The choice of treatment depends mainly on the location of the tumor in the colon or rectum and the stage of the disease. Treatment for colorectal cancer may involve surgery, chemotherapy, biological therapy or radiation therapy. Some people have a combination of treatments. These treatments are described below.
Colon cancer sometimes is treated differently from rectal cancer. Treatments for colon and rectal cancer are described separately below.
Your doctor can describe your treatment choices and the expected results. You and your doctor can work together to develop a treatment plan that meets your needs.
Cancer treatment is either local therapy or systemic therapy:
Surgery is the most common treatment for colorectal cancer.
When a section of your colon or rectum is removed, the surgeon can usually reconnect the healthy parts. However, sometimes reconnection is not possible. In this case, the surgeon creates a new path for waste to leave your body. The surgeon makes an opening (stoma) in the wall of the abdomen, connects the upper end of the intestine to the stoma, and closes the other end. The operation to create the stoma is called a colostomy. A flat bag fits over the stoma to collect waste, and a special adhesive holds it in place.
For most people, the stoma is temporary. It is needed only until the colon or rectum heals from surgery. After healing takes place, the surgeon reconnects the parts of the intestine and closes the stoma. Some people, especially those with a tumor in the lower rectum, need a permanent stoma.
Chemotherapy uses anticancer drugs to kill cancer cells. The drugs enter the bloodstream and can affect cancer cells all over the body.
Anticancer drugs are usually given through a vein, but some may be given by mouth. You may be treated in an outpatient part of the hospital, at the doctor’s office, or at home. Rarely, a hospital stay may be needed.
Some people with colorectal cancer that has spread receive a monoclonal antibody, a type of biological therapy. The monoclonal antibodies bind to colorectal cancer cells. They interfere with cancer cell growth and the spread of cancer. People receive monoclonal antibodies through a vein at the doctor’s office, hospital, or clinic. Some people receive chemotherapy at the same time.
Radiation therapy (also called radiotherapy) uses high-energy rays to kill cancer cells. It affects cancer cells only in the treated area.
Doctors use different types of radiation therapy to treat cancer. Sometimes people receive two types:
Most patients with colon cancer are treated with surgery. Some people have both surgery and chemotherapy. Some with advanced disease get biological therapy.
A colostomy is seldom needed for people with colon cancer.
Although radiation therapy is rarely used to treat colon cancer, sometimes it is used to relieve pain and other symptoms.
For all stages of rectal cancer, surgery is the most common treatment. Some patients receive surgery, radiation therapy, and chemotherapy. Some with advanced disease get biological therapy.
About 1 out of 8 people with rectal cancer needs a permanent colostomy.
Radiation therapy may be used before and after surgery. Some people have radiation therapy before surgery to shrink the tumor, and some have it after surgery to kill cancer cells that may remain in the area. At some hospitals, patients may have radiation therapy during surgery. People also may have radiation therapy to relieve pain and other problems caused by the cancer.