Recent colonoscopy revealed - patch mucosal congestion. any medicine/diet advise please? symptoms are intermittent tightness ascending colon.

I would think the: description "patch mucosal congestion" would be an incidental, benign finding. It suggests a little swelling and perhaps prominent blood vessel in a small portion of the colon lining. This would not cause any symptoms, certainly not "tightness" in the colon (which I don't think you can feel). General colon cancer prevention is avoiding red/processed meats, refined grains/sugars, adding fiber.