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New Radiotracer Can Identify Nearly 30 Types of Cancer

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Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#41

Post by phkahler »

nkrumm wrote: post #18
legohead wrote: post #5

Anyone have any experience getting tested for cancer when marked as "healthy"? I contacted my PCP and some other random places asking to get a cancer screening and nobody would give me the time of day - "that's not done". At most they said they would do a blood test which checks for a couple types of cancer. I asked if I could get a CT and have a professional go over it. nope. But something like this tracer is what I…

MD here. It's "not done" because it could hurt you. Here's the Bayesian argument: - Let's assume a lab test (or imaging test) has a 1% false positive rate and 100% sensitivity (that would be pretty good for many tests and imaging modalities!). - The cancer you screening for has a 1% incidence as well (low-ish, for the sake of argument). - Therefore the chance that a "positive" scan would be due to a false positive or…

Wouldn't there also be risk from injecting radioactive tracers? And of course any CT radiation.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#42

Post by docker_up »

Nasrudith wrote: post #37
docker_up wrote: post #28

Earlier quoted context omitted.

Maybe figure out a better way to verify that doesn't require biopsy? Maybe use machine learning in conjunction with better data? I don't know enough but there must be other techniques we could devise that don't require major invasive surgery every single time. Just sitting on our hands on this information and letting people die is the worst decision. We need to improve our technology to get better results, not throw…

Well the ways that don't involve surgery are themselves less accurate heuristics with false positives. How can they calibrate without being certain if it is a true or false positive or negative? Better imaging is an option but that often falls into dangerous in itself or easier said than done like say trying to do detection of cancer by scent. Machine learning is fundamentally GIGO and tends to learn smartass shortcu…

This type of attitude is typical, where one likes to dismiss new ideas and keep status quo instead of coming up with new ideas or innovations.

The point is that there is an opportunity for the Steve Jobs of health care to come up with a way, a new innovative novel way, for classification of tumors to be improved without needing biopsy. Once we have that, then we can take tests to our heart's content. Right now, the attitude of "we shouldn't have people take tests and detect cancer early because our current method of determining if they are cancerous would make it too hard" isn't acceptable.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#43

Post by superdimwit »

madengr wrote: post #23
legohead wrote: post #5

Anyone have any experience getting tested for cancer when marked as "healthy"? I contacted my PCP and some other random places asking to get a cancer screening and nobody would give me the time of day - "that's not done". At most they said they would do a blood test which checks for a couple types of cancer. I asked if I could get a CT and have a professional go over it. nope. But something like this tracer is what I…

A CT is about 1 rem of exposure. It takes 2500 rem to cause a cancer (the linear approximation). So every 2500 CT scans you have given someone cancer.

...this assumes we're all the same person....

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#44

Post by layoutIfNeeded »

madengr wrote: post #23
legohead wrote: post #5

Anyone have any experience getting tested for cancer when marked as "healthy"? I contacted my PCP and some other random places asking to get a cancer screening and nobody would give me the time of day - "that's not done". At most they said they would do a blood test which checks for a couple types of cancer. I asked if I could get a CT and have a professional go over it. nope. But something like this tracer is what I…

A CT is about 1 rem of exposure. It takes 2500 rem to cause a cancer (the linear approximation). So every 2500 CT scans you have given someone cancer.

Use MRI then.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#45

Post by pkaye »

asdf21 wrote: post #16
sjg007 wrote: post #11

Earlier quoted context omitted.

The Iatrogenic risk is too high. CT and MRIs have false positives or reveal benign tumors/conditions that have to be investigated which result in additional testing, surgery etc... So in the absence of symptoms or known genetics / family history it is just not done. But fear not, in the next 20 years we will likely have blood based tests for finding some early cancers though. You should ask yourself why do you want t…

Shouldn't everyone want to be checked for it? I spend 10000x more time and effort monitoring the health and performance indicators of my servers compared to my body, it's astoundingly ignorant that we aren't more honed in on early detection for all sorts of issues.

Being on dialysis, I get around 20 blood tests every month. Waiting for the results is nerve-wracking because I have a few tests that are borderline and I'm expecting the worst. There is also some random fluctuation which can cause me worries. The results are certainly useful to stay healthy but at the same time, for a day or two around the test time, I just can't concentrate on plan for anything.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#46

Post by skybrian »

docker_up wrote: post #42
Nasrudith wrote: post #37

Earlier quoted context omitted.

Well the ways that don't involve surgery are themselves less accurate heuristics with false positives. How can they calibrate without being certain if it is a true or false positive or negative? Better imaging is an option but that often falls into dangerous in itself or easier said than done like say trying to do detection of cancer by scent. Machine learning is fundamentally GIGO and tends to learn smartass shortcu…

This type of attitude is typical, where one likes to dismiss new ideas and keep status quo instead of coming up with new ideas or innovations. The point is that there is an opportunity for the Steve Jobs of health care to come up with a way, a new innovative novel way, for classification of tumors to be improved without needing biopsy. Once we have that, then we can take tests to our heart's content. Right now, the a…

Presumably none of us here are inventors of new medical technology. We are just amateurs talking about this casually on Hacker News. Saying it's "unacceptable" doesn't change anything from either the doctor or patient's point of view. Until the new tech comes along, we need to accept the limitations of what we have now.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#47

Post by lonnyk »

iooi wrote: post #35
asdf21 wrote: post #21

Earlier quoted context omitted.

Hospitals don't want people to "pay themselves" when they can bill insurance companies 10x as much.

Not sure why you think that, hospitals charge insurers a lot less than their sticker price. Pricing is usually done as multiples of what Medicare pays, so insurers will build their network and usually have a cap at 2x Medicare. If you are taken to an out-of-network hospital during an emergency, the hospital can charge their regular prices, although this usually gets negotiated down for extended in-patient stays. As a…

In my experience self pay is billed at Medicare rates. But I do imagine mileage will vary.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#48

Post by orr721 »

Randypea wrote: post #29
lipman wrote: post #15

Earlier quoted context omitted.

Thanks for sharing. You got FDG PET ("older") as well as FAPI? Are you in the US? Curious if FAPI is already in wide use.... does FDG not work that well for NET ?

I am in the US and FDG PET does not work for NET. The "older" scan was Pet radiolabeled with indium-111. Comparison is here: http://prntscr.com/o02jsg Left is the newer scan, which uses Gallium 68. The primary tumor is uppermost right side, liver metastasis is left side, and small lower lighted up areas are lymph nodes. All will be removed soon. Lit up area below is the radiotracer in my bladder before urinating. :-)

Strange to see images from my specialty here on HN, but no. On the right hand side you have a classic planar OctreoScan (and from posterior view at that). What you have on the left side is a 68Ga-DOTA-(TOC/NOC/TATE) scan, not the new 68Ga-FAPI scan which I believe is only available in Heidelberg, Germany for now. While 68Ga-DOTA-(TOC/NOC/TATE) are probably not as good as 68Ga-FAPI (we don't know that yet, pending research) it is markedly better than OctreoScan, especially for small primary lesions, as is often the case in NETs. Source: I am an MD specialized in nuclear medicine.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#49

Post by orr721 »

lipman wrote: post #30
Randypea wrote: post #29

Earlier quoted context omitted.

I am in the US and FDG PET does not work for NET. The "older" scan was Pet radiolabeled with indium-111. Comparison is here: http://prntscr.com/o02jsg Left is the newer scan, which uses Gallium 68. The primary tumor is uppermost right side, liver metastasis is left side, and small lower lighted up areas are lymph nodes. All will be removed soon. Lit up area below is the radiotracer in my bladder before urinating. :-)

Good luck with the surgery! You probably got Octreoscan which is used for NET - it's SPECT imaging which is generally worse that PET, but (until now) there wasn't a good PET tracer that works in NET. Awesome to hear a story of how this new tracer could really help patients.

Sorry, this is not true. 68Ga-labelled DOTATOC, DOTANOC, and DOTATATE are used diagnosis and therapy of NETs for more than 10 years. They are widely available in Europe and in some major US centers. If the new 68Ga-FAPI will be better remains to be seen, I suppose the Heidelberg group will publish some research soon.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#50

Post by mbrundle »

hsavit1 wrote: post #7

Have been chatting with a radiation oncologist about this. His response: "imaging appears to be the same as F18-FDG-based PET. Just a bit more convenient since the patient doesn't need a normal blood sugar. And prob 2-10x the price"

At first glance, this new tracer seems to yield a lower normal tissue uptake, and the reduced background signal could make it easier to locate tumours. FDG gets taken up by several organs inc heart and brain, whereas this tracer doesn’t appear to do so to that extent.
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