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Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

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Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#21

Post by RyJones »

maxxxxx wrote: post #10
hackeraccount wrote: post #6

Earlier quoted context omitted.

"investigate further" is the sticking point. You're swimming in the ocean and notice something beneath you. Is it a friendly dolphin or a dangerous shark? Do you hold your breath and do a deep dive to figure out which it is? Keep in mind the deeper you go the greater the chance that you'll drown. It's a strained analogy but I think it gets at the problem. What if you dive a little bit deep - some minor test - and sti…

“You're swimming in the ocean and notice something beneath you. Is it a friendly dolphin or a dangerous shark? Do you hold your breath and do a deep dive to figure out which it is? Keep in mind the deeper you go the greater the chance that you'll drown.” Does it really make a difference what it is? Will you do anything differently?

I ask this question about metrics constantly. "If you had this information a year ago, what decisions would have been different?"

It usually ends in dropping the request for another metric

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#22

Post by scottlegrand2 »

What this and many other similar situations argue for IMO are better blood screens for cancer biomarkers.

For it turns out even with early detection, metastasis has already happened. It's just that those metastasized cancer cells take a long time to grow.

I mean the doctor is right, but it sure sucks to be one of the people who really has cancer and you skipped the screening, no?

https://www.sciencedaily.com/releases/2016/12/161214145615.h...

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#23

Post by VikingCoder »

KingMachiavelli wrote: post #12

Classic base rate problem, the rate of lung cancer rate is low compared to the false positive rate. It seems that one option is to follow up with a second scan 3-6 months latter and see if the tumor has increased in size. However there probably serious liability issues with this approach even if it means you're still catching the cancer earlier on average compared to waiting for physical symptoms. I'm curious how cou…

Also, detection only really matters if the treatments are effective.

If you can detect Stage 4 lung cancer one week earlier, it probably does very little to improve the quality of life.

:(

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#24

Post by astura »

aitchnyu wrote: post #17

What does a false positive look like to a doctor, and how will it not harm the organism? I can't imagine a cancer that can be ignored safely, nor an early stage treatment that is counterproductive.

So the old thought about cancer was "every cancer will grow and kill the patient so we always want to find the cancer early and treat it before it spreads"

Turns out that's not accurate, and its complicated, and we are still learning.

There's three types of cancer, birds, turtles, and rabbits. (I didn't make up this terminology, see links)

The birds have already flown away and left the barnyard, early detection isn't going to help.

The rabbits need to be contained before they hop away, if we shut the barnyard gate early enough we can prevent their escape. These are the cancers where early detection is useful and saves lives.

The turtles just chill out, moving so slow that they never escape. These cancers cause no symptoms and will not go on to ever harm the patient and may even resolve themselves over time. Finding turtles is bad, treating turtles causes very serious side effects (cancer treatment isn't exactly benign), wastes time and money, causes anxiety, and doesn't reduce mortality one bit.

We've discovered there's a lot of turtles out there.

Of course, once we find early stage cancer we usually treat it like its a rabbit, even if its destined to be a turtle, because a lot of the time we can't tell the difference.

South Korea is finding this out the hard way, aggressive screening for thyroid cancer has produced a TON of thyroid cancer patients (15-fold increase (!) over the past 20 years) but ZERO reduction in thyroid cancer mortality.

https://sciencebasedmedicine.org/a-skeptical-look-at-screeni...

https://fivethirtyeight.com/features/the-case-against-early-...

https://www.skepdoc.info/a-skeptical-look-at-screening-tests...

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#25

Post by frontloadpro »

astura wrote: post #18

>Lazris says he shows the theater diagrams to many of his patients and gets a wide range of responses. Some patients, he says, point at one of the three blackened seats and say, " 'That's probably me. I'm not taking any chances, I'm getting this test.' " >"Other people," he says, "will see [the same diagram] and will say, 'Are you kidding me? I'm not going for that; that's not worth it.'" >But in either scenario, Laz…

Start calling them Physicians.

It's important to break up the medical field by service.

Physicians are drug dealers and the literal key to getting insurance paid for.

Doctors of Physical Therapy do not perscribe medication, but are the experts in muscle and skeletal matters.

Primary Care Physicians are this weird beaurcratic step in our healthcare process.

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#26

Post by robotrout » 

    Welch says, "but [can also] find cancers that were never 
    going to matter."  That's because some cancers grow 
    slowly and never become dangerous, he says.
This exact same phenomenon is already occurring with breast cancer. Everybody is a "breast cancer survivor" these days, because they keep finding these turtle tumors that were never going to be a problem. If you look at mortality rates between those who screen early and those who don't, they are the same.

https://link.springer.com/article/10.1007/s10549-018-4691-4

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#27

Post by dontreact »

False positives will be much more rare in practice with the new guidelines used (Lung RADS) which cut false positives by 50% or more while mostly preserving sensitivity.

That doctor should really update his diagram to reflect the current standard of care for lung cancer screening. Using the false positive rate from the 2011 study is intellectually dishonest!

In addition the amount of lung cancer deaths prevented was doubled (!!) in a recent European study by tracking patients for 5 years instead of 3 years.

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#28

Post by athenot »

maxxxxx wrote: post #7

This sounds familiar. I have watched now quite a few people go through serious diseases. One pattern I saw was tests, tests and more tests. A lot of them very expensive, time consuming and painful. But when you ask what they will do with the test results there often is silence. To me it looks like they are doing something because “we need to do something”. Reminds me a little of data collection practices at companies…

As a patient (or a patient advocate for a loved-one), anytime a test is proposed it is important to ask what actionable information can come out of it. Basically look 2 steps ahead.

Some tests will help confirm a course of treatment, or propose a new one. But what if that treatment is something you've already decided you won't do? For example in an older patient too old for a surgery or a baby that you've already decided you'll keep.

But you are right, some tests are ordered out of a desire to show that "something is being done". It's important to talk with the doctor about the cost (not just money but pain & recovery) and benefit. Everything is a tradeoff.

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#29

Post by skullborg »

nimbius wrote: post #11

I wonder if this is a "dont waste your time" issue coming from management? As an anecdotal example, Im an engine mechanic who routinely sees older trucks from the 80s and 90s. mostly idler/pitman arm replacements, tires, diff fluid, etc... on these which is expected as many are pushing a million miles or more. I had a 1981 International S1700 limp into my garage one day with a misfire problem due to long, long overdu…

Do share more stories on working on old trucks! I have a '99 Ford with a 7.3, and everyone's saying it's not worth fixing, but I just like keeping it on the road...

Re: Why Some Doctors Hesitate to Screen Smokers for Lung Cancer (2015)

#30

Post by astura »

thebeefytaco wrote: post #13
maxxxxx wrote: post #7

This sounds familiar. I have watched now quite a few people go through serious diseases. One pattern I saw was tests, tests and more tests. A lot of them very expensive, time consuming and painful. But when you ask what they will do with the test results there often is silence. To me it looks like they are doing something because “we need to do something”. Reminds me a little of data collection practices at companies…

Cancer runs pretty deeply in my family, and I had read the same about breast cancer screenings years ago, re: false positives causing more harm than good, so it'd make sense to see the same trends for other cancers as well.

As far as breast cancer screening goes, the recommendations are for the general population; woman with a family history or other specific risk factors may benefit much more from screening than the general population and/or have different intervals than the general population. This is why communication with physicians is so important.
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