Options for colorectal cancer treatment depend mainly on the location of the tumor in the colon or rectum and the stage of the disease. Treating colon or rectal cancer may involve surgery, chemotherapy, biological therapy, or radiation therapy. Some people have a combination of treatments. Your colorectal cancer doctor can describe your treatment choices and the expected results. Colon cancer sometimes is treated differently from rectal cancer.
Your medical oncologist, the specialized doctor who leads your cancer care treatment team, will explain the different treatments that may be a part of your personalized plan and the expected results. Colon and rectal cancer treatments are either local therapy or systemic therapy:
Treatments for colon and rectal cancer are described separately below.
Patients with early-stage colon cancer are likely to have surgery to remove the tumor. For those who also need systemic treatment, a chemotherapy called FOLFOX is commonly used. Advanced colon cancers, or those that have recurred, can also be treated using targeted therapies that focus on a specific genetic mutation found in the patient's bloodwork, called a biomarker. These biomarkers let oncologists know which targeted therapy is most likely to work.
Radiation therapy isn't used for all patients with colon cancer. Still, it can be a useful tool to help shrink a tumor before surgery, kill any remaining cancer cells after surgery, or help relieve pain that a tumor may be causing in the colon or in other areas of the body.
For all stages of rectal cancer, surgery is the most common treatment method. Some patients may receive surgery, radiation therapy, and chemotherapy as part of their treatment plan for rectal cancer. Some with advanced diseases receive targeted therapy.
About 1 out of 8 people with rectal cancer need a permanent colostomy.
Radiation therapy may be used before and after surgery. Some patients may have radiation therapy before surgery to shrink the tumor, and some may have it after surgery to kill cancer cells that may remain in the area. People also may have radiation therapy to relieve pain and other problems caused by the cancer.
Surgery is the most common treatment for colorectal cancer.
How close the tumor is to the anus impacts the type of surgery performed. Common procedures for rectal cancer treatment can include:
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.
The chemo regimen commonly recommended to kill colorectal cancer cells in the colon, rectum, and throughout the body is called Folfox. This well-established treatment has proven very effective for many colorectal cancer patients. Based on your stage of colorectal cancer, it can be used before surgery to shrink tumors before operating or after surgery to help kill any cancer cells that may remain in the body through the lymph system.
Radiation therapy (also called radiotherapy) uses high-energy rays to kill cancer cells. It affects cancer cells only in the treated area and is often used for colorectal cancer patients because the cancer tends to recur in the same place it was previously found. It may be given before surgery, after surgery, or both depending on whether the cancer spread and what was found during surgery.
Your cancer care team will include a radiation oncologist who specializes in determining the right type and amount of radiation therapy that may be needed. This is based on the stage of cancer and its location in the body.
Different types of radiation therapy used to treat colon and rectal cancer:
Immunotherapy, also known as biological therapy, uses the body's immune system to fight cancer. This type of cancer treatment uses materials made by the body or in a laboratory to simulate a natural substance.
A relatively new cancer treatment, immune checkpoint inhibitors, is a drug that blocks proteins called checkpoints that are made by some types of immune system cells, such as T cells and some cancer cells. The checkpoints keep the immune system from responding properly and sometimes can keep T cells from killing cancer cells. Using the inhibitor blocks the proteins to reinforce the body’s ability to fight the cancer cells.
Some people with colorectal cancer that has spread receive a monoclonal antibody that binds to colorectal cancer cells. They interrupt cancer cell growth and the spread of cancer. Patients receive monoclonal antibodies through a vein at the doctor’s office, hospital, or clinic. Some people receive chemotherapy at the same time.
Targeted therapy drugs aim at specific genes, proteins, or tissues that are contributing to the cancer’s growth and blocks them while allowing healthy cells to grow with little impact. For colon cancer patients who are advanced stage or have recurring cancer, targeted therapies may be an option.
Biomarker testing is done to see if there is a genetic mutation that can be targeted with a specific drug. These are not inherited gene mutations, but rather mutations that have been caused by other factors over time based on exposure to the environment and various foods.
Avastin is an FDA-approved targeted therapy used to treat colorectal cancer that has returned. This may be the best therapy to use next unless the biomarker testing results show signs of a genetic mutation that can be treated by a different targeted therapy.
Recently, many new colorectal cancer treatments have been approved and used in combination with long-standing treatments. New treatments for some types of colorectal cancer replace the first line of treatment previously given. Compass Oncology has been participating over the years in these studies and currently offers clinical trials to patients with colon cancer or rectal cancer.
A clinical trial is a carefully monitored research study meant to help introduce new treatment or improve upon current treatment options. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment, which is what we are seeing with lung cancer in the past 5 years.
Your oncologist will discuss possible clinical trial participation if you meet a study's criteria for participation.
Learn more about the cancer clinical trials available at Compass Oncology.
If you have been newly diagnosed with colorectal cancer, the next step is to schedule a consultation with an oncologist. If you are in the Portland, OR, or Vancouver, WA area, we offer personalized treatment plans and second opinions on treatment. You can find a location near you to talk with an oncologist about your specific diagnosis and treatment plans.