Colon Polyps and Cancer Make an Appointment Find a Doctor Ask a Question Reviewed by Luette S. Morton, MD (October 01, 2012) The colon is the lower portion of the gastrointestinal tract and is about 5 feet long. A colon polyp is a growth inside the colon. Colon polyps can be small, often less than 1 cm. They can also be larger than 1 cm. These are less common and more likely to develop into colon cancer. Colorectal cancer affects both men and women, most often above 50 years of age. It is one of the most common types of cancer, but colon cancer can be prevented. Screening tests are available that identify and treat the precursors to colon cancer—colon polyps. Types of Colon Polyps There are different types of colon polyps. They include nonneoplastic polyps and neoplastic polyps. Nonneoplastic Polyps: These polyps are not likely to develop into cancer. Hyperplastic polyps, hamartomas, lymphoid and inflammatory polyps are all nonneoplastic polyps. Neoplastic Polyps: These polyps are more likely to develop into cancer. Adenomas are the most common type of neoplastic polyp. Most of the polyps removed during a colonoscopy are adenomas. Once polyps are removed, they are viewed under a microscope. The degree of dysplasia (abnormal cells) is determined. The adenoma may have a low or high degree of dysplasia. Adenomas vary in size. The larger (greater than 1cm) adenomas are more likely to have a high degree of dysplasia. Your doctor will discuss with you the type of polyps that were found during the colonoscopy and recommend further treatment and follow-up. Programs & Services Gastroenterology Program Clinical Trials For more than 100 years, National Jewish Health has been committed to finding new treatments and cures for diseases. Search our clinical trials.