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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

#51
post #18

Earlier quoted context omitted.

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…

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…

”Just sitting on our hands on this information and letting people die is the worst decision.”

If the alternative is saving a few who would otherwise die, but taking away more healthy days from many others or, possibly, even killing healthy individuals because they get overtreated, not spending money on screening _now_, but instead spending money on better understanding is the rational thing to do.

And that’s exactly what we are doing. Technology advances, models get refined. Maybe, some day, statistics (and ethics committees) will decide population screening does make sense.

And it isn’t necessarily about major invasive surgery. Even small procedures, done unnecessarily often enough, may already swing the balance.

Also, in some cases knowing that you have cancer may not affect your life expectancy at all. https://en.wikipedia.org/wiki/Screening_(medicine)#Overdiagn...:

”Screening may identify abnormalities that would never cause a problem in a person's lifetime. An example of this is prostate cancer screening; it has been said that "more men die with prostate cancer than of it". Autopsy studies have shown that between 14 and 77% of elderly men who have died of other causes are found to have had prostate cancer.[

Aside from issues with unnecessary treatment (prostate cancer treatment is by no means without risk), overdiagnosis makes a study look good at picking up abnormalities, even though they are sometimes harmless.

Overdiagnosis occurs when all of these people with harmless abnormalities are counted as "lives saved" by the screening, rather than as "healthy people needlessly harmed by overdiagnosis". So it might lead to a endless cycle: the greater the overdiagnosis, the more people will think screening is more effective than it is, which can reinforce people to do more screening tests, leading to even more overdiagnosis.”

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#52
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…

I think you will have a hard time getting anyone to scan you. Currently the tests are expensive and doctors have to argue with insurance companies enough as it is, for patients that exhibit symptoms.

The default answer is that the extra scanning will increase risk to you, which really isn't true if you compare that radiation to other forms of radiation you get throughout the day. 10 millisieverts is nothing. [1] You can compensate for this easily by increasing your bodies own cell autophagy.

In the mean time, you should research anti-cancer foods and foods that cause cancer and increase cell autophagy. Preventative natural medicine has many benefits beyond just preventing and treating cancer cells. Obvious foods to stay away from are anything with sugar (and all its forms, there are many) and glyphosates (good luck with that, everything is sprayed with them). Cance cells live off glycogen and oxygen.

Anti-cancer foods include aged garlic extract, bioavailable enhanced curcumin, all the cruciferous vegetables, sulforaphane extract from broccoli sprouts, fatty fish, apples, beans, to name a few. For those with metabolic syndrome which increases risk of cancer, there is Berberine which is anti-tumor (natural alternative to the prescription metformin)

I am not a doctor. This is unpopular nutritional advice for naturally reducing all cause mortality.

[1] - https://www.fda.gov/radiation-emitting-products/medical-x-ra...

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#53

Earlier quoted context omitted.

Wow! Do you have DICOM files for that! Good thing they found all that! Good luck with all the surgery, you'll get better soon!

Yes I have all the Dicom files and put all the images on a password protected server so I can share with prospective surgeons. This really helped me find the best possible surgeon. THANKS!

Minor side note: I did that too but found that institutions were locked down and could not access my public server, and they wouldn’t accept a usb drive with the same data. They were only set up to receive FAT dvds - and I spent many, many hours duping DVD’s for doctors in their waiting rooms.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#54

Earlier quoted context omitted.

False positives can be actively harmful. Unnecessary biopsies lead to unnecessary infections and stress and such.

Cancer is also harmful, particularly if not found early.

I assume every doctor's visit sees you getting checked for every type of condition every time, or do you want your doctor to play the odds and only look for things you're likely to have?

There's plenty of harmful ways to die, and you'll find they don't check for most of them until they have a decent reason.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#55

Earlier quoted context omitted.

Yes I have all the Dicom files and put all the images on a password protected server so I can share with prospective surgeons. This really helped me find the best possible surgeon. THANKS!

Minor side note: I did that too but found that institutions were locked down and could not access my public server, and they wouldn’t accept a usb drive with the same data. They were only set up to receive FAT dvds - and I spent many, many hours duping DVD’s for doctors in their waiting rooms.

The USB thing might be a security policy in action. The DVD (and that's weird, because I think I've never seen DVDs, but lots of CDRs) is probably a historical thing related to the DICOM Supplement 19 General Purpose CD-R Image Interchange Profile standard.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#57
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"

The great advantage of these tracers is that they target actual structures over-expressed in cancers, which means they show far higher specificity than something like FDG. That means they can be used to find micrometastases, and with a different radio-label also be applied for highly targeted radiation therapy.

Source: I used to work in the Heidelberg lab that published this study.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#58
post #23

Earlier quoted context omitted.

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....

1 rem of radiation exposure causes cancer with a probability of 0.05 % according to Wikipedia[1].

It seems such a scan causing a cancer would be due to a very low probability event on a cellular level. From that point of view the above calculation looks reasonable. It is only after that when the additional macroscopic influences caused by a specific person's body/environment come into play that your point applies.

This was interesting so I started from that 0.05 % per 1 rem and did the inverse calculation. For 2500 rem this gives about 1-(1-0.0005)^2500 = 71 % probability of developing cancer. I also made a plot from 0 up to 10000 REM[2]. The incident rate seems to be pretty much approaching 100 % around 10k, so our results differ by about a factor of 4.

[1]https://en.m.wikipedia.org/wiki/Roentgen_equivalent_man#cite...

[2]https://www.wolframalpha.com/input/?i=1+-+(1+-+0.0005)%5Ex+f...

EDIT: The initially mentioned 2500 rem figure must be over a long enough time for the exposure not to cause more immediate issues than cancer.

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#59

Earlier quoted context omitted.

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

1 rem of radiation exposure causes cancer with a probability of 0.05 % according to Wikipedia[1]. It seems such a scan causing a cancer would be due to a very low probability event on a cellular level. From that point of view the above calculation looks reasonable. It is only after that when the additional macroscopic influences caused by a specific person's body/environment come into play that your point applies. Th…

Yes, long time, as 2500 would kill you quickly.

I should have said linear hypothesis. I’m going off what learned in a online physics lecture on radiation effects. Right at the beginning of this:

https://youtu.be/nDviu3DLDRk

2500 people at 1 rem each yields one cancer.

250 people at 10 rem, again 1 cancer

25 at 100 rem, again 1 cancer, but they now have ARS (acute radiation sickness). This is interesting since one would think ARS would definitely cause cancer, but it’s only 1/25, whereas 1/3 of people will develop cancer.

8.3 people at 300 rem, which is the 50% threshold for death from ARS, but still 1 cancer.

I’d think 2500 CT scans/year is a typical number for a hospital. Can they be sued for causing that single incidence of cancer?

Re: New Radiotracer Can Identify Nearly 30 Types of Cancer

#60
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…

Other comments have spoken about why random screening is a bad idea. But the real problem is the tests we have just aren’t good enough. What are you hoping to diagnose with a CT scan? If you don’t smoke, the most common cancer you’ll get is breast/prostate and colon. CT scans are close to useless for detecting those cancers (If you do smoke then there is some evidence for CT screening).

Also note that image based screening has a resolution of around 5-10mm (CT and MRI closer to 5mm, nuclear medicine closer to 10mm). Once a cancer is this size, we are already talking about over 100 million cancer cells in your body. You will need surgery, and possibly chemotherapy and radiotherapy to eliminate these cells once it gets to that size.

What you actually want is prevention, not early detection.

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