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We Are Giving Ourselves Cancer

nytimes.com

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Re: We Are Giving Ourselves Cancer

#61

Post by 300bps »

DenisM wrote: post #3

>A single CT scan exposes a patient to the amount of radiation that epidemiologic evidence shows can be cancer-causing That does not look right to me. A single CT scan is 2-7 millisieverts, and exposures under 13 can not be linked to health effects - look for UNSCEAR in http://en.m.wikipedia.org/wiki/Sievert If you do the math by ICRP formulae, you end up with increase chance of cancer of 1 in 2600 over the next 20 y…

The article is terrible and you've done a good job of explaining why. But there are two ways to look at this:

1. From an individual's perspective

2. From society's perspective

Let's make up some numbers for illustration. If getting a CT scan gives someone 0.01% chance of getting cancer, the risk to any individual is negligible. But to society, that means 100 extra cases of cancer.

Re: We Are Giving Ourselves Cancer

#63

Post by DenisM »

yetanotherphd wrote: post #46
DenisM wrote: post #3

>A single CT scan exposes a patient to the amount of radiation that epidemiologic evidence shows can be cancer-causing That does not look right to me. A single CT scan is 2-7 millisieverts, and exposures under 13 can not be linked to health effects - look for UNSCEAR in http://en.m.wikipedia.org/wiki/Sievert If you do the math by ICRP formulae, you end up with increase chance of cancer of 1 in 2600 over the next 20 y…

>If you do the math by ICRP formulae, you end up with increase chance of cancer of 1 in 2600 over the next 20 years from a single 7ms CT scan today. This compares favorably with "natural" risk that is 1 in 10 without any extra exposure above background radiation. But that is a meaningless comparison. The doctor should be comparing this additional risk, to the benefit of the scan. The "natural" risk of developing canc…

I see your point.

I wonder though if there should be a cutoff somewhere, below which you stop caring? I used background cancer rates as an anchor to judge if the cutoff has been reached, without getting specific about benefits of treatment in each particular case. Would you suggest another cutoff level that is broadly applicable?

Re: We Are Giving Ourselves Cancer

#64

Post by bradleyjg »

refurb wrote: post #2

I have no doubt that patients are getting exposed to more radiation via imaging than they need to. However, every decision in medicine is (or should be) a risk-vs-benefit analysis. Cancer is not the only thing you can die from. If you suffer a head injury and end up in the ER and get a CT scan, you may increase your long-term risk of cancer, but you are also drastically reducing the risk of dying from a brain hemorrh…

The doctors are doing a risk/benefit analysis: the risk is to the patient and the benefit is to their wallets. It's a no brainer.

Everyone likes to shit on lawyers, but US doctors routinely take on, and fail to disclose, conflicts of interest that would get a lawyer disbarred in a heartbeat.

Re: We Are Giving Ourselves Cancer

#65

Post by userbinator »

300bps wrote: post #61
DenisM wrote: post #3

>A single CT scan exposes a patient to the amount of radiation that epidemiologic evidence shows can be cancer-causing That does not look right to me. A single CT scan is 2-7 millisieverts, and exposures under 13 can not be linked to health effects - look for UNSCEAR in http://en.m.wikipedia.org/wiki/Sievert If you do the math by ICRP formulae, you end up with increase chance of cancer of 1 in 2600 over the next 20 y…

The article is terrible and you've done a good job of explaining why. But there are two ways to look at this: 1. From an individual's perspective 2. From society's perspective Let's make up some numbers for illustration. If getting a CT scan gives someone 0.01% chance of getting cancer, the risk to any individual is negligible. But to society, that means 100 extra cases of cancer.

100 extra cases of cancer out of how many already...? Yes, it's negligible either way.

Re: We Are Giving Ourselves Cancer

#67

Post by leoc »

DenisM wrote: post #3

>A single CT scan exposes a patient to the amount of radiation that epidemiologic evidence shows can be cancer-causing That does not look right to me. A single CT scan is 2-7 millisieverts, and exposures under 13 can not be linked to health effects - look for UNSCEAR in http://en.m.wikipedia.org/wiki/Sievert If you do the math by ICRP formulae, you end up with increase chance of cancer of 1 in 2600 over the next 20 y…

Interestingly Stewart Brand was out this year arguing http://edge.org/response-detail/25392 against of the the Linear No-Threshold model of radiation risk:

"The "Linear" part of the LNT is true and well documented. Based on long-term studies of survivors of the atomic bombs in Japan and of nuclear industry workers, the incidence of eventual cancer increases with increasing exposure to radiation at levels above 100 millisieverts/year. The effect is linear. Below 100 millisieverts/year, however, no increased cancer incidence has been detected, either because it doesn't exist or because the numbers are so low that any signal gets lost in the epidemiological noise."

IDK if his case if convincing or not. In any case, even if say 10, 50 or 100 millisieverts a year is something the human body can shrug off with no increase in risk, I imagine that might not apply to 10-30 millisieverts delivered in a very short interval of time.

Re: We Are Giving Ourselves Cancer

#68

Post by squirejons »

since the media is now exposing this secret there must have already been a decline in CT scans, otherwise the media would never say a word about it. The media never exposes a mainstream money making scam until the money has gone out of it.

Re: We Are Giving Ourselves Cancer

#69

Post by mbreese »

97s wrote: post #25

I am a surviving AML patient, relapsed once and had a stim cell donor. I have had over 50-60 CT scans and I have one or two a month to monitor my lungs for fluids. This article makes me chuckle cause who knows what it's doing to me, but without the CT scans to spot pneumonia and other infections in my lungs I would probably have died already.

Congrats on surviving AML.

I have a few oncologist friends. I think that their point of view is that once you go to see them, getting a CT or 50 is the least of your problems. So, if they even think there is something wrong, you're getting a CT. The risk of having a problem now is much worse than the remote risk of something else going wrong in the future. If you survive this bout, who cares about the extra radiation exposure.

Being able to worry about that later is a good problem to have.

Re: We Are Giving Ourselves Cancer

#70

Post by novaleaf »

pedalpete wrote: post #60
Zigurd wrote: post #8

Earlier quoted context omitted.

> Now if you do a scan every year for the next 20 years your chances go up to 1 in 130 Unless the article is wrong about the number of CT scans many people are getting, that's going to result is a huge number of avoidable cancer cases.

I'm not very good at math, but I'm reading that as a 0.7% increase in your chance of getting cancer. From 'Physics for Future Presidents', they say it is commonly accepted that we have a 20% chance of DYING from cancer before calculating for outside influences. http://books.google.com.au/books?id=6DBnS2g-KrQC&pg=PA98&lpg... Let's say the average person does not get a CT scan every year for 20 years, but rather gets 5…

that's an extra 0.7% for you. For a population of 300m (about the pop of the usa) that'd be an extra 2.1m people getting cancer.
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