A colonoscopy allows the doctor to perform a visual examination of the inside of the entire colon. The doctor may take biopsies from the lining of the colon and send them to pathology to determine what is causing symptoms.
During a colon cancer screening, your gastroenterologist is looking for polyps, which can look like a tiny, flat growth on the lining of the colon or they could be larger and have additional growths on them, looking like a tiny tree or mushroom. Any polyp is suspicious, but most polyps do not necessarily lead to a colon cancer diagnosis.
- Hyperplastic polyps are non-precancerous growths.
- Adenomatous polyps are usually not cancerous, but they do have the potential to become cancerous, so patients with this type of polyp will be followed more closely than someone with a completely normal, polyp-free colonoscopy.
- Villous adenomas are larger and have more dimension. They are more likely to become cancerous than an adenomatous polyp.
If polyps are found during a colonoscopy, the doctor will remove them and send them to pathology for testing to determine whether they are benign, precancerous or cancerous. The lab tests provide accurate information for the doctor whether they are diagnosing colon cancer, determining an increased possibility of cancer or determining there is no present risk to the patient.