Treatments for colon cancer are usually effective at first but often lose their effectiveness over time because the tumors adapt to them. One way around this hurdle is through combination therapy—using two or more treatments at once those different attack weaknesses of the tumors. Promising therapies for combination therapy include chemotherapy with immune checkpoint inhibitors, radiation treatment with chemotherapy, and taking medications called PARP inhibitors. While these new treatments show strong results in clinical trials, they’re not yet available to the general public. However, some of these treatments have side effects that can make life uncomfortable for patients.
Oncologists use drug combinations to fight cancer tumors.
The best treatment for colon cancer depends on how advanced it is. If you’ve had surgery and your tumor markers are low or average, you may only need chemotherapy if cancer has spread beyond your colon. If your cancer markers are high, radiation therapy with chemotherapy will be more effective at killing any remaining tumors. If the colon cancer has spread to other organs or blood vessels, chemo or immunotherapy is usually necessary. Colon cancer that spreads to other parts of the body is incurable because it’s much harder to remove or kill tumors once they’ve spread.
A man undergoes combined radiation and chemotherapy for colon cancer.
The average five-year survival rate for colorectal cancer is around 65%. If cancer has only reached the innermost lining of your colon, then you have a more than 90% chance of being cured. But if it’s metastasized beyond the colon, it’s no longer curable, even with clinical trials’ latest advances in treatment options. That said, some people may live with advanced colon cancer undetected by standard tests for years after diagnosis because their symptoms are so mild that they don’t notice them.
Your doctor can help determine which treatments are right for you based on your cancer’s grade, location, and metastasis.
Colon cancer is curable with surgery if it hasn’t spread outside the colon or rectum. Unfortunately, removing the entire large intestine means losing some digestive function but usually isn’t a problem for most people because they adapt to their new diet without much trouble. A doctor may also prescribe medications to soothe any symptoms from the removal of your large intestines, such as constipation, diarrhea, nausea, anemia, and fatigue. In some instances, doctors may be able to remove only the tumors instead of removing your entire large intestine—this is called a partial colectomy. Surgeons at high-volume centers have better outcomes than those at low-volume centers after a partial colectomy.
Colon cancer is best treated with surgery if it hasn’t spread beyond the colon.
Suppose your doctor detects any signs of spread to other parts of your body, such as lymph nodes, liver, lungs, or peritoneum (the tissue that lines the abdominal cavity). In that case, they’ll immediately implement chemotherapy and radiation therapy. These treatments are standard for most cases of colon cancer, but there’s one problem: resistance. Tumors can become resistant to these standard chemo and radiation therapies by mutating and evolving. Once a tumor becomes resistant to treatment, doctors can still prescribe experimental drugs with different action methods in clinical trials. This last resort option often halts progressions of tumors temporarily.