Rectal Cancer Diagnosis
A colonoscopy is similar to sigmoidoscopy. A colonoscope (a thin, lighted tube) is inserted through the rectum into the colon to look for polyps, abnormal areas, or cancer. Polyps or tissue samples may be taken for biopsy.
A barium enema is a series of x-rays of the colon and rectum. The patient is given an enema containing a barium solution, and air is pumped into the rectum. The barium and air outline the colon and rectum on the x-rays. Polyps may show up on the x-ray. If this test detects polyps or an abnormal area, other tests are needed to help make an accurate diagnosis.
A biopsy is the removal of cells or tissues so they can be viewed under a microscope to check for signs of cancer.