There are four major treatments for colorectal cancer. They are surgery, chemotherapy, radiation therapy, and targeted therapy. Different combinations of these treatments may be used, depending on the stage (extent) of the cancer and other factors. Other kinds of treatment are being studied in clinical trials. One such therapy is immunotherapy. Each treatment has its own goals. Here is an overview of each type of treatment:
Surgery. This is the most common treatment for most early stages of colon and rectal cancer. The goal of this treatment is to remove the entire tumor and any cancer cells that may have spread to nearby tissue. Depending on the stage of the cancer, surgery may be all that's needed. Or surgery may come before or after another treatment is used.
Chemotherapy. The goal of chemotherapy is to stop cancer from growing or spreading. It does this by using drugs to either kill the cells or stop them from dividing. If the drugs are given in a way that lets them enter the bloodstream, they treat cancer cells throughout the body. That way they can treat cancer that has spread. This type of treatment is said to be systemic. Drugs can also be administered to attack cancer cells in specific organs, such as the liver. This treatment is said to be local. Chemotherapy might also be used before surgery to shrink tumors. When used before surgery, it is called neoadjuvant therapy. It might be used after surgery to kill or control any remaining cancer cells. When used after surgery, it is called an adjuvant therapy.
Radiation therapy. The goal of radiation therapy is to kill cancer cells and prevent recurrence. To do this, it uses high-energy X-rays to kill the cancer cells. It has a major role in treating rectal cancers, but it may be used in some colon cancers as well. Like chemotherapy, it may be used before surgery to shrink tumors. This treatment is called neoadjuvant radiation therapy. This may lower the chance that a person will need a permanent colostomy. When it's used after surgery, it is called adjuvant radiation therapy. Then the goal is to reduce the chance that the cancer will come back.
Targeted therapy. This type of therapy uses drugs that target proteins or cell functions that help cancer grow. Some of these drugs are given along with chemotherapy drugs, while others are used by themselves. The goal is to prevent the cancer from growing. It may also be used to help chemotherapy get inside the tumor. This allows it to be more effective.
Researchers are still studying other biologic or immunologic techniques that could help the body's immune system fight the cancer. Because clinical trials study new treatments, you should talk with your health care provider to see if there are any you should consider.