[kccqzy]

This is the pertinent quote:

> “Cancer screening was never really designed to increase longevity. Screenings are really designed to decrease premature deaths from cancer.” Explained another way, Dahut said, if a person’s life expectancy at birth was 80, a cancer screening may prevent their premature death at 65, but it wouldn’t necessarily mean they’d live to be 90 instead of the predicted 80.

Personally I think this is just a matter of terminology in public health not necessarily aligning with our intuitive understanding. I presume most people would think that preventing a shortening of lifespan is prolonging your life, but the article makes clear that they are different.

[Clent]

They are conflating cancer survival rates with longevity.

When has someone claimed that treating cancer would increase life expectancy above the average?

This is a dangerous article. People don't need more reasons to avoid cancer screenings.

[amanaplanacanal]

It looks like they were comparing a group that got screening vs a group that didn’t get screening. If the group that got screening didn’t live longer than the group that didn’t get screening, that seems like a lot of wasted dollars.

[throwway120385]

Life expectancy is really only one dimension of "health," and it's probably the most shallow dimension. If I'm quadriplegic and confined to a ventilator but I live to 80, that's the same in this metric as if I'm not paralyzed and able to breathe on my own until I die.

What if some people in the group that didn't get screening had fewer high-quality years? It might simply be that the last 5 years of life for people who are screened positive early on and who subsequently receive treatment is a better 5 years than the last 5 years of life for people who aren't screened positive early on and who subsequently have to undergo brutal hail mary treatments at the last minute.

[pessimizer]

> Life expectancy is really only one dimension of "health," and it's probably the most shallow dimension. If I'm quadriplegic and confined to a ventilator but I live to 80, that's the same in this metric as if I'm not paralyzed and able to breathe on my own until I die.

Claiming that there are missing elements that could possibly turn the equation in favor of screening is cause for further research and analysis. You can't just claim that they fall in your favor; some diagnostic and exploratory processes due to false positives are painful and/or dangerous in and of themselves.

> What if

"What if" is right. You can't just conjure these people into existence to justify current policies, you have to find them and do the statistics.

[throwway120385]

Given that screening is arguably benign for most people, you could argue that we continue screening while we gather more information. But you do whatever you want to do. I'm just pointing out that it's really premature to cancel all of your screenings based on the idea that it doesn't add any years to your life. That may be true, but there's more to a life than how long you live.

[idopmstuff]

> Given that screening is arguably benign for most people

You're 100% wrong here, this is not a given. Prostate cancer screenings, which are very common, can have both false positives as well as findings of cancer that is and would remain completely benign. These can both lead to unnecessary treatments that cause serious negative health effects, including incontinence and erectile dysfunction.

https://www.cdc.gov/cancer/prostate/basic_info/benefits-harm...

[vc8f6vVV]

There is another consideration:

1. You have an aggressive (i.e. non-treatable) cancer, maybe you feel slightly off, but you go on with your life, until you finally got worse and die. Or you performed screening, focus on treatment, bankrupt your family and ... die anyway,

2. You have a slow growing cancer (e.g. prostate), live your life and die of some other causes. Or you performed screening, got surgery, got tons of problems and die of myocardial infarction (yes, that's one of complications after prostate surgery).

If you read the original JAMA publication you would notice that there is a research on quality of life metric. That metric for breast cancer is higher among non-screened women.

[kirkni]

There are attempts to address this, “The quality-adjusted life year (QALY) is a generic measure of disease burden, including both the quality and the quantity of life lived. It is used in economic evaluation to assess the value of medical interventions.” See: https://en.m.wikipedia.org/wiki/Quality-adjusted_life_year

[dudeofea]

I'm going to start with one assumption that I believe is true: higher mental and physical stress will kill you faster.

If two statistical people both get cancer, one gets screened and potentially treated, and the other doesn't and they both live to 80, I would rather be the person that doesn't get treated.

A regular schedule of treatments is only better than a hail mary if you actually get more longevity from it, otherwise it's just more pain for the patient. At least with the hail mary, I only spend a short time feeling horrible before dying. This is most likely why doctors don't opt for treatment more than the average.

https://slatestarcodex.com/2013/07/17/who-by-very-slow-decay...

[DennisP]

Yes but as someone else mentioned, it's like an insurance policy. Buying insurance doesn't make you richer on average, it makes the insurance company richer. But you aren't guaranteed the average outcome, so it's still rational to get the insurance, to cover the cases where you'd otherwise have a catastrophic loss. As with gambling, it's not just about expected value. You also have to consider risk of ruin.

[pessimizer]

False positives can be debilitating or fatal.

[DennisP]

But at what rate? The study doesn't say.

[lowbloodsugar]

FTA: "Overall cancer mortality worldwide has decreased significantly, falling 33% since 1991, in part due to early detection as well as advances in treatment and declines in smoking."

[rdedev]

I think the consensus on cancer screening is stil not fully there? Came across this video by a cardiologist a long time ago

https://youtu.be/yNzQ_sLGIuA?si=fUttSVFQjsrIqc-p

I guess the main gist is that screening is not completely benign and a positive screen might lead to more interventions for what in the end could just be a benign tumor. Then there's the other point of detecting it late in life. Like treatment for cancer might not make much sense if you are already 89 years old

[haltingproblem]

This is the negative expectation part of most medical screening that most analyses miss.

- Medical screenings themselves have iatrogenic effects,

- the false positives interventions resulting from screenings have further negative effects and

- finally the true positive interventions don't necessarily prolong life.

All in all very difficult (confounding) tradeoffs that are impossible to quantify and understand especially when the cultural pressure is to do something.

[arisAlexis]

Do you really believe your third point? That most medical interventions for cancer do not prolong life? Or the word necessarily means your argument is null like "not all interventions prolong life". Yeah , we knew that already. It's never 100%.

[haltingproblem]

Sorry for the delay in responding.

I actually do and most of it based on what I have have directly experienced with what, especially older doctors, counsel their patients.

There is a lot of literature on how doctors die [1], which also drives my beliefs.

I am also influenced and how weak the statistical significance is on evidence based literature on interventions and how often the interventions are difficult to replicate.

As always, please do your own research :)

1- https://www.thehappymd.com/blog/bid/295228/how-doctors-die

[csours]

> most medical interventions for cancer do not prolong life

Specifically, medical interventions for cancer AS A RESULT of some types of screening do not prolong life.

Medical interventions for symptomatic cancer, and some types of screening, certainly do prolong life, and quality of life.

There are so many confounding factors in this it's hard to do something like a pareto breakdown, but it would certainly be interesting to see.

[NoZebra120vClip]

I'd rather die of cancer than die of chemotherapy.

[newaccount74]

A friend of mine had a pretty agressive cancer at age 16. He suffered through chemotherapy, a bone marrow transplant, and another round of chemo a year later. I think it sucked pretty bad. I visited him once in hospital, they made me wear a full body suit to prevent any infections.

But that was 20 years ago. He lives a normal life now and has a family. I'm pretty sure chemo was worth it.

[aeturnum]

Why would it be dangerous for people to avoid cancer screenings if those screenings do not impact life expectancy? You might want to know if you have cancer, but doesn't this suggest that...there's no baseline argument to suggest that all people undergo those screenings?

[arisAlexis]

They do impact life expectancy. The English language is a bit confusing to some mixed with statistics. They do not make life greater than average but they do make you closer to the average than if you die earlier.

[kazinator]

If we decrease premature deaths from any cause, particularly a common cause of premature deaths, we increase life expectancy. Or just what do the authors think life expectancy means? It's an average. Every premature death drags down average life expectancy.

If we say that cancer screening has no effect of life expectancy, that's exactly the same as saying that it doesn't prevent premature deaths.

If cancer screening effectively prevents premature deaths, but the effect on the population's life expectancy is small, that effect is the wrong thing to be focusing on, potentially resulting in a harmful takeaway message.

[LorenPechtel]

No, because we might be replacing one cause with another.

That's what they've found with PSA--it kills (via treating things that wouldn't actually have killed the patient) as many as it saves.

[kazinator]

> That's what they've found with PSA--it kills (via treating things ...)

I'm not sure what PSA you're referring to. The Prostate-Specific Antigen PSA is something secreted by the body, and not a treatment, so it can't be that one.

Are you referring to overdiagnosis (via PSA or any other screening), resulting in overtreatment?

[LorenPechtel]

PSA is also commonly used to refer to the test that measures the PSA level.

And, yes, it's treatment of things that weren't actually going to kill the patient. It's been known for quite a while that doing the test for screening produces no increase in life expectancy.

What this study is saying is that the same problem seems to apply to most other cancer screenings.

[vc8f6vVV]

You may be decreasing premature deaths from cancer but increasing premature deaths from other causes related to screening, thus you don't increase life expectancy. Read the original article in JAMA.

[teleforce]

There's only two things that are certain in this world, death and taxes - Benjamin Franklin.

The main purpose of screening for early disease or genetic condition detection regardless of the diseases or illness, cancer, heart attack, stroke, etc, is not really to prolong longevity, even though that's a wonderful side effect, but the main thing to prevent complication(s) that may arise from the late detection.

Apparently death does not incurs extra and massive medical bills, on the other hand complications will certainly do. If you connect the dots, this suddenly become a really good and plausible conspiracy theory.

It's a shame that most of the health organizations, I'm looking at you American Heart Association (AHA), are really against any form of routine screening [1],[2].

[1] American Heart Association 14-Element Screening (Maron, BJ Circulation 2014):

https://med.stanford.edu/content/dam/sm/ppc/documents/HSuper...

[2] ACC/AHA Release Recommendations For Congenital and Genetic Heart Disease Screenings in Youth:

https://www.acc.org/latest-in-cardiology/articles/2014/09/15...

[vc8f6vVV]

Just curious, have you read the original article in JAMA?

[somenameforme]

The paper [1] is more well written and clear than the CNN article. They were comparing the aggregate life expectancies of people who went through regular screenings vs those who did not, and there was near zero difference except for colorectal screenings where the difference was about 4 months of difference.

The paper is indeed presenting strong evidence that regular screenings have minimal value.

[1] - https://jamanetwork.com/journals/jamainternalmedicine/fullar...

[throwaway02sfv]

I can confirm these findings. My father, aged 63, passed away just 3 days ago because of blood cancer. He was totally fit and fine until 8 months ago when we first noticed his abnormal blood counts.

He did regular screening, nothing came up in it. When suddenly in one blood report, his counts were low that's when we did some extensive testing. Even with extensive testing, the diagnosis kept changing. From Myelofibrosis to MDS to AML to AEL.

Whole aspects around testing and related studies are very confusing. Tests are not at all accurate and testing is very expensive.

It seems like a scam when it comes to testing industry and pharma industry for such disorders. Bottomline is nothing helped in my father's case and we lost him after spending tons of money.

The fact that medical system remains such an inefficient system till date indicates to me that world leaders doesn't want to solve for health problems. It's an industry for them with lots of money. Everyone seems to be motivated to keep population seek and be subscribed to their drugs.

Sorry for the rant.

[francisofascii]

> except for colorectal screenings where the difference was about 4 months of difference

That sounds, uh, significant. So to clarify, does that mean people gain 4 months on average by getting this screening? Those who get the cancer gain years, and those that don't gain 0, so the average is 4 months?

[HWR_14]

That is how I read it.

It also makes me wonder that if some cancers are rare enough to average to 0 months (rounded down) that could still work out to a 1/500 chance of living to 80 vs 40. Long odds it matters, but big difference if it does.

[somenameforme]

They were testing for some of the most frequent cancers (breast, colorectal, lung cancer (in smokers), prostate), and measuring differences in outcomes down to the day.

[slingnow]

Think of what you're saying. If it was so bimodal that the screened people "gained years" while the ones who didn't "gained 0", then how could the average possibly be 4 months?

If we take your theory at face value, on average the screened people would have an 8 month increase.

[francisofascii]

A very simplistic hypothetical scenario could be, people who get colon cancer die an average of 6-7 years earlier than they would have. And if 5% of the population get colon cancer, then the average gain would be 4 months with screening.

[hn_throwaway_99]

Thanks for posting that. I read the article but not the paper, but I still feel like this may be a case where scientists "treat all time equally" in a way that most people do not, resulting in differing conclusions even though the data is the same.

That is, putting aside monetary costs for the moment (which I know is not a good idea in reality, but want to focus on another issue), you often hear about how false positives cause "added anxiety and unnecessary treatments, which can cause harm", but if a breast cancer screening saves, say, lets one woman live until 80 instead of dying at 40, how many other people's "added anxiety" would it take to say "OK, that test was worth it". I think a lot of folks would go think that saving that life should be valued a lot more than just, say, comparing 40 years for her vs. time/anxiety "wasted" for false positives.

[vc8f6vVV]

X-ray is not just adding anxiety, it's harmful, and it's affecting all women who get screening, not only those who actually get cancer. Magic of numbers.

[glimshe]

If we are avoiding premature deaths for a subset of the population, wouldn't that by definition increase average life expectancy?

[raverbashing]

Then the way this is being divulged is absolutely a very bad way

Yes, life expectancy should count premature deaths

Saying it "doesn't extend live" goes against that, because it absolutely does increase life expectancy

Science communication is bad

[ekanes]

So they increase your lifespan probabilistically, but not in any terms you can measure. That said, the article's points about the costs of screening is valid and interesting. False negatives, false positives, time and money, those are absolutely real costs and worth taking into account.

[vc8f6vVV]

Have you read the original article, not the CNN interpretation? They are talking about harm vs benefits of screening. In simple words: you performed colonoscopy, got colon perforation and died of complications. Was colon cancer prevented? Absolutely! You didn't die of colon cancer! Is it any easier? No, it's not. The chance of dying of breast cancer is around 2.5%, so 1 women in 39 will die from that. OTOH annual X-rays affect the other 38 too, how many of them will die from X-ray exposure (which can cause e.g. another type of cancer, not necessary breast)? For the sake of discussion let's say 1 in 380. Congratulations, you've just increased breast cancer related death by 10%! Only it won't be in statistic as deaths from breast cancer.

[orblivion]

I mean, you could interpret that as "most cancer screenings don't extend life, because they come back negative". It's the "not most" case you're testing for in the first place.

[pessimizer]

Not all positive tests are cancer. In some cases, actual cancers could be a tiny minority of positive tests. The tests themselves are a dangerous tool, and the way we minimize that danger is through statistics.

[kccqzy]

Then you are just changing one form of bad communication with another form. When a test indicates that there is cancer, the physician is not supposed to say "you have cancer" but rather "there is X% probability that you have cancer." If the test comes back negative, it should be "there is Y% probability that you have cancer" where presumably Y<X.