Disease screening is

Disease screening is essentially a secondary prevention measure in the tertiary prevention system. It is also a universal health intervention method at the intersection of public health services and clinical medicine. The core goal is to detect and intervene early before the disease has obvious symptoms, so as to reduce the risk of severe illness and death.

Last year, when I was helping with cancer screening education at the community public health service station, I met many residents who equated screening with ordinary physical examinations. Aunt Zhang, who lives in Building 3, refused to come at first, saying that she usually had no pain or itching, so what was she doing with her time? In the end, the grid officer brought her husband with her, and she did a check-up without hesitation. The result was that the high-risk HPV type 16 was found. A subsequent colposcopy biopsy revealed that it was a precancerous lesion, which was solved with a minor operation. Now everyone says that the screening saved her life.

However, regarding the positioning of screening, there are actually different voices in the industry. When I was chatting with a friend from the Centers for Disease Control and Prevention, he repeatedly said that screening from a public health perspective must first ensure coverage. Even if there is a certain proportion of false positives, it doesn’t matter. After all, the cost of missing a late-stage case is much higher than a few more false positive cases that need to be reviewed. But I had dinner with Director Zhang from the oncology department before, and he put forward another view: Many people are so anxious that they can't sleep all night because of abnormal indicators detected by over-screening. There are even healthy people who have undergone unnecessary invasive tests because of false positives in the screening, and have suffered in vain. For example, in the prostate-specific antigen screening that was routinely promoted in the past few years, many middle-aged and elderly men underwent punctures because the indicators were high. In the end, it was found that it was a false alarm, and there were short-term sequelae of hematuria.

In fact, there is nothing wrong with both statements, they just have different standpoints. If you look at the public health system with a population of tens of millions, you must give priority to ensuring coverage and reducing missed diagnoses; but from the perspective of individual patients, of course, you want to be as accurate as possible, and it is best not to have redundant tests. The current screening plans in various places are actually a compromise plan worked out by experts from two groups. For example, colorectal cancer screening requires fecal occult blood and multi-target gene testing first, and then a colonoscopy if it is positive. There is no need for everyone to come in for a colonoscopy, which not only saves medical insurance money, but also reduces the pain of ordinary people.

Many people can’t tell the difference between screening and general physical examination. When I explain it to residents, I usually use an analogy: the physical examination you do every year is like a full car maintenance, checking everything for peace of mind; and disease screening is like going to a 4S store to check the brake pads and tire wear when you often drive on the highway. It is a precise examination for specific diseases and specific high-risk groups, and is not suitable for everyone. Don’t underestimate the difference between the two. Choosing the wrong one will not only cost you money, but may also add unnecessary burden to yourself. For example, lung cancer screening only recommends low-dose spiral CT for people who have been long-term smokers, have a family history of lung cancer, and are occupationally exposed to carcinogens. If you are a non-smoking girl in your early twenties and you ask for lung cancer screening, you will end up getting radiation in vain, which is completely unnecessary.

When I was sorting out the screening data in my jurisdiction, I found that many institutions promote a full set of cancer screenings to everyone in order to make money. In fact, they are really doing bad things with good intentions. I met a 19-year-old girl before who was deceived by a private institution to do a cervical cancer screening and was found to be HPV positive. She cried for several days and came to us for consultation. I told her that most HPV infections at this age are transient. As long as there is no problem with TCT, there is no need to deal with it at all and regular re-examination will be enough. She felt relieved.

To put it bluntly, disease screening is never a magic medicine that "everything will be fine after checking it", nor is it a useless method of "looking for a disease when there is no disease". It is just a tool to help you identify health risks in advance. How to use it and who to use it for depends on your age, family history, and living habits. Don't blindly follow the trend, and don't resist blindly with a sense of luck. That's enough.