The World Health Organization has put forward “eight warning signs” as signals for early detection of tumors: 1. Hard knots or lumps in any part of the body, such as hard knots found in breast, skin and tongue, and abdominal lumps, especially those with irregular shape and not smooth, and those that may gradually increase in size, which should be paid special attention to (e.g., breast cancer, tongue cancer, and skin cancer, Liver cancer may have the above symptoms; 2. Obvious changes in warts or moles (e.g. malignant melanoma); 3. Persistent digestive abnormalities, which may be accompanied by progressive weight loss and poor appetite (e.g. stomach cancer, liver cancer); 4. Persistent hoarseness (e.g. lung cancer, laryngeal cancer), dry cough (e.g. lung cancer), and difficulty in swallowing (e.g. esophageal cancer, gastric cancer, pharyngeal cancer), and burning, pain, and foreign body sensation at the back of the sternum after eating, which may progressively aggravate (e.g. esophageal cancer, gastric cancer, pharyngeal cancer). (e.g. esophageal cancer, stomach cancer, pharyngeal cancer); 5. Unusual menstruation, hemorrhage, bleeding outside the menstrual period, abnormal and increased vaginal secretion, especially in middle-aged and old women (e.g. ovarian cancer, cervical cancer, endometrial cancer); 6. Bleeding from nose, ear, bladder or intestines for unknown reasons (e.g. nasopharyngeal cancer, bladder cancer, kidney cancer, prostate cancer, colorectal cancer); 7. Wounds that persistently don’t heal, especially wounds occurring on their own without traumas; swelling that persistently doesn’t heal, especially wounds occurring on their own without traumas. Unexplained weight loss: recent weight loss is a common symptom of most tumor patients (e.g. liver cancer, pancreatic cancer, lung cancer, esophageal cancer, stomach cancer).