Yearly gallbladder scan for 4 mm polyp since 2009 no changes tomorrow due for yearly how likely to suddenly change ?

1cm is cut-off: Any unknown lesion that grows, until characterized as benign, is of concern. Gallbladder polyps that double in size in 6 years certainly raise such concern. Your surgeon is likely taking your age into consideration, as well as citing a cut-off of 1cm for polyp size at which point the polyp(s) warrants cholecystectomy. Close follow-up by surveillance ultrasounds is recommended at the very least.

See below: I would think very unlikely to change if it's been stable since 2009