of cancer
In medicine, cancer refers to a malignant tumor originating from epithelial tissue. It is the second largest disease in terms of morbidity and mortality after cardiovascular disease. The cause of cancer is the mutation of cells. Unlike normal cells, cancer cells have the characteristics of infinite value-added (uncontrolled division), transformability and easy metastasis, which can destroy normal cells.
According to the "Global Cancer Statistics 2018" published by the American Cancer Society, in 2018, there were 18 million cancer cases and 9.6 million deaths worldwide. Among them, the incidence of cancer in China was 3.804 million and the mortality rate was 2.296 million. First, China accounts for 21 of the 100 new patients worldwide. That is to say, more than 10,000 people are diagnosed with cancer every day in China, and an average of 7 people get cancer every minute.

The highest incidence of new cancers worldwide is: lung cancer (11.6%), breast cancer (11.6%), colorectal cancer (10.2%), prostate cancer (7.1%), gastric cancer (5.7%); the highest mortality rate in the world The cancers were: lung cancer (18.4%), colorectal cancer (9.2%), gastric cancer (8.2%), liver cancer (8.2%), and breast cancer (6.6%). 

2. Factors Affecting Cancer
Environmental pollution, smoking and drinking, radiation exposure, viral infections, lack of exercise, improper diet, lifestyle (bad habits such as smoking and drinking, lack of exercise, obesity or being overweight, staying up late), psychological factors (long-term mental depression, negative emotions) , Substance abuse (especially long-term heavy use), genetic factors, etc.

3. The absence of cancer does not mean that the probability of cancer is zero
In fact, there are "cancer cells" in every human body. When more than 10 billion cells are grown during the daily metabolism, DNA replication will inevitably make mistakes, leading to gene mutations and pre-cancer cells are likely to appear in mutated cells. . Although every human body has the production of pre-cancer cells, but it has developed into a small number of malignant tumors. Most abnormal cells will be repaired, corrected or eliminated by the body's immune system to ensure the dynamic balance of the body's various cell functions.

4. Why are there cancer cells but not cancer?

 Thank you so much for our body's immune system. Human immunity mainly depends on white blood cells. White blood cells are also called white blood cells. Its function is to protect the body from pathogens (bacteria and viruses), cancer cells, and foreign bodies. It is the guardian of the human body. The mutated cells are "bad molecules". If they are not eliminated, they may develop into the enemies considered to be the enemy-cancer cells. Under normal circumstances, the body's immune system is constantly monitoring and eliminating these abnormal molecules.

 The main role of this process is:

The appearance of cancer cells (abnormal cells) → monitoring and function of the body's immune system → T cells take the initiative to contact and stick to the cancer cells, using its enzyme to change the permeability of the cancer cell membrane, resulting in cancer cells Internal potassium ions flow out in large quantities, and sodium, calcium ions and water are injected in large quantities. In this way, cancer cells will lose the balance of permeation and be destroyed; B cells also participate in the anti-cancer campaign, which can synthesize intentional antibodies ——Immunoglobulins are distributed throughout the body fluids to form an immune battlefield and destroy and kill cancer cells.

5. Why do cancer cells get killed by the system, but they still get cancer?
 When the body's immunity declines, causing the cancer cells to not be eliminated in time and mass reproduction, the body's immune system will be destroyed. Cancer cells multiply uncontrollably, causing great harm to the human body.

How to Prevent Cancer (Medical Examination and Early Cancer Treatment)

For cancer, the best way to prevent and cure is to conduct a precise rather than routine physical examination to prevent and treat early.

Cancer cells are small and have high requirements for the precision of the detection equipment. The general routine physical examination is to check whether there is any cancer. Japan's physical examination is world-famous, especially in anti-cancer screening. It can find and detect a variety of known early and early cancers, and maintains a record of leading anti-cancer examinations in the world. It can find most possible early cancers at the millimeter and micrometer level below 10mm. China can only detect centimeter level. In addition, Japan not only has excellent oncologists, but also has the world's top anti-cancer technology and equipment. In Japan, 80% of cancers are found in the early stages, and 80% of them can be cured. It can be said that Japan's cancer prevention and cure rate is the world's leading! Experts remind that it is best to do cancer screening once a year, which will also help you to have a deeper understanding of your physical condition.

7. Tips for Preventing Cancer in Everyday Life

Cancer prevention recommendations:

1. Reasonable diet. Choose foods with more antioxidants and strong anti-cancer effects. Such as dark fruits and vegetables rich in vitamin A-carrots, broccoli, spinach, red sweet potatoes, etc .; foods rich in vitamin C-sea buckthorn, kiwi, and jujube; foods rich in vitamin E-nuts, beans, etc. ; Foods rich in selenium-sea cucumbers, oysters, clams, etc. Be careful not to consume too much salt, you need to eat more fruits, and do not overeating.

2. Change bad lifestyle. Quit smoking, drink less alcohol, reduce sun exposure, eat less junk food, etc. Improve cooking methods and avoid burning food.

3. Maintain the ideal weight and regular life, exercise reasonably every day.

It is believed that with the rapid development of medical technology and the sharing of high-quality medical care worldwide, the incidence and mortality of cancer will be controlled. I hope everyone can stay away from cancer and have a healthy body.