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

#241

Post by tnel77 » Fri, Jun 25, 2021, 4:10 PM UTC

plank_time wrote: post #147

TaupeRanger wrote: post #138

Earlier quoted context omitted.

You say "utterly wrong" and yet you clearly have no idea what you're talking about and have never even approached the field of health policy. Screening has to PROVE that it makes people live longer or better, just like any other intervention. It is not the case that screening is automatically good, otherwise we would be giving 20 year olds colonoscopies. Just because you find something, doesn't mean you've helped the…

We don’t give colonoscopies to 20 years olds because it’s an expensive, invasive test with a low rate of cancer. We don’t give mammograms to under 40 year olds these days because the same and it’s notoriously inaccurate. We give blood glucose level tests and cholesterol tests to everyone every year at the physical because they are cheap and easy to administer. Even though the effects of both may take decades to have…

For every genuinely smart person on HN, there’s a handful of Google warriors who hardly know what they are talking about. I guess that’s not unique to HN, but it can be aggravating just how many commenters can be so “know-it-all” with their comments.

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

#242

Post by avion23 » Fri, Jun 25, 2021, 4:11 PM UTC

rackjack wrote: post #190

fallingknife wrote: post #186

Earlier quoted context omitted.

> but doctors can't always predict this and aren't perfect decision making machines So mass screen healthy people, collect the data, run models, and get better at it. People like you would rather not try, and this is the same reaction I get from doctors. Applying the same tech that we use to improve ad targeting to disease prediction is a no brainer to anyone whose cushy job doesn't depend on the current medieval sta…

Same vibe as "I would just simply..." What do you think the entire medical, pharmaceutical, bioinformatic, etc. industries have been doing for decades? Are you really so arrogant to think that other people are too lazy and stupid to think of your brilliant idea and that you are simply more intelligent than everybody else? Do you really think people haven't been trying?

> Are you really so arrogant to think that other people are too lazy and stupid to think of your brilliant idea and that you are simply more intelligent than everybody else?

Not OP, but yes, I do.

I've had some runins with the health system. At least the parts that I've seen are worse than the dark ages. Especially endocrinologists have absolutely no clue what they are doing. The ones I met don't even have superficial knowledge about their full-time job which they've performed for ~20 years.

And yes, this sounds arrogant. I've tripple checked whether I'm just tripping. Their knowledge is not simply outdated, but never correct to begin with.

I think it's a cultural problem which shows in a lot of areas. Medicine doesn't value human life as much as f.e. air transport

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

#243

Post by radu_floricica » Fri, Jun 25, 2021, 4:13 PM UTC

vidarh wrote: post #41

radu_floricica wrote: post #16

Earlier quoted context omitted.

I never understood this. I mean I totally get the concept, but I don't get how it came to influence policy. Put it like this: how many people are you willing to kill to make sure people don't find out they're sick? Because that's what it boils down to. And it sounds... sociopathic.

How many people are you willing to kill with too excessive testing programs? Because that is part of the equation too. It's easy to ignore because chances of harm from non-invasive-ish testing like a blood test is low. The problem is that it compounds quickly. Consider: * For a rare condition you need a lot of tests to find them. Let's say you look for something that 1 in a million can be expected to have. * When you…

You're missing a step. There are several responses saying basically the same thing (testing kills), and more or less randomly I'm going to answer yours. All have the same step missing.

Testing doesn't kills by itself, not in numbers worth mentioning. Treatments - sure, a whole different ball game, they're positively dangerous. But between testing and treatments there should be a specialist that crunches the numbers and comes to a decision. Which, like in the mammogram example above, is not always going to be more aggressive testing.

What testing does is give you more information, which in a remotely sane system should lead to better decision making. Of course, I can imagine insane systems where, for example, the patient decides, the insurance pays and the doctor can be sued for discouraging treatments. In this particular combo you probably want to avoid doing mammograms to 20 yo, because the chance of a false positive is 1%, the chance of a true positive is 0.01%, and you end up with perverse chains leading to healthy people doing chemo. Like I said in the original comment, I GET the phenomenon. What I don't get however is how it can get even close to conventional wisdom that you want to avoid testing, as a rule. That's a particular fix to a particularly insane incentive combo, and common sense should make everybody rail against the insane incentive combo, and not act like the niche fix is actually a goal.

I can't really explain how this came to be. Maybe people stumbled on an explanation of how extra testing _may_ be harmful, and the idea was so cool that it got stripped of context and became a meme in itself.

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

#244

Post by tnel77 » Fri, Jun 25, 2021, 4:14 PM UTC

rackjack wrote: post #223

JumpCrisscross wrote: post #208

Earlier quoted context omitted.

> One and a half MILLION people whose life gets turned upside down, WRONGLY, due to a blood test Culture adapts. Getting a cancer diagnosis today is a huge deal because testing is infrequent, usually in response to a problem, and the diagnosis tends to be late and accurate. If 1.5mm healthy people get a false positive every year, the general response will be stress until a second test confirms a false positive. The l…

> Getting a cancer diagnosis today is a huge deal because testing is infrequent, usually in response to a problem, and the diagnosis tends to be late and accurate. Getting a cancer diagnosis is a "huge deal" because getting cancer is one of the worst experiences a human can go through. Getting cancer carries the weight of imminent death, obviously. But some cancers can be cured with high survival rate, so what's the…

>Getting a cancer diagnosis is a "huge deal" because getting cancer is one of the worst experiences a human can go through.

I’ve never been given a cancer diagnosis, but I’d imagine it’s much, much worse to be told you have stage 4 cancer versus stage 1. As the other person stated, the culture would adapt and people would learn to not immediately sell their house and go on a Vegas bender just because a yearly preventative test said they might, possibly, perhaps have stage 1 cancer. If you are one of the people with a false positive, you schedule a follow-up and move on accordingly.

Your position is anti-progress just for the sake of being against accidentally scaring a few people. Indeed, we should let more people develop cancer and discover it at a later stage due to a small amount of false positives. Not scaring a small amount of people is more important than revolutionizing cancer screenings.

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

#245

Post by bryan0 » Fri, Jun 25, 2021, 4:15 PM UTC

throwawaynotmd wrote: post #109

TaupeRanger wrote: post #96

Earlier quoted context omitted.

Actually you don't want this, and you are describing a nightmare scenario that everyone who studies health policy understands all too well. Mass screening of healthy people will result in extreme iatrogenics and unnecessary psychological damage and stress (which leads to physical effects as well), not to mention overwhelming the medical system. The fact is that many things that could be detected will never result in…

The argument you’re making has always bothered me because it’s hiding the ball. If finding something that otherwise carries no symptoms is best left untreated, then the fact that you found it should make no difference to the decision. The doctor should say that the best course of action is to do nothing. More information can never be harmful. If you know information is best not acted on in the abstract, then you also…

> More information can never be harmful.

This is an extremely naive viewpoint and in some situations quite dangerous.

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

#246

Post by Engineering-MD » Fri, Jun 25, 2021, 4:21 PM UTC

robocat wrote: post #214

Engineering-MD wrote: post #179

For those interested in reading the actual paper, this appears to be it (open access too): https://www.annalsofoncology.org/article/S0923-7534(21)02046... I’ve only skimmed it, but seen quite a few limitations, notably those with “non-malignant conditions at enrolment” (it would be nice to know more what that means), previous cancer or recent corticosteroids use were excluded. Additionally, it’s a case controlled tri…

> 500 people 5000 people

Yes thank you missed a zero

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

#247

Post by cronix » Fri, Jun 25, 2021, 4:24 PM UTC

One day you'll put your finger on a sensor on your phone that pricks you to get a drop of blood and analyze it right there on the spot. Kinda like square does for mobile credit card payments.

Maybe that's how you'll unlock it too, which might help with phone addiction /s

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

#248

Post by bookofjoe » Fri, Jun 25, 2021, 4:26 PM UTC

What makes this even more revolutionary to me (retired anesthesiologist) is that the methodology allows for use of Theranos-style finger-prick-size blood samples rather than IV blood draw, since fragment identity is the indicator rather than level/concentration.

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

#249

Post by rackjack » Fri, Jun 25, 2021, 4:26 PM UTC

JumpCrisscross wrote: post #225

rackjack wrote: post #223

Earlier quoted context omitted.

> Getting a cancer diagnosis today is a huge deal because testing is infrequent, usually in response to a problem, and the diagnosis tends to be late and accurate. Getting a cancer diagnosis is a "huge deal" because getting cancer is one of the worst experiences a human can go through. Getting cancer carries the weight of imminent death, obviously. But some cancers can be cured with high survival rate, so what's the…

> these cures are often brutal Heart disease is a huge deal. It ruins your life. (Maybe not in all caps.) Nevertheless, we regularly test for it, including with techniques with high rates of false positives. Few panic because almost everyone knows someone who got a false positive and didn't promptly keel over and die. If healthy adults are screened for cancer, there will be cultural memory of people who got a false p…

I don't enough about heart disease treatment to comment on the degree it ruins your life.

People already get further testing. People already get second opinions. In the time you are changing your lifestyle (a good option for helping treatment, I agree) and increasing monitoring you could already be progressing beyond treatability.

You can argue about whether it's alright to tell sub-1.5 million people each year who don't have cancer that they have cancer (I don't think it is, but whatever). But again you can't disregard the non-insignificant number of people who get false positives.

edit: Actually, not "whatever". You probably shouldn't tell sub-1.5 million people each year who don't have cancer that they have cancer.

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

#250

Post by ggrrhh_ta » Fri, Jun 25, 2021, 4:27 PM UTC

jacquesm wrote: post #204

Silhouette wrote: post #198

Earlier quoted context omitted.

So you do agree that evidence-based screening programmes can be effective then? In that case, I'm sorry but I don't quite understand the point you're trying to make here.

Yes, they can, but not in a blanket fashion where a test with a relatively high false positive rate and a relatively low sensitivity (between 18 and 50% for this particular test) is released without patient outcomes as the main driver of whether or not to apply the test absent further symptoms. Whether this test is one that can serve in that particular role is definitely not something that has already been determined…

Well. With a bad test, what is necessary is to improve the test. The argument "outcomes are worse off with more absent symptoms testing" is really saying that symptoms is more predictive than the test itself: test is positive if [symptoms & positive result] test is positive or neutral if [no symptoms & should have been screened & positive result] and test is negative if [no symptoms & should not have been screened & positive result] (notice that this does not change the outcome to not testing people without symptoms and without another reason to do so). Until the tests/decision protocols were improved to avoid false positive, this third case should be communicated to the person as a negative result of the test (if we are convinced that the overall outcome is better off if the test should not have been administered at all), but I would find that unethical and dehumanizing and I understand touches on lots of ethical issues: the stress of waiting for a result, the liability of not being an actual false positive, etc. So, I understand, that given the current state of the testing, the decision is to restrict when to do it.