Usually, there are no obvious symptoms in the early stage of cancer, and there are differences in the manifestations of various cancers, so there are no 20 clinical cancer signals, but when the body shows obvious abnormal manifestations, it indicates the appearance of lesions or even cancer, the main manifestations are as follows: 1. The temperature is lower than the fever caused by bacterial infection; 2. Lack of energy: cancer is a consuming disease and the growth and spread of cancer cells will consume the body’s energy, so the patient is easily fatigued and weak; 3. Lumps: thyroid cancer, breast cancer or skin cancer may appear lumps in the early stage, while cancer in the chest or abdominal cavity may develop to the middle or late stage before the lumps become visible; 4. There is a certain correlation between the pain site and the lesion site, but it does not correspond exactly; 5. Weight loss: cancerous tissues consume nutrients of the body, so patients may lose weight to different degrees, and generally the weight loss is faster; 6. For cancer of the urinary tract, there are manifestations such as difficulty in urination, blood in urine, frequent urination and urgent urination; for cancer of the skin, there are local redundancy, pigmentation or subcutaneous bleeding, etc. All these symptoms may suggest cancer, but they are not unique manifestations of cancer and need to be differentiated.