I Had Colon Cancer When I Was 42 And My

I had colon cancer when I was 42 and my sigmoid colon was resected. Have had many colonoscopies and many polyps since then , I am now 68. I had a colonoscopy last week and had two polyps removed one in the acsending and one in the descending. The one in the acsending showed high dysplasia , the other one was fine. Doctor also found a very large growth which he thought was a lipoma just where the colon makes the first turn. Upon biopsy it was discovered to be another polyp , adenoma, no dysplasia. The doctor has recommended I have another colonoscopy in three months to make sure all of the high dysplasia polyp was removed and he is going to try to remove the very large polyp but may not be able to , and I may have to have surgery. What are your thoughts on this treatment plan?