The latest research: Smoking is the culprit for nearly 20 types of cancer, and quitting smoking has many benefits!

Lung cancer is the most common malignant tumor in my country, and an important factor leading to lung cancer is tobacco. The nitrosamines, polycyclic aromatic hydrocarbons, benzopyrene, etc. in tobacco are highly carcinogenic to the respiratory system. Both smoking and secondhand smoke will increase the risk of lung cancer.

Despite this, quitting smoking is still very difficult! Many cancer patients do quit smoking for a period of time after being diagnosed with cancer, but soon start smoking again. According to published data, 64% of patients continue to smoke after being diagnosed with cancer.

So, what survival benefits does quitting smoking bring to cancer patients? How does the risk of cancer death differ between patients who have never smoked, quit smoking after diagnosis, and continue to smoke after diagnosis?

Recently, researchers analyzed data from 128,423 cancer patients with 23 types of cancer at the University of Texas MD Anderson Cancer Center, giving us a comprehensive understanding of the association between smoking status, smoking intensity, starting age, smoking cessation at cancer diagnosis, and all-cause mortality.

Among the 128,423 cancer patients included in this study, 63,649 patients (49.6%) had never smoked before diagnosis, 50,716 patients (39.5%) had smoked before diagnosis but no longer smoked, and 14,058 patients (10.9%) were still smoking at the time of diagnosis.

The average median follow-up time of the study was 7.6 years, and 53,817 people died during the follow-up (accounting for 41.9%). Overall, non-smokers lived the longest

According to the overall data of the study, patients who have never smoked have the highest overall survival rate, while patients who continue to smoke after diagnosis have the worst survival rate.

After adjustment for variables, the HR for former smokers was 1.09 (95% CI 1.06-1.11) and the HR for current smokers was 1.19 (95% CI 1.16-1.23) compared with never smokers.

Looking at the life expectancy data, the contrast is even more obvious: compared with patients who have never smoked, the life expectancy of patients who used to smoke but have quit smoking is shortened by 3.7 years; and for patients who are still smoking, the life expectancy is shortened by 5.9 years!

The earlier you start smoking and the more you smoke , the greater your risk of death

The more cigarettes a person smokes per day, the greater their risk of death compared to people who have never smoked.

Compared with people who never smoked, the HRs for people who smoked ≤10 cigarettes, 11-20 cigarettes, and ≥21 cigarettes per day were 1.15 (95% CI 1.08-1.24), 1.27 (95% CI 1.20-1.34), and 1.32 (95% CI 1.24-1.41), respectively.

There is also a corresponding correlation between the age of starting smoking and the risk of death. The researchers divided the subjects into three groups according to their age, namely ≤17 years old, 18-25 years old, and ≥26 years old. The corresponding HRs for death risks were 1.17 (95% CI 1.05-1.30), 1.24 (95% CI 1.16-1.32), and 1.32 (95% CI 1.24-1.41), respectively.

This research result tells us that the earlier a patient starts smoking, the longer they smoke, and if they continue to smoke after being diagnosed, their risk of death will increase significantly.

Therefore, the age of smoking has a direct relationship with the risk of cancer death, just like the amount of smoking. Smoking is not only related to lung cancer, but can also increase the risk of death from nearly 20 types of cancer.

In many people's cognition, smoking mainly leads to an increased risk of incidence and death from lung cancer.

The researchers analyzed the link between smoking and 23 different common cancer types.

The results showed that smoking is associated with an increased risk of death from up to 20 types of cancer, and the increased risk of death from 9 types of cancer is statistically significant!

Patients who were former smokers but had quit had a reduced risk of death from multiple cancers compared with those who were still smoking. Smoking status was significantly associated with the risk of death in most subgroups.

How beneficial is quitting smoking for cancer patients?

The most obvious result is that quitting smoking can reduce patients' risk of death from all cancers.

Compared with patients who are still smoking, patients who have quit smoking have a lower risk of death from all cancers, and the longer they quit smoking, the greater the reduction in their risk of death. The risk of death for patients who have quit smoking for 5 years, 5 to 10 years, 10 to 20 years, and more than 20 years has been reduced by 3%, 5%, 11%, and 15%, respectively!

Of course, compared with patients who smoked after diagnosis, patients who never smoked had the largest reduction in death risk, reaching 20%!

The findings provide strong evidence that continuing to smoke after diagnosis increases a patient's risk of death.

For people who already smoke, it is never too late to quit smoking and it can bring certain health benefits.