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One whole-body MRI could replace multiple cancer scans

pharmatimes.com

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

#71

Post by internet_user »

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.

It is so much more efficient to tell people to go home and rest. That way you can triple book and make 3x the money.

Insurance reimbursement is exactly the same for your appointment, regardless if the patient lives or dies, or even gets correct diagnosis, nevermind correct tests.

/s

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

#72

Post by internet_user »

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…

It's just more profitable to fob off patients as fast as you can, good for business.

In-depth investigations have massive opportunity costs for someone reimbursed on piece-work basis, takes up way too much time.

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

#73

Post by jmhmd »

jcims wrote: post #56
arkades wrote: post #46

Earlier quoted context omitted.

We don’t advocate less frequent scans, we advocate targeted scans. Because the probability of a positive result being a false positive depends heavily on the population. In a population with a high baseline frequency, the probability of a positive being false is relatively low; in a population with a low baseline frequency, the likelihood of a positive being false is relatively high. So, you don’t mammogram every per…

Sitting in the oncology dept right now with my wife who’s gaving complications from a tumor. I’d just be happy with peer reviews of radiology reports so fuckups don’t cost us three months of potential treatment. I’m sitting bedside wading through pull requests for software installation scripts. How is it the opinions of folks on my team for a bullshit process get more scrutiny than a potentially life-altering assessm…

Radiologist here. Sorry to hear about about your wife's complications. Most radiology departments do participate in a peer review process as part of internal quality assurance. Not every report is necessarily peer-reviewed, largely due to time constraints (radiologists can read hundreds of mammograms in a day), and not all modalities are required to participate (I believe mammography is optional).

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

#74

Post by willwagner »

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.

I've heard this many times before and don't doubt thats the way doctors feel but it's a little like not monitoring production because you don't want developers chasing down minor production issues.

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

#75

Post by CWuestefeld »

benaadams wrote: post #33
hammock wrote: post #6

Earlier quoted context omitted.

State of the art MRI machine costs $3 million up front. Would take 20 scans a week, every week, for 10 years to break even on that investment at $300 per scan. Not counting physician & staff time or cost of capital.

NHS isn't a for profit healthcare system; and they'll break even earlier on the early detection and diagnosis as since it covers you for life treating you early is less expensive then treating you later when the treatment costs would be higher. Considerations would be different if the MRI scanner was running as for profit; or you could switch coverage so the later costs would be borne by someone else.

treating you early is less expensive then treating you later when the treatment costs would be higher.

This is true retrospectively, for anyone who it turns out really has the disease.

But studies show that prospectively (when you don't know if somebody actually has a given disease), the cost of preventative care - including follow-up tests and unnecessary treatments - exceeds the benefit that you outlined.

EDIT: add quote to clarify what I'm responding to.

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

#76

Post by arkades »

MegaButts wrote: post #57
arkades wrote: post #46

Earlier quoted context omitted.

We don’t advocate less frequent scans, we advocate targeted scans. Because the probability of a positive result being a false positive depends heavily on the population. In a population with a high baseline frequency, the probability of a positive being false is relatively low; in a population with a low baseline frequency, the likelihood of a positive being false is relatively high. So, you don’t mammogram every per…

But doesn't this approach make it nigh impossible to catch people that don't fit the mold? It almost seems like it becomes a tautology, by not capturing the diseases in people you don't think have them, and only looking in people that you do think have them. And the only way to change the mold is for enough people to likely die that you reevaluate the model. I am not a doctor, but I cannot fathom why a doctor would e…

Well, that’s part of why there’s constant research into what risk factors / predictive factors are. These aren’t mutually exclusive activities.

“Data” implies something neutral. Nothing about lab tests is neutral. Without contextual information and studies on how to -interpret- a finding, it’s just potentially terrifying noise. And terror usually results in action. Poorly informed action is often harmful. So... we are trying to prevent harm to our patients.

We are earnestly working on all fronts to build the studies to better interpret these findings. But we just aren’t there yet.

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

#77

Post by roywiggins »

chongli wrote: post #23
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.

This sounds to me like doing a full workup on blood chemistry. Individuals vary so much that you can get false positives. Wouldn't it be more useful as a baseline? Scan once and store it, then scan every few years and compare. If any of the "anomalies" has grown or new ones have appeared between scans, then they might be worth a second look?

MRI scanners can only barely do quantitative evaluations... between different scanners, and different scanning protocols, your body may look quite a bit different and it is hard to know exactly how much variability to attribute to inter-scanner differences.

There are whole studies done to try and quantify this, and it requires sending "human phantoms"- test subjects- around to different scanners, which requires you to physically take one subject around to several scanners operated by different people and stick them in there for a while. It's really involved.

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

#78

Post by arkades »

internet_user wrote: post #60
arkades wrote: post #37

Earlier quoted context omitted.

(1) Because we do not have the body of knowledge that tells us how to predict an anomaly is not worth pursuing. It would require a lot of major, expensive, long-term studies involving non- negligible chemical exposures in$ asymptomatic people in order to get a good idea of what the “healthy” anomaly looks like. $ many of these MRIs require contrast material. (2) Malpractice for a missed cancer in most states has an e…

> statistically appropriate call. but factually incorrect call is apparently OK, because they are treating "median person", and not the actual patient. This has to do with money - and nothing else.

No, it has to do with avoiding harm to patients. I don’t make one red cent more or less from sending someone to an MRI or not. I do care about wasteful testing that is more likely to stress out a patient and send them down a rabbit-hole of follow-up tests with potential complications and costs (to them), if there’s not a reasonable chance of an outweighing clinical benefit for them.

And of course we make statistical calls! When you’re deciding -prospectively- whether a course of testing or treatment is in a patient’s best interest, you have to look at the stats on likely benefits and harms of various courses of action. I’d love to know what my patients have before hand, so I could avoid dealing with probabilities, but I haven’t been blessed with that particular power. I’d love for the data to exist to tell me how to interpret a result in my precise patient rather than a larger population she belongs to, but “solitary pulmonary nodules in 33-year old men who smoked twice in college and live half a mile from a freeway with two episodes of bronchitis in their teens” is a study that hasn’t been conducted yet. One day perhaps it will be, and if so, I’ll be grateful for it. But right now that data doesn’t exist, so we use what we have, and use our judgment to tailor it to the patient in front of us - imperfectly.

I recommend reading “overdiagnosed” by Gilbert Welch.

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

#79

Post by aantix »

internet_user wrote: post #72
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…

It's just more profitable to fob off patients as fast as you can, good for business. In-depth investigations have massive opportunity costs for someone reimbursed on piece-work basis, takes up way too much time.

Then more money needs to be charged or a refusal to perform them.

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

#80

Post by skwb »

willwagner wrote: post #74
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.

I've heard this many times before and don't doubt thats the way doctors feel but it's a little like not monitoring production because you don't want developers chasing down minor production issues.

Except there's an entire literature of false positives and the costs associated with these detections [1]. Costs here include not only direct financial costs of potentially unnecessary surgical procedures, but include everything to additional complication due to treatment and patient emotional grief/loss of earnings due to aggressive care.

The lesson a lot of people who are not familiar with public health is that you need to sorta take the long view for these things since we don't make rational decisions.

To bring back your analogy, it's then sorta like requiring an all hands meeting every time your IDE catches a typo. It's still monitoring a something that MAY cause a problem in the future, but to a good enough degree the costs associated with monitering may not be relevant to your actual end goals.

[1]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3079487/

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