The principle of "three early" refers to early detection, early diagnosis, and early treatment, which is a key strategy to improve the cure rate of cancer and improve patient prognosis. With the continuous improvement of tumor screening methods, more and more tumors can be detected at an early stage. One examination can screen out all cancer risks, "" In clinical practice, only a drop of blood is needed to screen for cancer, "" X-ray examination can 'detect' early lung cancer, "etc. Currently, there are many erroneous claims about tumor screening circulating on the Internet, and reporters interviewed relevant experts about this. Statement 1: One examination can screen out all cancer risks. Expert response: A comprehensive understanding of cancer risks requires the use of multiple screening methods. There is a saying online that all cancer risks can be screened out through one comprehensive examination. Regarding this, Wang Huaqing, a professor at Nankai University School of Medicine and director of the Cancer Diagnosis and Treatment Center at Tianjin People's Hospital, said, "Cancer is not a single disease, but a collective term for various types of malignant tumors, involving multiple organs and tissues in the human body." Each type of cancer has specific screening methods and biomarkers, which means that no single examination can cover all types of cancer. For example, Wang Huaqing said that screening for breast cancer usually uses mammography (molybdenum target); The screening for colorectal cancer involves colonoscopy or fecal occult blood test; Prostate cancer screening may involve prostate-specific antigen testing; The screening of lung cancer relies on low-dose chest CT scans, etc. The screening tools and strategies for each type of cancer are designed based on their biological characteristics and early manifestations, "said Wang Huaqing. A comprehensive understanding of a person's cancer risk requires the use of multiple screening methods, including but not limited to tumor marker testing, imaging examinations, endoscopic examinations, etc. The examinations should be customized based on specific factors such as age, gender, family history, and lifestyle. Wang Huaqing suggests that the correct approach is for doctors to regularly develop personalized screening plans for individual cancer risk factors, in order to achieve early detection and treatment of tumors. Statement 2: In clinical practice, only one drop of blood is needed to screen for cancer. Expert response: Currently, there are no mature related products applied in some movies, and doctors can diagnose various diseases including cancer with just one drop of blood. With the development of medical technology, it is said that the technique of "blood drop testing for cancer" has now been applied in clinical practice. Wang Huaqing said that the process of cancer screening and diagnosis is complex. At present, it is difficult to screen for cancer based solely on a drop of blood in clinical practice. Liquid biopsy is a non-invasive cancer detection method. It detects the presence of cancer by analyzing biomarkers in the blood, such as circulating tumor DNA (ctDNA), circulating tumor cells, or extracellular vesicles. However, accurately screening for cancer from a drop of blood is not an easy task, "Wang Huaqing believes. Firstly, the concentration of ctDNA released by tumors is extremely low and mixed with a large amount of normal DNA, making detection extremely difficult; Secondly, even if ctDNA abnormalities are detected, it does not necessarily mean that cancer exists, and such abnormalities may also be caused by other factors; Finally, the number and types of biomarkers released by different cancers vary greatly, and a single detection method is difficult to cover all types of cancer. It is gratifying that significant progress has been made in liquid biopsy technology in recent years. The research team has been able to detect extremely small amounts of ctDNA, which carry genetic variations unique to tumors. Through high-precision sequencing technology, scientists are striving to improve the sensitivity and specificity of detection, aiming to accurately identify cancer signals in the early stages when they are weak. With the continuous maturity of technology, liquid biopsy is expected to become a powerful tool for cancer screening, "said Wang Huaqing. Statement 3: X-ray examination can "detect" early lung cancer. Expert response: Tumors need to grow to a certain extent before they can appear on X-ray images in early screening of lung cancer, and X-ray examination is often mentioned. It is said that X-rays can effectively capture the traces of lung cancer in the early stages. Wang Huaqing said that X-ray examination has low sensitivity and specificity for early screening of lung cancer, especially for tumors with a diameter less than 1 centimeter, with a detection rate of less than 15%. Tumors can only appear on X-ray images when they have grown to a certain extent. At this point, lung cancer often has progressed to the middle and late stages, making treatment significantly more difficult and the prognosis significantly worse. X-ray examination uses X-rays to penetrate the human body and produce two-dimensional images, helping doctors observe the condition of bones and certain soft tissues. However, X-ray imaging is affected by the overlap of human tissue, and smaller lung cancer lesions are easily obscured by surrounding normal tissue structures. In addition, early lung cancer may appear as irregular or blurry shadows, making it difficult for doctors to distinguish early lung cancer from benign lesions or normal variations through X-ray imaging. In addition, the resolution of X-rays is limited, and their diagnostic value is greatly reduced for areas deep in the lungs or with complex structures. Compared with X-ray examination, low-dose spiral CT examination is the first choice for modern lung cancer screening, especially for high-risk populations such as long-term smokers and individuals with a family history of lung cancer Wang Huaqing explained that CT scans can provide three-dimensional images of cross-sections, which can more clearly display lung details and have a higher detection rate even for small nodules. This makes it a safe and efficient early lung cancer screening tool. (New Society)