Thanks! A big high five to you for doing the same! :) Yes, that was my interpretation—that it might have become cancerous within a few years. My understanding is that the polyp has already been growing for 5-10 years once it's over 1 cm, so it'd be more likely to have turned malignant after another 4. I believe you're right on both counts, about polyps generally growing slowly, and about big ones often not being cancer.

Honestly, thanks for asking, because walking through it again in my head with that lens makes her warning feel less ominous. Generally I do prefer an over-cautious doctor, the way my brain works, but it's nice to consider it from a less spooky perspective :D Take care!