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Overall, lung cancer is a disease with very poor prognosis. While we cure close to 85% of all breast cancer, that’s basically the mortality rate for lung cancer overall. We only cure about 15% of lung cancers.
The top three risk factors for lung cancer?
Tobacco. Tobacco. Tobacco.
Years ago I wrote an Op-Ed piece for our local newspaper, and I received a gratifying letter from an elementary school teacher who said it was the first time she understood cancer risks; she used it to explain cancer to her grade five students. So the description must have resonated.
The code that runs our cellular metabolism is housed in our DNA, and ALL cancer is a result of mutation in that DNA—not necessarily in the genome that you inherit—rather in some poor cell that mutates while doing its routine thing in your body. The defining characteristics of a cancer cell are many and may differ from cell to cell, but share the basic fundamental defect of loss of proliferative control. Like rabbits, they don’t know when to stop.
DNA can be mutated by stray packets of energy: electromagnetic, chemical, viral (which is really chemical, sort of). There are lots of them: carcinogens, radiation, infection. The type doesn’t matter much until you want to restrict your exposure to them. Just think of them as little packets of energy hitting the molecules of DNA in just precisely the right spot, out of literally billions of possibilities.
So the analogy I used for those elementary school children was shooting at a proverbial needle in a haystack with a machine gun. If you miss the needle, nothing much happens. If you hit the needle, cancer.
The kids were able to appreciate that if you shot just one bullet into a big haystack, there was a pretty big chance you would miss the needle. But if you spent all day blasting at it with millions of bullets from an AK47, well, your chances of hitting the needle just went up a lot.
So people who live pretty healthy lives can still get cancer if one stray photon of energy hits the DNA at just the right energy in just the right place. It actually probably takes more than one, but you get the idea. It’s rare to get cancer unless you increase your risks, increase the number of those packets of energy. And we know the effectiveness of those risks from research.
Smoking exposes our DNA to so many risks, from all the chemicals in cigarette and pipe and cigar smoke, that smoking is really like shooting at the haystack with an AK47. At some point, if you do it enough, you hit the needle. Or maybe not. Maybe you can do it all your life and get away with it, if you’re really really lucky.
Like Clint Eastwood said, “Do ya feel lucky, punk? Do ya?”
A stat I have held in my head for forty years: 1 in 6 smokers get lung cancer, 1 in 77 non-smokers get lung cancer.
Oh, there are other risks that a can shape this, like radon, asbestos (even for non-mesothelioma cancers), heavy metals like chromium, nickel, but by far the vast majority is from smoking. In fact, EVERYTHING is dwarfed by smoking. No contest. 85% to 90% of lung cancers are caused by smoking!
The epidemic of lung cancer we are in right now is a direct result of cigarette smoking. Mortality rates from lung cancer prior to the Great Depression were in the same ball park as leukemia and cancers of the pancreas and liver, and were actually lower than prostate/breast, colon, rectum and stomach. About 5 to 10 per 100,000.
But in 1992, new cases of Lung Cancer reached 69.5 per 100,000 according to SEER databases (deaths peaked at 59.1). If you look at the graph above from the American Cancer Society, which is massaged in a different way, deaths actually approached 80 to 100 per 100,000. The actual number depends on how you interpret the data, but really is not as important as the trend. Deaths have been descending ever since1992/3, as North America has finally awakened to the reality of the risks of smoking. In the last decade the numbers of new cases (SEER data again) got down to less than 54 per 100,000 (deaths down to 45), and some day they’ll get back down closer to the pre-depression levels, all because fewer people are smoking. It is one of the major life-style changes of the last century.
These numbers vary wherever I look them up, but the trend is always the same. Lung cancer is about one tenth the incidence in non-smokers compared to smokers, and the number of smokers has been going down in recent years, at last. So death from Lung Cancer has been dropping accordingly.
Admittedly, better treatment has increased survival rates of those who get the cancer: in the last fifty years from about 11% to about 18% five year survival. Wow. 7% improvement in fifty years.
Not very good, no matter how you massage the numbers. So, if you have a choice, don’t treat the Lung Cancer–avoid it. Reduce your exposure to cigarette smoke and you reduce your risk. Don’t model smoking to your kids. Don’t let others smoke around you. Don’t let people smoke in your house.
If you want to stamp out lung cancer, stamp out cigarettes.
Take a look at this link: