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Comment by petersellers | Hacker News Reader

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 deaths per year from heart disease have been going down in the US since 1975 (see here: http://www.heart.org/idc/groups/heart-public/@wcm/@sop/@smd/...)

It's irritating because the article's premise is flawed. It also gives no statistical data to back the claim that cancer rates are increasing.

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Because it wants to scare you, not reassure you. If it had started, "We've been so successful in tracking down and treating the things that lead to heart disease, it may soon drop to second place leaving Cancer as the #1 cause of death." Then you would be all happy that you weren't going to die of a heart attack and realize that your risk of dying from cancer hadn't changed (actually its been going down as the cohort of major smokers leave the population). But who wants to feel good about this stuff really? :-)

Let's not get ahead of ourselves, we haven't conquered heart disease. It's not scare tactics, it's fact.

There's plenty of cognitive dissonance now that the stuff that kills us anymore is the stuff we understand the least. Actuarial tables aren't something we can reason about intuitively.

I was shocked to learn that an nMRI (where the nuclear "n" is usually silent) doesn't involve radioactivity. Such careful PR to avoid confusion about electromagnetic radiation, and it didn't even work?

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 amount of numbers and studies ends up obscuring their main point: A culture of using the “best” medical tool available instead of the “appropriate” tool can have adverse health effects, and has to stop.

All in all, there is a reason this article was filed under Opinions, not Science.

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).

The article is generally short on specifics, both numbers and citations. I wrote a letter to the editor about that and I encourage you to do likewise.

This is an important point to make. In fact US deaths from cancer are on the decline too:

> An American Cancer Society report finds steady declines in cancer death rates for the past two decades add up to a 20 percent drop in the overall risk of dying from cancer over that time period.

http://www.sciencedaily.com/releases/2014/01/140107102634.ht...

It also seems to imply that medical tests which expose us to radiation are the cause of supposedly increasing cancer rates... which _seems_ a bit alarmist?

That would actually be a sound argument: If we assume a linear damage model for radiation exposure (which is a generally accepted model for these circumstances), then there is no safe dose. Instead, any exposure increases your lifetime risk of cancer. It is therefore not useful to talk about how medical imaging causes an individual case of cancer.

But for a larger population we can figure out what the cancer risk without medical radiation exposure would be, and what the observed probability is. We can then ascribe the difference to these medical tests. Obviously there are a number of ways to fuck up this analysis. Geological differences in the natural radiation dose shouldn't be underestimated. However, almost half of the lifetime radiation dose of a human does come from medical applications, and it would certainly be good to reduce that.

Really... fixating on the risk of cancer at all is a mistake. As other commenters have said, it's about balancing the risk with the value. Instead, we should find

a) How much radiation one might on average incur due to medical reasons b) How many years of life that causes us to lose on average (or per capita) c) How many years of life the average person gains due to the use of this technology.

As long as c - b > 0 (in a real way) we don't really have a problem here. We have an optimization to make. I don't see any evidence here that c - b <= 0. I also don't see any evidence that c - b > 0. Any other point seems moot.

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