Cancer that begins in the colon is called colon cancer, and cancer that begins in the rectum is called rectal cancer. Cancers affecting either of these organs may also be called colorectal cancer.
The colon and rectum are both parts of the body's digestive system, which removes nutrients from food and stores waste until it passes out of the body. Together, the colon and rectum form a long, muscular tube called the large intestine (also called the large bowel). The colon is the first 6 feet of the large intestine and the rectum is the last 8 to 10 inches.
Once cancer has been diagnosed, the next step is to determine the stage of disease. During staging, the doctor will be able to find out whether the cancer has spread, and, if so, where it has spread. Colon cancer can be classified into one of several stages:
Cancer in this stage has been detected very early; at this point it is only in the innermost lining of the colon or rectum.
Stage I cancer is situated on more of the inner wall of the colon or rectum.
Stage II cancer has spread outside the colon or rectum to nearby tissue, but not to the lymph nodes. (Lymph nodes are small, bean-shaped structures that are part of the body's immune system)
At this stage, cancer has spread to nearby lymph nodes, but not to other parts of the body.
The cancer has spread to other parts of the body. Colorectal cancer tends to spread to the liver and/or lungs.
Treatment of colorectal cancer depends mostly on the size, location, and stage of the tumor, as well as on the patient's general health. The most common treatment for colorectal is surgery; usually, the surgeon removes the tumor and part of the healthy colon or rectum and nearby tissues in a procedure known as a colectomy. Generally, the doctor is also able to reconnect the remaining healthy parts of the colon or rectum; if not, a temporary of permanent colostomy is necessary to provide a new path for waste material to exit the body. About 15% of colorectal cancer patients will need a permanent colostomy.
Patients with colorectal cancer may also receive chemotherapy, radiation therapy, or biotherapy. Chemotherapy is often given to destroy any cancerous cells that surgery could not remove, to control tumor growth, or to relieve symptoms of the disease. Because chemotherapy is a systemic treatment, it affects the entire body and may be particularly useful if the cancer has metastasized, or spread, to other parts of the body.
Radiation therapy, also called radiotherapy, involves the use of high-energy x-rays to kill cancer cells. Radiation therapy is a local therapy, meaning that it affects the cancer cells only in the treated area. Most often it is used in patients whose cancer is in the rectum. Biological therapy, also called immunotherapy, uses the body's immune system to fight cancer. The immune system finds cancer cells in the body and works to destroy them.
Many patients and their families want to learn all they can about colorectal cancer and the treatment choices so they can take an active part in decisions about medical care. The doctor is the best person to answer these questions. When discussing treatment, the patient may want to talk with the doctor about research studies of new treatment methods. Such studies, called clinical trials, are designed to improve cancer treatment. More information about clinical trials is in the Clinical Trials section.
Researchers are finding better ways to treat colorectal, and the chances of recovery keep improving. Still, it is natural for patients and their families to be concerned about the future. There are many resources available both on and off the web for patients and their families. Links to some good websites can be found on our web resources page, or check out our recommended reading list for patients and their families.Source: NCI Cancernet