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Why are cancer rates skyrocketing ?

  1. Feb 4, 2014 #1

    "Cancer rates are expected to increase by 75% by 2030" wtf? this is horrible. Why isn't more resarch being poured into this, this is one of the biggest health hazard if not the biggest health epidemic in the future.

    Cancer is horrible and it is increasing, clearly the causes are human. Are there ANY scientific studies on why this is happening?

    let me guess, as always it's chemicals in our food, radiation from devices and pollution that is causing this. I am also guessing that we might even be aging faster because of this.

    EDIT: apparently the cause might be people living longer, or just an increased number of diagnosis, but that still doesn't neccesarily explain the increase in the 1st world.
    Last edited: Feb 4, 2014
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  3. Feb 4, 2014 #2

    D H

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    Sure it does. It's a combination of population increasing and people living longer. The "cancer rate" as measured in that article is the number of cancer cases per year. A growing population accounts for a good chunk of that increase. In the developed world, we're living longer. With many infectious diseases curable (at least for now), something else is going to bite us because we're all going to die of something. That something else is largely cancer.
  4. Feb 4, 2014 #3
    Actually these are among listed causes of the increase, it's absolutely not just population increase. Although the magnitude of which aging populations play a part is debatable

    - Smoking
    - Infections
    - Alcohol
    - Obesity and inactivity
    - Radiation, both from the sun and medical scans
    - Air pollution and other environmental factors
    - Delayed parenthood, having fewer children and not breastfeeding
  5. Feb 4, 2014 #4

    D H

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    A growing and aging population *is* the key cause of the increase. Most of the increase will come from the developing and underdeveloped worlds. People living in an area where living to fifty years of age don't have a cancer problem. They have problems with starvation, malnutrition, infectious diseases, accidents, and violence. Cancer rates rise as those causes of early death are eliminated. Cancer is much more prominent in the developed world (it is the leading cause of death in some developed countries) because cancer is a predominantly a disease of the elderly.
  6. Feb 4, 2014 #5


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    There is also recognized a genetic predisposition to developing certain cancers, that cancers run in families. Actual cancer probably doesn't manifest itself in an individual with the predisposition unless other factors are present, but it does indicate that cancer has not selected itself out of the human gene pool yet.

    You see a figure that cancer rates are expected to increase by 75%, but one must ask, what is the current actual rate of cancer diagnosis? How many people in a sample of 100,000 individuals have or will develop cancer? Obviously, if the cancer rate today is that 1 person in 100,000 has or will develop cancer, and then in the future the rate becomes 2 persons in 100,000, you can claim that the cancer rate has risen 100%.
  7. Feb 4, 2014 #6


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    It takes time for these things to cause cancer, so living longer would explain a higher incidence of cancer from these sources. Also we are better at diagnosing cancer and at an earlier stage, years ago people may have died and been given a vague or wrong diagnosis (for example - heart, kidney, liver failure, where the actual cause was cancer).

    Also, I will need you to post the medical research from an approved source for the last claim you made, I have bolded it. I have seen it mentioned, but have never see the actual studies.

    Appears it is how young the woman is that is the key.

    Last edited: Feb 4, 2014
  8. Feb 4, 2014 #7


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    Another way to look at what D.H. said:

    Everybody dies for some reason. If you eliminate a lot of causes of death, for example by having effective antibiotics and disease-free food and water supplies, the death rates from the causes you haven't eliminated will inevitably rise, to make the total add up to 100%.

    Most of the statistics from the health care "industry" never mention the inevitability of death, of course - there seems to be an unwritten assumption reducing any one cause of death is self-evidently a good objective.
  9. Feb 4, 2014 #8


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    One of the things that I have seen propounded as being a reason (albeit not an overwhelming one) is that modern diet is a contributor. I don't know any details on this and it might be wrong, I'm just dredging up something I remember reading.
  10. Feb 4, 2014 #9
    Our federal government (assuming you're US) has been pouring money into cancer research since 1922, almost a full century.

    In the 1990's, the primary NIH focus shifted from cancer research (which, in terms of treatments, had been very unproductive) to the genome project. As was no surprise to anyone, the genome project and other technologies develop during that period transformed cancer research. And since it resumed, it has had many successes.

    Currently, the National Cancer Institute annual budget of about $4.9B represents most all of the federal contribution to cancer research. Obviously, it doesn't include private research and all of what is done at teaching and research hospitals.
  11. Feb 4, 2014 #10


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    The medical news today article linked to by the OP is reporting on a study published in 2012 in the journal Lancet Oncology (Bray et al. 2012. Global cancer transitions according to the Human Development Index (2008–2030): a population-based study. Lancet Oncology 13:790. http://dx.doi.org/10.1016/S1470-2045(12)70211-5 [Broken]). The article predicts that worldwide in 2030, there will be 22.2 million new diagnoses in cancer, an increase of 75% over the 12.7 million new cases of cancer in 2008. Considering only demographic changes (population increases, people in the developing world living longer and adopting lifestyles more like developed nations), however, the predicted number of new cases of cancer is 20.3 million, a 61% increase from 2008. Therefore, the bulk of the rise in new cancer incidences is due to changing demographics across the globe.

    The authors looked at incidence of different cancers from 1988-2002 in developed nations to look for trends occurring independently of demographic factors. The authors found:
    • The incidence of stomach, cervical, and uterine cancers are decreasing at 2-5% per year.
    • The trends for lung and liver cancers are difficult to generalize (although lung cancer may be decreasing among men and increasing among women at ~ 1% per year in each case)
    • The incidence of colorectal, breast and prostate cancers are increasing at ~1-3% per year.

    The authors note that the types of cancers in decrease in developed nations are generally caused by infection whereas the types of cancers increasing in incidence are more associated with reproductive, dietary and hormonal factors (although the exact reasons for these increases and decreases are not studied in depth by this paper).
    Last edited by a moderator: May 6, 2017
  12. Feb 5, 2014 #11


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    And this is interesting. Apparantly pregnancy has a risk-benefit.

  13. Feb 6, 2014 #12


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    As others already pointed out, the increase of life expectancy is mainly responsible for the increased number of diagnosed cancer cases.
    Hence it is more interesting looking at age adjusted incidence rates which refer to a standard population of given age structure.

    For the US, there is a fantastic page where the cancer risk for all kinds of cancer can be analysed:

  14. Feb 9, 2014 #13


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    I'd weigh in with the others who discussed aging. Cancer risk is largely a function of age and/or exposure to a mutagen. Particularly in tissues that are very active throughout a person's lifetime; like the GI tract. Increased cellular turnover leads to more chances for something to go wrong.

    Also longevity has increased the age we can stay exposed to mutagens that can cause cancer. Think about smoking for example. Smoking increases your risk to develop pneumonia and pneumonia is something that used to kill people (at least in the US) a lot more often than it does now. However, with better antibiotics patients are more likely to survive. So someone who smoked and got pneumonia 70 years ago might have died, but with the improvement of care now that patient will more than likely live. Then they can, unfortunately, go back out and get back to smoking, continuing to increase their chances of lung cancer.
  15. Feb 9, 2014 #14


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    To further beat the dead horse:

    Evolution and the inevitability of human cancer.

  16. Feb 14, 2014 #15
    I'd add one add factor: measurement artefact.
    -Past data is often sketchy. When I was looking for statistical data for Poland, during early communism period, the death rate of diagnosed cancer was over 100%! (Yes, rather correct data from death certificates but only partial data for diagnosed)
    -Better diagnosis of ex. prostate cancer, quite often even without any treatment it would anyway give person enough time to die from unrelated reasons, before it had a chance to fully develop.
    Last edited by a moderator: Feb 14, 2014
  17. Feb 14, 2014 #16
    While I think this sounds a bit alarmist and somewhat of an over-reaction (It's quite easy to create a diet of organic and minimally processed foods which have very little in the way of "toxins"), and I don't think you understand what genetically modified foods are or how they are made, I would agree that in general we have been on an upward trend of adding chemicals to our foods and increasing the degree to which they are processed. Probably not a good thing.

    This is pretty ridiculous. Water is treated to get rid of these chemicals, or bring them down to basically negligible levels. Do I have any studies that show that they are harmless? No, I'm sure I could find something, but it's very difficult to do controlled experiments based on drinking water so, I'm not sure how definitive they would be. But basically we have the same argument as homeopathy. The levels of these chemicals are required to be very, very low.

    As naturally occurring rocks and elements emit radiation (especially containing radium), water distribution centers test for radiation levels in drinking water. There has always been radiation in many/most peoples' water, especially if those people use groundsource water, rather than surface water sources. Water distribution centers pass the water through processing filters which collect radium, removing it from the water.

    Hard to argue that increased airbourne chemical presence hasn't impacted our cells/dna's ability to replicate.

    Ugh, just what I thought. Read Pythagorean's post, as well as the numerous others which have pointed to the fact that cancer is an inevitable byproduct of longevity.
  18. Feb 14, 2014 #17
    Actually even that is not fully correct. The dominating cause of death from air pollution is actually indoor air pollution, which actually decreased dramatically with better house heating and cooking systems.
  19. Feb 14, 2014 #18


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    I am allowing travis' post since he has pointed out errors, but going forward, no posts presenting personal opinions will be allowed unless mainstream scientific research in an accepted journal are provided to back up your post.
    Last edited: Feb 14, 2014
  20. Feb 14, 2014 #19
    My Apologies for opinionating.
    Highly cited Drinking water contaminant study - http://m.bmb.oxfordjournals.org/content/68/1/199.full

    I wish you had Let my post stand on its own,

    As a demonstration for the forum's experts to disprove, since it was Just "personal opinion".

    In fact in that post I was synthesizing my meta-analytic research

    into the epidemiological matter of increasing cancer rates.

    In my BME classes, we studied the cancer therapies using peptide-targeted multifunctional ultra-selective nanoparticles - similar to this Chinese Team's concept --> http://phys.org/news/2014-02-cancer-drugs-hitch-smart-gold.html
    Last edited: Feb 14, 2014
  21. Feb 14, 2014 #20


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    you're new so you did not receive an infraction.

    That's actually something we do not want. I only allowed Travis's response since it was so long.

    Just remember, to cite sources, if the source is lengthy, please quote a small portion that specifically backs up your statement so that members don't have to read through an entire paper to find what you are referencing. And thank you for understanding and posting a link, we need good, knowledgeable people here. :approve:
  22. Feb 14, 2014 #21


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    Without context of your removed post, I'm not sure what your point is.

    Edit: oh, nevermind, I see it in Travis' post.
  23. Feb 14, 2014 #22
    So you deleted my post... because I haven't backed it with link to Polish statistical data? You wanted me to link a site in Polish???
  24. Feb 14, 2014 #23


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    Why not? I believe we have a moderator that could even read it. Even better, link to the associated peer review studies... there's often English versions.
  25. Feb 14, 2014 #24


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    Obviously there are many more risk factors for cancer besides age, although this is almost always the most important one.
    Having worked as a radiation epidemiologist for some time let me give some examples:
    One of the most common cancers is primary liver cancer, especially in undeveloped countries. As it is often not diagnosed correctly, it is hard to find good data on it. Anyhow we know quite a lot of high risk factors, namely infections with hepatitis b and c, and eating food containing aflatoxines. Hepatitis infections are very common in asia which makes it one of the most abundant cancers there. Aflatoxines are produced by moulds (Aspergillum flavus) growing e.g. on peanuts. This is very important in africa.

    Lung cancer: Besides smoking, the second most important risk factor is radon in homes.

    Leukemias: There, comparisons between regions and ethnics are very interesting: For example, Chronic Lymphatic Leukemia (CLL) is very rare in asians whence the increase of risk due to radiation exposure is hard to estimate from studies on survivours of atomic bombings.
    Accute Lymphocytic Leukemia (ALL) is most often diagnosed in children, so it represents a rare case of a cancer were risk decreases with age. One important risk factor is radiation, especially from CT's received in childhood.
    Also population mixing seems to lead to an increase. One suspects that some viral infections may be behind this which have only some mild fever as an accute effect, but seem to increase the leukemia risk.
    Accute Lymphatic Leukemia (AML) can be induced by exposure to several toxic chemicals, namely benzene.
    However, the benzene content of fuel has been reduced considerably.

    Stomach cancer: In Japan risks are much higher. One suspects that it has to do with diet, especially eating food conserved by salt.

    In depth information on many known carcinogens is available from the IARC (International Agency on Research on Cancer): http://monographs.iarc.fr/
    especially the series of monographs:

    Interesting is also a list substances we are exposed to, e.g. through food, and their carcinogenic potential in rodents: http://toxnet.nlm.nih.gov/cpdb/pdfs/herp.pdf

    Generally, exposure to toxic or carcinogenic substances is lower nowadays than throughout the last century, at least in developed countries. E. g. think of the ban of asbestos or leaded fuel.
  26. Feb 14, 2014 #25
    So should do a long googling to find data that would prove rather uncontroversial subject to only one person on this forum (Borek?), who has not so far even expressed interest with that topic?
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