Overview of Colon Cancer Treatment Options

There are different types of treatments for patients with colon cancer.

There are different types of treatments for patients with colon cancer. Some treatments are standard of care (the currently used treatment) and some are being tested in clinical trials. Treatment option clinical trials are studies to get information for improving current treatment options or for new treatment options for people with cancer. When a clinical trial shows that a new treatment option is better than the standard treatment option, the new treatment option has the potential to become the standard treatment option. Patients may want to consider participating in a clinical trial. Some clinical trials are only open to patients who have not started treatment.

There are 7 standard treatment options used:

Surgery

Surgery (removing the tumor surgically) is the most common treatment option for all stages of colon cancer. Doctors may remove the tumor with one of the following procedures:

Local excision: If the cancer is found early, doctors may be able to remove it without cutting through the abdominal wall. Instead, the doctor may place a tube with a shearing tool through the rectum into the colon and remove the tumor. This is called a local excision. If the tumor is found in a polyp (a small raised area of tissue), the procedure is called a polypectomy.

Colonic resection anastomosis: If the tumor is larger, the doctor may use a partial resection of the colon (removing the tumor and a small amount of healthy tissue around it). The doctor may then perform an anastomosis (suturing the healthy part of the colon together). Doctors also usually remove the lymph nodes near the colon and examine them under a microscope to determine if the lymph nodes contain cancer cells. Three-panel drawing showing colon cancer surgery with anastomosis; first panel shows the area of the colon with cancer, middle panel shows the cancer and nearby tissue removed, last panel shows the cut ends of the colon joined.

Three-panel drawing showing colon cancer surgery with anastomosis; first panel shows the area of the colon with cancer, middle panel shows the cancer and nearby tissue removed, last panel shows the cut ends of the colon joined.

Colonic resection anastomosis. Part of the colon with the tumor and nearby healthy tissue is removed, and the cut edges of the colon are then sutured together.

Colonic resection stoma: If the doctor cannot sew the two ends of the colon together, a stoma (opening) is made outside the body to pass stool. This procedure is called a colostomy. A bag is placed around the stoma to collect the waste. Sometimes a colostomy is only needed until the lower colon has healed and then it can be reversed. Three-panel drawing showing colon cancer surgery with colostomy; first panel shows the area of the colon with cancer, middle panel shows the cancer and nearby tissue removed and a stoma created, last panel shows a colostomy bag attached to the stoma.

Three-panel drawing showing colon cancer surgery with colostomy; first panel shows the area of the colon with cancer, middle panel shows the cancer and nearby tissue removed and a stoma created, last panel shows a colostomy bag attached to the stoma.

Colorectal cancer colostomy. Part of the colon with cancer cells and nearby healthy tissue is removed to create a stoma, and then a colostomy bag is attached to the stoma.

After the surgeon removes all of the tumor that can be seen at the time of surgery, some patients may receive chemotherapy or radiation therapy after surgery to kill any remaining cancer cells. The treatment given after surgery to reduce the risk of the cancer coming back is called adjuvant therapy.

Radiofrequency ablation

Radiofrequency ablation uses special probes with small electrodes that can kill cancer cells. Sometimes the probe is inserted directly into the skin and requires only local anesthesia. In other cases, the probe is inserted through an incision in the abdomen. This is done in a hospital through general anesthesia.

Cryosurgery

Cryosurgery is a treatment that uses an instrument to freeze and destroy abnormal tissue. This treatment is also known as cryotherapy.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to inhibit the growth of cancer cells. The drugs can kill the cells or stop them from dividing. When chemotherapy is given by mouth or by intravenous or intramuscular injection, the drugs enter the bloodstream and reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy drugs are placed directly in the cerebrospinal fluid, organs, or body cavities (such as the abdomen), the drugs affect cancer cells primarily in those areas (local chemotherapy).

Hepatic artery embolization chemotherapy may be used to treat cancers that have spread to the liver. This involves blocking the hepatic artery (the main artery that supplies blood to the liver) and injecting an anti-cancer drug between the blockage and the liver. The arteries of the liver then deliver the drug to the entire liver. Only a small amount of the drug reaches other parts of the body. The blockage may be temporary or permanent, depending on what is used to block the artery. The liver will continue to receive some blood from the portal vein of the liver, which carries blood from the stomach and intestines.

The approach used for chemotherapy depends on the type and stage of cancer to be treated.

For more information, see Drugs approved for colon and rectal cancer.

Radiotherapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or stop them from growing. There are two types of radiation therapy:

Ex vivo radiation therapy uses a machine outside the body to send radiation to the tumor site.

In vivo radiation therapy involves sealing radioactive material in a needle, radioactive particle, guide wire, or catheter and placing it directly on or near the tumor.

The type of radiation therapy used depends on the type and stage of the cancer. External radiation therapy is used as palliative care to relieve symptoms and improve quality of life.

Targeted therapy

Targeted therapy is a treatment that uses drugs or other substances to identify and attack specific cancer cells while not harming normal cells.

Targeted therapies used to treat colon cancer include the following:

Monoclonal antibodies: Monoclonal antibodies are made in the laboratory from a single type of immune system cell. These antibodies recognize substances on cancer cells or normal substances that might help cancer cells grow. The antibodies attach to these substances and kill the cancer cells, inhibit the growth of the cancer cells, or stop the spread of the cancer cells. Monoclonal antibodies are given by infusion. They can be used alone, or they can carry drugs, toxins, or radioactive substances directly to cancer cells.

There are different types of monoclonal antibody therapy:

Vascular endothelial growth factor (VEGF) inhibitor therapy:Cancer cells produce a substance called VEGF, which causes the formation of new blood vessels (angiogenesis) and promotes cancer cell growth.VEGF inhibitors block VEGF and inhibit the formation of new blood vessels. This may kill cancer cells because they need new blood vessels to grow. Bevacizumab and ramolutumab are VEGF inhibitors and angiogenesis inhibitors.

Epidermal growth factor receptor (EGFR) inhibitor therapy: EGFR is a protein found on the surface of certain cells, including cancer cells. Epidermal growth factor attaches to the epidermal growth factor receptor on the cell surface, causing the cells to grow and divide. EGFR inhibitors block the receptor, preventing epidermal growth factor from attaching to cancer cells. This inhibits the growth and division of cancer cells. Cetuximab and panitumumab are EGFR inhibitors.

Angiogenesis inhibitors: Angiogenesis inhibitors inhibit the growth of new blood vessels that are needed for tumor growth.

Abciximab is a vascular endothelial growth factor capture factor that blocks an enzyme needed for neovascular growth in tumors.

Regorafenib is used to treat colorectal cancer that has spread to other parts of the body and has not improved with other treatments. Blocks the action of certain proteins, including vascular endothelial growth factor. This may help stop cancer cells from growing and may kill them. It may also inhibit the growth of new blood vessels needed by the tumor.

See Approved drugs for colon and rectal cancer for more information.

Immunotherapy

Immunotherapy is a treatment that uses the patient’s immune system to fight cancer. Substances produced in the body or produced in the laboratory are used to enhance, direct, or restore the body’s natural defenses against cancer. This type of cancer treatment is also known as biologic therapy or biologic treatment.

Immune checkpoint inhibitor therapy is a form of immunotherapy:

Immune checkpoint inhibitor therapy: PD-1 is a protein on the surface of T cells that helps control the body’s immune response. When PD-1 attaches to another protein called PDL-1 on cancer cells, it prevents T cells from killing cancer cells. PD-1 inhibitors attach to PDL-1, enabling T cells to kill cancer cells. Pabrolizumab is an immune checkpoint inhibitor. Immune checkpoint inhibitor; the panel on the left shows the binding of proteins PD-L1 (on the tumor cell) to PD-1 (on the T cell), which keeps T Also shown are a tumor cell antigen and T cell receptor. The panel on the right shows immune checkpoint inhibitors (anti-PD-L1 and anti-PD-1) blocking the binding of PD-L1 to PD-1, which allows the T cells to kill tumor cells.

Immune checkpoint inhibitor; the panel on the left shows the binding of proteins PD-L1 (on the tumor cell) to PD-1 (on the T cell), which keeps T Also shown are a tumor cell antigen and T cell receptor. The panel on the right shows immune checkpoint inhibitors (anti-PD-L1 and anti-PD-1) blocking the binding of PD-L1 to PD-1, which allows the T cells to kill tumor cells.

Immune checkpoint inhibitors. Checkpoint proteins, such as PD-L1 on tumor cells and PD-1 on T cells, help control the immune response. the binding of PD-L1 to PD-1 prevents T cells from killing tumor cells in the body (left). Blocking the binding of PD-L1 to PD-1 with an immune checkpoint inhibitor (anti-PD-L1 or anti-PD-1) allows T cells to kill tumor cells (right).

Immunotherapy uses the body’s immune system to fight cancer. This animation explains an immunotherapy that uses immune checkpoint inhibitors to treat cancer.

For more information, see Approved drugs for colon and rectal cancer.

New treatment options are being tested in clinical trials.

Information on clinical trials is available on the NCI website.

Treatment for colon cancer may have side effects.

For information on side effects of cancer treatment, see our side effects page.

Patients may want to consider participating in a clinical trial.

For some patients, participating in a clinical trial may be the best treatment option. Clinical trials are part of the cancer research process. Clinical trials are used to see if a new cancer treatment is safe and effective or better than standard treatment.

Today, many standard treatments for cancer are based on early clinical trials. Patients who participate in clinical trials may receive the standard treatment option or be called one of the first to receive the new treatment.

Patients who participate in clinical trials can also help improve treatments for future cancers. Even if clinical trials do not result in effective treatments, they often answer important questions and help advance research.

Patients can participate in clinical trials before, during, or after they start cancer treatment.

Some clinical trials include only patients who have not received treatment. Other trials test treatment options for patients whose cancer has not progressed. There are also clinical trials testing new ways to prevent the cancer from coming back (returning) or to reduce the side effects of cancer treatment.

Clinical trials are being conducted in many parts of the country. Information about NCI-supported clinical trials can be found on the NCI’s Clinical Trials Search page. Clinical trials supported by other organizations can be found on the ClinicalTrials.gov website.

Follow-up tests may be needed.

Some trials used to diagnose cancer or find cancer staging may have to be repeated. Some tests used to find out the effect of a treatment regimen are repeated. Decisions about whether to continue, change, or stop treatment are likely to be based on the results of these trials.

Some tests should continue from time to time after treatment ends. The results of these tests can show whether your condition has changed or whether the cancer has come back. These tests are sometimes called follow-up tests or exams.