Most of the cancer patients may have fatigue and tiredness symptoms when they are in the middle or late stage, and they need to go to the hospital for examination in time. Cancer is a malignant disease caused by heredity, gene mutation, environment and other factors. Due to the occurrence and development of tumors, which may cause huge energy consumption, some patients may suffer from anemia, electrolyte disorders, resulting in clinical manifestations such as fatigue and tiredness, which may be accompanied by fever and unexplained emaciation, etc. In addition, different types of cancer may have relatively specific symptoms. In addition, different types of cancers may have specific symptoms, such as lung cancer with cough, sputum, hemoptysis, etc.; gastric cancer with vague pain in upper abdomen, loss of appetite, nausea and vomiting, etc.; colon cancer often accompanied by changes in stool habit and character, abdominal pain, etc. In case of unexplained fatigue and other discomforts, one should be vigilant, consult the doctor in time, complete the examination, make a clear diagnosis and standardize the treatment.