Should early cancer screening be done? does it worth?
2020-08-12
On the CT scan of the chest that Ms. Peng had just completed, there was an unclear boundary, about 2 cm in size, and a "ground glass"-like shadow that attracted the attention of imaging departments and surgeons.
How to judge the nature of this "ground glass nodule" has become a crucial step, which is related to whether she can seize the opportunity of Ms. Peng's survival time. This is not alarmist. There is Professor Zhang, a film reader who is known as the "Eye of the East". In 10 years, after reading more than 500,000 CT films for 160,000 patients, the professor has accumulated extremely rich experience. The "Zhang Guozhen Difficult CT Scanning and Pulmonary Micronodule Diagnosis and Treatment Center" led by him is in a leading position in China for the screening and treatment of micro lung cancer. The professor said that with the popularization of physical examinations and the advancement of diagnostic equipment, the discovery of tiny nodules of unknown cause in lung imaging examinations is no longer an isolated phenomenon. Tiny nodules may mean various benign lesions in the lungs, but they may also be signs of cancer. His job is to judge "right and wrong" within a few minutes, and the experience of exploring success can be summed up as "early".
The earlier the discovery, the better the effect. This principle of diagnosis and treatment is particularly prominent in the field of lung cancer.
The postoperative pathological examination also confirmed the team’s cognition that Ms. Peng belongs to stage 0 lung cancer. Due to timely diagnosis and treatment, radiotherapy and chemotherapy are not required after surgery. After a month of rest, Ms. Peng resumed her normal life.
Health checkup ≠ early cancer screening
Ms. Peng was deeply grateful for this unpredictable experience, but also very confused. She had just had her annual physical examination six months ago. Had it not been for an opportunity for early cancer screening by accident, she would never have discovered this "ground glass shadow" and would have missed the opportunity to discover and treat early lung cancer.
"Early cancer screening is different from ordinary health checkups. Health checkups are routine tests for chronic diseases to grasp general conditions such as heart, liver, kidney function, blood sugar, blood lipids, and blood pressure. Early cancer screening is for asymptomatic Of healthy people.” said Ms. Zhang, Medical Director of Early Cancer Screening Center, Xiekang Changrong Hospital Management (Beijing) Co., Ltd. As a medical service organization specializing in standardized early cancer screening and physical examination, with Kang Changrong and Shanghai International Medical Center, through the introduction of international advanced early cancer screening systems, standards, and international experts with many years of early cancer screening experience, the establishment of A mature early cancer screening system.
The Centers for Disease Control and Prevention (CDC) of the United States defines cancer screening as "checking the body for cancer before symptoms occur", that is, discovering the tumor while it is still in its infancy. Many cancers, such as lung cancer, stomach cancer, colorectal cancer, etc., have almost no obvious symptoms in the early stages of the disease, and it is difficult for patients to actively feel the changes in the body. According to data from the annual tumor reports of various countries, the average cure rate of early cancer is more than 95%. The comparison of the early and late cure rates of the 5 major cancers in the United States and Japan found that the cure rates of gastric cancer, colorectal cancer, breast cancer, and cervical cancer can reach more than 90%, and the cure rate of breast cancer is as high as 98%. , Stage II is more than 80%, stage III is less than 40%, and stage IV is less than 10%. The advanced cure rate of gastric cancer in Japan is only 3%. In other words, through screening to achieve early detection and early treatment of cancer, the survival probability of cancer patients is very high.
Compared with developed countries such as Japan and the United States, the gap in cancer incidence, cancer treatment technology, and cure rate is not large, but there is a significant gap in survival rate. The key reason is the early detection and screening of cancer. Take Ms. Peng's lung cancer as an example. Its morbidity and mortality rate have always been the first among malignant tumors in my country, and most of the patients are already in advanced stages when they are discovered. The later the lung cancer is discovered, the later the treatment, the worse the effect. The latest statistics show that the five-year survival rate of stage 0 lung cancer, that is, carcinoma in situ, is almost 100%, early stage lung cancer is about 70%, mid-stage lung cancer is also around 50%, and advanced stage patients are only 20%.
“Early cancer screening is recognized as the most effective way to reduce the mortality rate of cancer.” Mr. Ma, general manager of Xiekang Changrong Hospital Management (Beijing) Co., Ltd., “Early cancer screening is a way for healthy people to detect malignant tumors. And intercept the early method. However, most people do not realize the importance of early cancer screening, and most institutions do not have the ability to detect cancer early, so many hospitals’ oncology departments are overcrowded."
Ms. Peng's ability to pass lung cancer this time is inseparable from a convenient screening method-low-dose spiral CT of the chest, which is currently internationally recognized as the most reliable examination method for early lung cancer detection. Zhang Ling suggested that people who are over 50 years old, have a history of smoking or family history, or have underlying lung diseases are all high-risk groups, and low-dose spiral CT screening for lungs is recommended.
Gene predicts the future
Early detection, early diagnosis, and early treatment are the keys to reducing cancer deaths. So if everyone has the awareness of cancer screening and intercepts cancer cells in their budding state, won't the survival rate of cancer patients be improved, and the ideal "change of fate" can be achieved?
The reality is far from simple. At present, there is no strict screening procedure for early cancer in my country. The main cancer screening methods currently used can be roughly divided into imaging examinations (such as ultrasound, CT, X-ray, MRI, etc.), laboratory sampling tests (checking blood, stool or other body fluids, looking for tumor markers) and routine physical fitness Examination (such as touching to find breast and testicular cancer lumps), etc. PET-CT and tumor markers, which we are more familiar with, are more clinically used to observe the effect of tumor treatment and metastasis, and cannot be used as the gold standard for early cancer screening.
"For example, the tumor marker for liver cancer is AFP, lung cancer is CEA, ovarian cancer is CA125, breast cancer is CA153, and pancreatic cancer is CA199. These tumor markers can reflect the occurrence and development of tumors to a certain extent. It is helpful to monitor the effect of tumor treatment and prognosis." Ms. Zhang said.
In response to the "a drop of blood that can detect cancer" that was circulated by the media some time ago, Ma Jianpeng pointed out that "a drop of blood to detect cancer" can indeed provide indications and judgments for human cancer, but it is easy to appear due to individual differences and living habits. The possibility of false negative and false positive, even if it is really positive, it cannot be judged that it is 100% suffering from malignant tumors and cannot accurately locate the tumor location. The international gold label still needs to be diagnosed and judged by imaging and pathology, so this examination has no imagination It’s so magical and can only be used as an auxiliary means of comprehensive judgment, nothing more. "But I believe that with the advancement of medical technology and the development of precision medicine, I very much look forward to the realization of this dream. Because of its simple and convenient operation, it will surely replace the "detailed, standardized, deep" and relatively cumbersome that we currently use. Early cancer screening can be more popular among the public, increase the rate of early cancer detection, and reduce the cancer death rate of the Chinese people. This is also the goal of all of our health-caring people."
In recent years, the concept of "genetic testing" has become more and more popular, and because it has cracked the personal genetic code to a certain extent, it has been given the mysterious function of "foreseeing the future". In 2013, Angelina Jolie learned through genetic testing that she was carrying a BRCA 1 mutation that increases the risk of breast and ovarian cancer. Among her immediate family members, her mother, aunt, and sister have all died of ovarian cancer and breast cancer. Therefore, when she learned that she had a defective gene and was more likely to develop breast cancer, she took preventive mastectomy.
At the beginning of August 2016, Liu Di bound a public account. With a fun mentality of the picture, she spent 999 yuan for a genetic test-it sounds very "tall", but the process is very simple, she just confronted The sampling box spit out, sealed it and mailed it to the designated address, and soon received a detailed report comparable to the decryption of a human body. "46.16% of Northern Han ethnicity", "84.53% Chinese nation, 15.45 Koreans", "Maternal ancestor M11b11, originated from 60,000 years ago" "Exercise has a slower effect on weight loss" "Type A blood" "Excellent explosive power" Dry ear wax "...
This series of novel and interesting data is based on the genetic test results of her oral mucosal cells. In addition to pedigree analysis, it also analyzes physiological characteristics based on gene locus, and details her 9 sports genes, 10 nutritional metabolism, 86 health risks, 31 genetic diseases, 93 drug reactions, and 46 genetic characteristics.
"I finally found a scientific excuse for my weight loss failure. It turned out that my genes were blocking me." Liu Di was excited after seeing the test results. She also noticed that there are indeed some issues that make her happy or worry about health risks and drug reactions. For example, her risk of diabetes is 6.5 times that of normal people, and caffeine metabolism is slow. These all remind her to pay more attention to her lifestyle. And if, like Angelina Jolie, a susceptibility gene for breast cancer is detected, is it a diseased patient? Zhang Ling said that predictive genetic testing is the use of genetic testing technology to detect the risk of disease before it occurs, and it is not equivalent to disease diagnosis in the medical sense. "Accurate genetic test results can tell you how high your risk of developing a certain disease is, and you should prevent it early, but it does not mean that you have already contracted a certain disease, or you will definitely get a certain disease in the future."
"By extracting DNA from oral epithelial cells, a life story can be predicted", which is more of a commercial gimmick. Even at the current stage of medical development, the results of genetic testing of healthy people during asymptomatic periods can only be the "probability of cancer", and it is impossible to determine whether you have cancer now. In addition to the genetic testing performed by Liu Di, it may be able to provide her with personalized health guidance, medication guidance, and personalized physical examination guidance in the future.
"Predicting disease" may still be a surreal ability. But with the popularization of early cancer screening awareness and the promotion of technology, mankind will gradually break the curse of cancer "discovery is advanced" and realize the ultimate pursuit of "preventing disease".
