4 ms·

I’ve seen people bring up the whole “increased false positive rate” which is totally understandable but I don’t get how this couldn’t be a potential preventativ

I’ve seen people bring up the whole “increased false positive rate” which is totally understandable but I don’t get how this couldn’t be a potential preventative diagnostic tool to be combined with annual physicals. Eg that unless something is obviously wrong you wouldn’t action based on any findings from a full body scan; instead you would retain the record and repeat the scan 12-24 months later. Compare anything notable for growth or other irregular change, rinse and repeat. I would imagine that would greatly decrease the amount of pointless imaging and biopsy done. There would certainly still be some done but is that not the case now? I would imagine this is downplayed because us insurance companies are generally not huge fans of expensive preventative care procedures with little evidence base (and to the last point, fair). And additionally I’d imagine physicians and radiologists have some worry about the potential liability of things being incorrectly being labeled as benign or to be monitored and turning into malpractice claims. So the evidence base gets established by rich people who can afford to cut insurance out of the equation and hire physicians that are open to these kinds of procedures. Unfair and something I’ll be very bitter about if I ever die of a cancer that could have been detected earlier if I was lucky enough to get imaged in the area for whatever reason.

KingMachiavelli 3y ago
> I would imagine this is downplayed because us insurance companies are generally not huge fans of expensive preventative care procedures... Sure this but also: the evidence does exist and it will be a huge expensive, inconvenience, and maybe dangerous unnecessary tests/surgery for >90% of the population. Really someone has to do the math to determine the inflection point; X% of people will get some early cancer/positive result found early, Y% will get a false-positive and undergo expensive and unnecessary procedures, and Z% will still get a false result but have cost some amount of money and time. From a public health perspective, this is unlikely to be the best-next-thing because so many people die from more preventable diseases/things or lack access to health care at all. Is it a obvious service for the upper class in SF? Certainly, because the market thinks they are 5-30x more valuable than the average person so 2.5k is nothing to be extra certain of their survival. Does that sound weirdly dystopian? Sure, but it is just moving your chance of living (for the next year as our unit) by 0.00001% or less. Most people would not spend 2.5k on a 1/100k outcome.
timr 3y ago
> Eg that unless something is obviously wrong you wouldn’t action based on any findings from a full body scan; instead you would retain the record and repeat the scan 12-24 months later. Compare anything notable for growth or other irregular change, rinse and repeat. I would imagine that would greatly decrease the amount of pointless imaging and biopsy done. There would certainly still be some done but is that not the case now? The problem is birds vs rabbits vs turtles (I didn't invent this; it's a classic metaphor [1]). For any given finding on an MRI, they're going to be, tautologically, in one of three categories, in descending order of frequency: * turtles (i.e. slow growth tumors). Most people of a certain age have them, and they'll never be an issue. MRIs will find them. You can't know they're turtles. * rabbits (faster-growth, non-metastasized tumors). Maybe we can catch these, because they're slower than birds, and maybe can make a difference. Everyone wants to believe they're finding rabbits, but just because of the nature of the distribution, they're most likely finding turtles. * birds (i.e. fast metastasizing tumors; think days or weeks). This is what you want to catch, because they're metastasizing. They're deadly. They're rare. You'd like to catch these before they fly away, but how often are you going to run an MRI? Daily? Asymptomatic screening almost always catches turtles, sometimes catches rabbits, and rarely catches birds. You can't tell the difference from a single scan...so when do you choose to go further? At what cost? [1] https://lactobacto.com/2018/02/13/viewing-cancers-as-birds-rabbits-and-turtles/ https://lactobacto.com/2018/02/13/viewing-cancers-as-birds-r... [1] https://www.northcoastjournal.com/humboldt/cancer-part-2-turtles-birds-and-rabbits/Content?oid=12850085 https://www.northcoastjournal.com/humboldt/cancer-part-2-tur... [1] https://www.thedailybeast.com/all-these-cancer-screenings-probably-wont-save-your-life https://www.thedailybeast.com/all-these-cancer-screenings-pr... I included that third link -- even though it's from the Daily Beast -- because it really drives home the practical implications of the metaphor. Consider this: > In 2012, Archie Bleyer and Gilbert Welch published a study in the New England Journal of Medicine titled, “Effect of Three Decades of Screening Mammography on Breast-Cancer Incidence.” They found that, with the advent of screening mammographies, the incidence of breast cancer in the U.S. had doubled. For every 100,000 women screened, the number of women diagnosed with breast cancer had increased from 112 to 234. At the same time, the number of women presenting with late-stage breast cancer (the kind that often results in death), decreased from 102 to 94 (per 100,000). In other words, only eight of the 122 women diagnosed with breast cancer appeared to benefit from the screening. Eight. The others had been treated with mastectomy, radiation therapy, and chemotherapy without clear benefit. This is a common story in the world of cancer diagnostics.

KingMachiavelli 3y ago

> I would imagine this is downplayed because us insurance companies are generally not huge fans of expensive preventative care procedures... Sure this but also: the evidence does exist and it will be a huge expensive, inconvenience, and maybe dangerous unnecessary tests/surgery for >90% of the population. Really someone has to do the math to determine the inflection point; X% of people will get some early cancer/positive result found early, Y% will get a false-positive and undergo expensive and unnecessary procedures, and Z% will still get a false result but have cost some amount of money and time. From a public health perspective, this is unlikely to be the best-next-thing because so many people die from more preventable diseases/things or lack access to health care at all. Is it a obvious service for the upper class in SF? Certainly, because the market thinks they are 5-30x more valuable than the average person so 2.5k is nothing to be extra certain of their survival. Does that sound weirdly dystopian? Sure, but it is just moving your chance of living (for the next year as our unit) by 0.00001% or less. Most people would not spend 2.5k on a 1/100k outcome.

timr 3y ago

> Eg that unless something is obviously wrong you wouldn’t action based on any findings from a full body scan; instead you would retain the record and repeat the scan 12-24 months later. Compare anything notable for growth or other irregular change, rinse and repeat. I would imagine that would greatly decrease the amount of pointless imaging and biopsy done. There would certainly still be some done but is that not the case now? The problem is birds vs rabbits vs turtles (I didn't invent this; it's a classic metaphor [1]). For any given finding on an MRI, they're going to be, tautologically, in one of three categories, in descending order of frequency: * turtles (i.e. slow growth tumors). Most people of a certain age have them, and they'll never be an issue. MRIs will find them. You can't know they're turtles. * rabbits (faster-growth, non-metastasized tumors). Maybe we can catch these, because they're slower than birds, and maybe can make a difference. Everyone wants to believe they're finding rabbits, but just because of the nature of the distribution, they're most likely finding turtles. * birds (i.e. fast metastasizing tumors; think days or weeks). This is what you want to catch, because they're metastasizing. They're deadly. They're rare. You'd like to catch these before they fly away, but how often are you going to run an MRI? Daily? Asymptomatic screening almost always catches turtles, sometimes catches rabbits, and rarely catches birds. You can't tell the difference from a single scan...so when do you choose to go further? At what cost? [1] https://lactobacto.com/2018/02/13/viewing-cancers-as-birds-rabbits-and-turtles/ https://lactobacto.com/2018/02/13/viewing-cancers-as-birds-r... [1] https://www.northcoastjournal.com/humboldt/cancer-part-2-turtles-birds-and-rabbits/Content?oid=12850085 https://www.northcoastjournal.com/humboldt/cancer-part-2-tur... [1] https://www.thedailybeast.com/all-these-cancer-screenings-probably-wont-save-your-life https://www.thedailybeast.com/all-these-cancer-screenings-pr... I included that third link -- even though it's from the Daily Beast -- because it really drives home the practical implications of the metaphor. Consider this: > In 2012, Archie Bleyer and Gilbert Welch published a study in the New England Journal of Medicine titled, “Effect of Three Decades of Screening Mammography on Breast-Cancer Incidence.” They found that, with the advent of screening mammographies, the incidence of breast cancer in the U.S. had doubled. For every 100,000 women screened, the number of women diagnosed with breast cancer had increased from 112 to 234. At the same time, the number of women presenting with late-stage breast cancer (the kind that often results in death), decreased from 102 to 94 (per 100,000). In other words, only eight of the 122 women diagnosed with breast cancer appeared to benefit from the screening. Eight. The others had been treated with mastectomy, radiation therapy, and chemotherapy without clear benefit. This is a common story in the world of cancer diagnostics.