The relationship between disease screening and physical examination

Disease screening is a "targeted sniper" examination for specific diseases, while general health examination is a "comprehensive mine-sweeping" routine assessment for general health problems. The two are cross-complementary and non-subordinate relationships - neither includes the other, nor can they replace each other. The popular sayings that "a routine physical examination does not require special screening" and "a cancer screening is equivalent to a full physical examination" are completely wrong perceptions.

Last year, when I was helping out at a community cancer early screening free clinic, I met 62-year-old Aunt Zhang. She was standing at the information desk holding the newly issued physical examination report for retired employees of her employer. She said in a very aggressive tone: "Everything on my report is normal, and the chest X-ray said there is no problem. Why do you have to ask me to do an additional low-dose CT? Isn't this just trying to defraud money?" I looked through her report. Indeed, the blood routine, liver and kidney function, and abdominal ultrasound were all within the normal range. The chest X-ray column also said "no obvious abnormalities." However, her personal history clearly stated that she had a 30-year history of smoking, at least one pack a day, and was a clear high-risk group for lung cancer. The resolution of ordinary chest X-rays could not detect early lung nodules below 1 cm. This low-dose CT was a disease screening specifically for her high risk, and was not covered by the general physical examination at all.

It seems that many people have a vague sense of the boundary between the two. A general health check-up is essentially more like a "regular annual review" of your body every year. It checks the most universal items: height and weight, blood and urine routine, liver and kidney function, and basic ultrasound chest X-ray. Whether you are a 20-year-old girl who just joined the job or a 50-year-old employee who is about to retire, the unified physical check-up package provided by your employer basically includes these items. It is mainly used to discover common health problems that are common at the public level - such as whether there is high blood pressure, high blood lipids, whether there are thyroid nodules, and fatty liver. These problems have no clear population orientation and may occur in adults. Universality is its advantage, but it is also destined to be unable to take into account everyone's specific disease risks.

From the very beginning, disease screening was not prepared for everyone. You see, the two cancer screenings promoted by the state for free are only for women of the right age between 35 and 64 years old, and will not be done for men or women under 35 years old. Colonoscopy screening for colorectal cancer is first recommended for high-risk groups over 40 years old with a history of intestinal polyps or a family history of colorectal cancer. If you are a 20-year-old young man with no digestive tract symptoms and seek a doctor for a routine colonoscopy, you will most likely be persuaded to go back.

Having said this, I must mention that there are now different opinions on the boundaries of screening in the academic community. One group advocates "early screening and early benefit" and believes that as long as economic conditions permit, the screening that can be done should be done as early as possible, even if it is routine gastroenteroscopy at the age of 30, which can nip the risk of early cancer in the bud; the other group insists on "avoiding excessive screening". The official guidelines of the WHO also clearly mention that for ordinary people without high-risk factors, routine gastrointestinal endoscopy is not recommended before the age of 40. Gastrointestinal endoscopy is not recommended for ordinary healthy people to use PET-CT as a routine physical examination - after all, this type of invasive examination itself has a very low probability of side damage, and the radiation dose of PET-CT is not small. On the contrary, it will bring unnecessary burden to people who are not at high risk. Even problems such as small pulmonary nodules that have a high probability of being benign after detection will cause unnecessary anxiety.

Of course, the two are not completely separated. Nowadays, many personalized physical examination packages have included screening items for high-risk diseases in the optional range, such as low-dose CT for smokers and combined HPV and TCT screening for women of appropriate age. You can add corresponding screening items according to your own situation during routine physical examinations without having to go to the hospital twice.

But don’t blindly choose the “most expensive and most comprehensive” package just to save trouble. I met a 30-year-old young man at the outpatient clinic last month. He bought a high-end physical examination package worth more than 20,000 yuan, and selected all the cancer screening options that could be added. He even had a PET-CT. The result was that a 2mm tiny nodule was found in his lungs. He was so scared that he slept all night. No, he went to the thoracic surgery department of three hospitals in a row, and finally the doctors told him that the nodule was basically benign, and that he could just review it once a year. There was no need to do PET-CT. The amount of light radiation was equivalent to ten low-dose CT scans. It was just a waste of money and suffering.

In fact, ordinary people don’t have to worry about “should I have a physical examination or a screening?” They can just answer three points for themselves: Do you have a family history of related diseases? Do you have any long-term high-risk habits (such as smoking, drinking alcohol, eating heavy oil and salt, irregular work and rest)? Is your age in the high-risk range for this type of disease? For example, women with a family history of breast cancer can replace breast ultrasound in routine physical examinations with mammography + ultrasound after the age of 35; smokers who smoke all year round should have a low-dose CT scan every year, regardless of whether it is included in the physical examination package; people over 40 years old, even if they have no symptoms, are recommended to have a baseline gastrointestinal endoscopy. If there is no problem, a re-examination every 3 to 5 years will be enough. There is no need to pursue "big and comprehensive".

After all, whether it is a routine physical examination or a disease screening, they are essentially tools to help you prevent diseases at an early stage. No one is more advanced, and no one can replace the other. Instead of worrying about the relationship between the two, it is better to spend two more minutes thinking about your physical condition and choose the combination that suits you best. This is worse than anything else.