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We Are Giving Ourselves Cancer

nytimes.com

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Re: We Are Giving Ourselves Cancer

#81

Post by throwaway_yy2Di »

latk wrote: post #13
petersellers wrote: post #6

The article's first sentence annoys me right off the bat: "Despite great strides in prevention and treatment, cancer rates remain stubbornly high and may soon surpass heart disease as the leading cause of death in the United States." This seems to be implying that cancer death rates are growing and will soon "surpass" those of heart disease. While the article is technically correct, this is due to the fact that death…

Indeed. I would also like to see that British study that claims a link between CTs and leukemia – I smell selection bias. It is however true that a CT does imply a significant radiation dose. This article is especially frustrating in that the authors seem to be doctors in the appropriate fields. I assume they just went too far in dumbing down the matter, which together with their source-less references to a dazzling…

Must be this:

http://www.cancer.gov/newscenter/newsfromnci/2012/CTpediatri...

http://www.thelancet.com/journals/lancet/article/PIIS0140-67...

Note the large difference in presentation. NCI:

"...a small increased risk of leukemia and brain tumors..."

"...The researchers emphasize... the benefits of clinically appropriate CT scans should outweigh future cancer risks"

NY Times:

"...three times more likely to develop leukemia and brain cancer"

"...distressingly little evidence of better health outcomes"

It's some sort of golden rule of sensationalism: if the risk is minuscule, report it as a large multiplier over a tiny baseline.

(Or possibly, an absolute incidence count out of a gigantically large population. NYT, thoughtfully, did both).

Re: We Are Giving Ourselves Cancer

#82

Post by pbreit »

beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

Basically the first two pages I found after Googling for about a minute:

The average annual cosmic radiation dose for flight personnel was 2.19 mSv (ie, less than one CT scan) http://www.hps.org/publicinformation/ate/faqs/commercialflig...

Flight attendants 2x-5x higher cancer rates http://www.webmd.com/breast-cancer/news/20031021/flight-crew...

Re: We Are Giving Ourselves Cancer

#83

Post by rosser »

canttestthis wrote: post #78
beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

I don't know much about medicine and radiation, but is intensity a factor? Could getting x amount of radiation in 60 seconds be a bigger danger than the same amount of radiation spread out over days or months?

Yes, it can, and often is. Consider Albert Stevens. [1] He was (without his knowledge or consent) injected with a dose of 131 kBq of Pu, yielding a lifetime exposure of around 64 Sv. (An acute dose of >= 5 Sv is usually fatal.)

He died of heart disease 20 years later.

[1] https://en.wikipedia.org/wiki/Albert_Stevens

Re: We Are Giving Ourselves Cancer

#84

Post by hawkharris »

beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

While your comment as a whole is thoughtful and well written, I'm surprised to hear you say, "Medical imaging is not done very often..."

Medical imaging is commonly overused, and its overuse is recognized as being one of the leading causes of certain types of cancer. For example, the original story explains...

"In a 2011 report sponsored by Susan G. Komen, the Institute of Medicine concluded that radiation from medical imaging, and hormone therapy, the use of which has substantially declined in the last decade, were the leading environmental causes of breast cancer, and advised that women reduce their exposure to unnecessary CT scans." (The substantial decline refers to hormonal therapy, not imaging.)

Re: We Are Giving Ourselves Cancer

#85

Post by hawkharris »

beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

While your comment as a whole is thoughtful and well written, I'm surprised to hear you say, "Medical imaging is not done very often..."

Medical imaging is commonly overused, and its overuse is recognized as being one of the leading causes of certain types of cancer. For example, the original story explains...

"In a 2011 report sponsored by Susan G. Komen, the Institute of Medicine concluded that radiation from medical imaging, and hormone therapy, the use of which has substantially declined in the last decade, were the leading environmental causes of breast cancer, and advised that women reduce their exposure to unnecessary CT scans." (The substantial decline refers to hormonal therapy, not imaging.)

Re: We Are Giving Ourselves Cancer

#86

Post by slacka »

beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

As someone now in Hong Kong about to fly back home to SF, I have always tried to schedule my flights so that I minimize my exposure to day time radiation. I guess I'm in the minority, but it's something to consider when taking international flights.

Re: We Are Giving Ourselves Cancer

#87

Post by beloch »

canttestthis wrote: post #78
beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

I don't know much about medicine and radiation, but is intensity a factor? Could getting x amount of radiation in 60 seconds be a bigger danger than the same amount of radiation spread out over days or months?

I'm not a doctor, but the way I understand it cumulative exposure is what really matters.

Ionizing radiation, such as X-Rays, tends to pass through matter with less interaction than lower energy EMR, such as light. Obviously, there is some interaction or it wouldn't be good for imaging! When ionizing radiation is absorbed it (as the name suggests) ionizes an atom by knocking an electron free. That ion will then probably form a bond almost immediately, altering the molecule it's a part of. If that molecule is a cell-wall, piece of enamel on your teeth, etc. the change will be harmless. There's a small chance it could be change to the DNA of one of your cells though. Most changes are probably harmless, but some can cause the cell to replicate out of control. i.e. Cancer.

Basically, getting cancer is like winning the lottery, and radiation gives you tickets. It doesn't matter if you get them all at once or spread them out. You might think radiation sickness is evidence that acute exposure behaves differently, but it actually takes several centuries worth of background radiation exposure to induce mild radiation sickness, so you're already operating in a whole new ballpark.

Re: We Are Giving Ourselves Cancer

#88

Post by [deleted] »

hawkharris wrote: post #84
beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

While your comment as a whole is thoughtful and well written, I'm surprised to hear you say, "Medical imaging is not done very often..." Medical imaging is commonly overused, and its overuse is recognized as being one of the leading causes of certain types of cancer. For example, the original story explains... "In a 2011 report sponsored by Susan G. Komen, the Institute of Medicine concluded that radiation from medic…

[deleted]

Re: We Are Giving Ourselves Cancer

#89

Post by rdl »

a8da6b0c91d wrote: post #80
rdl wrote: post #73

When I worked with radiologists (at a PACS vendor, mainly selling to the military and the federal prisons), the radiologists and staff were exercising due care about minimizing radiation exposure from CTs. Personally, I don't care about regular x-rays, particularly digital ones, for any reasonable medical use. I get one every year or two as part of a checkup. CT and C-arm fluoroscopy scare me, as an educated person w…

Apparently loads of dentists lost fingers and hands to cancer and bone degeneration before they figured out not to hold the x-ray film themselves. Now they have the patient hold it. It just drives home that the stuff is not harmless.

I want one of these: http://en.wikipedia.org/wiki/Shoe-fitting_fluoroscope

Re: We Are Giving Ourselves Cancer

#90

Post by a8da6b0c91d »

slacka wrote: post #86
beloch wrote: post #74

CT Scan doses vary wildly depending on the type of X-ray (chest, head, limb, etc.), the size of the person, and a lot of other things. The bigger the cross-section of the thing you put in a scanner, the greater the exposure. CT machines themselves also vary considerably. Newer machines are often more sensitive and employ better imaging software, so they can do their job while delivering a much smaller dose. Anyone wh…

As someone now in Hong Kong about to fly back home to SF, I have always tried to schedule my flights so that I minimize my exposure to day time radiation. I guess I'm in the minority, but it's something to consider when taking international flights.

Some claim that wifi and cell phone emissions bouncing around in the cabin are also cause for concern. I've no idea if it's true, but I can imagine that inside an aluminum tube 150 wifi cards trying to connect might have some biological effect.
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