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It is nearly 50 years since Rachel Carson's Silent Spring was published where she popularised a belief that we are all being poisoned by artificial chemicals.

For the first time in the history of the world, every human being is now subjected to contact with dangerous chemicals, from the moment of conception until death.

She popularised the idea that we are suffering an epidemic of cancer. The idea has not gone away. Some randomly selected modern comment illustrates the currency of the idea. A 2008 opinion article in the New York Times proposed that "we can stop this epidemic of cancer". The London Evening Standard reports "Modern living to blame for cancer epidemic". A quick Google search will reveal the ubiquity of the assumption that we are faced with an epidemic (though there is some disagreement on the cause).

But not everyone agrees. This piece from Reason.com asks "what cancer epidemic?" and quotes an ACS report:

Overall cancer incidence and death rates have continued to decrease in men and women since the early 1990s, and the decline in overall cancer mortality has been greater in recent years...

So the common assumption is that there is an epidemic. But some solid figures don't seem to support the idea. One reason might be confusion around the statistics (for example failing to adjust for age or smoking). Who is right?

Just to be clear about the question and to avoid some possible distractions, the question is not about causes of cancer, just rates. Further, the specific question is whether cancer rates adjusted to exclude smoking (a major contributor) and to correct for age are growing significantly.

matt_black
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    This question is going to be difficult to answer, because "cancer" is not a single disease, but a broad range of problems with a broad range of causes (some even, shockingly, aren't caused by smoking!). Grouping them together as one item isn't [helpful](http://www.smbc-comics.com/index.php?db=comics&id=2438). – Oddthinking Dec 15 '11 at 00:11
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    Between longer lives overall, better control of many other common killers, better diagnoses, and [higher survival rates](http://skeptics.stackexchange.com/a/6225/782) you probably know more people who have or have had cancer than your parents did when they were your age. This kind of thing could contribute to a impression that there is more cancer about. – dmckee --- ex-moderator kitten Dec 15 '11 at 02:03
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    It seems to me that smoking (or, for that matter, standing near smokers) really ought to count as "contact with dangerous chemicals". – Jivlain Dec 15 '11 at 03:38
  • @Oddthinking I get the joke; "cure for virus" is politically grammatically incorrect. – Mateen Ulhaq Dec 15 '11 at 03:48
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    to add to dmckee's argument: in the past a lot of things we now diagnose as cancer went undiagnosed or were misdiagnosed, so historical data will show an increase in the number of cancer cases as diagnostic techniques changed. – jwenting Dec 15 '11 at 06:36
  • @muntoo: This is why humour is hard on the Internet - not knowing whether others don't get it or I'm missing their point. No, it isn't about political correctness, grammatical correctness or a blurring of the two. It is about mixing between the categories of individual diseases (potentially with cures) and broad-brush descriptions. Researchers are not looking for a "cure for cancer" and more than they are looking for a "cure for virus" or a "cure for illness". Their goals are far more tightly scoped. – Oddthinking Dec 15 '11 at 07:33
  • I realise that cancer is a broad category, but the popular belief seems to be that the broad rates of cancer are growing quickly. My own view of a good answer would address the handful of major cancer types and show whether they are growing when appropriately adjusted for demographics and smoking prevalence. The broad thrust of an answer would not be altered if the results for rare cancers were different. Some discussion of different cancer types is clearly required just to eliminate smoking related cancers. – matt_black Dec 15 '11 at 10:14
  • There are plenty of cures for virus. Many strong acids and temperature extremes have been shown to broadly destroy viruses in vitro. I'm pretty sure they'd work on cancer as well. And, of course, hard radiation! – John Rhoades Dec 15 '11 at 20:59
  • @JohnRhoades you're wrong. There are no cures for virus borne diseases at all. What you're talking about is avoiding infection, prophylaxis iow, not curing the disease. – jwenting Dec 16 '11 at 10:52
  • @jwenting No, what I was referring to was "Cures for Cancer" that work in vitro without any regard for being safely usable or even effective in vivo. And yes, all the things I listed will destroy a virus. They just happen to destroy people as well. – John Rhoades Dec 16 '11 at 14:13
  • @JohnRhoades same is true for most any cancer treatment except surgery. They're all about killing the tumor before they kill the patient. – jwenting Dec 19 '11 at 08:34
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    The reason cancer is becoming a more prevalent 'disease' is because we've gotten *really damn good* at eliminating causes of death that aren't cancer. – Shadur Mar 22 '16 at 05:15

2 Answers2

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No, there is not currently an epidemic of cancer. Instead, cancer rates appear to be holding steady over the long term while other causes of death are dropping dramatically. This appears to be the reason that cancer is now the leading cause of death in developed countries, rather than because cancer rates are rising significantly.

In searching for better historical data than the first reply, I found this paper from the Max Planck institute for Demographic Research.

Here we have an illustration showing "Annual death rates from all causes, cardiovascular disease, and cancer from 1900 to 1980 for U.S. women aged 60 - 65". This data eliminates the other usual early causes of death like childhood disease, so focuses on later-life causes of death instead. This graph shows that "other causes" has dramatically decreased since 1900 (which is expected - medical science had advanced greatly in the 20th century), that deaths from heart disease have decreased dramatically since about 1950, but cancer has continued to be largely incurable, while the rate at which we contract it has neither increased nor declined significantly.

I find these results satisfy my own criticism of the previous data as well as covering other causes of cancer that might have more to do with modern life.

Edited to add:

Statistics Canada just released a nice graph showing all causes of death since 1950. We see that around 2005, Canada's death rate due to diseases of the circulatory system has dropped below all cancers. And that all cancers has not significantly changed since 1950, although there's been a bit of a dip since about 2003.

enter image description here

Ernie
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  • It would be worth including some quotes or charts from that report to improve your answer. I suspect your conclusions are right, but good answers include the key items inside the answer to avoid imposing extra effort on readers and link rot. – matt_black Jul 05 '13 at 20:46
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No, there is not currently an epidemic of cancer. Cancer incidence rates for the last 10 years have been fairly flat.

Source - UK cancer incidence data

All Malignant Neoplasms Excluding Non-Melanoma Skin Cancer (C00-C97 excl. C44), European Age-Standardised Incidence Rates, Great Britain, 1975-2008

All Malignant Neoplasms Excluding Non-Melanoma Skin Cancer (C00-C97 excl. C44), European Age-Standardised Incidence Rates, Great Britain, 1975-2008

The European age-standardised incidences rate for all cancers in Great Britain increased by 16% in males and 34% in females during the period 1977-1979 and 2006-2008, with almost this entire rise occurring before the late 1990s.

Tom77
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    Would be interesting to see it side-by-side with live expectancy figures. – vartec Dec 15 '11 at 14:37
  • Are these adjusted for age or just for raw population? – matt_black Dec 15 '11 at 14:38
  • These are Age-Standardised – Tom77 Dec 15 '11 at 15:29
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    Can we exclude the cancers that are specifically caused by smoking? – matt_black Dec 16 '11 at 16:04
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    It would be nice to see these corrected for first-time cancer, because increased survival rate would certainly inflate the total incidence. – RomanSt Dec 19 '11 at 21:18
  • This is disingenuous, and implies that for an epidemic to exist, rates need to be *currently* rising. Since the numbers you present here do not show any years previous to when humans started introducing unnatural chemicals (usually sourced from refined oil products) into their environment, we can't compare current cancer rates with previous eras with fewer pollutants. So your evidence does not support your conclusion! – Ernie Jul 05 '13 at 18:40
  • The question asked was "whether cancer rates adjusted to exclude smoking (a major contributor) and to correct for age are growing significantly". – Tom77 Jul 08 '13 at 09:21