Blood test that finds 50 types of cancer is accurate enough to be rolled out • Hacker News Board

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#61

Post by jacquesm » Fri, Jun 25, 2021, 12:21 PM UTC

tarsinge wrote: post #51

jacquesm wrote: post #46

Earlier quoted context omitted.

Regularly checking people that are otherwise healthy for cancer will turn up a lot of cancer through false positives or slowly growing ones, will lead to a lot of unnecessary intervention and will in fact lead to a reduction in quality of life and lifespan. This is one of the reasons why exhaustive cancer screening (which was more costly in the past but could have been done) was not promoted, it had nothing to do wit…

> Those cancers where checkups are useful we already do regular screenings for. More like “are and useful”. Regarding your last paragraph cancer screening seems very rare except for one or two types (at least where I live), so statistically yes an annual test will miss the worst case you presented, but for the vast majority it will be a huge improvement.

For those cancers where it makes sense, yes. But typically screening is voluntary (as it should be), and there are for some cancers strong genetic indicators that a person is susceptible to a particular kind of cancer, which immediately changes the equation for that particular person tremendously in favor of screening.

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#62

Post by jacquesm » Fri, Jun 25, 2021, 12:23 PM UTC

dmitryminkovsky wrote: post #60

jacquesm wrote: post #56

Earlier quoted context omitted.

Your belief has no representation in medical science, which is mostly evidence based. A lot of data has been collected on this, studies (many) have been conducted and the general consensus is that more testing absent symptoms does not lead to improved patient outcomes. That you want to have some kind of theoretical argument in the face of this evidence might be interesting to you but it isn't to me.

Not just that, but neither GP nor anyone else in this thread seems to be mentioning the mental health implications of constantly screening for life threatening diseases. For me, and many others I am sure, this would be bad . My quality of life would suffer tremendously, to the point of likely substantial loss of mental function. And I am definitely not one of these “we all die someday” types. Far from it. It’s just t…

Yes, that's a very important point. Even regular checks for cervical cancer or breast cancer can be a huge stress factor, especially in the period just prior to the test and in the waiting period until the results are in, and even more so if the test yields a false positive.

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#63

Post by pieno » Fri, Jun 25, 2021, 12:25 PM UTC

jacquesm wrote: post #46

reacharavindh wrote: post #3

This is one of those medical revolutions that I am waiting dearly for. Facilities that are not hospitals(to avoid the risk of occupying medical devices that sick people need) built to _regulary_ check up otherwise healthy people for preventive care. Heck, I have so many alerts defined on my monitoring setup for servers to watch for signals of failure before they get too big. But, my own body is not observed until som…

Regularly checking people that are otherwise healthy for cancer will turn up a lot of cancer through false positives or slowly growing ones, will lead to a lot of unnecessary intervention and will in fact lead to a reduction in quality of life and lifespan. This is one of the reasons why exhaustive cancer screening (which was more costly in the past but could have been done) was not promoted, it had nothing to do wit…

It seems like you and GP are agreeing on the fact that right now we don’t do too many preventive checks because the cost of testing is higher than the benefits (mainly because false positives could lead to risky and invasive follow-up testing to confirm that it’s indeed a /false/ positive; and knowing that you have something sooner rather than later may not meaningfully affect the outcome of the disease; and costs of tests and trained personnel are huge).

But GP seems to be saying that they hope to see better tests in the future, that are not risky or invasive, don’t have as much false positives, and are less costly to do, so that the equation would change and we could actually meaningfully improve outcomes by doing large-scale preventive testing.

You would still likely have cases where you cannot /improve/ outcome by knowing sooner that you have a disease, but as long as you are not making matters worse and improving chances for a significant subset of people, all while keeping costs the same or even decrease costs, this seems like a great evolution.

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#64

Post by mbesto » Fri, Jun 25, 2021, 12:26 PM UTC

jacquesm wrote: post #56

ggrrhh_ta wrote: post #53

Earlier quoted context omitted.

Have heard your argument on the false positives and unnecessary interventions many times. It is not a good argument. In fact, it makes no sense. If you get a positive with an uncertainty in its accuracy, at the very least, the test is repeated. But even more, you can use the information from the investigation of the reason for the false positive to improve the tests in the first place. If we weren't humans and the un…

Your belief has no representation in medical science, which is mostly evidence based. A lot of data has been collected on this, studies (many) have been conducted and the general consensus is that more testing absent symptoms does not lead to improved patient outcomes. That you want to have some kind of theoretical argument in the face of this evidence might be interesting to you but it isn't to me.

> A lot of data has been collected on this, studies (many) have been conducted and the general consensus is that more testing absent symptoms does not lead to improved patient outcomes.

Where can I find the studies that conclude this?

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#65

Post by dmitryminkovsky » Fri, Jun 25, 2021, 12:29 PM UTC

One of my great fears in life is that employers/insurers will impose this en masse on people, causing immeasurable harm to the mental health of people who can’t handle the anxiety that this type of approach to medicine would cause. I’m definitely a big proponent of evidence-based medicine and using it to help living quality life as long as possible, but this sort of thing would just wreck my day to day existence and destroy my quality of life. I am not a server in a data center. I am a human with consciousness and emotions, the desire to live, and a fear of suffering and death.

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#66

Post by jacquesm » Fri, Jun 25, 2021, 12:31 PM UTC

pieno wrote: post #63

jacquesm wrote: post #46

Earlier quoted context omitted.

Regularly checking people that are otherwise healthy for cancer will turn up a lot of cancer through false positives or slowly growing ones, will lead to a lot of unnecessary intervention and will in fact lead to a reduction in quality of life and lifespan. This is one of the reasons why exhaustive cancer screening (which was more costly in the past but could have been done) was not promoted, it had nothing to do wit…

It seems like you and GP are agreeing on the fact that right now we don’t do too many preventive checks because the cost of testing is higher than the benefits (mainly because false positives could lead to risky and invasive follow-up testing to confirm that it’s indeed a /false/ positive; and knowing that you have something sooner rather than later may not meaningfully affect the outcome of the disease; and costs of…

Even 100% true positive rate would not guarantee improved patient outcomes with massive testing. This is grounded in a poor understanding of what improved patient outcomes are all about, which is fine with me but to see this so misunderstood is a bit disappointing.

Better tests do not automatically lead to better outcomes. They will lead to many more cancers detected, and they will lead to more interventions.

Just one example (there are many more): for many tumors the risk of the operation to excise it already outweighs the risk of the tumor itself leading to damage to the body.

The factors that govern whether an intervention is necessary are determined by the rate of growth, the risk of meta-stasis, the organ(s) affected, the stage the cancer is currently in (and here early detection would at least help to get a grip on that) and so on.

But once detected treatment is going to be the norm, and that's where the problem lies: treatments are not necessarily an improvement over having a mostly dormant cancer.

If you were to autopsy all of the cadavers from any given country for a period of time you would find a correlation with age and the presence of one or more tumors in that cadaver, even if the person never had symptoms and died of a completely unrelated cause. Treating all of these would have resulted in some of those people ending up in the morgue a lot earlier and having a reduced quality of life both from a medical and a mental health perspective.

Deciding to treat - or not - is not a simple matter.

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#67

Post by moooo99 » Fri, Jun 25, 2021, 12:35 PM UTC

horstmeyer wrote: post #45

reacharavindh wrote: post #7

Earlier quoted context omitted.

May be I have been living in a bubble. I remember doing a “annual check up” in the US about 5 years ago, and that was super basic - blood pressure, sugar, cholesterol levels etc. they didn’t even do a detailed enough bloodwork to test for allergies. Definitely not looking for any disease vectors. Now, I live in DK, and my visit to the GP would always go with my hard attempts to convince my GP that something is really…

Same for me in Germany. You are eligible to one checkup when you turn 35, that's it, lol. Otherwise you have to convince the doctor a certain check is necessary. Usually doctors don't like that very much. I would even happily pay for it myself, but I still need to convince the doctor I'm not a hypochondriac.

Thats not true. The cost of the checkup are covered once before you turn 35 and every three years for anybody above the age of 35 [1]. Still, people have to be willing to do that checkup, make an appointment by themselves and so on.

Still, seeing what is and what isn't covered by public health insurance just seems so stupid. The focus on cure instead of prevention, and that not even particularly good. It's sad to see how much money goes to waste for useless treatments with something like homeopathy while people who really need proper treatment are stuck with the cheapest option that is paid for.

[1] https://www.bundesgesundheitsministerium.de/checkup.html (German)

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#68

Post by jacquesm » Fri, Jun 25, 2021, 12:36 PM UTC

mbesto wrote: post #64

jacquesm wrote: post #56

Earlier quoted context omitted.

Your belief has no representation in medical science, which is mostly evidence based. A lot of data has been collected on this, studies (many) have been conducted and the general consensus is that more testing absent symptoms does not lead to improved patient outcomes. That you want to have some kind of theoretical argument in the face of this evidence might be interesting to you but it isn't to me.

> A lot of data has been collected on this, studies (many) have been conducted and the general consensus is that more testing absent symptoms does not lead to improved patient outcomes. Where can I find the studies that conclude this?

https://www.ncbi.nlm.nih.gov/books/NBK66205/

https://www.ncbi.nlm.nih.gov/books/NBK223933/

https://www.theguardian.com/society/2021/may/12/annual-scree...

Those are popular and accessible, the actual studies you can find through Google Scholar, SciHub or various medical publications.

This is not something where the general public - or software developers, who seem to treat cancer as a bug that needs to be fixed - are going to be very helpful, I am more than happy to trust the medical establishment with this.

What would be a game changer would be rather than improved testing something that would destroy tumors in-situ in a non-invasive manner that does not involve radiation or attempts to poison the body just this side of death.

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#69

Post by hans1729 » Fri, Jun 25, 2021, 12:36 PM UTC

dmitryminkovsky wrote: post #65

One of my great fears in life is that employers/insurers will impose this en masse on people, causing immeasurable harm to the mental health of people who can’t handle the anxiety that this type of approach to medicine would cause. I’m definitely a big proponent of evidence-based medicine and using it to help living quality life as long as possible, but this sort of thing would just wreck my day to day existence and…

One of your greatest fears in life is to be regularly checked for diseases that would end your life unless thy are detected in time?

...What?

e: you mean the emotional distress caused by the process? But that's just in your head, and it's beyond irrational. Getting checked is inherently a good thing. Even if you are extremely anxious, the people who love you want you to live - this is a psychological problem that you should work through, not one with the testing

Re: Blood test that finds 50 types of cancer is accurate enough to be rolled out

#70

Post by 11thEarlOfMar » Fri, Jun 25, 2021, 12:38 PM UTC

jacquesm wrote: post #46

reacharavindh wrote: post #3

This is one of those medical revolutions that I am waiting dearly for. Facilities that are not hospitals(to avoid the risk of occupying medical devices that sick people need) built to _regulary_ check up otherwise healthy people for preventive care. Heck, I have so many alerts defined on my monitoring setup for servers to watch for signals of failure before they get too big. But, my own body is not observed until som…

Regularly checking people that are otherwise healthy for cancer will turn up a lot of cancer through false positives or slowly growing ones, will lead to a lot of unnecessary intervention and will in fact lead to a reduction in quality of life and lifespan. This is one of the reasons why exhaustive cancer screening (which was more costly in the past but could have been done) was not promoted, it had nothing to do wit…

I see it more in the vein of vaccinations. A preventive care activity, not as a reaction to a symptom. Speaking only for myself, I am regularly screened, asymptomatically, for skin, prostate and colon cancers. That screening is a non-event for me because I grew up knowing that we will get screened on a regular basis for these cancers.

With additional asymptomatic testing, there will be false positives. Re-test using a specific test and if still positive, a biopsy. How frequently do false positives lead to unnecessary procedures with the current asymptomatic screening?

What would the rate of unnecessary intervention be, vs the rate of lives saved through early detection?