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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

#31

Post by amluto »

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.

Why is this an issue with testing rather than an issue with the conditions under which treatment is given?

In other words, ISTM the problem isn’t with a full-body scan per se. The problem happens if every little thing found gets treated or tested invasively.

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

#33

Post by benaadams »

hammock wrote: post #6
sampleinajar wrote: post #4

> The average cost of a WB-MRI scan for NSCLC patients was £317 Wow! $3000+ here in the US. Ever get the feeling you've been cheated?

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.

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

#34

Post by JamesBarney »

aitchnyu wrote: post #29
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.

Why do doctors advocate less frequent scans when they see that frequent scans creates false positives? Can a metric be invented such that a doctor can make a solid decision "I'm 99% sure this wont kill you in two years" and leave the tumour alone?

I imagine there is a lot of non-optimal decision making going on the patients side because of the emotional salience of cancer, and on the doctors side because of lawsuit risk.

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

#35

Post by whatshisface »

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.

Why can't a doctor see an anomaly and decide not to chase it down based on the same reasoning that they use to not scan for it? Is there some pointless legal trap related to malpractice where the only allowable "don't operate" decision happens when the doctor decides what to test for?

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

#36

Post by jszymborski »

amelius wrote: post #32

What is the state of cancer detection through blood samples?

There are some cancers where blood biomarkers give us more information than others, but save for leukemia, I'm unaware of any that are sufficient for diagnosis.

While still widely, the effectiveness of some blood biomarkers like PSA (prostate cancer) can be controversial.

So, while I could be wrong since this isn't my area of expertise, there's a long way to go for most cancers when it comes to blood testing.

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

#37

Post by arkades »

whatshisface wrote: post #35
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.

Why can't a doctor see an anomaly and decide not to chase it down based on the same reasoning that they use to not scan for it? Is there some pointless legal trap related to malpractice where the only allowable "don't operate" decision happens when the doctor decides what to test for?

(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 enormous lookback period and an automatic “doctor loses.” It doesn’t matter if the doc made a statistically appropriate call. So docs follow-up on anything but the most unambiguously benign lesions.

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

#38

Post by snowwrestler »

ChrisLomont wrote: post #25
Someone1234 wrote: post #10

Earlier quoted context omitted.

Only 20 scans a week? A scan takes 30-60 minutes. So even if they only work 8 hour days and assume an hour for lunch/flex that's 35 scans per 5 day week. If they use it on weekends at all or run it for more than eight hours, that's just gravy. I'm not sure where you got the 20 scans a week number.

Because scans are not booked wall to wall every hour of every day. Needs more likely follow a poisson distribution with ample waits in between uses. To try and pack it that densely, with the large variation in how people show up at the hospital, would cause bottlenecks and loss of service. 20 a week is a more common number for most places. Here's actual data [1] measured on site. The usage is indeed around 50%, so th…

This is data from a hospital. In the U.S. at least, a lot of MRI scans are done in outpatient centers, scheduled well in advance, and so utilization can be much higher. This would certainly be true of prophylactic scans.

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

#39

Post by el_benhameen »

whatshisface wrote: post #35
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.

Why can't a doctor see an anomaly and decide not to chase it down based on the same reasoning that they use to not scan for it? Is there some pointless legal trap related to malpractice where the only allowable "don't operate" decision happens when the doctor decides what to test for?

I think the pointless trap is often the patient. I worry less than some but more than many, and while I usually defer to my doctor's advice to leave most of life's little lumps and bumps be, it's a challenge for me to accept the unknown. I imagine that many patients will demand answers once they know that any anomaly exists, no matter how likely the benign explanation is.

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

#40

Post by lostlogin »

hammock wrote: post #6
sampleinajar wrote: post #4

> The average cost of a WB-MRI scan for NSCLC patients was £317 Wow! $3000+ here in the US. Ever get the feeling you've been cheated?

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.

10-20 scans per day is a full days work in MRI for an 8-9 hour day. I’m an MR radiographer.
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