Early signals of cancer usually do not reflect on the nails. Early stage of cancer may have systemic symptoms such as fatigue, fever, and other specific manifestations depending on the site of onset. Cancer is a malignant disease caused by heredity, gene mutation and other factors. Early stage of the disease often has no specific clinical manifestations, and there may be systemic symptoms such as fever, fatigue and unexplained emaciation. In addition, according to the different parts of the cancer, more specific clinical manifestations may appear. For example, lung cancer patients may have symptoms such as cough, sputum, hemoptysis and chest pain; stomach cancer may have symptoms such as loss of appetite, black stool, belching (burping); liver cancer may have symptoms such as jaundice and pain in liver area. Therefore, when discomfort occurs, one should go to the hospital in time.