You need a regular check-up from a gastroenterologist if you've had a past gastroenterological issue. The most commonly performed procedure is a colonoscopy, which serves as a colon cancer screening test for those older than 50. You may only need a colonoscopy once every ten years after your first one unless someone in your family has had colon cancer or your doctor discovers multiple polyps. In Colonoscopy Doctors of New York City, gastroenterologists can see inside your body cavities using an endoscopy procedure. A tiny camera at the end of a thin, flexible wire can give your gastroenterology doctor a clear, unobstructed view of potential problems, helping in diagnosis and treatment.