My Husband Started Having Pain On His Right Side Going

My husband started having pain on his right side going towards his belly button. Along with this pain is a burning and he says he cant stand to have his clothes rub against it. It says he also has a feeling of wanting to scratch but knows it will hurt. When given an ultra sound, the tech said she couldn't find his appendix. So the doc now is recommending a colonoscopy. I'm very worried.Hes in relatively good health. Could it be colon cancer?