Colon Cancer Diagnosis
To make a diagnosis of colon cancer, your doctor will ask about your symptoms and medical history and may perform a physical exam. One or more tests, such as a barium enema, sigmoidoscopy, or colonoscopy are often necessary when making this type of diagnosis.
If you have any signs or symptoms of colon cancer, your doctor must determine whether they are due to cancer or some other cause. Your doctor will ask about your personal and family medical history, and may do a physical exam.
To make a diagnosis, your doctor may perform one or more tests to look for colon cancer. These are the same tests used for colon cancer screening. They can include:
A rectal exam is often part of a routine physical examination. The doctor or nurse inserts a lubricated, gloved finger into the lower part of the rectum to feel for abnormal areas.
Fecal Occult Blood Test (FOBT)
Sometimes cancers or polyps bleed, and the FOBT can detect tiny amounts of blood in the stool. If this test detects blood, other tests (such as a colonoscopy) are needed to find the source of the blood. Other conditions, like hemorrhoids, can also cause blood in the stool.
During a sigmoidoscopy, the doctor checks inside the rectum and lower (sigmoid) colon with a lighted tube called a sigmoidoscope. If polyps or other unusual areas are found, the doctor may remove them or take a tissue sample (biopsy) to check for cancer cells.