Cancer can occur regardless of age groups; children, young children, young and middle-aged people, and the elderly can all develop cancer, and different age groups have different cancer incidence spectrums. For example, tumors of the blood system, mainly leukemia, can occur in infants or children. Young and middle-aged people can also develop lung cancer, breast cancer, colorectal cancer or acute leukemia. Older people mainly develop various solid tumors, such as liver cancer, lung cancer or pancreatic cancer, breast cancer, etc. Therefore, malignant tumors or cancers can also occur at the age of 20, and the same clinical attention needs to be paid to certain cancer symptoms. For example, coughing, coughing and blood in sputum should be beware of lung cancer, and lumps in the liver should be beware of the possibility of liver cancer, and regular medical checkups are needed for timely and early detection of cancer.