@FLClover
I honestly can’t remember if we talked percentages. I know that he was particularly impressed by one long term survey with a statistically large number of participants - which of course makes a difference about percentages. 4% of 100 doesn’t seem much, 4% of 10,000 is more compelling! But a lot depends on your chances of being in the 4%, which is uncertain too! He was however very much of the view that, in my case, staying on Femara was likely to prove beneficial.
As with all treatment, there’s no absolute way of knowing. I have been clear of cancer ten years - I might have been with surgery only! I’m satisfied that, again in my case, the risk justified the treatments I have had. I am also confident that if I had had miserable side effects I would probably have stopped much sooner. As @Keeping_positive1 says, there are all sorts of issues that might affect our individual outcomes. It’s what makes cancer so difficult - and presumably so fascinating for oncologists, and I don’t mean it in a guinea pig way. If I were going into medicine, it’s one of the great mysteries to be resolved.