The chance of malignant lesions in various tissues and organs has increased significantly in recent years due to the influence of living environment, diet and work pressure, etc. Some organizations organize annual physical examination to detect early cancer in advance, but physical examination is not equal to early cancer prevention, so please don’t be misled into the misunderstanding. PET-CT is not a “universal key” to detect cancer. “PET-CT can detect latent tumor by scanning the whole body? Don’t be too optimistic! The principle of PET-CT is that because cancer cells divide more vigorously than normal cells, the demand for glucose is three to eight times higher than normal cells, so during the examination, radioactive FDG (fluorodeoxyglucose) is injected intravenously into the examinee and flows throughout the body. Gamma rays are emitted from the FDG, and the cancer is detected as the FDG accumulates in large numbers at the cancer cells. Generally speaking, PET examinations can detect cancers as large as 1 cm in size, but it also has a fatal flaw: some cancer cells are unable to aggregate FDG, and normal cells that have aggregated FDG may overlap with cancer cells, and in both cases, PET examinations often yield erroneous results. It is unreasonable to rely solely on one diagnostic method for early cancer screening, and we should give full play to the advantages of various examinations, such as diagnostic imaging, biopsy and blood test, to make a comprehensive diagnosis in order to avoid “false negatives” and “false positives”. The only way to avoid “false negatives” and “false positives” is to make comprehensive diagnoses by making full use of the advantages of various examinations, such as imaging, biopsy and blood tests. For example, low-dose spiral CT of chest should be preferred for early screening of lung cancer; PET examination is mostly used for systemic screening of metastasis after lung cancer is diagnosed or to confirm the effect of cancer treatment; ultrasound examination can detect thyroid, liver, gallbladder, pelvis and prostate in detail; chest X-ray can detect lung, esophagus and mediastinum lesions in time; CT is suitable for brain, liver, gallbladder and pelvis. Check …… Myth 2: Higher tumor markers means higher possibility of cancer? Many patients often rely on the results of tumor marker test to determine their risk of cancer, and panic when they see a high tumor marker value. In fact, tumor markers are mainly used for the treatment effect and post-operative observation of middle and late stage cancer. Tumor marker values alone cannot accurately determine the existence of early stage cancer, its deterioration and recovery. If the sensitivity is low, cancer may not be detected or patients with cancer may be diagnosed as “normal”. If the sensitivity is low, it may not detect cancer or diagnose a patient with cancer as “normal”, and if the specificity is low, it may be a “false positive”, which means a healthy person will be misdiagnosed as cancer, causing panic. Therefore, several tumor markers are usually used in clinical practice to diagnose possible tumors by testing them simultaneously. There is not a clear correspondence between tumor markers and cancer. For example, tumor marker CEA, for colorectal cancer, breast cancer, gastric cancer, pancreatic cancer, etc., will show high values and exhibit lower organ specificity. To clarify the organ where the cancer is hidden, a secondary examination is needed. On the other hand, tumor markers can be “good and bad”, for example, tumor marker PSA only shows high value for prostate, although it has high organ specificity, it can also misrepresent the disease, for example, benign prostate diseases such as prostatitis and prostate enlargement, and elderly people may also get high value in PSA test. It is also important to note that tumor markers rarely show high values in the early stages of cancer. There are often patients who do not have high tumor marker values because their tumors are not large enough. Myth 3: Regular physical examination is not necessary to do early cancer screening? People often confuse the nature of health checkup and early cancer screening, health checkup cannot replace early cancer screening. Early cancer screening is a medical examination for healthy people who have no symptoms. In addition to screening for early cancer, it will also check and evaluate some functional changes and diseases that increase the probability of developing cancer. Cancer screening is often selected according to different conditions at different ages, and the setting of the screening program is more individualized. For example, for those with a family history of breast cancer, women over 40 years old should choose breast ultrasound and mammogram. Those who have a family history of nasopharyngeal, breast or ovarian cancer, long-term smokers, those with hepatitis B or major and minor triplets, those with gastric ulcer and chronic gastritis, those with lobular hyperplasia of the breast and those with HPV high-risk subtypes should undergo regular cancer checkups at hospitals. Talking about new methods: Beware of “over-treatment”. In recent years, as cancer treatment methods continue to develop, there are more and more new methods such as minimally invasive treatment, biological treatment and molecular targeted therapy, and many people have high hopes for them. “Cancer treatment must be controlled by ‘degree’!” It is good to have more cancer treatment methods, but not every cancer patient is suitable for new therapies. “It should be different from person to person, especially in the use of molecular targeted drugs, patients must do genetic testing first and not use drugs blindly.” When a tumor comes, the body will send you distress signals, it depends on whether people are paralyzed to let it go or sensitive to catch the signals. Usually, we should pay attention to the detailed changes of the body. If there is a new phenomenon or change of body pattern, such as sudden tinnitus, abnormal stool, weakness, anemia, etc., we should pay attention to it. Talking about Chinese medicine: Chinese medicine only plays a supplementary role in fighting cancer In China, Chinese medicine is an inescapable topic when talking about cancer treatment. Chinese medicine treatment is a kind of treatment with great individual differences. For the same disease, different patients’ physique, age, gender, and even different physicians will lead to different medication, so it is difficult to conduct large-scale clinical experiments for verification. A large amount of clinical experience shows that many Chinese herbal medicines can indeed be used for adjuvant treatment of cancer and can be very effective in relieving patients’ injuries and pains, alleviating complication symptoms, etc. However, Chinese herbal medicine is only used for adjuvant treatment of some cancers, and not as the mainstay of the fight against cancer.” Cancer focuses on prevention. Cancer prevention must emphasize the importance of a healthy lifestyle. No smoking, less drinking, good diet structure, exercise, ventilation and airy living environment can reduce the incidence of cancer to a certain extent and form a “small cancer prevention environment”.