Yesterday, following a challenge, I was directed to this study that suggested screening for breast cancer could save lives.
"All‐cause mortality versus cancer‐specific mortality as outcome in cancer screening trials: A review and modeling study": https://onlinelibrary.wiley.com/doi/full/10.1002/cam4.2476

Like any honest scientist I chose to read the paper and change my mind if necessary. I was disappointed to learn that this was not a RCT nor a meta-analysis of RCTs, it was a mathematical model with three "simulated" trials of screening for breast, lung and colo-rectal cancers./2

Because of the relative rarity of deaths from breast cancer it was calculated you would need a RCT of 2.6M to have the power to show an impact on all cause mortality, but the model doesn't factor in deaths from other causes from the over-treatment of over-diagnosed cases./3

The other false assumption is that breast cancer progresses through the stages in a linear trajectory that ignores the problem of interval cancers. Even if their assumptions were correct we must not forget the opportunity cost of screening 2.6M women./4

Breast cancer is 7th in the league for deaths amongst women that is topped my dementia, cardio-vascular disease and respiratory disease. I suggest we close down screening and use our scarce resources to address these greater threats./END