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One whole-body MRI could replace multiple cancer scans

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

#61

Post by esaym »

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?

>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

Mostly it is just how the medical industry works. A previous co-worker of mine had a wife that ran a small family practice. He was always griping about the money they spent on insurance for the place ($20k a year or quarterly, can't remember). I asked why it was so much, and case in point, he told of a story just in the prior year of a woman that came in for a knot on her breast. She was informed to come back in a month as sometimes hormones can cause them to come and go. Well they never saw her again but a year later they got a malpractice lawsuit from her since she now had breast cancer...

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

#62

Post by jmhmd »

rladd wrote: post #19
dillonmckay wrote: post #5

Earlier quoted context omitted.

If you prepay, costs around $400 to $500, but that is not involving private insurance. https://www.mdsave.com/ Not affiliated, just interesting to see prices of various diagnostics around the US.

There are others that are less expensive if you do some searching, like https://radiologyassist.com/ (depending on where you live). Also, if you call independent MRI centers they will usually give you a much lower cash price (but then insurance won't reimburse). Another point to consider is that hospital MRIs can cost 10x (ten times) more than independent MRI centers. And while we're talking about MRIs, it's importan…

Regarding gadolinium, linear agents are almost never used anymore (and shouldn't be), at least in the US. Also, macrocyclics do also deposit in your brain in very small amounts, however there has never been any negative effect from this shown to date. And lastly, gadolinium is not known to cause any kidney damage. The problem in the past (in particular with linear agents) was nephrogenic systemic fibrosis, which was shown to occur in patients with pre-existing poor kidney function, probably as a result of being unable to quickly clear the gadolinium, which could then deposit in tissues. There is very little risk (if any) of NSF with newer macrocyclic agents.

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

#63

Post by [deleted] »

paulsutter wrote: post #52
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.

You're describing a problem with the doctors, not a problem with the scans. I'm curious to understand the real motivation to avoid information. Is it something in the system, litigation risk? There are many ways to deal with incidentalomas. If full body scans were more widespread, maybe doctors would have confidence to deal with them properly. For example, watching them over time.

[deleted]

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

#64

Post by SomaticPirate »

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.

But this is exactly what an “executive scan” is. I know several CEOs who get full body scans. Two of them caught early stage cancers and credit these scans with vastly improving their prognosis.

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

#65

Post by tptacek »

DuskStar wrote: post #28
tptacek wrote: post #21

Earlier quoted context omitted.

Isn't 20 scans a day something like 15 hours of continuous, back-to-back scanning?

Are you saying that you wouldn't have your multi-million dollar imager running as much as possible?

I'm saying that it seems like a most optimistic, best-case scenario, and not the average case.

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

#66

Post by fma »

dillonmckay wrote: post #5
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?

If you prepay, costs around $400 to $500, but that is not involving private insurance. https://www.mdsave.com/ Not affiliated, just interesting to see prices of various diagnostics around the US.

I've seen Groupons for MRI scans and thought surely it must be a scam. From the reviews, sometimes they pressure you to get a package for periodic scans and use the first as a base line. But interesting indeed!

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

#67

Post by rolleiflex »

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 do receive.

A stream of known false positives is worth its weight in gold in any detection system, it's just that this specific system happens to contain squishy feely human doctors that are susceptible to short-term human 'Please don't spend more money than necessary, we're already in the red for this quarter' kind of pressures from their superiors.

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, which would counteract the temporary cost increase in chasing false positives. The fact that we don't want to eat the short term initial cost means some of those things that could be uncovered by the scan, things that could save a person from a malignant deviation, is left unseen, untreated, to its natural end.

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

#68

Post by rozza »

lighttower wrote: post #48
rozza wrote: post #30

My wife has had full body scans every 3 months for the past 3 years. She currently has multiple active sites of bone mets, from the spine to shoulders and hips. A single scan is much more convenient and keeps the oncologist up to date with the state of her cancer. In our experience sometimes a new cancer site isn't diagnosed quickly, especially if it's asymptomatic and slow growing. Having past scans and reviewing th…

What's the primary Cancer type? I'm assuming multiple myeloma?

Breast Cancer HER2+ Currently being treated with Trastuzumab and Pertuzumab every 3 weeks. Seems to be doing its job keeping down the cancer growth rate. She also used to have Zoledronic acid at the same time but that caused osteonecrosis of the jaw, so has been stopped.

Strangely, we're relatively happy with the bone mets. The two times the cancer hit soft tissue it grew alarmingly quickly. First in the breast, then when it came back and broke out the L2 vertebrae and wrapped the nerve. At least in the bone it grows slowly. When it eventually starts to break out, the next treatment is Trastuzumab emtansine, which is a chemo drug, so will have many more side effects to manage.

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

#69

Post by duxup »

petschge wrote: post #55
chongli wrote: post #23

Earlier quoted context omitted.

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?

Getting a baseline is harder than it sounds. In the case of blood chemistry that is caused by fluctuations due to time of day, time of month, season, what you recently ate and so one. In the case of MRI the problem is that internal organs shift to the point that it is impossible to automatically compare. And a experienced doctor comparing the scan millimeter for millimeter takes hours and would be very expensive. Eve…

> internal organs shift to the point that it is impossible to automatically compare

I didn't even know that is a thing, I just sorta assumed they stayed put.

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

#70

Post by a11r »

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?

Most tests are probabilistic and you have to think about the conditional probability given other indicators. Consider a urine culture for detecting UTIs. If you just get urine samples from a general population, some fraction will show positive (bacteria in the culture) falsely. It would be pointless to perform this test on the general population and to treat people that show positive . But if you perform this test conditioned on the fact that the patient is presenting other symptoms (burning sensation, fever etc.) then the same test very useful and the conditional false probability is low enough that it can be used to decide on treatment.

The same idea applies to most tests in medicine. That is why tests are mostly done conditionally.

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