Treatment for Recurrent Colorectal Cancer

If your cancer has returned to your colon or rectum, your tumor might be removed surgically by resection. Your doctor might give you chemotherapy before you have surgery to shrink the tumor. Another option is intraoperative radiotherapy (IORT), in which a tube containing radiation is placed near the tumor before the surgery to shrink the cancer. If you don’t have IORT, you might have some external radiation therapy after your surgery.

• Resection - Your doctor will remove the cancer and a small amount of the healthy tissue surrounding the cancer. The doctor will usually sew the healthy parts of the colon together so that your bowel can continue to function normally. This procedure is known as anastomosis. In anastomosis, the doctor often removes lymph nodes near the colon and examines them under a microscope to find out if they have any cancer cells.

If the tumor is large and has created a hole in your colon, you might need a temporary colostomy. In a colostomy, an opening is made in the abdomen and one end of the large intestine is attached to this opening. Stool comes through the intestine, out the opening, and into a replaceable plastic bag. You will wear this bag outside your body. Often, you will only need the colostomy for a short time. As soon as your colon heals, the doctor can sew the two ends of the colon back together. In very rare cases, when the cancer cannot be completely removed, the two ends of the colon are not sewn back together and the colostomy becomes permanent.

About half of all patients with colorectal cancer have liver metastases, or cancer cells that have spread from the colon or rectum to the liver. Metastases in the liver and other organs are sometimes removed surgically by resection. If resection is not possible, the surgeon might use one of these techniques:

• Radiofrequency ablation - In some cases, the physician uses a special probe with tiny electrodes that kill cancer cells. This probe is sometimes inserted directly through the skin. In other cases, the doctor cuts into the abdomen to insert the probe.
• Cryosurgery - In cryosurgery, the surgeon uses an instrument to freeze and destroy the tumor. This is especially useful for metastases in the liver.
  If you have rectal cancer, you might be treated with radiation therapy and chemotherapy before surgery. This reduces the chance that the cancer will come back and can make the surgery more effective.

Many patients with recurrent colorectal cancer are treated with chemotherapy after their surgery, typically with one or more of the drugs listed below, either alone or in combination. You are likely to be treated with chemotherapy if your metastases cannot be removed with surgery. If you have already had chemotherapy, your doctor will prescribe drugs that you haven’t tried yet.

• Camptosar^® (irinotecan) - Irinotecan can be used in combination with other chemotherapy drugs, especially fluorouracil (5-FU) and leucovorin, as the first treatment for metastatic colorectal cancer (cancer that has spread to other parts of the body). This combination is known as FOLFIRI for folinic acid, 5-FU, and irinotecan.
  Some people have an inherited genetic variation that makes it hard for them to tolerate irinotecan. Luckily, a test is available to find out if you have this genetic variation. If you do, your doctor will prescribe a different chemotherapy drug or drugs for you.
• Eloxatin^® (oxaliplatin) - This drug can be very effective when it is combined with 5-FU and leucovorin. Sometimes, oxaliplatin is combined with both 5-FU and folinic acid. This combination is known as FOLFOX for folinic acid, 5-FU, and oxaliplatin. FOLFOX seems to be the most effective treatment for colorectal cancer that has returned (recurred) after it was originally treated.
• Fluorouracil (5-FU) - This is the drug used most often to treat colorectal cancer. 5-FU is often given with another drug, leucovorin, to make it more effective. Patients usually receive injections of 5-FU over a few days or weeks and then take a few weeks off from chemotherapy. These cycles are repeated over 6 months to a year.
• Xeloda^® (capecitabine) - Capecitabine is usually taken by mouth. It actually turns into 5-FU when it gets to the tumor. This drug can be used instead of 5-FU, and it acts as if the 5-FU were being given continuously.
  If you have liver metastases, you might receive chemotherapy directly into the artery that goes to the liver. This shrinks cancers in the liver more effectively than giving the chemotherapy intravenously (through a vein).
  Patients with recurrent colorectal cancer are sometimes treated with targeted treatments. These are new therapies that affect cancer cells but do little damage to noncancer cells. These drugs are becoming more important in the treatment of colorectal cancer. These treatments are sometimes known as immunotherapies because they help the patient’s immune system fight cancer more effectively.
• Antiangiogenesis therapy - Tumors need the nutrients in blood vessels to grow and spread. Antiangiogenesis therapies stop the process of making new blood vessels, known as angiogenesis, by “starving” the tumor. Avastin^® (bevacizumab) is one of these therapies and it works by blocking the growth factors that stimulate the development of new blood vessels. Bevacuzimab is given with chemotherapy to improve survival in people with advanced colorectal cancer.
• Epidermal growth factor receptor (EGFR) inhibitors - The EGFR protein seems to help many colorectal cancers grow. Erbitux^® (cetuximab) is a monoclonal antibody, or protein used by the immune system, that can find and attach itself to cancer cells and can block the EGFR protein. Cetuximab can sometimes shrink tumors in patients whose cancers continue to grow after other treatments. Cetuximab can be used with or without irinotecan. VectibixTM (panitumumab), another monoclonal antibody, is a newer EGFR inhibitor that can shrink tumors in some people whose cancer has not responded to other treatments. Vectibix is used to treat certain colorectal cancers that have metastasized (spread to other parts of the body) and continue to grow after treatment with combinations of chemotherapy drugs that include 5-FU, oxaliplatin, or irinotecan.
  

Radiation therapy is another treatment that is used for people with recurrent colorectal cancer. It can help reduce certain symptoms, such as pain.

• External beam radiation therapy (EBRT) - This is the most common type of radiation treatment for people with colorectal cancer. A machine called a linear accelerator directs the radiation at the tumor from outside your body. The treatments last just a few minutes and are given 5 days a week for several weeks.