I had a CT scan of a fracture taken when I was a child, and doctors coincidentally discovered a tumour. My mum discovered she had breast cancer through a routine mammogram. Early detection of growths is great because it saves lives and lets patients get treatment when it's more effective.
The framing of expanded early detection as "Silicon Valley's quest to live forever" seems uncharitable.
> I had a CT scan of a fracture taken when I was a child, and doctors coincidentally discovered a tumour.
> My mum discovered she had breast cancer through a routine mammogram.
These two are not the same thing. We do mammograms, and only in women over a certain age, because they're a high risk population.
CT scans, especially chest CT scans, expose you to huge amounts of radiation. The odds that you randomly stumble on a super low-incidence tumor is dwarfed by the fact you're exposing people - especially children in your case - to large doses of ionizing radiation.
A chest CT scan smacks you with 7 mSv which is about the same as spending an hour at Chernobyl, or 7X the EPA annual dose limit for radiation exposure. [1]
Lest we not forget Bayes theorem. We only do tests on people who are likely to have the condition otherwise the risks associated with a false positive outweigh the benefits of early detection.
I'm not suggesting that, at all. I just don't like the framing that any new screening process must be part of a "quest to live forever" instead of a quest to e.g. live long enough to go to your kid's wedding.
I think the point is more that rich tech folks (like many people) think doing more testing must be good even if there's no scientific evidence to support that conclusion - the difference is rich tech folks can afford it anyways, and they're going to be very loud about it.
strken gave examples of early detection being advantegeous. The article's about MRIs. So what's the radiation risk with MRIs? If there's no radiation risk, what's the problem?
What nobody has suggested is that "rich tech folks" are having lots of x-rays in a quest for early detection.
(This is poorly phrased on my part, btw - not trying to attack you, trying to show a chain of logical thought).
> We do mammograms, and only in women over a certain age, because they're a high risk population.
raises hand I'm a cis male who had to go for a mammogram (got some weird looks in the waiting room). It's not just for cancer screening high risk women.
Normal yearly background radiation is 4 mSv. US radiation workers have a yearly limit of 50 mSv.
Never get more radiation exposure that you need to but also the EPA numbers are in addition to normal, basically unpreventable, exposure. 7 mSv is not 7x the total.
I’ve seen people bring up the whole “increased false positive rate” which is totally understandable but I don’t get how this couldn’t be a potential preventative diagnostic tool to be combined with annual physicals. Eg that unless something is obviously wrong you wouldn’t action based on any findings from a full body scan; instead you would retain the record and repeat the scan 12-24 months later. Compare anything notable for growth or other irregular change, rinse and repeat. I would imagine that would greatly decrease the amount of pointless imaging and biopsy done. There would certainly still be some done but is that not the case now?
I would imagine this is downplayed because us insurance companies are generally not huge fans of expensive preventative care procedures with little evidence base (and to the last point, fair). And additionally I’d imagine physicians and radiologists have some worry about the potential liability of things being incorrectly being labeled as benign or to be monitored and turning into malpractice claims.
So the evidence base gets established by rich people who can afford to cut insurance out of the equation and hire physicians that are open to these kinds of procedures. Unfair and something I’ll be very bitter about if I ever die of a cancer that could have been detected earlier if I was lucky enough to get imaged in the area for whatever reason.
> I would imagine this is downplayed because us insurance companies are generally not huge fans of expensive preventative care procedures...
Sure this but also: the evidence does exist and it will be a huge expensive, inconvenience, and maybe dangerous unnecessary tests/surgery for >90% of the population. Really someone has to do the math to determine the inflection point; X% of people will get some early cancer/positive result found early, Y% will get a false-positive and undergo expensive and unnecessary procedures, and Z% will still get a false result but have cost some amount of money and time.
From a public health perspective, this is unlikely to be the best-next-thing because so many people die from more preventable diseases/things or lack access to health care at all. Is it a obvious service for the upper class in SF? Certainly, because the market thinks they are 5-30x more valuable than the average person so 2.5k is nothing to be extra certain of their survival.
Does that sound weirdly dystopian? Sure, but it is just moving your chance of living (for the next year as our unit) by 0.00001% or less. Most people would not spend 2.5k on a 1/100k outcome.
> Eg that unless something is obviously wrong you wouldn’t action based on any findings from a full body scan; instead you would retain the record and repeat the scan 12-24 months later. Compare anything notable for growth or other irregular change, rinse and repeat. I would imagine that would greatly decrease the amount of pointless imaging and biopsy done. There would certainly still be some done but is that not the case now?
The problem is birds vs rabbits vs turtles (I didn't invent this; it's a classic metaphor [1]).
For any given finding on an MRI, they're going to be, tautologically, in one of three categories, in descending order of frequency:
* turtles (i.e. slow growth tumors). Most people of a certain age have them, and they'll never be an issue. MRIs will find them. You can't know they're turtles.
* rabbits (faster-growth, non-metastasized tumors). Maybe we can catch these, because they're slower than birds, and maybe can make a difference. Everyone wants to believe they're finding rabbits, but just because of the nature of the distribution, they're most likely finding turtles.
* birds (i.e. fast metastasizing tumors; think days or weeks). This is what you want to catch, because they're metastasizing. They're deadly. They're rare. You'd like to catch these before they fly away, but how often are you going to run an MRI? Daily?
Asymptomatic screening almost always catches turtles, sometimes catches rabbits, and rarely catches birds. You can't tell the difference from a single scan...so when do you choose to go further? At what cost?
I included that third link -- even though it's from the Daily Beast -- because it really drives home the practical implications of the metaphor. Consider this:
> In 2012, Archie Bleyer and Gilbert Welch published a study in the New England Journal of Medicine titled, “Effect of Three Decades of Screening Mammography on Breast-Cancer Incidence.” They found that, with the advent of screening mammographies, the incidence of breast cancer in the U.S. had doubled. For every 100,000 women screened, the number of women diagnosed with breast cancer had increased from 112 to 234. At the same time, the number of women presenting with late-stage breast cancer (the kind that often results in death), decreased from 102 to 94 (per 100,000). In other words, only eight of the 122 women diagnosed with breast cancer appeared to benefit from the screening. Eight. The others had been treated with mastectomy, radiation therapy, and chemotherapy without clear benefit.
This is a common story in the world of cancer diagnostics.
I find it plausible that it's often a good idea in medicine to be conservative before launching interventions that may have adverse side effects, but have difficulty swallowing the idea that this conservatism should be implemented by reducing visibility (eg by not applying tests too broadly if they have a nontrivial false positive rate and the condition is rare). It seems like the right thing to do would be to maximize visibility, but then to try to corroborate and not overreact to apparent positives.
> It seems like the right thing to do would be to maximize visibility, but then to try to corroborate and not overreact to apparent positives.
Far easier said than done. What actually happens when you get caught in one of these screening programs, is that you're suddenly in a universe of "continuous monitoring"...because they're trying to find the birds, and reason that since they looked at you once, they need to look at you more intensely than before.
Anyone who has ever had a mole biopsied for skin cancer will be familiar with this. They'll just keep looking for stuff, until you tell them to stop. If you get a positive, it's even worse. Everyone is acting with good intentions. It's just impossible to know the right answer, so the emergent behavior of the system is to harm people.
Isn't there a saying that the benefits of regular checkup are a myth? Since they lead to over intervention or something? I know some places encourage regular health checkups whilst other places actually actively say it's a bad idea. Any doctor can chime in on this?
Take a look at individual tests to see if they make sense.
A PSA urine test, for example, is insanely cheap and catches many expensive prostate cancers in early stages. Mammograms are the similar (less cheap, but still life saving).
True, but this isn't a medical procedure. There are no surgeons etc involved. It amounts to the time for one mri tech to put the person in the machine, push the button. There is some expense in the reading and interpretation of the scans, but it's nowhere near the labor and other costs of surgury or endoscopy.
Perhaps AI can optimize MRI operating costs. But the question then is whether those savings would be passed on to the patient or accrued by the manufacturer and hospital as extra margin.
Only needed 1 tech for my MRI which lasted well under an hour. They may be expensive, but they don't get $100 an hour, so hard to believe that is a cost driver for a scan that costs over $1000.
1 tech to take the scan. And another one to actually examine/interpret the scan. Which for a full-body scan with no symptoms or specific areas to examine takes a lot longer than just taking the scan.
> They may be expensive, but they don't get $100 an hour
Radiology is one of the highest paying medical specialties. My cousin is one of the radiologists who interprets scans. He makes about $500k per year. Searching online, about $170/hr is average.
Yes, a properly done full body scan interpretation will take hours. It's about 30 minutes to analyze a scan of just someone's kidneys when there's already symptoms and doctor's note on what to look for.
The longest part is often just the paperwork and noting what was not seen.
The radiologist is a specialized medical doctor. They are not cheap. My neighbor is one, and she makes a considerable amount of money. They’re not technicians, and good ones command more than most surgeons.
Yes, but they can sit at a screen and analyze this stuff all day. It's not like a surgury where you have 3 or 4 OR staff and dozens of support staff to account for who all have to be on site and scrubbed in, etc.
MRIs use helium, which ain't cheap, although truthfully I don't know if the helium runs dry fast or if you can use the same helium supply indefinitely.
The helium is used whether you use the machine or not, it is just keeping the superconducting magnet cool (and you can't really put it out of field without an incredible cost and risk of never being able to put it in field again). Plus most recent machines have decent recycling systems (that do not reduce to 0 but over 90% reduction in many cases)
Magnet is fixed in an MRI and you just pulse fields in the XYZ directions to create gradients of magnetic field. The pulse emission and receiving antennas are fixed too.
In a CT scan, what is rotating is one or many xray sources and one or many detectors plus some electronics and cooling systems if needed.
PET scans have fixed rings of pairs of detectors. But they can also be combined with a CT in the same instrument.
All of that is included in the initial price of the machine. There is no real cost associated when running the machine itself (outside of when a preamp or pulse generator burns but that's rare).
We had advanced image processing techniques to detect tumors almost 20 years ago. With more advancements in computing power and AI techniques, it should be so much quicker and easier to do the same. The AI need not be conclusive but it could be a great assist to a radiologist who is looking at the scans.
MRIs use superconducting coils which can never be shutdown except in emergencies. There's a "quench" button which if you press the magnet turns off. But then I can't remember how much it is to turn back on but it's not a simple visit from a mechanic.
I looked into a full body scan about a year ago after hearing from someone I trust that they had one done.
While I didn’t end up moving forward with one, I was struck by how weak the arguments against having one done were. They amounted to:
- There’s a strong chance you’ll be sent on a wild goose chase or two after seeing something on the scan that is meaningless
- They only find something that actually turns out to be concerning in a small percentage of people
- This isn’t a cost effective approach to early diagnosis for most people
I’m sorry, but if I’m at a place in my life where this is a reasonable expense, even 1% odds such a scan turns up something genuinely troublesome is very worth it. It’s a life we are talking about.
> I’m sorry, but if I’m at a place in my life where this is a reasonable expense, even 1% odds such a scan turns up something genuinely troublesome is very worth it.
That's actually not how diagnostic tests work.
Because of Bayes theorem, tests that have a high likelihood of returning a positive result in a high-incidence population are totally useless when applied to asymptomatic random people in the general public.
Your likelihood of being harmed by one of these wild goose chases exceeds the chance that an early diagnosis will help you. First, you don't know there's a 1% chance that it'll turn something up - you don't know the chance at all. And you also don't know the likelihood and magnitude of harm chasing down false positives.
That's why we don't test people randomly for things they likely don't have.
It's just a logical fallacy and cognitive bias to think that doing something, anything, is better than doing nothing. Often that isn't the case.
> It’s a life we are talking about.
Which is why we shouldn't let our biases pull us in unhelpful directions.
No one says you have to follow up with anything invasive. I know someone who had a sinus polyp turn up on an MRI. Knowing what it was let him live with the symptoms it was causing without fearing that it was something much worse. I don't think he ever got it removed.
If you don't have symptoms and a scan showed an incidental something, you don't have to act. Personally, I'd rather know. And, if something does go wrong in the future you can say "I have an X in my left Y." Might give the doctor a place to start debugging.
Basically every human is significantly different inside, and they look nothing like the medical literature. Any scan will reveal all sorts of things that may or may not be at all clinically relevant.
Assuming you know which ones are problematic and which one's aren't. We don't. All the test provides is noise, not signal, when used in a low-incidence population.
The fact is there's no evidence such testing improves outcomes - if there was we'd just be doing it as part of the standard course of care. Folks are just demanding access to noise. Just go flip some coins instead, and save the medical resources for the people who need them.
Talk to a radiologist and ask them about the stuff they’ve found incidentally in “healthy” people. The average person is very much as described in the medical literature, with some small variations. This isn’t a good use of my time. I’m done replying.
bit off thread, I have a sinus polyp that seems to be under control when using nasal corticosteroids, with the massive risk of developing a dependency.
Let's say you have a test that's 80% accurate in telling you that you have cancer given you have cancer. Let's say the false positive rate is 10%.
- If 100% of the population has cancer, then a positive test means you're 80% likely to have cancer. This makes sense.
- If 10% of the population has cancer, then a positive test means you're only 50% likely to have cancer because of all the false positives in the general population.
- If 1% of the population has cancer, then a positive test means you're only 7% likely to have cancer.
- If 0.1% of the population has cancer, then a positive test means you're only 0.83% likely to have cancer.
Basically, the false positives dominate the results once you start applying the test to a low-incidence population. Which is why we don't.
One of the reasons why people get excited about room temperature superconductor is because it can make MRI imaging very cheap. Currently cooling the superconductors in the MRI machine is a significant part of the cost.
What strikes me, looking through their "conditions" page, is that they have many conditions listed that I'm not really concerned about. Like noticing if I'm missing a kidney, I'm good on that. But I do want to know if I have a brain tumor, because lots of that in my family. It's odd, I don't see brain tumor listed, but these things that are not much of a concern are.
The problem I have with this is not the scan per se but the fact that it's just more pressure to treat patients like a specimen in a petri dish rather than a product of their environment.
Dr. McCoy's tricorder was kind of a vision of tech enhancing the old fashioned "doctor making house calls with a little black bag" idea. Reality: Tech has created increased pressure for patients to travel to the medical facility rather than care coming to them.
One side effect: Doctors who don't do house calls can't incidentally notice things about your lifestyle that may contribute to the problem and may not know to ask or may not ask because it's an offensive thing to say and you may not know to volunteer the info. (If you knew, you might just fix it without seeing a doctor.)
I remember a scene from some TV show that made a powerful impression on me in my youth where the doctor burns a fur after seeing several patients. I think he realized it was a tick borne illness and the bear skin (iirc) was the source (of ticks).
It came very out of left field for me, but I've seen stories that suggest this is in part how medicine used to operate -- by the doctor noticing and fixing the cause of the problem in some cases -- and mostly doesn't anymore. Now we go in for drugs and surgeries and for some people that just means the start of an endless nightmare of chronic illness while doctors question their mental health and imply they are hypochondriacs.
When LK-99 was a possible room-temperature superconductor, among the first use cases people pointed to were cheaper, more-available MRIs. I can’t begrudge anyone with the means who decides to do this. And the demand has value. When was the last time a non-incumbent took a top-down look at reducing an MRI machine’s cost?
Full body scans are a common preventative measure in Taiwan.
My parents (expats, living in the US for over 50 years) flew back and got routine scans (MRI, PET, CT) in February for about $1000 USD total.
Similar to this story, they found a tumor on my dad's pancreas. A biopsy confirmed it, and he had surgery in August. They caught it at stage I. We're very lucky.
The latency from February til August was entirely convincing the US medical system to take his Taiwanese images seriously. They finally gave up and went back to Taiwan to get the procedure done.
I'm getting older myself and will absolutely be paying for any sort of imaging available.
This should be more broadly available to everyone. I'd be happy for more of my tax dollars to go to preventative care rather than rear guard action.
There was a similar discussion just over a year ago [1], and I was shocked then to find out that India offers full-body MRIs for probably 20% of the price.
Once amortized, The cost (outside of normal cryogenics resupply) is mainly the one of the personnel running it so a factor of 1/5 doesn't seem too surprising to me between India and US. I'm sure the overcharge from the hospital or clinic is not negligible either.
The framing of expanded early detection as "Silicon Valley's quest to live forever" seems uncharitable.