My Brother Died In 2007 From Colon Cancer. Every Year

My brother died in 2007 from colon cancer. Every year I have had a colonoscopy. So far they have all been good until this one I took on 08/10/15. I was told they removed a very large poly(s). Is this normal and how could I grow one this large in one year. I am waiting on the results of my biopsy, it says that it was found in the sigmoid colon (211.3) I am very stressed waiting. Can you give me any answers or help ease my mind some what. Thank you! Mary