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How long until a daily brain scan and body scan is a part of everyone's routine, the same way brushing your teeth is? Problems like these are untreatable if le

How long until a daily brain scan and body scan is a part of everyone's routine, the same way brushing your teeth is? Problems like these are untreatable if left for too long, but if caught early, there's sometimes hope. The solution seems to be to develop as many types of passive scanners as possible. The problem is false positives. But wasting a month needlessly visiting the doctor doesn't seem that bad.

DanBC 12y ago
False positives don't mean a month of visiting a doctor - they mean several months of anxiety inducing "watchful waiting" or invasive biopsies. And false positives are not a rare event. False positives are very common. On top of that the radiation (from CT scans) increase the risk of cancer. Scans for healthy people are strongly discouraged. There's a possible benefit if you have any of the genetic markers for lung cancer or are otherwise at risk of lung cancer - heavy lifelong smoker for example.
- philjohn 12y ago
  Yep. My wife has yearly scans because of a tumour supressor gene mutation and last year they thought they spotted something on the ultrasound, so sent her for a CT. CT showed that it was pretty bad, que months of stressing and worrying about what was going to happen. Turns out it was a false positive, caused by an accessory spleen looking like a tumour. False positives do happen, and they can be pretty devastating - it took quite a while for her to get back to normal.
  - zo1 12y ago
    Would you care to share with us how you were able to determine that she had such a gene? Was it some sort of byproduct of a normal scan/test? Or was it some sort of specificly requested test you went somewhere to get tested for? Or?
    - qt7 12y ago
      I don't know about your country, but genetic screening / testing is something you need to ask for, not something that happens as a by-product of a CT scan.
  - qt7 12y ago
    If you worry that much about a false positive, I'm sorry for you, but you have no idea how much worse things may get. Many people don't get to complain about a false positive! Stressing and worrying are both several orders of magnitude better than suffering and dying. Source: My case wasn't a false positive.
    - DanBC 12y ago
      In the context of full body scanning: false positives include spots on the lung. So now you have someone who thinks they have might lung cancer, when in fact they probably have almost harmless scars from chicken pox. But what do you do if you think you have lung cancer? Do you go and get biopsies? The stress from that result is significant and shouldn't be dismissed as something trivial.
    - onewaystreet 12y ago
      People aren't worrying over a false positive. They don't know it's a false positive. In that moment their worry is just as genuine as yours is.
      - qt7 12y ago
        Of course you're right, but there's a misunderstanding there. My point is people who went through the experience of having test results compatible with cancer and then discover it is just a false positive (which technically it's not even true, there's no cancer diagnosis before a biopsy, it just can't be excluded), well, these very people seem to speak out against screening, or adopting more extensive screening policies, because they had a "false positive", and "it's stressful". I am pretty sure all the people whose lives were saved by screening find that pretty selfish.
        lomnakkus 12y ago
        I think you're misunderstanding something. This has nothing to do with selfishness -- you're only really considering the upside. The harm/good ratio of screening depends crucially of the false positive/negative ratio vs. the actual prevalence of the condition or disease being screened for. (Plus, obviously the psychological/medical "cost" of a false negative/positive.) I would recommend the talk at [1]. This particular issue is brought up about midway through the video, but I recommend watching the whole thing. [1] http://www.ted.com/talks/peter_donnelly_shows_how_stats_fool_juries http://www.ted.com/talks/peter_donnelly_shows_how_stats_fool...
- mcphage 12y ago
  > And false positives are not a rare event. False positives are very common. Sure, but if you're scanning daily (or close to it), then you don't need to do anything immediately for a positive. You see a growth that looks like it might be cancer—then have the doctor watch it. If you're scanning often, then you'll see any changes. Does it grow? Then it's something to be concerned about. Does it stay the same? Then you don't need to worry. With frequent enough scans, finding something isn't a cause for any alarm. You can watch how it changes, and decide if it's a concern based on that. Like skin moles. Yes, they could be a problem, but if you have one, you don't need to worry unless it starts changing. Just having one doesn't cause anxiety.
  - 3am 12y ago
    That's an insane amount of radiation, and would substantially increase your risk of fatal cancer. A single CT scan is roughly a years worth of normal radiation exposure, and then targeted to a single area of the body.
    - mcphage 12y ago
      Right, I wouldn't want to do it with CT scans. But I think it's an area where a less dangerous, cheaper scanning method might save a lot of lives, even with our current techniques for treating cancer. Frequent scanning would mean people would find tumors when they're smaller, and only treat the ones which behave dangerously.
      - 3am 12y ago
        edit: I'm replacing my entire previous comment about the superiority of ct/pet-ct vs *mri scanning; it looks like some groups are doing work with MRIs that are comparable in accuracy and nearing clinical use. I still think daily whole body scans are a spectacular waste of human capital for relatively little benefit.
        mcphage 12y ago
        > I still think daily whole body scans are a spectacular waste of human capital for relatively little benefit. I agree, and I'm not recommending we do that right now. But imagine if we had cheap, fast ways to do the scans. So much money is being pumped into cancer treatment right now, I'm just wondering if better cancer detection might be more beneficial. Our current treatment methods might get us a lot farther because we'd use them when the tumors are smaller, and we'd have a much better sense of how aggressive a tumor is.
- danielweber 12y ago
  And then the lawyers descend on all the false negatives. "Doctor, why did you miss this shadow on this photo? Two years later cancer was found there."
3rd3 12y ago
X-ray and CT imaging however slighly increases the cancer risk. http://www.cancer.org/cancer/cancercauses/radiationexposureandcancer/xraysgammaraysandcancerrisk/x-rays-gamma-rays-and-cancer-risk-do-xrays-and-gamma-rays-cause-cancer http://www.cancer.org/cancer/cancercauses/radiationexposurea...
- josephagoss 12y ago
  I thought a MRI is both more accurate and safer.
  - geographomics 12y ago
    MRI does have some caveats - it's not available to people with ferromagnetic material embedded within them, and not suitable for those who are claustrophobic. Also CT scans tend to be more accurate for bone, and are quicker to perform so less susceptible to the subject moving about. There's also the issue that, at present, MRI scans are considerably more expensive than CT.
    - seren 12y ago
      And a MRI needs an enclosure, I am not aware of small portable MRI systems that would allow you to image a single leg, or breast. X-Rays are more dangerous but are more versatile in some cases.
      - VLM 12y ago
        COTS for maybe a decade now. Look at sports medicine equipment suppliers. I'm unaware of any breast oriented products but they probably exist. Google for Esaote (my coworker got scanned a couple times by their product) and "extremity MRI" As you'd imagine the economics are non-trivial. The machine is smaller and cheaper that a full size MRI (google claims its fraction of a million, like the cost of a house) but obviously something that can only scan knees and ankles and elbows is a pretty tough sell unless you're a sports medicine practice in which case its a pretty easy sell... On the other hand if a "whole body sized" MRI costs $2500 per scan, then you've only got to scan maybe 100 knees to pay the capital cost of a dedicated extremity MRI. And how long would that take at a busy sports medicine practice, like a week? I would not describe the machine as portable. Being a giant magnet you probably need a special safe room to operate it, so I don't envision paramedic/EMT ever having a MRI in the ambulance or whatever. WRT discussion in the comments about claustrophobia I don't mind the small spaces so much as being chained down for an hour or so, that drives me nuts. My MiL went thru some tests for her gallbladder that took hours, I'd be clawing at the walls after ten minutes. Also if I could get nitrous for my wisdom teeth I see no obvious reason a MRI patient couldn't be gassed but they "never" seem to do that, which I find weird. For $2500 for a full body scan you could at least give me a couple shots of vodka.
dkbrk 12y ago
False positives aren't inherently a problem. If you have accurate understanding of the sensitivity and specificity of a test, then you can take action to maximise the utility of the expected outcome. This means, for example, not necessarily performing a biopsy just because something is there (but it's probably benign). The cost of invasive procedures such as biopsies, and risk-increasing tests such as CT scans has to be balanced against their benefits. Of course, there is no risk with a full-body MRI scan. The machine itself is expensive, but otherwise it nominally only costs electricity, maintenance and operation. If full-body scans were, as you say, routine, the cost of the machine would be amortised and an economy of scale should prevail. The problem is legal; if a doctor sees something on a scan and doesn't take action, they can be sued. This is the case even if there is negative expected utility from performing the test due to the low probability of an actual malignant condition. Due to this, it is not uncommon to hear doctors say that full-body scans do more harm than good. Until the legal system starts to account for rational choices based on statistical information, this problem is going to persist.
- perlgeek 12y ago
  > Of course, there is no risk with a full-body MRI scan. Not quite true. While the scan itself isn't harmful, the strong magnetic fields, RF fields and noise have caused several accidents, some fatal. Compare for example http://www.auntminnie.com/index.aspx?sec=sup_n&sub=mri&pag=dis&ItemID=96699 http://www.auntminnie.com/index.aspx?sec=sup_n&sub=mri&pag=d... "The FDA's Manufacturer and User Facility Device Experience (MAUDE) database documented a total of 40 incidents for MRI in 2004. In 2009, the total more than quadrupled, to 193 reported adverse events." Example of a fatality: http://abcnews.go.com/US/story?id=92745 http://abcnews.go.com/US/story?id=92745 > False positives aren't inherently a problem. If you have accurate understanding of the sensitivity and specificity of a test, then you can take action to maximise the utility of the expected outcome. False positives can still cause huge psychological strain on the involved person(s).
- yummyfajitas 12y ago
  If full-body scans were, as you say, routine, the cost of the machine would be amortised and an economy of scale should prevail. That's not really true. The cost of the machine is amortised by having it be in use at all times. In my experience MRI's are already fully utilized. I've had 3 in the past year. Even during Diwali there was always someone immediately before and immediately after me, and I never have much choice about appointment times.
Multics 12y ago
New ‘lab-on-a-chip’ could revolutionize early diagnosis of cancer[0] [0] http://www.kurzweilai.net/new-lab-on-a-chip-could-revolutionize-early-diagnosis-of-cancer http://www.kurzweilai.net/new-lab-on-a-chip-could-revolution...
deleted 12y ago
[deleted]
debacle 12y ago
It's not really necessary to scan anything if you can collect the symptomatic biometrics and detect possible issues just based on deviance from normal variations.
grecy 12y ago
In the UK when you move house you're required to go and have a checkup with your new local doctor. It's preventative health care, not "sick care".
- beejiu 12y ago
  In reality, you'll have your blood pressure checked by a nurse, not a doctor, and a load of boxes ticked on a form. Still worthwhile, of course, but my own experience with my local doctors is that they are under a huge amount of pressure with little time to see patients for preventative medicine. It also depends very much on where you live.

DanBC 12y ago

False positives don't mean a month of visiting a doctor - they mean several months of anxiety inducing "watchful waiting" or invasive biopsies. And false positives are not a rare event. False positives are very common. On top of that the radiation (from CT scans) increase the risk of cancer. Scans for healthy people are strongly discouraged. There's a possible benefit if you have any of the genetic markers for lung cancer or are otherwise at risk of lung cancer - heavy lifelong smoker for example.

philjohn 12y ago
Yep. My wife has yearly scans because of a tumour supressor gene mutation and last year they thought they spotted something on the ultrasound, so sent her for a CT. CT showed that it was pretty bad, que months of stressing and worrying about what was going to happen. Turns out it was a false positive, caused by an accessory spleen looking like a tumour. False positives do happen, and they can be pretty devastating - it took quite a while for her to get back to normal.
- zo1 12y ago
  Would you care to share with us how you were able to determine that she had such a gene? Was it some sort of byproduct of a normal scan/test? Or was it some sort of specificly requested test you went somewhere to get tested for? Or?
  - qt7 12y ago
    I don't know about your country, but genetic screening / testing is something you need to ask for, not something that happens as a by-product of a CT scan.
- qt7 12y ago
  If you worry that much about a false positive, I'm sorry for you, but you have no idea how much worse things may get. Many people don't get to complain about a false positive! Stressing and worrying are both several orders of magnitude better than suffering and dying. Source: My case wasn't a false positive.
  - DanBC 12y ago
    In the context of full body scanning: false positives include spots on the lung. So now you have someone who thinks they have might lung cancer, when in fact they probably have almost harmless scars from chicken pox. But what do you do if you think you have lung cancer? Do you go and get biopsies? The stress from that result is significant and shouldn't be dismissed as something trivial.
  - onewaystreet 12y ago
    People aren't worrying over a false positive. They don't know it's a false positive. In that moment their worry is just as genuine as yours is.
    - qt7 12y ago
      Of course you're right, but there's a misunderstanding there. My point is people who went through the experience of having test results compatible with cancer and then discover it is just a false positive (which technically it's not even true, there's no cancer diagnosis before a biopsy, it just can't be excluded), well, these very people seem to speak out against screening, or adopting more extensive screening policies, because they had a "false positive", and "it's stressful". I am pretty sure all the people whose lives were saved by screening find that pretty selfish.
      - lomnakkus 12y ago
        I think you're misunderstanding something. This has nothing to do with selfishness -- you're only really considering the upside. The harm/good ratio of screening depends crucially of the false positive/negative ratio vs. the actual prevalence of the condition or disease being screened for. (Plus, obviously the psychological/medical "cost" of a false negative/positive.) I would recommend the talk at [1]. This particular issue is brought up about midway through the video, but I recommend watching the whole thing. [1] http://www.ted.com/talks/peter_donnelly_shows_how_stats_fool_juries http://www.ted.com/talks/peter_donnelly_shows_how_stats_fool...
mcphage 12y ago
> And false positives are not a rare event. False positives are very common. Sure, but if you're scanning daily (or close to it), then you don't need to do anything immediately for a positive. You see a growth that looks like it might be cancer—then have the doctor watch it. If you're scanning often, then you'll see any changes. Does it grow? Then it's something to be concerned about. Does it stay the same? Then you don't need to worry. With frequent enough scans, finding something isn't a cause for any alarm. You can watch how it changes, and decide if it's a concern based on that. Like skin moles. Yes, they could be a problem, but if you have one, you don't need to worry unless it starts changing. Just having one doesn't cause anxiety.
- 3am 12y ago
  That's an insane amount of radiation, and would substantially increase your risk of fatal cancer. A single CT scan is roughly a years worth of normal radiation exposure, and then targeted to a single area of the body.
  - mcphage 12y ago
    Right, I wouldn't want to do it with CT scans. But I think it's an area where a less dangerous, cheaper scanning method might save a lot of lives, even with our current techniques for treating cancer. Frequent scanning would mean people would find tumors when they're smaller, and only treat the ones which behave dangerously.
    - 3am 12y ago
      edit: I'm replacing my entire previous comment about the superiority of ct/pet-ct vs *mri scanning; it looks like some groups are doing work with MRIs that are comparable in accuracy and nearing clinical use. I still think daily whole body scans are a spectacular waste of human capital for relatively little benefit.
      - mcphage 12y ago
        > I still think daily whole body scans are a spectacular waste of human capital for relatively little benefit. I agree, and I'm not recommending we do that right now. But imagine if we had cheap, fast ways to do the scans. So much money is being pumped into cancer treatment right now, I'm just wondering if better cancer detection might be more beneficial. Our current treatment methods might get us a lot farther because we'd use them when the tumors are smaller, and we'd have a much better sense of how aggressive a tumor is.
danielweber 12y ago
And then the lawyers descend on all the false negatives. "Doctor, why did you miss this shadow on this photo? Two years later cancer was found there."

3rd3 12y ago

X-ray and CT imaging however slighly increases the cancer risk. http://www.cancer.org/cancer/cancercauses/radiationexposureandcancer/xraysgammaraysandcancerrisk/x-rays-gamma-rays-and-cancer-risk-do-xrays-and-gamma-rays-cause-cancer http://www.cancer.org/cancer/cancercauses/radiationexposurea...

josephagoss 12y ago
I thought a MRI is both more accurate and safer.
- geographomics 12y ago
  MRI does have some caveats - it's not available to people with ferromagnetic material embedded within them, and not suitable for those who are claustrophobic. Also CT scans tend to be more accurate for bone, and are quicker to perform so less susceptible to the subject moving about. There's also the issue that, at present, MRI scans are considerably more expensive than CT.
  - seren 12y ago
    And a MRI needs an enclosure, I am not aware of small portable MRI systems that would allow you to image a single leg, or breast. X-Rays are more dangerous but are more versatile in some cases.
    - VLM 12y ago
      COTS for maybe a decade now. Look at sports medicine equipment suppliers. I'm unaware of any breast oriented products but they probably exist. Google for Esaote (my coworker got scanned a couple times by their product) and "extremity MRI" As you'd imagine the economics are non-trivial. The machine is smaller and cheaper that a full size MRI (google claims its fraction of a million, like the cost of a house) but obviously something that can only scan knees and ankles and elbows is a pretty tough sell unless you're a sports medicine practice in which case its a pretty easy sell... On the other hand if a "whole body sized" MRI costs $2500 per scan, then you've only got to scan maybe 100 knees to pay the capital cost of a dedicated extremity MRI. And how long would that take at a busy sports medicine practice, like a week? I would not describe the machine as portable. Being a giant magnet you probably need a special safe room to operate it, so I don't envision paramedic/EMT ever having a MRI in the ambulance or whatever. WRT discussion in the comments about claustrophobia I don't mind the small spaces so much as being chained down for an hour or so, that drives me nuts. My MiL went thru some tests for her gallbladder that took hours, I'd be clawing at the walls after ten minutes. Also if I could get nitrous for my wisdom teeth I see no obvious reason a MRI patient couldn't be gassed but they "never" seem to do that, which I find weird. For $2500 for a full body scan you could at least give me a couple shots of vodka.

dkbrk 12y ago

False positives aren't inherently a problem. If you have accurate understanding of the sensitivity and specificity of a test, then you can take action to maximise the utility of the expected outcome. This means, for example, not necessarily performing a biopsy just because something is there (but it's probably benign). The cost of invasive procedures such as biopsies, and risk-increasing tests such as CT scans has to be balanced against their benefits. Of course, there is no risk with a full-body MRI scan. The machine itself is expensive, but otherwise it nominally only costs electricity, maintenance and operation. If full-body scans were, as you say, routine, the cost of the machine would be amortised and an economy of scale should prevail. The problem is legal; if a doctor sees something on a scan and doesn't take action, they can be sued. This is the case even if there is negative expected utility from performing the test due to the low probability of an actual malignant condition. Due to this, it is not uncommon to hear doctors say that full-body scans do more harm than good. Until the legal system starts to account for rational choices based on statistical information, this problem is going to persist.

perlgeek 12y ago
> Of course, there is no risk with a full-body MRI scan. Not quite true. While the scan itself isn't harmful, the strong magnetic fields, RF fields and noise have caused several accidents, some fatal. Compare for example http://www.auntminnie.com/index.aspx?sec=sup_n&sub=mri&pag=dis&ItemID=96699 http://www.auntminnie.com/index.aspx?sec=sup_n&sub=mri&pag=d... "The FDA's Manufacturer and User Facility Device Experience (MAUDE) database documented a total of 40 incidents for MRI in 2004. In 2009, the total more than quadrupled, to 193 reported adverse events." Example of a fatality: http://abcnews.go.com/US/story?id=92745 http://abcnews.go.com/US/story?id=92745 > False positives aren't inherently a problem. If you have accurate understanding of the sensitivity and specificity of a test, then you can take action to maximise the utility of the expected outcome. False positives can still cause huge psychological strain on the involved person(s).
yummyfajitas 12y ago
If full-body scans were, as you say, routine, the cost of the machine would be amortised and an economy of scale should prevail. That's not really true. The cost of the machine is amortised by having it be in use at all times. In my experience MRI's are already fully utilized. I've had 3 in the past year. Even during Diwali there was always someone immediately before and immediately after me, and I never have much choice about appointment times.

Multics 12y ago

New ‘lab-on-a-chip’ could revolutionize early diagnosis of cancer[0] [0] http://www.kurzweilai.net/new-lab-on-a-chip-could-revolutionize-early-diagnosis-of-cancer http://www.kurzweilai.net/new-lab-on-a-chip-could-revolution...

deleted 12y ago

[deleted]

debacle 12y ago

It's not really necessary to scan anything if you can collect the symptomatic biometrics and detect possible issues just based on deviance from normal variations.

grecy 12y ago

In the UK when you move house you're required to go and have a checkup with your new local doctor. It's preventative health care, not "sick care".

beejiu 12y ago
In reality, you'll have your blood pressure checked by a nurse, not a doctor, and a load of boxes ticked on a form. Still worthwhile, of course, but my own experience with my local doctors is that they are under a huge amount of pressure with little time to see patients for preventative medicine. It also depends very much on where you live.