Comment by majorchord

There's a theory that the first-stage cancer is way more common than we think, it's just doesn't develop further most of the time, cause no symptoms and remains undiagnosed throughout the lifetime.

There's some support for this view because agressive screening for thyroid and prostate cancers increases the number of surgeries a lot but doesn't seem affect the mortality rates.

Risks from a surgery are non-negligible, if you perform it to treat a low-risk condition it may be a net loss in the end.

So you're technically right about the "early-detecting" part, but the "much easier to treat" step is problematic because it's unclear what a net-positive treatment looks like for low-risk cases. Probably it comes down to yearly monitoring of whatever was detected, not the actual treatment.

Yes, you could early-detect something, but the likelihood of this thing being life-threatening are extremely low. If you choose to manage this thing aggressively anyway, you have to undergo more invasive testing (e.g., biopsies, surgery, anesthesia, etc.) that all have small risks of catastrophic events. In most cases, the risks of more invasive testing outweigh the risks of just not pursuing any further workup.

Nothing in medicine comes for free—everything is a tradeoff.

> Isn't it possible you could be early-detecting something serious that is much easier to treat now vs when symptoms appear?

It could be. It could also be the cade that you undergo invasive surgery for something that would have never caused you problems within your life. The problem is that cancer isn‘t cancer. Even if it originates from the same tissue, some tumors behave very different from others.