How long would adenomatous colon polyp take to turn into cancer?

Depends on hx: If you have polyps the current thinking is that it takes over 5 yrs to develop a polyp and have it turn in to cancer. That is why the current reccomendation is to get a colonoscopy every 5 yrs with hx of polyps. Other genetic polyp formers such as familial adenomatous polyposis have a far more rapid cancer formation rate. Be sure to talk to your dr about the type of polyps you have and colonoscopy.

YEARS: In general 8 to 10 years. This is known as the adenoma to carcinoma sequence. This is why screening colonoscopy is recommended every 10 years to look for polyps.