Being diagnosed with colorectal cancer, a type of cancer that starts in the colon or rectum, can be devastating—and startling—news. These types of cancers don’t usually cause obvious symptoms, like blood in the stool or abdominal pain, until they’re advanced. The good news is that if caught early enough, the five-year survival rate is as high as 90 percent. This is due in part to advancements in colon cancer treatment, as well as preventative screenings. More cancers are caught at an early stage thanks to colonoscopy, flexible sigmoidoscopy and other tests.
What is colon cancer staging?
Once you’re diagnosed with colon cancer, you’ll meet with an oncologist to determine how much the cancer has spread. This is called staging. The stages range from 0 to 4, with 0 being the least severe and 4 being the most serious.
- Stage 0: Cancer cells are only found in the inner layer of the colon
- Stage 1: Cancer cells have spread to the middle layers of the colon
- Stage 2: Cancer cells have spread into or through the colon wall
- Stage 3: Cancer cells have spread to the lymph nodes
- Stage 4: Cancer cells have spread through the lymph nodes to other organs, such as the lung or liver
Determining your stage
To make an accurate assessment, your doctor will take biopsies and perform one or more imaging tests, such as CT, MRI, x-rays or PET scan. Based on the results of these tests, your doctor may operate to remove the tumor and get a more accurate look at how far it has spread.
Understanding treatment options
While treatment choices depends on each individual’s case, the range of options is typically based on the stage and location of the cancer. These include the following.
- Stage 0: Surgery to remove the cancerous polyp (polypectomy) or surgery to remove cancer cells and nearby tissue (local excision through a colonoscope)
- Stage 1: Surgery to remove a cancerous polyp or for cancers not in a polyp; surgery to remove a section of the colon and nearby lymph nodes (partial colectomy)
- Stage 2: Surgery to remove the section of the colon with cancer and nearby lymph nodes; chemotherapy following surgery, if your doctor feels there’s a high risk of recurrence
- Stage 3: Surgery to remove the section of the colon with cancer and nearby lymph nodes, followed by chemotherapy and/or radiation
- Stage 4: Surgery to remove the section of the colon with cancer, nearby lymph nodes and other areas where the cancer has spread (metastases). If it’s determined that the cancer has spread too far, surgery won’t, in most cases, provide a cure. If surgery is possible, chemotherapy would likely be given before and after the operation.
Some people with advanced colorectal cancer may also be candidates for immunotherapy, during which medication is used to help a patient’s immune system destroy cancer cells. There are multiple FDA-approved drugs available for this purpose, including pembrolizumab (Keytruda) and bevacizumab (Avastin), with many more in development.
What to expect after treatment
If you have surgery to treat colon cancer—even minor surgery—you’ll likely experience some pain (which can be managed with medication) and eating problems for a few days. Depending of your form of treatment, side effects may include rectal bleeding or blood clots in your legs. You’ll likely feel especially tired. In rare instances, the external incision may open up and become an open wound, or the anastomosis in the colon may leak, leading to an infection.
Some people may also need a temporary or permanent colostomy, where the colon is brought through an incision in the abdomen and a pouch is attached to collect waste. Colostomy is typically needed if so much of the colon is removed that the remaining bowel can’t function properly. A colostomy may be temporary if bowel function returns after the colon has healed.
Radiation for colon cancer can cause skin irritation, nausea, bowel incontinence and fatigue. Radiation may also cause impotence in men and irritation of the vagina for women.
Chemotherapy for colon cancer can cause hair loss, mouth sores, nausea, vomiting, fatigue and increase your chances of infection.
Your doctor will discuss with you the possible side effects before a treatment plan is put into place.
Life after colon cancer
There are now more than 1 million colorectal cancer survivors in the U.S.—and you can be one of them. For some people, no further treatment is required once the cancer is removed, especially if it’s removed in the early stages. For others, the cancer may never go away completely; for those patients, chemotherapy and radiation are required to control growth and keep the cancer from spreading.
Your doctor will want to keep a close eye on your health, requiring follow-up exams every three to six months. These exams may extend to two years after treatment, depending on the stage at which you were first diagnosed.
Regardless of where you fall in the spectrum after treatment, taking steps such as eating a nutritious diet, keeping stress levels under control and exercising can drastically improve your chances of staying healthy.
Medically reviewed in August 2019.
American Cancer Society: “Survival Rates for Colorectal Cancer,” “Colorectal Cancer,” “Key Statistics for Colorectal Cancer,” “Colorectal Cancer Stages,” “Treatment of Colon Cancer, by Stage,” “Surgery for Colon Cancer,” “Immunotherapy for Colorectal Cancer.”
Cancer Research Institute: “Immunotherapy for Colorectal Cancer.”
Drugs.com: “Medications for Colorectal Cancer.”
National Cancer Institute: “Treatment Clinical Trials for Colon Cancer.”