This page was reviewed under our medical and editorial policy by
Maurie Markman, MD, President, Medicine & Science
This page was reviewed on June 9, 2022.
Following a colon cancer diagnosis, the care team will work with the patient to develop a treatment plan depending on the stage of colon cancer. Stage refers to how much the cancer is localized or has spread outside its original area.
Surgery for colorectal cancer is typically the first treatment for localized colon cancer. Chemotherapy may also be an option. Additional treatments may be recommended for distant colon cancer (cancer that has spread to other organs).
With colon cancer, stage 0 describes cancer that is located in the colon’s inner lining but has not spread beyond it. Cancer at this stage is also called carcinoma in situ. For stage 0 colon cancer, surgery is the most common treatment, and it’s typically the only treatment needed. This often means removing the colon polyp (a group of cells), or the area with cancer in the colon, in a procedure called a polypectomy. Doctors may perform this procedure during a colonoscopy.
If the cancer is too large to be removed, the surgeon may perform a partial colectomy, which removes part of the colon. This procedure removes the cancerous section of the colon and adjacent lymph nodes. The surgeon may join the healthy parts of the colon after removing the cancer in a procedure called anastomosis.
Stage 1 colon cancers have moved into the layers of the colon wall, but they haven’t spread beyond the colon wall or to nearby lymph nodes.
If a polyp is discovered, it's removed during a colonoscopy, which may be the only treatment needed.
The patient may need more surgery if:
Surgery for stage 1 colon cancer typically involves a partial colectomy, which removes part of the colon.
Stage 2 colon cancers have grown through the colon wall and may have spread near other tissue, but not to the lymph nodes.
As with stage 0 and stage 1, surgery is often the first-line treatment for stage 2 colon cancer, and it may include a partial colectomy, as well as surgery to remove nearby lymph nodes.
Chemotherapy also may be used after surgery. This is more common if the cancer is more likely to recur.
The cancer has a higher risk of recurring include if it:
A type of test called microsatellite instability (MSI) or mismatch repair (MMR) testing, which checks a tumor for gene changes, also may help determine whether chemotherapy may be useful.
The use of chemotherapy for stage 2 colon cancer is not supported by all oncologists because surgery alone may be sufficient to treat the cancer. Speak with the care team about the benefits and risks of chemotherapy after surgery for stage 2 colon cancer.
Radiation therapy may also be recommended to kill remaining cancer cells left behind after surgery.
Stage 3 colon cancer has spread to nearby lymph nodes, but not other areas of the body.
The most common treatment for stage 3 colon cancer includes a partial colectomy and removal of nearby lymph nodes, along with adjuvant chemotherapy. Clinical trials exploring new chemotherapy treatments may be another option for qualified stage 3 colon cancer patients.
Radiation therapy along with chemotherapy may be recommended if the cancer cannot be completely removed. Radiation therapy may also be used for stage 3 colon cancer to:
Stage 4 (metastatic) colon cancer has spread from the colon to distant organs and tissues, including:
Treatments for stage 4 colon cancer vary, but may include those listed below.
Surgery: Doctors may recommend surgery to extend the patient’s life, especially if the cancer has spread to only a couple of small areas in the liver or lungs and can be removed with surgery. Typical surgical treatments include a colectomy, which removes all or part of the colon, or a diverting colostomy, which allows waste to exit the body through the abdomen.
Chemotherapy: Chemotherapy is typically used in combination with surgery to treat stage 4 colon cancer. If the cancer is too large to be removed with surgery, chemotherapy is often used before surgery to shrink the tumors. It also may be used after surgery to kill remaining cancer cells.
Targeted therapy: These drugs are designed to be more precise than chemotherapy, by targeting certain features unique to specific cancer cells or that influence their behavior. Targeted therapy may be used alone or with chemotherapy to make it work better.
Radiation therapy: This treatment is typically used to relieve or help prevent colon cancer symptoms, such as pain. Radiation therapy may also be used to treat colon cancer that spreads to the lungs or bone.
Recurrent colon cancer is cancer that’s returned after initial treatment. This type of cancer is sometimes difficult to treat.
Surgery and chemotherapy are the most common options for treating recurrent colon cancer. If the cancer is local, meaning it’s limited to the area around the original tumor, doctors may recommend chemotherapy to make the tumor smaller before removing it surgically. Chemotherapy may also be used again after surgery to kill remaining cancer cells.
If the recurring cancer is in a distant organ, such as the liver, the doctor may recommend an ablation (a treatment that destroys liver tumors without surgery) or embolization (a procedure to cut off a tumor’s blood supply).
If the cancer has certain genetic markers, the care team may also recommend immunotherapy, a type of cancer treatment that helps the immune system recognize and attack cancer.
Radiation therapy may be used to help relieve symptoms caused by recurrent cancers.