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65% of Cancers Caused by Bad Luck, Not Genetics or Environment

BarbaraHudson writes The Wall Street Journal and the CBC are reporting that about two-thirds of cancers are caused by random chance. From the WSJ: "The researchers, from the Johns Hopkins University School of Medicine in Baltimore, analyzed published scientific papers to identify the number of stem cells, and the rate of stem-cell division, among 31 tissue types, though not for breast and prostate tissue, which they excluded from the analysis. Then they compared the total number of lifetime stem-cell divisions in each tissue against a person's lifetime risk of developing cancer in that tissue in the U.S." The correlation between these parameters suggests that two-thirds of the difference in cancer risk among various tissue types can be blamed on random, or 'stochastic,' mutations in DNA occurring during stem-cell division, and only one-third on hereditary or environmental factors like smoking, the researchers conclude. 'Thus, the stochastic effects of DNA replication appear to be the major contributor to cancer in humans.'" The CBC reports: "The researchers said on Thursday random DNA mutations accumulating in various parts of the body during ordinary cell division are the prime culprits behind many cancer types. They looked at 31 cancer types and found that 22 of them, including leukemia and pancreatic, bone, testicular, ovarian and brain cancer, could be explained largely by these random mutations — essentially biological bad luck. The other nine types, including colorectal cancer, skin cancer known as basal cell carcinoma and smoking-related lung cancer, were more heavily influenced by heredity and environmental factors like risky behavior or exposure to carcinogens. Overall, they attributed 65 percent of cancer incidence to random mutations in genes that can drive cancer growth."

20 of 180 comments (clear)

  1. Re:mostly bullshit by Bengie · · Score: 5, Insightful

    I think you missed the part about 65% and not "all" cancers, and some cancers are highly affected by carcinogens and some are less based on biases created in modern living.

  2. Re:mostly bullshit by Hartree · · Score: 4, Funny

    So, you're saying you're a lawyer?

  3. actual paper by kharchenko · · Score: 5, Informative

    Here's a link to the actual paper, and a pretty nice editorial from Science (as opposed to CBC).

  4. Environmental Factors? by m00sh · · Score: 4, Informative
    The summary says,

    The correlation between these parameters suggests that two-thirds of the difference in cancer risk among various tissue types can be blamed on random, or 'stochastic,' mutations in DNA occurring during stem-cell division, and only one-third on hereditary or environmental factors like smoking, the researchers conclude.

    The article says,

    By “chance” Tomasetti meant the roll of the dice that each cell division represents, leaving aside the influence of deleterious genes or environmental factors such as smoking or exposure to radiation.

    The summary says 1/3 has smoking and environmental effects, while the article says the 1/3 doesn't have smoking and environmental effects.

    Lately, slashdot summaries have gotten worse and worse and completely change what is being claimed.

  5. Initiators vs promoters by manu0601 · · Score: 4, Interesting

    The headline is shocking when one consider the steep rise of cancer since 1945. If it was luck, then how it could change over time?

    But I think the paper could still be a valuable contribution, it is just that this summary ignores the difference between cancer initiation and cancer promotion. Many environmental factors favor existing tumors but do not create them. Hence initiation can be random, while promotion can be environment-induced.

    1. Re:Initiators vs promoters by Immerman · · Score: 3, Informative

      Indeed. I seem to recall reading something several years ago claiming that the average person develops cancer many times in their life - it's just that most of the time the tumor doesn't survive for long, or never grows beyond microscopic size. It's not the starting that's the problem, it's the conditions that allow it to grow and spread dangerously.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    2. Re:Initiators vs promoters by x0ra · · Score: 4, Informative

      The world population almost doubled since 1940 (http://en.wikipedia.org/wiki/World_population), not to mention our capacity to detect smaller and smaller tumors made the number explode. Before, people were dying, not they're dying from a diagnosed X or Y reasons. Not to mention our lifespan increased, which increased the likelihood of our body's to go AWOL.

    3. Re:Initiators vs promoters by Njorthbiatr · · Score: 3, Interesting

      The rise of cancer is related specifically to the rise of life expectancy.

      Live long enough and cancer will kill you; it's the primary obstacle in immortality.

    4. Re:Initiators vs promoters by stoploss · · Score: 5, Informative

      You seem to misunderstand: cancer requires more than a single mutation. At a bare minimum cancer needs a protooncogene mutation, and then typically also requires Knudson two-hit on at least one of the tumor suppressor genes. That, together, gets cancer started.

      The angiogenesis and metastasis mutations (among others) happen later due to natural selection. Cancer is just evolution.

      To restate: I have never heard of a single DNA point mutation from wild type that can cause cancer. Multiple mutations of specific types are required. The odds of this happening are increased because most adult cells are on "pause" in the cell cycle, so mutations can accumulate without causing immediate triggering of apoptosis.

  6. Re:mostly bullshit by Kjella · · Score: 4, Insightful

    Oh please, there are so many billions of people living wildly different life styles and there's a considerable incidence of cancer all of the world. And we got cases of cancer that are 3000 year old, it's not like it showed up recently. And if you correct for increased lifespan there's no explosion in cancer, we only have a lot more old people whose cell reproduction system has had longer to develop a critical fault. Obesity is a contributing factor to heart problem, there's still normal weight/underweight people with heart problems. I don't know any rational basis to assume the default is almost no cancer and it all must be part of some conspiracy, but apparently the tin foil hatters are modding you up. I guess they can mix the cancer-giving stuff into the chemtrails...

    --
    Live today, because you never know what tomorrow brings
  7. Sure just leave out the top two cancers. by Anonymous Coward · · Score: 3, Interesting

    Leave out the top two, by far the most common, and the remaining top two are still predominantly hereditary and or environmental.
    From: http://apps.nccd.cdc.gov/uscs/toptencancers.aspx

    Top 10 Cancer Sites: 2011, Male and Female, United States Rates per 100,000

    1. Prostate 128.3
    2. Female Breast 122.0
    3. Lung and Bronchus 61.0
    4. Colon and Rectum 39.9

    then a big drop in numbers before you see
    5. Corpus and Uterus, NOS 25.4 ...

    Me thinks somebody is playing funny buggers with the numbers to get some funding for their particular line of research, while undermining the preventative medicine message at the same time. Evil.

  8. Re:No such thing as luck, scientifically by Immerman · · Score: 3, Informative

    As I recall a great deal of effort has been spent attempting to prove the existence of "hidden variables" in Quantum Mechanics, yet to date virtually all evidence suggests that they do not exist, and that quantum-level events are truly random. What makes you think that future discoveries will fundamentally change that? Do you just not like the idea that there might be some option for choice in your life?

    --
    --- Most topics have many sides worth arguing, allow me to take one opposite you.
  9. Tripe.. by Rigel47 · · Score: 3, Informative

    Sure, anyone can get cancer no matter how healthily they live. But modern medicine is so absurdly and willfully blind to the role of nutrition that these conclusions can be largely dismissed by anyone who thinks for themselves.

    Oh, hey, trace arsenic cuts breast cancer by FIFTY PERCENT.

    What's that? Lithium in drinking water is also associated with a host of benefits? Say it ain't so..

    Gee, getting some sunshine / vitamin D can lower risk of pancreatic cancer??

    I could go on and on but what would be the point.. supplementation and the like is at best psuedo-science in the eyes of western medicine.. it's much more profitable to engage in "sick care" than to actually equip our bodies with the things it needs at some single percent of the cost.

  10. Re:mostly bullshit by fractoid · · Score: 3, Interesting

    There's a big difference between saying "most cancers are caused by random chance" and saying "there aren't specific substances that cause cancer."

    --
    Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
  11. Sorry, I believe in a just world by Anonymous Coward · · Score: 4, Funny

    I must believe that when people get cancer, it is solely due to a personal failing, like smoking, poor diet, lack of exercise, drug use or obesity. Then I can blame them personally and feel good knowing that it can't happen to me because I don't commit any of those vices. Nor should society, aka me, have to pay for their cancer through higher insurance rates or government taxes because cancer patients are simply reaping what they have sown! The made the wrong heath choices, they should face the consequences.

  12. Context matters by Okian+Warrior · · Score: 4, Insightful

    The headline is shocking when one consider the steep rise of cancer since 1945. If it was luck, then how it could change over time?

    You're forgetting the context in which the study was made.

    By assigning most cancer to random chance, they are laying the groundwork for the defense against future lawsuits for negligence and compensation against corporations. Companies will pour money into shouting these results as widely and loudly as possible, it will become a public meme, and the populist mantra will be "I got cancer, but it was just bad luck" for decades.

    This is similar to the recent history of the tobacco industry, it took over 50 years to sort that out and the damage hasn't yet settled.

    Expect this report to be wildly popular for the next few years.

  13. Re:mostly bullshit by Anonymous Coward · · Score: 3, Insightful

    Agreed. It's mostly bullshit reporting too. 65% of cancers are not caused by "bad luck". They are caused by yet unknown reasons. Unknown reasons is not "bad luck". Bad luck is getting hit by a meteor.

    http://www.medscape.com/viewar...

    In the United States, 1 in 3 cancer deaths is related to obesity, poor nutrition, or physical inactivity, and the problem will only increase as more countries and regions adopt the diet and lifestyles of more economically developed economies.

    Nearly 20% of the world's adult population smokes, and worldwide tobacco is killing around 6 million people each year from a variety of smoking-related diseases, the report estimates.

    Precise figures are given for the year 2000, when 4.38 million premature deaths globally were attributed to smoking, with causes listed as cardiovascular disease

    Still under-recognized, and not acted on, is the association between drinking alcohol and cancer.

    The IACR has labeled alcoholic beverages as "carcinogenic to humans" (and placed them in group 1, alongside ultraviolet light and chronic infection with hepatitis B). This classification was first made in 1988, and then confirmed in 2007 and 2010.

    http://www.livestrong.com/arti...

    33% is from obesity, and inactivity. 20% of the population is succeptible to smoking related cancers. In the US that is 60m people and 200k got cancer from it. And 1.6m total cancers a year. So, 12% of all cancers are tobacco.

    http://seer.cancer.gov/statfac...

    So, WTF? 100% - 33% - 12% = 55% remaining

    so *how* do you even get to 65% with just tobacco and obesity/inactivity accounting for 55% already? We haven't even accounted for external chemical factors like record usage of RoundUp alone, never mind the rest of the crap.

  14. Really bad summary. totally bogus math by chromaexcursion · · Score: 3, Informative

    It's 2/3 of all types of cancer, are random. Not 2/3 of all cases of cancer (excluding the most common ones).
    bogus math. pointless conclusion.

    There are lies
    Damn lies
    Then there are statistics

  15. Re:mostly bullshit by tinkerton · · Score: 3, Interesting

    That's all pretty muddy thinking. Suppose that all cancers are decided by a roll of a set of dice, and carcinogens and genetics merely control how many black and green faces there are on the dice. Then a cancer is never just a matter of luck or carcinogens but always both. But it's still possible to conclude that there would be 35% less cancers if we kept the carcinogens down. Or put differently, we shouldn't hope to be able to cut in half the number of cancers by just removing carcinogens, because it just doesn't have enough impact. So you have a potentially very valuable research result, but it gets interpreted in a nonsensical manner.

  16. Re:mostly bullshit by gnasher719 · · Score: 3, Insightful

    Agreed. It's mostly bullshit reporting too. 65% of cancers are not caused by "bad luck". They are caused by yet unknown reasons. Unknown reasons is not "bad luck". Bad luck is getting hit by a meteor.

    "Unknown reasons" _is_ bad luck. If there are things that I should avoid and could avoid to increase my chances of being cancer free, but nobody knows about it, then it is just bad luck if I encounter these things. If there are things that I know I should avoid but I can't avoid, that's also bad luck. Being hit by a meteor is just an extreme case of the second kind of "bad luck"; it's something I know I should avoid but I can't.