[Fat Bear Science] You can get lung cancer whether you smoke or not, so do I need to quit smoking?

The World Health Organization (WHO) calls smoking the "fifth threat" to humanity after war, famine, plague and pollution. It is reported that more than 2,000 people die from smoking every day in China, and it is expected to increase to 8,000 by 2050. Among the deaths related to smoking, chronic lung diseases account for 45%, lung cancer accounts for 15%, and esophageal cancer, stomach cancer, liver cancer, stroke, heart disease and tuberculosis account for 40%.

Experts knock on the blackboard

What are the dangers of smoking?

Medically confirmed, each cigarette releases more than 4,000 chemical substances and billions of particles when it burns, including 69 carcinogens such as nicotine, carbon monoxide, tar, ammonia, and benzene.

These harmful substances are inhaled into the human body and adhere to the tracheal walls and alveoli, easily leading to bronchitis, emphysema and even lung cancer; and carbon monoxide can significantly reduce the oxygen content in the blood, causing cardiovascular and cerebrovascular diseases such as high blood pressure and heart disease.

Smoking is not only harmful to your own health, but also to the health of those around you. If someone is smoking around you (also called passive smoking, or second-hand smoke), you not only inhale the exhaled smoke, but also the smoke from the burning cigarettes. This second-hand smoke often causes non-smokers to suffer from diseases, even lung cancer.

Children and infants who live in homes where smokers smoke are more likely to get ear infections, colds, bronchitis, and other respiratory illnesses than children and infants who live in homes where smokers do not smoke. Secondhand smoke also irritates the eyes and causes headaches, nausea, and dizziness.

Q1

"Doctor, I never smoke, how come I got lung cancer? Is this a mistake?"

Smoking does cause lung cancer, but non-smokers can also get lung cancer.

Everyone knows that smoking can cause lung cancer. However, not all lung cancer patients have a history of smoking, and smoking is not the only cause of lung cancer. So besides smoking, what other factors are related to the occurrence of lung cancer? The causes of lung cancer currently known include the following:

1. Smoking is the main risk factor for non-small cell lung cancer

When cigarettes burn, they release carcinogens. 85%-90% of lung cancer can be attributed to active smoking or passive smoking. The incidence of lung cancer in passive smoking patients is 1.24 times that of non-smokers.

The incidence of lung cancer in smokers is related to the number of years of smoking and the number of cigarettes smoked per day. The product of the number of years of smoking and the number of cigarettes smoked per day is called the smoking index. The higher the smoking index, the higher the risk of lung cancer. Those with a smoking index greater than 400 are high-risk groups.

Smoking index = number of cigarettes smoked per day × number of years of smoking

2. Occupational factors: Asbestos exposure significantly increases the risk of lung cancer

People who are exposed to asbestos in occupations such as construction, asbestos mining, insulation material processing, and automobile brake repair are exposed to asbestos. If asbestos fibers are inhaled, they will irritate and damage lung tissue. 3%-4% of lung cancer cases are caused by asbestos exposure.

In addition, the radioactive substance radon gas produced by radium, carcinogenic hydrocarbons, arsenic, chromium, nickel, cadmium, beryllium, silicon, diesel, etc. may all cause lung cancer.

3. Chronic lung diseases: such as tuberculosis, silicosis, pneumoconiosis, etc.

The incidence of lung cancer in patients with these chronic lung diseases is higher than that in normal people. In addition, chronic obstructive pulmonary disease and pulmonary fibrosis scar lesions may cause squamous metaplasia or hyperplasia during the healing process, on this basis, some cases may develop into lung cancer.

4. Other factors: Family history of lung cancer and other tumor histories are related to the occurrence of lung cancer

As you can see, a variety of factors are related to the occurrence of lung cancer. However, smoking still needs to be taken very seriously, because the relationship between smoking and the occurrence of lung cancer is the closest among all related factors.

It should be noted that although the occurrence of all types of lung cancer is related to smoking, the degree to which different types of lung cancer are related to smoking varies.

So what are the different types of lung cancer? And what is their relationship with smoking?

Small cell lung cancer: Nearly 20% of lung cancer patients belong to this type. Small cell lung cancer progresses rapidly and is highly malignant. Patients will have blood metastasis in the early stage and are sensitive to radiotherapy and chemotherapy. The treatment of small cell lung cancer is mainly systemic chemotherapy, which can be combined with radiotherapy and surgery. The occurrence of small cell lung cancer is closely related to smoking. Almost all small cell lung cancers are related to smoking.

Non-small cell lung cancer: About 80% of lung cancer patients have non-small cell lung cancer. Small cell lung cancer patients are mainly treated with chemotherapy, and surgery does not play a major role in patients with this type of lung cancer.

Surgery is more suitable for patients with non-small cell lung cancer. Non-small cell lung cancer is divided into squamous cell lung carcinoma and adenocarcinoma. The occurrence of squamous cell lung carcinoma is also closely related to smoking. Compared with small cell lung cancer and squamous cell lung carcinoma, the relationship between adenocarcinoma and smoking is slightly weaker. Among all non-smoking lung cancer patients, the proportion of adenocarcinoma patients is the highest.

Q2

"I have been smoking for so many years. Is it very likely that I will get lung cancer? What should I do?"

For people at high risk of lung cancer, lung cancer screening should be performed regularly.

The prognosis of early-stage lung cancer and late-stage lung cancer is very different. Therefore, early detection and early treatment are very important. For people at high risk of lung cancer, lung cancer screening is required. So who should be screened for lung cancer? What is the screening method?

Low-dose chest CT is the standard method for lung cancer screening. As we all know, CT examinations have radiation, and the radiation dose of low-dose CT is 1/4 to 1/6 of that of normal CT, so low-dose CT has less radiation damage to the human body.

Although the imaging effect of low-dose CT is worse than that of conventional-dose chest CT, low-dose CT examinations can also detect very small lesions, for example, lesions as small as 5 mm can be detected.

Therefore, for lung cancer screening, low doses are less harmful and more sensitive. However, for people who have lung lesions found by low-dose CT, conventional dose CT is needed to more accurately evaluate the lesions, especially for people with lesions in the mediastinum or possible lesions in the lymph nodes, who need enhanced CT to evaluate the condition.

After understanding the screening methods for lung cancer, we also need to understand which groups of people are at high risk of lung cancer and need low-dose CT examinations.

■ Aged 55-74 years, smoking index ≥30, and has quit smoking for less than 15 years.

■ Aged over 50, with a smoking index ≥ 20, and other risk factors that may increase the incidence of lung cancer (excluding passive smoking).

(Smoking index = number of cigarettes smoked per day × number of years of smoking)

People who meet the above two conditions need to undergo lung cancer screening.

Q3

"Doctor, you said that smokers are more likely to get lung cancer, but I can't quit?"

No, you still have to quit smoking as soon as possible.

For long-term smokers, quitting smoking may be a very difficult thing. During the process of quitting smoking, a series of symptoms may occur, such as irritability, dizziness and headache, insomnia and anxiety, coughing and sweating, decreased heart rate, appetite or weight gain, etc.

We call this phenomenon nicotine withdrawal syndrome, commonly known as smoking cessation syndrome. If you encounter this situation, we don't need to worry, because this is a very normal stage, and you will gradually get better after getting through this stage.

So at this stage we need to be determined to quit smoking and survive this stage to successfully quit smoking. Below we introduce some methods to help you quit smoking.

Why don't you take a notebook and remember it!!!

■ Throw away smoking utensils. Throw away all smoking-related utensils, including lighters, ashtrays, cigarettes, etc., to reduce the probability of triggering the "conditioned reflex" of smoking.

■ Use alternatives. When you feel the urge to smoke, use chewing gum, electronic cigarettes, etc. to replace cigarettes. You can also eat sunflower seeds, your favorite food, etc.

■ Maintain good living habits, drink more water or juice, eat more fruits, exercise moderately, maintain a regular work and rest schedule, and relieve mental stress.

■ When you feel the urge to smoke, take deep breaths immediately or chew sugar-free gum. Avoid replacing cigarettes with snacks, otherwise it will cause your blood sugar to rise and you will become overweight.

■ Firmly resist the temptation of cigarettes and remind yourself frequently that smoking one more cigarette is enough to ruin your plan to quit smoking.

■ For those who find it difficult to quit smoking, nicotine replacement therapy can be used to quit smoking. Nicotine replacement therapy or non-nicotine drug therapy often helps smokers quit smoking successfully. Nicotine replacement therapy is the use of items rich in trace amounts of nicotine, such as smoking cessation chewing gum, inhalers, nasal sprays, patches, etc., to help smokers relieve symptoms such as irritability, insomnia, anxiety, etc. during the process of quitting smoking.

The method is to know

How should you get through the first five most difficult days of quitting smoking?

Don't panic

Super Cheats Here

■ Drink 6-8 glasses of water between meals to help excrete nicotine from the body

■ Take a warm bath every day, and take a shower immediately when you can't resist the urge to smoke

■ Get enough rest and have a regular life during the 5 days of quitting smoking

■ After dinner, take a walk outside and do deep breathing for 15-30 minutes

■ Avoid stimulant drinks and drink milk, fresh juice and cereal drinks instead

■ Avoid poultry, fried foods, sweets and desserts

■ You can take a variety of B vitamins to calm your nerves and remove nicotine

I survived the first five painful days.

Also pay attention to these points

In order to maintain the previous "results"

■ Brush your teeth or rinse your mouth after meals and wear clean clothes that do not smell of smoke

■ Use a pen or pencil instead of holding a cigarette

■ Spend most of your time in libraries or other places where smoking is not allowed

■ Avoid going to bars and parties, and avoid being with people who are heavy smokers

■ Use the money you save from not smoking to buy yourself a gift

■ Prepare to quit smoking within 2-3 weeks and keep it up for a long time

Text/ Fat Bear

Image/ Internet (please contact us to delete)

Review/ Wang Feng

Original article, no reproduction without authorization

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Science Popularization China Co-construction Base

Chongqing Science Popularization Base/Chongqing Health Promotion Hospital

Chongqing Municipal Science and Technology Commission Science and Technology Communication and Popularization Project

National Health Commission National Basic Public Health Service Health Literacy Project