Personal experience. A few years ago my prostate enlarged relatively suddenly, to the point of making urination difficult. My doctor had no idea why, but it eventually dawned on me that I had recently been eating a lot of scrambled eggs, scrambled in a Teflon-coated skillet. I replaced it with a ceramic nonstick skillet, and the problem went away.

If you want absolute proof an anecdote won't satisfy you, but it's plenty of evidence for me. Look at the cost/risk calculation. The cost of a ceramic pan is on the order of $35; the cost of getting cancer is potentially quite large. There doesn't have to be a very large probability that Teflon causes cancer before it's not worth taking the chance.

That doesn't even begin to prove anything about cancer specifically. If it went away just like that, it wasn't cancer.

What if ceramic pans cause cancer?

Look. It takes science a long time to settle all these questions with rigorous research. In the meantime we all have to make decisions in our lives with imperfect, incomplete information. Dismissing all reports of potential risks until there is incontrovertible proof of danger is foolish; doing so out of some misguided fealty to Science and Progress is arrogant.

Downvote all you want, but you're not going to get me to stop posting anecdotes when I think they're relevant. Yes, their probative value is limited; I even acknowledged this in the post! But it isn't zero, and in a world of limited and often conflicting information, sometimes it's the best we can get.

Ceramics don't break down at temperatures encountered in cooking. Teflon does. The only question is whether the breakdown products are bioactive.

Did you even read the second paragraph?

Skepticism is a valuable thing, but it is not an unerring guide to truth. You need to be less credulous of your skepticism.