[munksbeer]

So if this is true, it seems that we must accept that many people will die of cancer we could have detected and cured with frequent scans, because doing frequent scans will overall cause more harm to people who didn't need treatment. So the overall death/harm rate would be worst with more frequent scans?

Isn't that then just a problem with the scan and diagnosis? With more frequent scans it seems highly unlikely that we wouldn't improve this process and end up in a better place.