Cancer man-made or junk science?

[ViewsofMars]

In their Nature Cancer Reviews article, David and Zimmerman examine ancient societies to determine the prevalence of cancer in ancient societies. They find that cancer is rare in the ancient societies that they studied and, after considering various possible explanations for the relative lack of ancient tumors, suggest that their findings provide evidence that cancers are caused primarily by factors of modern society such as smoking and pollution.

I presented this earlier :

Nature Reviews Cancer 10, 728-733 (October 2010) | doi:10.1038/nrc2914

Cancer: an old disease, a new disease or something in between?
A. Rosalie David & Michael R. Zimmerman

Abstract
In industrialized societies, cancer is second only to cardiovascular disease as a cause of death. The history of this disorder has the potential to improve our understanding of disease prevention, aetiology, pathogenesis and treatment. A striking rarity of malignancies in ancient physical remains might indicate that cancer was rare in antiquity, and so poses questions about the role of carcinogenic environmental factors in modern societies. Although the rarity of cancer in antiquity remains undisputed, the first published histological diagnosis of cancer in an Egyptian mummy demonstrates that new evidence is still forthcoming.
http://www.nature.com/nrc/journal/v10/n10/full/nrc2914.html

I would like to make it clear that "new evidence is still forthcoming". Ygggdrasil, I would like a link (url) and the statement the authors made that prompted this remark of yours, "suggest that their findings provide evidence that cancers are caused primarily by factors of modern society such as smoking and pollution." Basically, give me a quote and the link (url) that supports your claim.

Thanks for finding this. Her statement that "there is nothing in nature that can cause cancer." is so wrong. They've lost all credibility for me.

Evo, my post #26 needs to be reviewed again. I think you have to read the entire document to get the jest of what she meant. I wouldn't like to quote-mine from the article. I'll present the link once again to this message of mine.
http://www.manchester.ac.uk/aboutus/news/display/?id=6243

Personally, I'm not fond of knocking down reputable scientists in public forums. Often times, it sends a message out to individuals that scientists can't be trusted or lie. I do think Rosalie David & Michael R. Zimmerman are reputable scientists since there article did appear in Nature, which is peer-reviewed journal.

I'll make it very clear that the reason why I joined PhysicsForums was to support the scientific community. Thank you.

 

[Evo]

I'll make it very clear that the reason why I joined PhysicsForums was to support the scientific community. Thank you.

I also fully support science, but unless the statements they made (that I pointed out) in the Nature article are blatant misquotes, I can't support it. People need to know that there is a difference between good and bad science.

 

[Evo]

Claims that cancer is only a "modern, man-made disease' are false and misleading.

We were concerned to see headlines in the media today claiming that scientists say cancer is ‘purely man-made’. This is not only scientifically incorrect, but misleading to the public and cancer patients.

Our lifestyles have a great impact on our chances of developing cancer – as we’ve said many times. But the evidence that’s being used to justify these latest headlines doesn’t in any way support the assertion that cancer is modern or man-made.

The source of the story

The story is based on this press release publicising an opinion piece in the scientific journal Nature Reviews Cancer by Professor Rosalie David and Professor Michael Zimmerman.

According to the press release, the paper was presented at a conference

http://scienceblog.cancerresearchuk...n-man-made-disease’-are-false-and-misleading/

 

[Ygggdrasil]

I presented this earlier

Yes, this review paper from Nature Reviews Cancer is the one referenced by the MSN article in the opening post and the one I discussed in my earlier post. I read through the entire paper and, in my post #36, I summarized the authors' arguments and offered my own scientific critique of their arguments.

I would like to make it clear that "new evidence is still forthcoming". Ygggdrasil, I would like a link (url) and the statement the authors made that prompted this remark of yours, "suggest that their findings provide evidence that cancers are caused primarily by factors of modern society such as smoking and pollution." Basically, give me a quote and the link (url) that supports your claim.

Sure. Here is a direct quote from paragraph 18 of the Nat. Rev. Cancer review paper:

"Although the palaeopathological diagnosis of cancer is subject to many difficulties, we propose that the minimal diagnostic evidence for cancer in ancient remains indicates the rarity of the disease in antiquity. Carcinogenic environmental factors have been linked to up to 75% of human cancer, and the rarity of cancer in antiquity suggests that such factors are limited to societies that are affected by modern lifestyle issues such as tobacco use and pollution resulting from industrialization."​

The link is http://www.nature.com/nrc/journal/v10/n10/full/nrc2914.html although you need a subscription to the journal in order to be able to read the full article.

Evo, my post #26 needs to be reviewed again. I think you have to read the entire document to get the jest of what she meant. I wouldn't like to quote-mine from the article. I'll present the link once again to this message of mine.
http://www.manchester.ac.uk/aboutus/news/display/?id=6243

I agree, reading the full Nature Reviews Cancer article is necessary to understand the authors' arguments. Reading the full article let's you appreciate the fact that while David tells the popular press that "there is nothing in the natural environment that can cause cancer," such statements are absent from her peer-reviewed paper. Instead, the authors state their case much more cautiously. From the concluding paragraph:

"Despite the fact that other explanations, such as inadequate techniques of disease diagnosis, cannot be ruled out, the rarity of malignancies in antiquity is strongly suggested by the available palaeopathological and literary evidence. This might be related to the prevalence of carcinogens in modern societies."​

Personally, I'm not fond of knocking down reputable scientists in public forums. Often times, it sends a message out to individuals that scientists can't be trusted or lie. I do think Rosalie David & Michael R. Zimmerman are reputable scientists since there article did appear in Nature, which is peer-reviewed journal.

I'll make it very clear that the reason why I joined PhysicsForums was to support the scientific community. Thank you.

A small correction, the article did not appear in Nature, but in Nature Reviews Cancer, a journal published by the Nature Publishing Group. While still a prestigious, peer-reviewed journal, Nat. Rev. Cancer is nowhere near as prestigious as Nature.

Although overall the peer-reviewed scientific literature is fairly trustworthy, there are many cases where scientists overinterpret their data and make faulty conclusions. I believe this is the case with David and Zimmerman's Nat. Rev. Cancer article. From the data and arguments they present in their article, I do not believe that we can make any solid conclusions about the prevalence of cancer in ancient societies. Furthermore, if the goal is to argue that most cancers are from man-made sources, there are much more productive avenues of research to address this question.

Science advances because scientists are willing to question and criticize others ideas. Therefore, well reasoned, evidence-based criticism of published and unpublished science is a great way to support the advancement of science.

 

[bobze]

Good post Yggg.

ViewsofMars--I applaud your effort to support the scientific community, but please remember that scientists are people too and are also prone to excitement and exaggeration of their conclusions (especially in press conferences) as any "layman".

After sitting down and reading the paper there are many problems I see in it as well. You should really read Yggg's critique of it. In science we're not taught to accept something because "its published in a peer-reviewed" journal, one should read all journals with a sense of healthy skepticism. Critical thinking and skepticism are required even for "published" material. Something doesn't enter the realm of dogma simply because someone was able to get it published.

For instance in the article they authors claim;

Osteosarcoma is not currently an exceptionally rare tumour and, as it usually produces bone, one might expect to encounter it more frequently in archaeological material than is the case, especially as this is a tumour associated with young people. Bone is notorious for trapping radioactive minerals, and one can speculate about the role of radiation in our modern world in causing bone tumours.

Not exceptionally rare? The office of rare diseases over at NIH lists the prevalence as affecting less than 200,000 Americans. Or less than 0.06% of the US population. That's pretty exceptionally rare in my opinion.

Much of their conclusions are based on excerpts like this;

Gray specifically noted the total absence of any radiological evidence of malignancy in his survey of 133 mummies.

Extremely small sample sizes, biases (yes, they have a clear case of http://en.wikipedia.org/wiki/Selection_bias" (I'd like to give them the benefit of the doubt, that this wasn't their motivation for not doing statistical tests) make this paper's scientific value about worth its weight in paper.

Also I'd draw you attention to this being published under: Perspectives>Science and society. While this is still "peer-reviewed" this isn't primary research, its a glorified Op-Ed.

I think the problem is;

1. The media will pick up anything "published" in a "peer-reviewed" journal and run with it, especially when its an "something causes cancer" or "something 'cures' cancer" type.
2. People shouldn't use the media as a source for their "scientific literacy", you're getting filtered and biased information.
3. Many people aren't familiar with how scientific publication works (sure you learn about peer-review in school, but you don't delve into differences in "Op-Ed" type papers and primary research).

 

[Dr Lots-o'watts]

"Is the common nature of cancer worldwide purely a man-made phenomenon?"

The cancer-causing agents have always been there. Cancer happens when man meets the agent.

No unprotected organism lives in the scorching desert sun, no organism lives inside mineral and radioactive rocks, and no organism feed on burnt matter. But we humans, we go right at it. Man doesn't "make" the agents, man dives into them. That's the phenomenon.

 

[turbo]

Thanks for finding this. Her statement that "there is nothing in nature that can cause cancer." is so wrong. They've lost all credibility for me.

I would have to take exception to that sweeping claim, too. Years ago, I visited a rock and gem shop in Western Maine, and was chatting with the owners. A week or so before, a customer wanted to try out a geiger counter hands-on before buying, and he was wandering about the shop looking at the readings when the probe was in proximity to some minerals that tend to be somewhat radioactive. Suddenly, the count shot up and the meter was blipping like crazy. The owners and the customer tried to find out what was causing the spike, and discovered that a newly-excavated large smoky quartz crystal they had recently bought from a prospector was really hot (in the radioactive sense). If radiation can be implicated in the causation of cancers, it should be evident that natural sources of radiation need to be considered.

Of course, if you live around here and have quartz/granite underlying your prospective house, you would be well-advised to have a Radon screening preformed before buying it, so you can find out if the levels are safe or at least can be remediated.

 

[Evo]

Wow, could this thread be any more off topic? It was about cancer in mummies.

 

[Proton Soup]

Wow, could this thread be any more off topic? It was about cancer in mummies.

sorry. but i did do my best initially by referencing Galen.

 

[Evo]

I have spilt off the posts discussing various foods and health related issues.

The discussion has been moved here - https://www.physicsforums.com/showthread.php?t=441543

Only posts concerning the article on mummies in the OP will be allowed in this thread.