Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

One whole-body MRI could replace multiple cancer scans

pharmatimes.com

Post reply on HN
Print view View original

151–160 of 236 posts

Re: One whole-body MRI could replace multiple cancer scans

#151

Post by ska »

rolleiflex wrote: post #67
nknealk wrote: post #13

Many doctors hate full body scans. Every individual has a handful of anomalies which are almost always benign. They show up on full body scans and chasing them down comes with cost and patient risk. I have a hard time with reporting like this that doesn't quantify cost of biopsy on false-positives as well as cost of complications from examining false-positives. Source: worked in clinical research for 2 years.

A decent portion of my family are MDs. This is accurate. However, this is also one of the places where it's quite disappointing to see human squishiness in action. When we opt to not receive data because we know there'll likely be non-malignant anomalies, we are also depriving ourselves of the raw data that allows us to discern non-malignant from malignant, data which would help very much in deciding on the cases we…

   Had we enforced a full-body MRI for every patient, we would quickly amass enough imaging data to know which anomalies are malignant and which are not to a very high degree
These sorts of statements come across as naive optimism at best. And I like our long term odds of increasing clinical efficacy, and have designed and worked on several systems in this space that are in clinical use.

Re: One whole-body MRI could replace multiple cancer scans

#152

Post by jedberg »

codingdave wrote: post #127
jedberg wrote: post #111

I've had this idea floating in my head for a while. Provide free annual full body MRIs to people, including being read by a radiologist, which they can take to anyone they want (doctor, lawyer, whatever). In exchange, they agree to send the org a copy of all their past and future medical records. The records are anonymized and tied to the MRIs. The MRIs and medical data is then pumped through machine learning algorit…

> agree to send the org a copy of all their past and future medical records.. Even ignoring the issue of false positives, which alone is serious enough to make this a dubious idea... that is an extreme thing to ask of people. All my future records? I have no idea what my future holds, and what I may feel about that as I age and experience new problems. Nor how my family might feel about it on my deathbed. I applaud n…

Well if you didn't like the terms you wouldn't have to get your free scan. :) I hear where you're coming from, but the data isn't nearly as useful if we don't get to find out what diseases you get later in life. The whole point is to train an AI so we need the future data to make it work.

Re: One whole-body MRI could replace multiple cancer scans

#153

Post by Brakenshire »

tellak wrote: post #139
Brakenshire wrote: post #126

Earlier quoted context omitted.

> The collection process itself can be dangerous or unpleasant for the patient. That’s asinine, obviously he doesn’t mean more data is always better even if the test is invasive or dangerous. > Biopsies caused by benign findings from a full body scan are not without pain, emotional distress, risk or cost to the patient. Period. It must be weighed against the benefit that the patient would recieve (all in the aggregat…

> That’s asinine, obviously he doesn’t mean more data is always better even if the test is invasive or dangerous. With him classifying all MDs as idiots, no it is not asinine. I’ve known few academic physicians that would turn down data if it can be ethically obtained. The difference between the medical profession and, say Google, is that we as a general rule do not consider the populace one big lab to experiment on…

I think the key distinction is that clinical science rather than medicine needs as much data as possible, and then medicine needs to follow clinical science.

And then, that medicine needs to become much more sophisticated in dealing with risk and uncertainty, given the absurd complexity of the problem domain. Doctors are not idiots but they are no more than human while trying to do an impossibly difficult job, and are far too cocksure given that context. They should be asking for as much help as they can get, which is not the reality of the situation. See something as simple as the resistance to checklists in surgery for example, despite the evidence.

I see your point about ethical breaches which have taken place. I would tend to think of those as abuses of power rather than coming from an ideological position, but that may not be correct. You’re certainly right about the dangers of a beta test mentality.

Re: One whole-body MRI could replace multiple cancer scans

#154

Post by WoodenChair »

tellak wrote: post #134
rolleiflex wrote: post #67

Earlier quoted context omitted.

A decent portion of my family are MDs. This is accurate. However, this is also one of the places where it's quite disappointing to see human squishiness in action. When we opt to not receive data because we know there'll likely be non-malignant anomalies, we are also depriving ourselves of the raw data that allows us to discern non-malignant from malignant, data which would help very much in deciding on the cases we…

I am actually an MD. > Had we enforced a full-body MRI for every patient, we would quickly amass enough imaging data to know which anomalies are malignant and which are not to a very high degree How, pray tell, are we actually determining which are malignant and which are not?? I’ll give you a hint: the charitable explanation is you are completely ignorant, the less charitable one is that you consider Mengele and Ish…

> How, pray tell, are we actually determining which are malignant and which are not?

When people on this forum speculate about things like this, I assume they are thinking of some future ML application. Of course you're right though, that is not doable today. The point of the OP is that if we collected more data perhaps it would be possible.

> the less charitable one is that you consider Mengele and Ishii modern medicine heroes.

The ad hominem attacks against the OP are completely unnecessary.

> I am actually an MD.

The start of your post feels like "appeal to authority."

Re: One whole-body MRI could replace multiple cancer scans

#155

Post by tomcam »

WoodenChair wrote: post #154
tellak wrote: post #134

Earlier quoted context omitted.

I am actually an MD. > Had we enforced a full-body MRI for every patient, we would quickly amass enough imaging data to know which anomalies are malignant and which are not to a very high degree How, pray tell, are we actually determining which are malignant and which are not?? I’ll give you a hint: the charitable explanation is you are completely ignorant, the less charitable one is that you consider Mengele and Ish…

> How, pray tell, are we actually determining which are malignant and which are not? When people on this forum speculate about things like this, I assume they are thinking of some future ML application. Of course you're right though, that is not doable today. The point of the OP is that if we collected more data perhaps it would be possible. > the less charitable one is that you consider Mengele and Ishii modern medi…

> The start of your post feels like "appeal to authority."

Sounds like a declaration of fact to me

Re: One whole-body MRI could replace multiple cancer scans

#156

Post by outlace »

nnq wrote: post #115
nknealk wrote: post #13

Many doctors hate full body scans. Every individual has a handful of anomalies which are almost always benign. They show up on full body scans and chasing them down comes with cost and patient risk. I have a hard time with reporting like this that doesn't quantify cost of biopsy on false-positives as well as cost of complications from examining false-positives. Source: worked in clinical research for 2 years.

MDs are idiots in this regard. Mainly because they've been thought medicine by other idiots. They have this stupid idea that "too much data" is bad, also stuff being a sign that you're a bad doctor if you order too much tests etc. It's a whole can of worms of crappy rationalizations here, that also hides the fact that doctors are not capable or trained to correctly deal with large volumes of data, so they know they w…

Let’s just assume for sake of argument that that is true, more data is always better. And let’s assume collecting more data is not cost prohibitive on a population scale. In the real world, physicians have a major incentive to practice defensive medicine to avoid litigation.

If you order an unnecessary test and it shows something abnormal, even though in your clinical judgement it is not likely to be worrisome, you now feel a strong impulse to spend thousands more dollars to completely rule out it’s not some 1 in a million rare cancer lest you get sued. So some systemic issues at play here, not that “doctors are idiots.”

In data science, sure more data is always better but you’re not worried that more data is going to lead you to a traumatizing malpractice lawsuit.

Re: One whole-body MRI could replace multiple cancer scans

#157

Post by m463 »

nknealk wrote: post #13

Many doctors hate full body scans. Every individual has a handful of anomalies which are almost always benign. They show up on full body scans and chasing them down comes with cost and patient risk. I have a hard time with reporting like this that doesn't quantify cost of biopsy on false-positives as well as cost of complications from examining false-positives. Source: worked in clinical research for 2 years.

Dentists don't have any trouble taking regular full-mouth x-rays. Maybe this is because this translates into money for each problem found.

In the same way, skin doctors take photos of body moles to see if any changes occur between visits.

I think internal doctors should start viewing this as inevitable.

Then up-front develop "watchful waiting" plans that over the course of time and several scans chase down any suspicious changes.

Re: One whole-body MRI could replace multiple cancer scans

#158

Post by WoodenChair »

tomcam wrote: post #155
WoodenChair wrote: post #154

Earlier quoted context omitted.

> How, pray tell, are we actually determining which are malignant and which are not? When people on this forum speculate about things like this, I assume they are thinking of some future ML application. Of course you're right though, that is not doable today. The point of the OP is that if we collected more data perhaps it would be possible. > the less charitable one is that you consider Mengele and Ishii modern medi…

> The start of your post feels like "appeal to authority." Sounds like a declaration of fact to me

What I mean is, just because the person is "actually an MD" doesn't mean the person has expertise in this specific area yet the person is using it to claim such. I.E. some might call me a computer scientist, but that doesn't mean I have enough expertise in machine learning, a sub-discipline, to say definitively that the OP's idea about using full body scan data is feasible.

Should I have started my post "I am actually a computer scientist." No, right? That would be an appeal to authority that doesn't prove I know anything about what I'm talking about. Now, if the person had started with "I am a radiologist who has looked at empirical data about full body scans versus more selective scans." that would be a more useful and valid statement.

Re: One whole-body MRI could replace multiple cancer scans

#159

Post by abecedarius »

arkades wrote: post #120
abecedarius wrote: post #117

Earlier quoted context omitted.

Framing it as a choice between "have a cookbook decision tree that's been validated by RCTs in exactly this context" and "do a lot of costly (in resources and side effects) followup tests to show we're doing everything we can" is an example of the irrationality that needs fixing. People are capable of actually reasoning with uncertainty when they care about outcomes. When it's you, personally, facing a decision in yo…

It’s not “cookbook decision tree”, it’s “data from which to make meaningful inferences about this finding.” It would be nice if we always have that; with incidental findings, we often don’t.

Put it this way: my doctor ordered a test for me, got the results, and made a recommendation. I was ignorant of both the costs (of all sorts) beforehand and of the product of probability and utility on which he (implicitly and unavoidably unless irrationally) based the decision. He did make a meaningful inference from this data, as anyone must to make a decision; he just refused to help me, as a consultant instead of a master, to make my own.

Re: One whole-body MRI could replace multiple cancer scans

#160

Post by Wowfunhappy »

mattkrause wrote: post #112
rolleiflex wrote: post #67

Earlier quoted context omitted.

A decent portion of my family are MDs. This is accurate. However, this is also one of the places where it's quite disappointing to see human squishiness in action. When we opt to not receive data because we know there'll likely be non-malignant anomalies, we are also depriving ourselves of the raw data that allows us to discern non-malignant from malignant, data which would help very much in deciding on the cases we…

You're understating the costs. Determining whether something is (non) malignant isn't trivial. It often requires a more invasive test (e.g., biopsy, exploratory surgery). We try to avoid those procedures not just because we're cheap or afraid, but because they have a real risk of harming us 'squishy humans'. For example, detecting prostate cancer a few months earlier is often not a huge win on its own. It is even les…

> For example, detecting prostate cancer a few months earlier is often not a huge win on its own. It is even less of a success if doing so requires that four people have allergic reactions to the anesthetic and two others acquire some kind of infection at the biopsy site.

Then the doctor should recommend not attempting that type of detection.

I find it quite hard to believe that, in an ideal world (!), less data would actually be better. The doctor should still have the ability (at least in theory) to decide what information is worth investigating further, and what should be ignored.

Post reply on HN