Understand The Different Types Of Colon Cancer Treatment And Their Potential Side Effects

If you've received a colorectal cancer diagnosis, your cancer team will sit down with you to discuss your colon cancer treatment options. It's essential you carefully think about each option and weigh the benefits of each with the potential side effects and risks. Here, you'll learn more about the different treatment options for colon cancer and what to expect from each, so you can make an informed decision with your doctor on which is best for your situation.

Doctors will determine colon cancer treatments by stage and other factors. They might combine them or use one after another.

Different types of colon cancer treatments include:

Have you considered clinical trials for Colon cancer?

We make it easy for you to participate in a clinical trial for Colon cancer, and get access to the latest treatments not yet widely available - and be a part of finding a cure.


Surgery is typically the primary treatment for early-stage colon cancer¹. The type of surgery you'll receive will depend on what stage of cancer you have, where the cancer is in your colon, and the goal of the surgery.

A couple of types of surgery for colon cancer are:

1. Polypectomy and local excision

Certain stage 0 and stage I tumors (early colon cancers) and most polyps are removable during a colonoscopy. A colonoscopy is a procedure the surgeon performs using a colonoscope (a flexible, long tube with an attached video camera on the end). The surgeon inserts it into your rectum and then gently into your colon.

The surgeon can perform a polypectomy and local excision during a colonoscopy.

For the polypectomy, the surgeon removes cancer as part of the polyp, which they cut at its base (it looks similar to a mushroom stem).

A local excision procedure is a little more involved. The surgeon uses tools through the colonoscope to eliminate small cancers on your colon's inside lining, as well as a small amount of healthy tissue from the wall of your colon.

2. Colectomy

A colectomy is a type of surgery where the surgeon removes all or part of your colon. They'll also remove neighboring lymph nodes.

The surgeon performs a colectomy in two ways:

  • Open colectomy: This is where they perform the surgery through one long cut (incision) in your abdomen.

  • Laparoscopic-assisted colectomy: This is where they perform the surgery with special tools, making numerous smaller incisions. They use a laparoscope, a thin, long, and lighted tube with an attached light and a small camera on the end. This allows the surgeon to view the inside of your abdomen.

Potential side effects

Generally, the side effects of colon cancer surgery include tenderness in the area the surgeon operated on and pain.

Surgery might also cause diarrhea or constipation, which typically will go away after some time. If you have a colostomy, you might experience irritation around your stoma (the opening the surgeon made in your belly wall).

After surgery, many individuals have to retrain their bowels. This might take some assistance and time. You should consult with your doctor if you don't regain proper control of your bowel function.

The recovery time will depend on the type of surgery you had and which anesthesia the surgeon used. Since the laparoscopic-assisted colectomy uses smaller incisions than those in an open colectomy, you should recover quicker. You might even be able to leave the hospital sooner than if you had an open colectomy.

Palliative care

This is a form of specialized medical care² that focuses on providing you with a better quality of life when you have a serious illness. It focuses on offering you relief from pain and any other symptoms you're experiencing.

You'll have a team of doctors, nurses, and other trained specialists that will work with you during your palliative care. They'll also work closely with your other doctors and your family to offer an added layer of support that will complement your ongoing care.

The goal of a palliative care team is to improve patients' quality of life and that of their families. Palliative care is often provided alongside curative or other therapy you might be receiving.

When this form of care is used along with various other appropriate treatments, those with cancer might live longer and feel better.


Immunotherapy is a drug therapy that fights cancer using your immune system. The disease-fighting immune system of your body might not attack cancer since the cancer cells make proteins that blind the cells of your immune system and keep them from recognizing the cancer cells. Immunotherapy interferes with this process.

This therapy is typically reserved for advanced colon cancer. The doctor may test your cancer cells to see if there's a good chance they'll respond to this therapy.

The doctor might prescribe drugs known as checkpoint inhibitors³ (PD-1 inhibitors, CTLA-4 inhibitors) if your colon cancer cells test positive for certain gene changes. These can include changes in one of your mismatch repair (MMR) genes or a high level of microsatellite instability (MSI-H). The doctor might use these drugs to treat you if:

  • The surgeon can't remove your cancer with surgery

  • Your cancer has spread to various other parts of your body (metastasized)

  • Your cancer has come back after treatment (recurrent cancer)

Potential side effects

Possible side effects of immunotherapy drugs include:

  • Nausea

  • Loss of appetite

  • Fatigue

  • Constipation

  • Cough

  • Itching

  • Joint pain

  • Skin rash

More severe side effects occur less frequently. Some individuals may experience autoimmune reactions or infusion reactions while receiving these drugs.


Chemotherapy is a form of treatment that uses anti-cancer medications you take by mouth or have injected into your veins. These medications travel through your bloodstream, where they're able to reach most parts of your body.

Chemotherapy is frequently used for treating colorectal cancer. It's often used in stages II, III, and IV⁴.  Although not all doctors agree on whether or not chemotherapy should be used for stage II colorectal cancers.

If your cancer has a high risk of recurring because of specific factors, the doctor might recommend chemotherapy after surgery (adjuvant chemotherapy).

The doctor might use chemo at different times during your colon cancer treatment. For instance, they might give you:

Adjuvant chemotherapy after surgery

The goal of this chemo is to kill any cancer cells potentially left behind during your surgery because they were too small for the surgeon to see. Or kill cancer cells that may have escaped from the primary colon (or rectal) cancer and settled in other parts of your body but are too small for the doctor to see on imaging tests. Adjuvant chemo will lower the chances of recurring cancer.

Neoadjuvant chemotherapy before surgery

The goal of this chemo (sometimes combined with radiation) is to shrink your cancer, making it easier to remove. This is typically done for rectal cancer.

Chemo can be used for advanced cancer that's spread to your other organs like your liver. It helps shrink tumors, easing issues they might be causing. While chemo won't necessarily cure your cancer, it could help you live longer and feel better.

Potential side effects

Chemotherapy's potential side effects will depend on the type of chemo you receive and the dosage. It will also depend on how long you're receiving it. Common chemotherapy side effects can include:

  • Nausea and vomiting

  • Hair loss

  • Diarrhea

  • Weight loss or loss of appetite

  • Skin changes

  • Nail changes

  • Mouth sores

Chemo might also affect your bone marrow's blood-forming cells.

Most chemo side effects go away after some time after you end your treatment. Doctors give chemotherapy in cycles, followed by a period of rest that allows you time to recover from the drugs' effects. Often, cycles are two or three weeks long, but the schedule will vary, depending on which drugs you're using.

Radiation therapy

Radiation therapy uses high-energy x-rays to kill cancer cells. It's often used to treat rectal cancer since this type of tumor typically recurs near where it initially started. Doctors don't commonly use radiation therapy to treat colon cancer. However, they could use it in certain cases.

Radiation therapy with or without chemotherapy might be an option if you have stage III colon cancer⁵ and aren't healthy enough for surgery.

Potential side effects 

Possible radiation therapy side effects could include:

  • Wound healing problems if the doctor gives you radiation before surgery

  • Skin irritation at the area where radiation beams were targeting (could consist of redness or peeling and blistering)

  • Nausea

  • Tiredness/fatigue

  • Rectal irritation, which could cause painful bowel movements, diarrhea, or blood in your stool

  • Bladder irritation, which could cause issues like feeling like you need to frequently go, blood in your urine or pain, or burning while you urinate

  • Bowel incontinence (stool leakage)

  • Fibrosis (stiffening), scarring, and adhesions that lead to the treated area's tissues sticking to each other

  • Sexual issues (vaginal irritation in women and erection issues in men)

Most side effects of radiation therapy should subside once you end treatment, but some issues might not completely go away. If you notice any lingering side effects, speak with your doctor immediately so they can offer you help in relieving or reducing them.

Targeted drug therapy

This type of therapy is a targeted drug treatment that focuses on certain cancer cell abnormalities. The targeted drug treatments block these abnormalities, which cause the cancer cells to die. Most individuals with stage IV colon cancer⁶ will receive targeted therapies with or without chemo to control cancer.

Targeted drugs are typically combined with chemo. They are usually reserved for individuals with advanced colon cancer.

Potential side effects

The side effects of targeted drug therapy will depend on the type you receive. Side effects might include:

  • Bleeding

  • High blood pressure

  • Loss of appetite

  • Fatigue or extreme tiredness

  • Diarrhea

  • Mouth sores

  • Headaches

  • Low white blood cell counts (could lead to increased risk of infections)

  • Tiredness

Choosing which regimen to use will depend on a few factors, including your overall health and any past treatments you've received. If one of these regimens stops working, the doctor will try another one.

Ablation and embolization

When colon cancer has spread, and you have several small tumors in your lungs or liver (stage IV colon cancer⁷), the surgeon can sometimes remove them by surgery or destroy them with other techniques like ablation or embolization.

When the surgeon can remove all primary cancer in your colon (or your rectum) with surgery, they might use ablation or embolization to destroy small tumors in other parts of your body.

Potential side effects


Doctors use ablation techniques⁸ to destroy small tumors (less than 4cm across) rather than removing them during surgery. There are numerous types of ablation techniques.

Potential side effects of ablation therapy are:

  • Fever

  • Abdominal pain

  • Abnormal liver tests

  • Liver infection

  • Bleeding in your abdomen or chest cavity

Severe complications are rare, but they can occur.


The doctor uses embolization⁹ to treat tumors in your liver. During this procedure, they'll inject a substance straight into an artery in your liver to reduce or block the flow of blood to the tumor.

Potential side effects of embolization are:

  • Nausea

  • Fever

  • Abdominal pain

  • Gallbladder inflammation

  • Liver infection

  • Abnormal liver tests

  • Blood clots in your liver's main blood vessels

Typically, there's no need for patients to stay in the hospital for ablation or embolization treatments.

Doctors and specialists

The colon cancer treatment process frequently involves the expertise and input of a multidisciplinary care team¹⁰. This is a group of doctors with various medical specialties related to colon or rectum cancer treatment. They all work together to come up with an effective treatment plan tailored for you specifically.

Since a combination of approaches can treat colorectal cancer, different doctors might guide you through different treatments based on their specialty.

Your treatment plan will determine which doctors will be involved in your care, but these doctors might include:

  • Gastroenterologist: Specializes in digestive tract problem diagnosis and treatment.

  • Surgical oncologist: Specializes in cancer surgery.

  • Colorectal surgeon: Specializes in colon and rectum surgery.

  • Medical oncologist: Specializes in using targeted therapy, chemotherapy, and other cancer treatment drugs.

  • Radiation oncologist: Specializes in using radiation therapy for cancer treatment.

Along with these doctors, you might also meet with other healthcare professionals like nurses, oncology dietitians, pharmacists, social workers, and psychologists as part of your care team.

Your cancer care team might consider various factors before they tailor and develop your treatment plan.

Deciding on treatment 

Receiving a diagnosis of cancer can be emotionally challenging. Most individuals, in time, learn to cope with their situation in their own ways. However, until you find a way that will work for you, you may want to learn as much as you can about your cancer so you'll feel comfortable making a treatment decision.

Talk with your doctor about the type of colon cancer and stage you have as well as your options for treatment and any potential side effects. The more you educate yourself, the more confidence you'll gain in the decisions you make regarding your care.

Clinical trials

Each individual is different and will respond to colorectal cancer treatment differently. With accurate and quick treatment, you can feel good about having hope for your future.

For most individuals, colon cancer doesn't recur, but in around 35% to 40% of individuals¹¹ who have surgery with or without chemo, their cancer might recur within three to five years of treatment.

Regular, standard treatments do stop working. However, there is promise in experimental therapies. Researchers test experimental therapies all the time through clinical trials. They typically aren't available to individuals who aren't part of the trial. While there aren't any guarantees that experimental treatments will help, many people are hopeful and feel they are worth trying.

Scientists and doctors are always looking for better ways to treat colorectal cancer and care for those with this disease. Doctors and scientists create research studies (clinical trials) that involve volunteers to make scientific advances. Every FDA-approved drug has been tested in a clinical trial.

Clinical trials are used for all stages and types of colorectal cancer. Many trials focus on new colon cancer treatments to learn if they're effective, safe, and potentially better than current treatments. Others focus on improving existing treatments.

Clinical trials evaluate different combinations of treatments, new drugs, new treatment methods, and new approaches to surgery or radiation therapy.

Learn about using HealthMatch to find the right clinical trial for you.

Have you considered clinical trials for Colon cancer?

We make it easy for you to participate in a clinical trial for Colon cancer, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

Discover which clinical trials you are eligible for

Do you want to know if there are any Colon cancer clinical trials you might be eligible for?
Have you taken medication for Colon cancer?
Have you been diagnosed with Colon cancer?