4mm sessile polyp found at appendiceal orifice. Biopsies and result was precancerous. What does this mean for me?

Question

A 4mm sessile polyp was found at my appendiceal orificle. It was removed during colonoscopy. For 3mths, I have had constant bloating(looked like I was 6mths pregnant), lack of appetite, nausea, vomitting, severe abdo pain, severe constipation. It was biopsied. I was told it was precancerous. Is this bad, where it was found? What is install for me in the future. I also was told that I will have to have another colonoscopy done in 5years time, Why?