What Are Colorectal Cancer Treatments by Stage?

Medically Reviewed by Michael W. Smith, MD on September 17, 2020

The treatment you get for colorectal cancer may depend on the “stage” of the disease. For all except stage IV, you will first get surgery to remove the tumor. You may also get other treatments.

Stage 0 Colorectal Cancer Treatment

Stage 0 colorectal cancer is only in the innermost lining of the colon or rectum. Surgery should be able to take it out.

Your procedure will depend on how big the cancer is. Your surgeon could remove the tumor and a little tissue near it. They may call this procedure a polypectomy.

If you have larger tumors, your surgeon may need to take out the diseased part of the colon and reattach the healthy tissue so that your bowels still work. This is called an anastomosis.

Your doctor may also consider radiation treatment, either externally (beamed in from the outside) or internally (radioactive beads that go inside your body).

Stage I Colorectal Cancer Treatment

Stage I tumors have spread beyond the inner lining of the colon or rectum to the second and third layers and the inside wall. The cancer hasn’t spread to the outer wall of the bowel or outside it.

At this stage, most people will have surgery to remove the cancer and a small amount of tissue around it. You probably won’t need additional treatments.

If the tumor is small or you are very old or sick, your doctor could use only radiation. They may also add chemotherapy to give the treatment a boost.

Stage II Colorectal Cancer Treatment

Stage II colorectal cancers are larger and go through the muscular wall of the bowel. They may have spread to places nearby like the bladder, uterus, or prostate gland. But there is no cancer in distant organs or lymph nodes, small structures that make and store cells that fight infection, and that filter out harmful things.

You’ll probably have surgery to remove the cancer and an area around it, as well as any places where it’s spread. You may get radiation and chemotherapy before or after surgery.

Stage III Colorectal Cancer Treatment

Stage III colorectal cancers have spread to one or more lymph nodes.

Your doctor may talk about stage lIl A, B, or C tumors. Here’s what that means:

Stage lIlA. Tumors are within the colon or rectum wall and involve the lymph nodes.

Stage lIlB. Tumors have grown through the wall and have spread to one to four lymph nodes.

Stage lIlC. Tumors have spread to more than four lymph nodes.

Treatment involves:

  • Surgery to remove the tumor and all involved lymph nodes, if possible
  • Chemotherapy after surgery
  • Radiation if the tumor is large and has spread to nearby tissue

Stage IV Colorectal Cancer Treatment

Stage IV colorectal cancers have spread to far-off parts of the body, often the liver or lungs. Your doctor may say the cancer has “metastasized” or call it "metastatic” cancer.

The tumor can be any size and may or may not include your lymph nodes.

Treatment may include:

Chemotherapy. This is the main treatment at this stage. You may also get medications including:

Targeted therapy. Your doctor may consider regorafenib (Stivarga) if your colorectal cancer has spread despite other treatment.

Surgery. You could need an operation to remove the cancer in the colon and in places where it has spread. Or you may have surgery to bypass the cancer and connect the healthy parts of your colon. Surgery can often relieve or avoid blockage of the rectum or treat bleeding that is otherwise hard to control. It’s not generally considered a cure, though it may help you live longer. If you have one or two liver tumors, your surgeon may be able to remove them. Other options include freezing the tumors (cryosurgery) or destroying them with microwaves or heat (radiofrequency ablation).

Radiation to ease symptoms.

You may also want to talk to your doctor about joining a clinical trial. These are studies that test new drugs or treatments to see if they are safe and if they work. They often are a way for people to try new medicine that isn't available to everyone.

If Your Colorectal Cancer Comes Back

Doctors call colorectal cancer “recurrent” if it comes back (recurs) after treatment. It can happen in the same area or in a different part of your body.

Recurrence is most likely in people who had more advanced colorectal cancer the first time.

Treatment may involve:

  • Surgery to take out the cancer. Studies show that this can help people live longer.
  • Chemotherapy with or without radiation, if all the cancer can't be removed in an operation. Sometimes, this shrinks the tumor enough for surgeons to remove it later.
  • Clinical trials