Quitting Smoking Triggering Lung Cancer?

Factual Questions
1

Mom’s friend, who has lung cancer, told Mom that his doctor actually said that his quitting smoking might have “triggered” the cancer, and that he would have been better off had he kept smoking.

Me to Mom: Your friend misunderstood. Or is making it up. Maybe he’s just looking for an excuse to start smoking again.

Mom: He wouldn’t make it up, and he swears he didn’t misunderstand.

Okay, I wouldn’t even be bothering you dopers with this, because it’s so, well, you know, lame – but then I mentioned it to a couple friends at work, saying, “why does my Mom believe this kind of garbage” – and they both said, “oh, it really can happen; any change in the metabolism, yada yada”.

Huh?
Anyone else believe this? (I mean, anyone actually schooled in causes of cancer, that is? I’m sure not…)

Thanks.

2

Sometime back in the 1990s, I read an article that was responding to the question about “Why does it seem that some people seem to develop cancer shortly after they quit smoking?”

I’m quite foggy on the details, but what it basically boiled down to the fact that they had already developed cancer, it just hadn’t been diagnosed yet, and the lung cancer made it easier to quit.

Their bodies were less-than-enthusiastic about more smoke, so the smokers weren’t enjoying cigarettes as much as they used to, but they may not have been actively aware of why. They just sort of though “I don’t like this as much anymore, I think I’ll quit.” Then within a year their symptoms worsened, they sought medical advice (after all, they aren’t smoking anymore, so why the cough?), and they were diagnosed with lung cancer. So taken at face value, it looks like “quitting” = “cancer within a year”.

As I said, that’s from some newspaper article I vaguely recall from probably more than ten years ago, so take that with a big grain of salt. You might be able to use that as a starting point for googling though.

3

The primary risk factor for developing various types of lung cancer is smoking but this is based on correlation; although we know that there are some cofactors for developing lung cancer (like asbestos exposure with mesothelioma), there really isn’t a good understanding of why or how lung cancers start and why smoking aggrevates it.

However, it’s unlikely to the point of certainty that quitting smoking triggers lung cancer. Most lung cancers develop slowly and can progress for months or years before detection. Because the lungs are so blood-rich and intimately tied in with the circulatory system, lung cancer often metastasizes before discovery. Peter Jennings credited his lung cancer from resuming cigarette smoking after September 11, 2001, but there’s a good chance that the cancer was already developing (though starting to smoke again probably didn’t help any, and may have masked symptoms).

Lung cancer due to smoking starts showing up about 20 years after starting to smoke and onward…which is about the same time (late thirties or early forties) when many people start quitting smoking. This will tend to create a bias of people incidentially developing cancer at the same time they quit, and in fact there’s a very good correlation between when mass produced cigarettes (with added products to preserve the tobacco and enhance nicotine delivery) became available and a pronounced rise in the incidence of lung cancer with a 20 year lag, and as people smoked more cigarettes per year (due in part to filtration and smoother, low tar tobacco) the cancer rate increases.

Note that cancer from smoking untreated tobacco (unprocessed pipe and cigar tobacco, natural cigarettes) tends to be substantially lower than commerical cigarettes. Speculation for this includes that people smoke less, or don’t inhale as much or as long, or don’t smoke as often, but dollars to donuts that a lot of it has to do with chemicals added to tobacoo used in mass produced cigarettes during processing, many of which are known carceneogens.

Your mother’s friend’s doctor is on crack if that’s what he told her. While their are ignorant, Frank Burns-ish physicians out there, I’m going to guess that the tale was somewhat mangled in the telling somewhere between the doctor and your mum, however.

Stranger

4

[QUOTE=Stranger On A Train]
…good chance that the cancer was already developing (though starting to smoke again probably didn’t help any, and may have masked symptoms).

[/QUOTE]

I wonder if that’s what led to a misunderstanding by the patient:
Doc says “your cessation of smoking could have uncovered the (previously-masked) symptoms”
Patient, defining “symptoms” incorrectly, and paying no attention to the parenthetical phrase, which perhaps was not uttered, interprets this as “quitting could have caused the cancer”

Hmm.

An additional curiosity: My co-workers are both intelligent people. They vigorously proclaimed that “any change in metabolism can trigger a cancer”. I don’t understand that, nor do I understand why quitting smoking would change one’s metabolism.

5

[QUOTE=Another Primate]

An additional curiosity: My co-workers are both intelligent people. They vigorously proclaimed that “any change in metabolism can trigger a cancer”. I don’t understand that, nor do I understand why quitting smoking would change one’s metabolism.
[/QUOTE]

Never confuse intelligence with knowledge (or stupidity with ignorance, for that matter).

If Mom’s doctor said anything close to what the friend quoted, he’s an idiot along with your friends who are passing along a folklore explanation as if it were some sort of scientific gospel.

Anyway, consider that the doubling time of lung cancers might range from 100 or so days to 250 days (in round numbers; here’s an example reference http://jjco.oxfordjournals.org/cgi/content/abstract/24/4/199 ). Extrapolate that out and it’s easy to see why you may need 10 or 20 years to get clinically significant cancers from the point at which the actual cancer began.

This is also why it is so critical for people to understand that you don’t get to smoke risk-free from age 15 to 30, and then quit. You may have a cancer that started when you were 20 and shows up at age 40 even if you quit at age 25. The last three lung cancers I diagnosed on presentation to my Emergency Department were 10, 12, and 15 years out from when the patients had quit smoking.

There are some unfortunate folks (see Stranger’s comments) who happen to get diagnosed fairly proximate to when they quit. Total coincidence. Those cancers started many years before. That it showed up just after they quit has nothing to do with quitting.

FWIW, the pathophysiology underlying coronary artery disease is similar, with the same sad ignorance. “I quit smoking and three years later I get a heart attack. It’s just not fair.” Yeah buddy; but the pathology triggered by your smokes started 20 years ago.

6

[QUOTE=Chief Pedant]
Extrapolate that out and it’s easy to see why you may need 10 or 20 years to get clinically significant cancers from the point at which the actual cancer began.

This is also why it is so critical for people to understand that you don’t get to smoke risk-free from age 15 to 30, and then quit. You may have a cancer that started when you were 20 and shows up at age 40 even if you quit at age 25.
[/QUOTE]

Just playing devil’s advocate here… doesn’t that suggest that there may not be a great benefit to stop smoking after 20 or 30 years?

Take a 65-year old woman who has smoked for forty years. If she has already developed lung cancer that has not yet been detected, she won’t save herself if she stops now. Similarly, if she has no cancer now, she could still develop lung cancer, but would be at the outside range of her normal life expectancy before it became lethal. As for heart disease, whatever damage has been done can’t be undone, right?

7

[QUOTE=anson2995]
Just playing devil’s advocate here… doesn’t that suggest that there may not be a great benefit to stop smoking after 20 or 30 years?

Take a 65-year old woman who has smoked for forty years. If she has already developed lung cancer that has not yet been detected, she won’t save herself if she stops now. Similarly, if she has no cancer now, she could still develop lung cancer, but would be at the outside range of her normal life expectancy before it became lethal. As for heart disease, whatever damage has been done can’t be undone, right?
[/QUOTE]

Not the devil’s advocate-- RJ Reynolds’ advocate. :smiley:

Great question…and you are right to a large extent.

There is much less point in stopping smoking after about 60, except perhaps to make chronic lung disease more manageable (and maybe to slow down its progression since chronic lung disease is sort of a dose-related progression). This is a rogue position with respect to what most doctors will tell you, and worth what you are paying for it (less the $15 fee for SDMB membership) but if someone wants to argue it, ask 'em for data.

For cancer and heart disease, though, quitting after 60 or so only returns a few years of life. This has not been extensively studied, but there was a study in the British Medical Journal a few years ago that was fairly well done:

“Cessation at age 60, 50, 40, or 30 years gained, respectively, about 3, 6, 9, or 10 years of life expectancy” http://www.bmj.com/cgi/content/abstract/bmj.38142.554479.AEv1

It’s also probably just fine to start smoking around 55 or so, for the same reason. :wink: Back when I was an Internist I never bothered my elderly smokers about their habit. Of course I swapped specialties which should tell you something.

8

[QUOTE=Chief Pedant]
There is much less point in stopping smoking after about 60, except perhaps to make chronic lung disease more manageable (and maybe to slow down its progression since chronic lung disease is sort of a dose-related progression). This is a rogue position with respect to what most doctors will tell you, and worth what you are paying for it (less the $15 fee for SDMB membership) but if someone wants to argue it, ask 'em for data.
[/QUOTE]
I’m not disputing your statement, but stopping smoking can slow the progression of non-cancer and heart disease-related health effects, and of course reduces real (if unquantifiable) effects from second-hand smoke to associates of the smoker. From an environmental standpoint, it also reduces litter and the effects of tobacco farming, albeit to an insignificant degree on an individual level. But the health effects to a chronic smoker of quitting after several decades of smoking are minimal at best, to be sure.

Stranger

9

While I think the OP has been sufficiently answered, I’ll just throw in this anecdote:

My mother died almost two years ago, nine days after falling suddenly ill with respiratory problems: lung cancer so far advanced that treatment was not even an option. We could only keep her doped up on painkillers until the end.

That she had not shown any symptoms of the illness until the very end is atypical, but not unusual. What did surpise us, though, was the apparent suddenness of the onset. Just a year earlier, she had been admitted with breathing problems, and, knowing her history of smoking, they checked pretty thorougly for signs of cancer. None to be found. Her breathing problems had been caused by an allergic reation to some medication (a medication she had never received before), and not by cancer.

After her diagnosis of cancer, her case was the topic at a hospital staff meeting. They brought out all her Xrays and scans from the year earlier, and went back over them, to see if whether there had been anything they missed. Their conclusion: They still could not find any indication of cancer. Now, the doctor (a pulmonary critical care specialist) did say that he couldn’t guarantee that there were no cancer cells in her body at that time, but if there were, they didn’t form a tumor big enough to be picked up on any of the imaging.

Point being, while 100-250 days for doubling might be typical, it apparently can also be dramatically faster.

10

[QUOTE=Another Primate]
Me to Mom: Your friend misunderstood. Or is making it up. Maybe he’s just looking for an excuse to start smoking again.

Mom: He wouldn’t make it up, and he swears he didn’t misunderstand.
[/QUOTE]
By definition, if he misunderstood he wouldn’t be aware of it.

11

[QUOTE=Chief Pedant]
For cancer and heart disease, though, quitting after 60 or so only returns a few years of life. This has not been extensively studied, but there was a study in the British Medical Journal a few years ago that was fairly well done:

“Cessation at age 60, 50, 40, or 30 years gained, respectively, about 3, 6, 9, or 10 years of life expectancy” http://www.bmj.com/cgi/content/abstract/bmj.38142.554479.AEv1
[/QUOTE]
“Only three years” will still sound pretty good to a lot of 60-year-olds, given that there may not be a whole lot of years left at that point.
People will undergo not very pleasant cancer therapy to gain extra months in some cases.

And there is of course the benefit to the people around the quitting smokers, who will be spared the risks related to secondhand smoke.

I agree that there is zero evidence that a “change in metabolism” in people quitting smoking triggers any cancer development. Those who believe this are putting faith in coincidence and anecdote, and/or looking for excuses not to quit.

12

[QUOTE=Askance]
By definition, if he misunderstood he wouldn’t be aware of it.
[/QUOTE]

Laugh, good point!

13

This goes to the “any change in metabolism” issue: a friend of mine was undergoing chemo for testicular cancer a several years ago (at the ripe old age of 20 :frowning: ). He was a heavy smoker and smoked right through the cancer treatment. When I asked him about it, his doctor told him that it would be worse for him to suffer through nicotine withdrawal than it would be for him to continue smoking at that point, so he gave him the OK to keep smoking. That got a :dubious: from me but I kept my mouth shut. What do you think?

14

[QUOTE=Rubystreak]
This goes to the “any change in metabolism” issue: a friend of mine was undergoing chemo for testicular cancer a several years ago (at the ripe old age of 20 :frowning: ). He was a heavy smoker and smoked right through the cancer treatment. When I asked him about it, his doctor told him that it would be worse for him to suffer through nicotine withdrawal than it would be for him to continue smoking at that point, so he gave him the OK to keep smoking. That got a :dubious: from me but I kept my mouth shut. What do you think?
[/QUOTE]
Smoking might have helped suppress the nausea and other physical ailments that are side effects of chemotherapy, and conversely the stress of suddenly quitting smoking might have both exacerbated physiological effects and exaggerated despression and anxiety from dealing with a major illness. I’d be surprised if the doctor didn’t tell him to cut down if he was a heavy smoker, but it wouldn’t surprise me that he advised him not to quit. I haven’t seen any studies or evidence that smoking interferes with or decreases the efficacy of chemotherapy treatments beyond than the nominal hazards of smoking. It’s nearly certain that smoking, especially at such a young age, was not an applicable risk factor for his testicular cancer, and your friend’s age is typical for development of these types of cancers.

Stranger

15

[QUOTE=Rubystreak]
[The] doctor told him that it would be worse for him to suffer through nicotine withdrawal than it would be for him to continue smoking at that point, so he gave him the OK to keep smoking. That got a :dubious: from me but I kept my mouth shut. What do you think?
[/QUOTE]

Another anecdote: My aunt got the same advice when she was being treated for breast cancer. I had the same two reactions.

16

My mother (who died from lung cancer) believed this sort of nonsense for most of her life. She tried to quit smoking in the 1970s, came down with bronchitis, and concluded that there was a causal relationship there. Until the day she was diagnosed with lung cancer, she insisted that cigarettes kept her healthy.

Incidentally, if you want an earful of this kind of hooey, go hang around a theater (professional or community theater, not a movie theater). Actors and other showbiz people are the most unrepentant smokers around, and will regale you for hours with tales of Aunt Hazel who chain-smoked Camels and lived to be 106. This is, incidentally, why there’s so much smoking in plays and movies; the actors can’t go 10 minutes without a cigarette, so they announce “I’ve decided my character smokes.”

17

[QUOTE=chimera222]
This is, incidentally, why there’s so much smoking in plays and movies; the actors can’t go 10 minutes without a cigarette, so they announce “I’ve decided my character smokes.”
[/QUOTE]

Maybe in plays, but not in movies. Pretty much every puff is paid for by the Tobacco industry. Try watching “Thank you for Smoking” sometime.

So, unless it is something like an Edward R Murro Bio, then the smoking you see on screen is largely there as a bought and paid for Cig ad.

18

Both my parents quit smoking and both came down with cancer. Dr. told me that it is a well know secret through the medical world that anyone who smokes will get cancer. My Dad smoked 3 to 4 packs a day, died less than a year after quiting. My Mom smoked 1 pack a day and she was dead less than 3 months from the day she quit. Makes you wonder just how much information, truthful information, we are receiving on any matter. I, personally, do not trust anything I read as all information is slanted.

19

Bolding mine. By this metric, it would be apparent that this information you’ve imparted here is suspect. A well-known secret throughout the medical world? Anyone who smokes? :dubious: Sounds like this “Dr.” is blowing smoke up your ass.

Just sayin’.

20

Damn, and I revealed the secret here on the Dope! Now They will have to kill me. :frowning:

Hot tip: If you see a smoker shambling towards you muttering “brainsss…” just blow their head off, assuming your concealed carry license is in order.