With the improvement of living standards, people are increasingly aware that “keeping exercise, balanced diet and regular medical check-ups” are the three major measures to protect health. However, many people have questions about medical checkups: What are the mandatory checkups? What are the items that can help to detect the signs of cancer at an early stage? Tumor markers Blood tests are very common, but the blood test mentioned here is different from the usual “blood test”, but focuses on tumor markers. Tumor markers are substances that may be detected when malignant tumor cells are present. It may be synthesized or released directly by malignant tumor cells or produced by the body in response to tumor stimulation. Tumor markers can reflect the occurrence and development of tumors, even in the early stage of tumor development when they are not visible to the naked eye or imaging. For example, alpha-fetoprotein (AFP), a protein synthesized in human embryo, has become almost undetectable in blood after birth, while 87% of primary liver cancer tissues are able to re-synthesize AFP, making the level of this substance in blood rise again, thus AFP is a common test for diagnosing primary liver cancer. Anal finger diagnosis and fecal occult blood test If we have polyps or even tumors in the intestine, the subjective sensation is not very obvious, some patients may have some changes in bowel habits, and some patients show blood in the stool. In general, the symptoms are so atypical that many people overlook the existence of the lesion and delay the disease. In fact, most cancers of the intestinal tract are found in the rectum, and 70% of rectal cancers occur not far from the anus. Through anal fingering, doctors can directly touch and determine whether there are lesions in the rectum 7-10 cm from the anus; through fecal occult blood test, they can observe blood in the stool that cannot be seen by the naked eye with a microscope, which can provide important warning signals for doctors. Gastroscopy and colonoscopy Gastroscopy and colonoscopy, said to be a way to enter through the body’s own natural channels (mouth or anus) and thus observe the gastrointestinal tract, have the characteristics of being non-invasive and less invasive. Under endoscopy, doctors can visualize the state of the mucosa of the gastrointestinal tract, determine the presence of lesions or directly remove tissue samples for pathological examination, or even perform microscopic surgery to directly remove lesions. In fact, endoscopy is the best way to detect stomach and intestinal cancers early. If the stool occult blood test is positive, it is even more necessary to check the colonoscopy to determine the location of bleeding and the nature of lesions. Chest X-ray and ultrasound Lung cancer has always been a killer that endangers human health, ranking first in the incidence and mortality rate of male cancer worldwide for years. A century ago, mankind did not have a very effective way to prevent lung cancer and other organ tumors. History changed with the birth of X-rays and ultrasound, which applied rays and sound waves respectively, allowing doctors to probe the internal structures of the human body without opening an incision. Physical examination of chest X-ray and ultrasound can reveal the presence of mass lesions in most organs of the body such as lung, thyroid, bile, spleen, kidney and pelvis, which are likely to be tumors. It should be especially noted that the clarity of chest X-ray and ultrasound does not fully meet the requirements for early cancer screening, but clearer CT and MRI examinations predict higher costs as well as higher radiation risks. Whether CT or MRI examinations are necessary should be considered in consultation with a doctor, based on factors such as smoking, occupational exposure, and underlying diseases. Cervical smear and mammogram For women, breast cancer and cervical cancer have long been at the top of the list of cancer incidence. Cervical smear collects cells from the mouth of the cervix through a facial swab and can directly analyze whether there is atypical hyperplasia or even cancer in the cervix. Mammogram is good for detecting microscopic lesions deep in the breast. It can show the location, shape, size, edge and calcification of lesions, which can help doctors to initially determine the degree of benign and malignant lesions, and can be a good helper for early diagnosis of breast cancer.