The saying that six signs do not mean that you will not get cancer is false, and there are often no specific signs in the early stage of cancer. You should be alerted by some clinical signs to determine whether you have cancer or not. Cancer is a malignant disease caused by hereditary and environmental factors. Early stage of cancer often has no specific manifestations, and there may be symptoms such as fatigue, fever, and unexplained emaciation. In addition, the symptoms may vary according to the different parts of the disease. For example, lung cancer patients may have chest pain, cough, sputum, hemoptysis, etc.; stomach cancer patients may have epigastric pain, loss of appetite, nausea and vomiting, etc.; colon cancer patients may have abdominal pain, change of bowel habits, etc. Sometimes, patients may already suffer from cancer, but due to the symptoms are not obvious, they will be neglected, which eventually leads to poor prognosis. Therefore, regular medical checkups should be conducted in daily life, so as to strive for early detection, early diagnosis and early treatment, and obtain a better prognosis.