Colon cancer: when is surgery needed and when is chemotherapy needed?

You can listen to this article below, or by using your favourite podcast player at pod.link/oncologybuddies

When treating colon cancer, there are two options available: chemotherapy and surgery. Radiotherapy can be used in a few very exceptional cases, but these are rare and need to be considered carefully as the colon is very close to other organs that can be damaged by the radiation.

Surgery for colon cancer

Surgery can be used to cure colon cancer if the cancer is at an early stage. Your surgeon can remove the cancer with the lymph nodes around it. This is then sent to a laboratory to check whether the cancer has spread to the nodes. If the nodes are clear and the cancer shows no signs of being high risk for having spread already, then there is an excellent chance that the surgery will cure the cancer.

If the cancer has spread to the lymph nodes or shows features of being high risk for spread, then chemotherapy may be added after the surgery. This is called adjuvant chemotherapy.

If you need chemotherapy after your surgery, it’s not because you still have cancer left inside; it’s to reduce the risk of the cancer coming back.

Surgery also has a role in helping to manage the complications of cancer even if the cancer is no longer curable. Colon cancer can sometimes block the bowel and surgery may be required to remove or bypass the blockage.

Chemotherapy for colon cancer

Chemotherapy is most often offered after surgery if the cancer can be cured. Sometimes, if the cancer is very big or has grown into organs that are nearby, then chemotherapy may be used before the surgery to make it smaller so that the surgery will be successful. This is called neo-adjuvant chemotherapy.

Recent research has shown that routine chemotherapy given before surgery for operable cancer can make the surgery easier but doesn’t make the eventual outcome any better.

Immunotherapy for colon cancer

There is a genetic group of colon cancer types that respond very well to immunotherapy that helps the body’s immune system to recognise the cancer cells and remove them.

For these patients, immunotherapy alone may offer a cure for their cancer. There is a possibility that up to 20% of patients with colon cancer may be helped by this drug. There can be severe side effects, but the potential benefit may be high. Most laboratories now test for this genetic subtype routinely.

Combination of surgery and chemotherapy

As you can see, a combination of surgery and chemotherapy are most commonly required to treat colon cancer. Both the surgery and chemotherapy will be tailored to the specific type of cancer to achieve the best result.