if the mri scans and blood tests show strong enough evidence of a problem that will impact your life that the risk outweighs the risk of the follow-up biopsy, you should get the biopsy

if they don't you shouldn't

so either you're better off or you're no worse off

unless you have to be dealing with a doctor in cya mode

I have some familiarity with diagnostic imaging - a lot of the time with these scans there's enough to say "yes, there is something there you should definitely get checked out" but you can't make a full assessment without a biopsy. The MRI is going to find things you need to investigate further.

It'll also reveal a bunch of stuff you didn't need to know. Do you want to know about that minor slipped disc in your back that wasn't bothering you before? The nocebo effect is very real.

if investigating it further isn't worth the risk, you don't need to investigate further

this superstitious ideology that ignorance is good for you has always been popular; what's surprising is that some people still hold to it despite the industrial and scientific revolutions

knowing about the minor slipped disc in your back might be important information if it starts hurting; you'll know it isn't a metastatic bone cancer. you might also be well advised to avoid taking up olympic weightlifting

> if investigating it further isn't worth the risk, you don't need to investigate further

How do you make that call? What do you, as an eager but uneducated layman, use to decide that? You now know there's a heterogeneous cyst in your abdomen that the doctor says is super unlikely to be cancerous but it's not impossible that it could be. How do you evaluate your odds? Are you opting for the biopsy? If there's a dozen of such cysts in all corners of your body? Again, the MRI is a tool to help spot a problem, it's not going to give you the diagnosis.

> You now know there's a heterogeneous cyst in your abdomen that the doctor says is super unlikely to be cancerous but it's not impossible that it could be.

That's up to the individual to decide - blanketing people in ignorance and leaving it up to chance should not be the only option.

But you're still making decisions out of ignorance and you're biased towards worst case outcomes because it's you. People are going to make the choice out of fear and that will lead to a ton of extra procedures and those people possibly having a worse quality of life as a consequence of all the elective procedures.

I would say you're biased because it's not you. You've turned everybody into a statistic to make your decisions based on the idea that it's more important to keep your percentages in line with expectations created in a broken health care environment where reactionary medicine is preferred over preventative medicine.

How are we supposed to ever make progress here if that's your mindset? This is the medical system that fears its own incompetence so much that it would prefer to NOT have data. How silly is that? What other industry operates this way?

usually i read the wikipedia articles about the disease and the common treatments, a couple dozen papers starting from google scholar via pubmed and sci-hub, maybe a relevant medical textbook via libgen. also talk to family members and friends about the issue. you can also find papers in medical journals and the mmwr on the prevalence of possible complications from different kinds of biopsies

this takes a little longer than undergoing the biopsy, but it's enormously more pleasant, and it lets you know when doctors are ignorant or lying, which is perhaps even more important information. it's orders of magnitude easier than undergoing chemo and radiation so i don't know why 'eager but uneducated' laypeople don't always do it. maybe they're too used to living in a world without sci-hub and libgen

it's also easier when it's not the first time

it's never impossible that any part of your body could be cancerous, so 'super unlikely to be cancerous but it's not impossible that it could be' is a terrible justification for taking action

> it's never impossible that any part of your body could be cancerous, so 'super unlikely to be cancerous but it's not impossible that it could be' is a terrible justification for taking action

If you knew that you or your spouse had something that could be an issue but was unlikely to be - and it's nearly guaranteed that somewhere in your body right now you have stuff that would come back as "possibly a problem" in imaging - you'd be comfortable not taking action? I doubt that's how most people would response.

yes, i have in fact done this

i'm not here to protect most people from the consequences of their own bad decisions

> What do you, as an eager but uneducated layman, use to decide that?

Is this a trick question? I use my doctor's expertise and advice, obviously. Just like I do for any other nontrivial medical question.

This has happened to me a number of times throughout my life. I have some problem, my doctor requests a scan (or x-ray or ultrasound or...), it turns up some anomalies, and my doctor has to evaluate them to decide if they are relevant to anything. For many of them the answer is, no, they're not. Now I know that I have a cyst here and some slightly misaligned vertebræ there and ... that's fine. They weren't causing the problem I had and they're probably not causing any other problems either.

The argument that we must not look at ourselves because if we do, we'll be compelled by some mysterious force to take dangerous interventions is silly and just seems like an excuse for medical incompetence or laziness.

> strong enough evidence

This is actually a bit subtle. For example I've heard more than one radiologist claim that if you look carefully, literally anyone's body scan will contain details that could justify work up.

The fact is, if you do this broadly in a population and you work up everything you see that would justify it, some small number of people will die or suffer serious problems from complications of follow up.

This is a fundamental problem in screening technologies (of any kind) with imperfect sensitivity. You can't get away from this, so you try and be clear that the net benefit is (much) higher.

I'm not even against the idea of baseline scans, but the idea that this part is simple is naive.

that's just because the radiologists' standard for 'could justify work up' are too low

Or it's because the problem is genuinely hard. See above ('imperfect sensitivity')... the same problem exists in e.g. blood tests.

I'm no radiologist but I've seen enough of this done that I'd lean that way. Especially if you consider realistic bounds on time and additional information.

yes, of course the problem is genuinely hard, but having less information about your body makes it harder, not easier

In the abstract more information is always better. In practical healthcare with real constraints, sometimes it makes things worse globally for reason above.

Think about say a diagnostic blood test with a poor sensitivity (but better than chance) on a very rare disease. As an oversimplification: for a bound take your population * workup rate * fatality rate due to workup and you have a baseline needless death due to the screening (NB there is basically always a fatality rate). The number you are comparing to is lives saved due to earlier detection.

Better than chance means it's strictly more information always. But as policy, you shouldn't do it unless you can be extremely confident that lives saves is much larger than lives lost due to the process.

This is a bit counter intuitive, but it is a fundamental issue in a lot of healthcare policy. The real calculations are more complex but in the end it is unavoidably actuarial in nature.

i explained this in https://news.ycombinator.com/item?id=37267690 except that i suggested using a better measure than crude fatality rate, such as daly

this is not a global optimization problem; it's a local optimization problem. one person is deciding whether or not to spend their own money on an mri, or a blood test or whatever, on themself. they are the ones in the best position to do that, and for very-low-risk tests like mris it is very rare that the optimal decision is for a rich person not to get them

Well I did say the actual calculations would be (and are) more complicated. And as I said, short of availability constraints, the MRI itself isn't an issue, it's the follow up.

Ignoring the fact that in the real world due to constraints this isn't really a local optimization, if we assume infinite availability you still have a problem that low sensitivity tests lead to excess unnecessary work up risks. Your assertion that it is always easy to get good information leading to correct choices here is just incorrect and probably naive.

The trade offs you are talking about are very well known and have been studied by professionals for decades; none of them will claim it easy - for good reasons.

Note I'm not appealing to authority here. Many people can educate themselves to the degree that in a narrow area of their own healthcare they are as or more knowledgable than the average professional. However, this is not at all easy, and will require a ton of work. The cost benefit for a lot of screening etc. just isn't there; for a particularly symptomatic disease it may well be.