Gallbladder Polyp

I have a gallbladder polyp 4mm in size. Does not appear to be Pedunculated, nor segmentally distributed. Concentric narrowing or constriction of the gallbladder lumen does not appear to be present. There are no stones, however there is light transient pain/aching emanating from the gallbladder area. The wall is at the upper end of normal (4mm). Blood & unpine normal.
Questions:
1. Is it likely this could be pre-cancer?
2. Do such polyps ever go away?
3. What causes thinkening of the wall?
4. What are the normal limits of the wall?

Thank you. I appreciate your time and help.

[CalGal]

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