Most people are aware that by far the biggest cause of lung cancer is tobacco smoke, whether it be via active smoking of cigarettes or cigars, or exposure to environmental tobacco smoke pollution (secondhand smoke). Many people are still surprised to learn that lung cancer kills more women than breast cancer. The risks of lung cancer increase dramatically with age and years of tobacco smoking. Men who continue to smoke are over 20 times more likely to die of lung cancer compared with men who have never smoked. At age 75, never smokers have a cumulative risk of lung cancer of less than one percent. Those who smoked but quit at age 50 have a cumulative risk of lung cancer by age 75 of 6%. Those who continue smoking have a cumulative risk of lung cancer by age 75 of over 16%. So it is clear that quitting smoking reduces the risks of lung cancer, even if you have smoked for decades. However, the risks do not return to those of a never smoker and it takes about 15 years without smoking for the increased risks to be cut in half.
Environmental tobacco smoke pollution also causes lung cancer. This cause accounts for a significant proportion of the never smokers who get lung cancer. So living with someone who smokes in the home, or working in an environment where people smoke (e.g. a bar, restaurant or casino) will significantly increase your lung cancer risks even if you never smoked yourself. This is part of the reason why many countries and states have passed laws to prevent smoking in workplaces (and remember, bars, restaurants and casinos are workplaces too). Its also part of the reason that many homes have also become smoke-free – requiring family, friends and guests who smoke to take it outside rather than pollute the air inside the home with carcinogens.
Unfortunately the 5-year survival rate for lung cancer remains very low – around 15%, and so far there has not been very convincing evidence that going for CT scans is particularly effective in detecting curable lung tumors at an early stage (without giving false-positives causing unnecessary treatment).
On the positive side, lung cancer is largely preventable on an individual level by not smoking and by avoiding smoky places. On a national level too, we know how to prevent most lung cancer, by implementing comprehensive tobacco control policies including smoke-free workplace legislation, increasing cigarette taxes, hard-hitting mass media educational campaigns, and providing effective smoking cessation treatments. For reasons not entirely unrelated to political campaign contributions from tobacco companies, successive governments have chosen not to adequately fund these effective lung cancer prevention efforts – even though they happen to prevent heart disease, respiratory disease and numerous other illnesses at the same time.
At this moment the President of the United States has promised to veto legislation that has been approved by both the Senate and Congress to increase cigarette taxes to pay for health insurance for poor families. Protecting the tobacco industry in this way leads directly to many more cases of lung cancer.
The symbol for lung cancer awareness is a clear ribbon – symbolic of the “invisible cancer” that receives far fewer dollars for prevention and treatment or public attention than other types of cancer.
For those wishing to learn more about the ways that tobacco harms health, some colleagues and I have just published a fairly detailed review of the health effects of tobacco as a chapter in a new book . You can access the pdf of this chapter via the following link: