Staging
If the biopsy shows that cancer is present, the doctor needs to know the extent (stage) of the disease to plan the best treatment. The stage is based on whether the tumor has invaded nearby tissues, whether the cancer has spread and, if so, to what parts of the body. Staging may involve some of the following tests and procedures:
- Blood tests: The doctor checks for carcinoembryonic antigen (CEA) and other substances in the blood. Some people who have colorectal cancer or other conditions have a high CEA level.
- Colonoscopy: If colonoscopy was not performed for diagnosis, the doctor examines the entire length of the colon and rectum with a colonoscope to check for other abnormal areas.
- Endorectal ultrasound: An ultrasound probe is inserted into the rectum. The probe sends out sound waves that people cannot hear. The waves bounce off the rectum and nearby tissues, and a computer uses the echoes to create a picture. The picture shows how deep a rectal tumor has grown or whether the cancer has spread to lymph nodes or other nearby tissues.
- Chest x-ray: X-rays of the chest can show whether cancer has spread to the lungs.
- CT scan: An x-ray machine linked to a computer takes a series of detailed pictures of areas inside the body. The patient may receive an injection of dye. Tumors in the liver, lungs, or elsewhere in the body show up on the CT scan.
The doctor also may use other tests (such as MRI) to see whether the cancer has spread. Sometimes staging is not complete until the patient has surgery to remove the tumor. (Surgery for colorectal cancer is described in the "Treatment" section.)
Doctors describe colorectal cancer by the following stages:
- Stage 0: The cancer is found only in the innermost lining of the colon or rectum. Carcinoma in situ is another name for Stage 0 colorectal cancer.
- Stage I: The cancer has grown into the inner wall of the colon or rectum. The tumor has not reached the outer wall of the colon or extended outside the colon. Dukes' A is another name for Stage I colorectal cancer.
- Stage II: The tumor extends more deeply into or through the wall of the colon or rectum. It may have invaded nearby tissue, but cancer cells have not spread to the lymph nodes. Dukes' B is another name for Stage II colorectal cancer.
- Stage III: The cancer has spread to nearby lymph nodes, but not to other parts of the body. Dukes' C is another name for Stage III colorectal cancer.
- Stage IV: The cancer has spread to other parts of the body, such as the liver or lungs. Dukes' D is another name for Stage IV colorectal cancer.
- Recurrent cancer: This is cancer that has been treated and has returned after a period of time when the cancer could not be detected. The disease may return in the colon or rectum, or in another part of the body.
Treatment
Many people with colorectal cancer want to take an active part in making decisions about their medical care. They want to learn all they can about their disease and their treatment choices. However, shock and stress after the diagnosis can make it hard to think of everything they want to ask the doctor. It often helps to make a list of questions before an appointment. To help remember what the doctor says, people may take notes or ask whether they may use a tape recorder. When they talk to the doctor, some people also want to have a family member or friend with them to take part in the discussion, to take notes, or just to listen.
The doctor may refer a person with colorectal cancer to a specialist, or the patient may ask for a referral. Specialists who treat colorectal cancer include gastroenterologists (doctors who specialize in diseases of the digestive system), surgeons, medical oncologists, and radiation oncologists.
