<story><title>Blood test that finds 50 types of cancer is accurate enough to be rolled out</title><url>https://www.theguardian.com/society/2021/jun/25/blood-test-that-finds-50-types-of-cancer-is-accurate-enough-to-be-rolled-out</url></story><parent_chain><item><author>jacquesm</author><text>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.&lt;p&gt;That you want to have some kind of theoretical argument in the face of this evidence might be interesting to you but it isn&amp;#x27;t to me.</text></item><item><author>ggrrhh_ta</author><text>Have heard your argument on the false positives and unnecessary interventions many times.&lt;p&gt;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&amp;#x27;t humans and the uncertainty of the test is known then at the very very very least you could throw a dice to decide whether you discard or not the test result.&lt;p&gt;If more information leads to worse decisions it just means that the noise level introduced by the test is just too high. A way to reduce the noise is two amplify the signal, and a way to amplify the signal is to look for more information (other tests, other indirect measurements: i.e., look for B if A was positive, etc.).</text></item><item><author>jacquesm</author><text>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 with ability, but everything to do with outcomes.&lt;p&gt;Those cancers where checkups are useful we already do regular screenings for.&lt;p&gt;For aggressive cancers - the ones that are really problematic - you would have to do such a test too frequently to make any real difference, for instance, if you were to test annually you&amp;#x27;d be on average 6 months away from your next test, plenty of time for such a cancer to develop and kill you.&lt;p&gt;So this is not the kind of breakthrough that you may think it is.</text></item><item><author>reacharavindh</author><text>This is one of those medical revolutions that I am waiting dearly for.&lt;p&gt;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.&lt;p&gt;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 something bad needs treatment. Why can’t we observe ourselves medically and analyze that record for early signs of trouble before it becomes serious?!&lt;p&gt;All the advancement in technology in recent years, this ought to happen sooner than later.</text></item></parent_chain><comment><author>melling</author><text>Less information is better?&lt;p&gt;That would be a bit of a paradox in science.  I suppose we might take 2 steps forward and 1 step backward in the short term. As medical science advances, hopefully we can address any shortcomings from the additional early knowledge.&lt;p&gt;I noticed that pancreatic is on the list.  This cancer is almost always fatal because we can&amp;#x27;t detect it early.</text></comment>
<story><title>Blood test that finds 50 types of cancer is accurate enough to be rolled out</title><url>https://www.theguardian.com/society/2021/jun/25/blood-test-that-finds-50-types-of-cancer-is-accurate-enough-to-be-rolled-out</url></story><parent_chain><item><author>jacquesm</author><text>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.&lt;p&gt;That you want to have some kind of theoretical argument in the face of this evidence might be interesting to you but it isn&amp;#x27;t to me.</text></item><item><author>ggrrhh_ta</author><text>Have heard your argument on the false positives and unnecessary interventions many times.&lt;p&gt;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&amp;#x27;t humans and the uncertainty of the test is known then at the very very very least you could throw a dice to decide whether you discard or not the test result.&lt;p&gt;If more information leads to worse decisions it just means that the noise level introduced by the test is just too high. A way to reduce the noise is two amplify the signal, and a way to amplify the signal is to look for more information (other tests, other indirect measurements: i.e., look for B if A was positive, etc.).</text></item><item><author>jacquesm</author><text>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 with ability, but everything to do with outcomes.&lt;p&gt;Those cancers where checkups are useful we already do regular screenings for.&lt;p&gt;For aggressive cancers - the ones that are really problematic - you would have to do such a test too frequently to make any real difference, for instance, if you were to test annually you&amp;#x27;d be on average 6 months away from your next test, plenty of time for such a cancer to develop and kill you.&lt;p&gt;So this is not the kind of breakthrough that you may think it is.</text></item><item><author>reacharavindh</author><text>This is one of those medical revolutions that I am waiting dearly for.&lt;p&gt;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.&lt;p&gt;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 something bad needs treatment. Why can’t we observe ourselves medically and analyze that record for early signs of trouble before it becomes serious?!&lt;p&gt;All the advancement in technology in recent years, this ought to happen sooner than later.</text></item></parent_chain><comment><author>amluto</author><text>You’re making an unwarranted assumption: that the choice is between early detection &lt;i&gt;with current responses to detected cancers&lt;/i&gt; and no early detection at all. Optimizing the response to an early detection will give a result no worse than either of those, since the choices of what to do include doing whatever doctors did in the studies that have poor results as well as doing nothing at all.</text></comment>