5 ms·

Early detection? Whats the best way to detect cancer (money is no object) and how do we get that cost down 10x and get everyone to participate?

by mentos 4y ago

chrisamiller 4y ago
Money is absolutely an object. People are starting to do trials of early detection from circulating tumor DNA, and finding that the hit rate is alarmingly high. A decent portion of the population has some kind of malignancy, but most of these will either be cleared by the immune system, or be completely benign. Another problem is, if we detect this tumor DNA, it doesn't tell us where in the body the tumor might be. So then you're talking massive workups including while body CT scans and such for a problem that isn't going to be a problem for 99% of people. I'm not joking when I say that if rolled out as is, this has the potential to bankrupt the entire healthcare system with unnecessary procedures. To be clear, I very much think that early detection of tumors will someday be an essential part of cancer treatment. We are not there yet.
- asdff 4y ago
  >Another problem is, if we detect this tumor DNA, it doesn't tell us where in the body the tumor might be. This isn't necessarily the case. A lot of CTCs have markers that are indicative of certain cancers or tissue types of origin. Different tissues have specific patterns of gene expression even if they all have the same underlying DNA, and there are databases with thousands of samples sequenced supporting these patterns.
- Nathanael_M 4y ago
  I think the question being asked was "If money were no object, what is the best cancer detection method?", as opposed to stating that money wasn't an object. Very interesting comment, nonetheless.
- mjsabby 4y ago
  Lots of clinics in Vancouver BC fully body MRI scans that are not super expensive. I really do think we should just make MRIs cheap and then get the whole world to do them. I understand the cost, time, etc. but I still think if we can stop doing other useless stuff as humanity and do this it would be net positive.
sam537 4y ago
Look at GRAIL therapeutics. Cancer sheds DNA that can be detected and amplified. We use this sometimes to try to tell if someone will have a recurrence before scans actually show it. Sequencing is hard, and there are contaminants and difficulties calling a mutation/sequence cancerous, but I have had patients self-refer after a positive GRAIL test, no symptoms, and bam, biopsy from area of interest shows early cancer.
pella 4y ago
problems: - False-positive results - False-negative results "Mammograms are the best breast cancer screening tests we have at this time. But mammograms have their limits. For example, they aren’t 100% accurate in showing if a woman has breast cancer. They can miss some cancers, and sometimes they find things that turn out not to be cancer (but that still need further testing to be sure)." https://www.cancer.org/cancer/breast-cancer/screening-tests-and-early-detection/mammograms/limitations-of-mammograms.html https://www.cancer.org/cancer/breast-cancer/screening-tests-...
- selectodude 4y ago
  Furthermore the detection method used (x-rays) cause cancer in and of themselves.
  - Buttons840 4y ago
    https://xkcd.com/radiation/ https://xkcd.com/radiation/ lead me to believe that most x-rays only expose the person to a few days worth of background radiation. Is that accurate? And does it really matter?
asdff 4y ago
You can detect tumor cells circulating in blood for certain cancers. You can get the cost down by having these tests covered at regular intervals by insurance companies.
- throwaway12245 4y ago
  Or make it over the counter and pay the $500.

Early detection? Whats the best way to detect cancer (money is no object) and how do we get that cost down 10x and get everyone to participate?

by mentos 4y ago

Early detection? Whats the best way to detect cancer (money is no object) and how do we get that cost down 10x and get everyone to participate?

chrisamiller 4y ago

Money is absolutely an object. People are starting to do trials of early detection from circulating tumor DNA, and finding that the hit rate is alarmingly high. A decent portion of the population has some kind of malignancy, but most of these will either be cleared by the immune system, or be completely benign. Another problem is, if we detect this tumor DNA, it doesn't tell us where in the body the tumor might be. So then you're talking massive workups including while body CT scans and such for a problem that isn't going to be a problem for 99% of people. I'm not joking when I say that if rolled out as is, this has the potential to bankrupt the entire healthcare system with unnecessary procedures. To be clear, I very much think that early detection of tumors will someday be an essential part of cancer treatment. We are not there yet.

asdff 4y ago
>Another problem is, if we detect this tumor DNA, it doesn't tell us where in the body the tumor might be. This isn't necessarily the case. A lot of CTCs have markers that are indicative of certain cancers or tissue types of origin. Different tissues have specific patterns of gene expression even if they all have the same underlying DNA, and there are databases with thousands of samples sequenced supporting these patterns.
Nathanael_M 4y ago
I think the question being asked was "If money were no object, what is the best cancer detection method?", as opposed to stating that money wasn't an object. Very interesting comment, nonetheless.
mjsabby 4y ago
Lots of clinics in Vancouver BC fully body MRI scans that are not super expensive. I really do think we should just make MRIs cheap and then get the whole world to do them. I understand the cost, time, etc. but I still think if we can stop doing other useless stuff as humanity and do this it would be net positive.

sam537 4y ago

Look at GRAIL therapeutics. Cancer sheds DNA that can be detected and amplified. We use this sometimes to try to tell if someone will have a recurrence before scans actually show it. Sequencing is hard, and there are contaminants and difficulties calling a mutation/sequence cancerous, but I have had patients self-refer after a positive GRAIL test, no symptoms, and bam, biopsy from area of interest shows early cancer.

pella 4y ago

problems: - False-positive results - False-negative results "Mammograms are the best breast cancer screening tests we have at this time. But mammograms have their limits. For example, they aren’t 100% accurate in showing if a woman has breast cancer. They can miss some cancers, and sometimes they find things that turn out not to be cancer (but that still need further testing to be sure)." https://www.cancer.org/cancer/breast-cancer/screening-tests-and-early-detection/mammograms/limitations-of-mammograms.html https://www.cancer.org/cancer/breast-cancer/screening-tests-...

selectodude 4y ago
Furthermore the detection method used (x-rays) cause cancer in and of themselves.
- Buttons840 4y ago
  https://xkcd.com/radiation/ https://xkcd.com/radiation/ lead me to believe that most x-rays only expose the person to a few days worth of background radiation. Is that accurate? And does it really matter?

asdff 4y ago

You can detect tumor cells circulating in blood for certain cancers. You can get the cost down by having these tests covered at regular intervals by insurance companies.

throwaway12245 4y ago
Or make it over the counter and pay the $500.