人为什么会得癌症,至今仍没有明确的答案,我们已经注意到了诸如抽烟、空气污染、不良生活习惯等许多较为肯定的致癌因素,但是并不是所有抽20年以上香烟的人都患肺癌;人们生活在同样被污染的空气中,患癌症的还是少数;一个家庭里人人都吃酸菜,可能只有一个人得了食管癌等等。这说明,除了外部因素外,人体内部环境还起决定性作用。这一起决定性作用的就是人的免疫系统。免 Why do people get cancer? There is still no clear answer. We have noticed many positive factors such as smoking, air pollution, and bad habits. However, not all people who smoke cigarettes for more than 20 years suffer from lung cancer. Living in the same polluted air, the cancer is still rare; in a family where everyone eats sauerkraut, only one person may have esophageal cancer and so on. This shows that in addition to external factors, the human internal environment also plays a decisive role. This is a decisive role in the human immune system. Free