This procedure uses a tube-like instrument called a colonoscope to look inside the rectum and colon for polyps, abnormal areas, or cancer. The colonoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove polyps or tissue samples, which are checked under a microscope for signs of cancer.
This procedure is often used as part of a screening test, but can also be used for diagnostic purposes. If you have polyps removed during a screening colonoscopy, they will be evaluated by a pathologist to determine if the cells inside are normal, precancerous or cancerous.
A procedure to look inside the rectum and sigmoid (lower) colon for polyps, abnormal areas, or cancer. A sigmoidoscope is a tool very similar to a colonoscope used for a colonoscopy.
If a mass has been identified during imaging tests and/or a colonoscopy, samples of the tumor cells will be removed so they can be viewed under a microscope by a pathologist to check for signs of cancer. This might be done after a routine colonoscopy where polyps are found and it’s performed after a diagnostic colonoscopy. A biopsy is the only test that can make a definite diagnosis of colorectal cancer.
Some patients have surgery to remove a larger tumor which is then tested for cancer along with nearby lymph nodes to determine if cancer cells have spread outside of the colon.