How Colon Cancer Is Treated

There are two main categories of treatments for colon cancer. Local treatments target one specific area, such as surgery or radiation. Systemic, or body-wide, treatments have a much wider net and include chemotherapy or targeted biologic therapies. Depending on your physical health, stage of cancer, and personal choice, you may elect one treatment or a combination.

Early detection and treatment of colon cancer may improve your prognosis (treatment outcome) and quality of life. In fact, according to the American Cancer Society, when stage 1 colon cancer is detected and treated early, 92 percent of people are alive five years or more after treatment. 

Surgery

Surgical removal is the treatment of choice for most early-stage colon cancers, but the type of surgery depends on factors like how far the cancer has spread and wherein the colon it is located. 

Polypectomy

Many early colon cancers (stage 0 and some early stage 1 tumors) and most polyps can be removed during a colonoscopy. During a polypectomy, the cancerous polyp is cut at the stalk using a wire loop instrument that is passed through the colonoscope, which is a long, flexible tube with a camera and light at its tip. 

Colectomy

This form of colon cancer surgery involves a specialist, called a colorectal surgeon, removing a portion (or portions) of the intestine. Rarely, a total colectomy, in which the entire colon is removed, is needed to treat colon cancer. A total colectomy may be used to treat those with hundreds of polyps (like people with familial adenomatous polyposis) or those with severe inflammatory bowel disease.

There are two ways a colectomy can be performed—laparoscopically or open—and the option your surgeon chooses depends on factors like the size and location of the colon cancer, as well as the surgeon's experience. A laparoscopic procedure requires a much smaller incision than an open colectomy, so recovery is generally faster.

During a colectomy, the diseased section of the colon is removed, along with an adjacent part of the healthy colon and lymph nodes. Then, the two healthy ends of the bowel are reattached. The surgeon's goal will be for the patient to return to the most normal bowel function possible. This means that the surgeon will take out as little of the colon as possible.

Some of the tissue removed from the lymph nodes is taken to a pathology lab and examined under a microscope by a pathologist. The pathologist will look for signs of cancer in the lymph tissue. Lymph nodes conduct a fluid called lymph to cells in the body. Cancer cells tend to gather in the lymph nodes, so they are a good indicator for determining how far cancer has spread. The removal of lymph nodes also reduces the risk of cancer reoccurring.

In some cases, like if surgery needs to be done urgently because a tumor is blocking the colon, a reconnection of the healthy bowel (called an anastomosis) may not be possible. In these cases, a colostomy may be necessary.

It's important to note that in some cases, a surgeon will not know how far cancer has progressed before beginning the surgery; in others words, there is a chance more colon will have to be removed than previously thought. 

Colostomy Surgery

A colostomy is created when part of the large intestine is inserted through an opening in the abdominal wall. The part of the colon that is on the outside of the body is called a stoma (Greek for "mouth"). The stoma is pink, like gum tissue, and does not feel pain. An external bag worn on the abdomen is then necessary to collect waste. The bag is emptied several times a day and changed on a regular basis.

Most colostomies that are done to treat colon cancer are temporary and are only necessary to allow the colon to heal properly after surgery.

During a second surgery, the healthy ends of the colon are reattached together and the stoma is closed up. Rarely, a permanent colostomy is needed. 

Preparation and Recovery

Every medical procedure carries risks and benefits. Make sure you talk with your doctor about them and ask questions so you feel confident about your treatment decision. Some of the risks associated with bowel surgery include:

  • Bleeding
  • Infection
  • Blood clots in the legs
  • Leaking anastomosis
  • Incision dehiscence (opening of the abdominal incision)
  • Scarring and adhesions

Prior to any surgery on the colon, it must be squeaky clean on the inside. This is accomplished through a complete bowel preparation, similar to the one you may have had for your colonoscopy.

You will be required to stay in the hospital for at least a few days following bowel resection. The time in the hospital will allow any surgical incisions to begin healing, while nurses and doctors monitor hydration, nutrition, and other needs after surgery, like pain control. 

Depending on the surgery, drains may be placed. These drains allow excess fluids, such as blood, to leave the abdomen. The drains may be removed before discharge from the hospital. If you had a colostomy inserted during the surgery, the nursing staff will teach you how to care for your colostomy bag and stoma before you go home.

Of course, following any surgery, be sure to listen to your body and report any unusual symptoms to your surgeon. Call your doctor immediately if you have:

  • Fever
  • Increasing pain
  • Redness, drainage or tenderness around incision sites
  • Non-healing areas of incision
  • Nausea, vomiting
  • Blood in the stool or colostomy bag
  • A cough that does not go away
  • Yellow eyes or skin

Local Therapy

In certain cases, radiation therapy may be used in the treatment of colon cancer. Radiation therapy uses a specific type of X-ray to kill cancer cells and can be used in conjunction with chemotherapy and surgery for colon cancer. A radiation oncologist will provide targeted radiation treatments to reduce any painful symptoms of cancer, kill any remaining cancer cells suspected after surgery or from recurrence, or as a form of treatment if a person cannot tolerate surgery.

Radiation therapy sessions usually occur five days per week and are painless procedures, although a person may experience skin irritation (like a sunburn) at the radiation site, as well as nausea or vomiting at some point during treatment.

Systemic Therapy

Unlike radiation, these options affect the entire body, instead of zeroing in on a specific area.

Chemotherapy

Chemotherapy drugs travel throughout the body and kill cells that are dividing (growing or duplicating) rapidly. Though the treatment doesn't distinguish between cancerous cells and healthy, fast-dividing cells (like those in hair or nails), the latter will be replaced upon completion of chemotherapy.

The majority of people with stage 0 or stage 1 colon cancer will not require chemotherapy. For those with later stage colon cancer, chemotherapy may be given prior to surgery to shrink the tumors before physical removal. Chemotherapy is also sometimes used to shrink tumors throughout the body when systemic metastasis has occurred (in stage 4 cancer). Your doctor may also advise you to undergo chemotherapy after surgery to kill any remaining cancer cells and decrease the chances of cancer recurrence.

Chemotherapy may be administered in conjunction with other colon cancer treatments (for example, surgery or radiation) or by itself. A medical oncologist (the cancer doctor who orders the chemotherapy) will take several factors into consideration when choosing the best chemotherapy options, including the stage and grade of cancer and your physical health.

Drugs and treatment regimens: Intravenous chemotherapy drugs are given by injection through a vein, whereas oral chemotherapy drugs are given by mouth with a pill.

Most intravenous chemotherapy drugs are given in cycles, which are followed by a period of rest. Your doctor will take your health, your cancer’s stage and grade, the chemotherapy drugs used, and the treatment goals into consideration while deciding how many treatments are right for you.

After chemotherapy is started, your doctor will have a better idea of how long you will need the treatment based on your body’s response to the medications.

Some of the chemotherapy drugs used to treat colon cancer include:

  • 5-FU (fluorouracil)
  • Eloxatin (oxaliplatin)
  • Xeloda (capecitabine)
  • Camptosar (irinotecan, irinotecan hydrochloride)
  • Trifluridine and tipiracil (Lonsurf), a combination drug 

The side effects of chemotherapy for colon cancer are multitudinous, but most can be eased with other medications. You may experience:

  • Nausea, vomiting, and loss of appetite
  • Hair loss
  • Mouth sores
  • Diarrhea
  • Low blood counts, which can make you more prone to bruising, bleeding, and infection
  • Hand-foot syndrome, which is a red rash on the hands and feet that may peel and blister (may occur with capecitabine or 5-FU)
  • Numbness or tingling of the hands or feet (may occur with oxaliplatin)
  • Allergic or sensitivity reaction (may happen to occur with oxaliplatin)

Targeted Therapy

Targeted treatments for colon cancer are given concurrently with chemotherapy, typically intravenously, once every one to three weeks.

These drugs usually recognize the protein growth factors that cover cancerous cells, such as the vascular endothelial growth factor (VEGF) or the epidermal growth factor receptor (EGFR), or proteins located inside the cell. Some of these drugs are antibodies administered intravenously, which specifically attack the proteins they bind to. They only kill cells covered in these factors and have the potential for fewer side effects than chemotherapy agents. 

Some of these agents are given concurrently with chemotherapy once every one to three weeks, including:

  • Avastin (bevacizumab)
  • Erbitux (cetuximab)
  • Vectibix (panitumumab)
  • Zaltrap, Eylea (aflibercept)

Others Cyramza (ramucirumab) may be administered alone. Tyrosine kinase inhibitors, such as Stivarga (regorafenib), are administered orally.

All treatments present a risk of side effects. The benefits of your treatment should outweigh the risks. Your doctor will work with you closely and tailor your treatment program to your needs.

That said, the most common side effect of the drugs that target EGFR are an acne-like rash on the face and chest during treatment. Other potential side effects include headache, fatigue, fever, and diarrhea. For the drugs that target VEGF, the most common side effects include:

  • High blood pressure
  • Extreme tiredness (fatigue)
  • Bleeding
  • Increased risk of infection
  • Headaches
  • Mouth sores
  • Loss of appetite
  • Diarrhea

Immunotherapy

For people with advanced colon cancer or cancer that is still growing despite chemotherapy, immunotherapy may be a treatment option. The purpose of immunotherapy is to use a person's own immune system to attack the cancer. Two types of immunotherapy drugs include:

  • Keytruda (pembrolizumab)
  • Opdivo (nivolumab)

Some potential side effects of these drugs include:

  • Fatigue
  • Fever
  • Cough
  • Feeling short of breath
  • Itching and rash 
  • Nausea, diarrhea, loss of appetite, or constipation
  • Muscle and/or joint pain

Specialist-Driven Procedures

If the colon cancer has spread to other organs, like to the liver or lung (called metastatic colon cancer), surgery may be performed to remove one or more of those spots. Many factors go into the decision of how to best treat metastatic colon cancer, including the number of metastatic lesions, where they are located, and a patient's goals of care. 

Non-surgical procedures may also be used to destroy or shrink metastatic lesions.

These non-surgical procedures include:

  • Cryosurgery, which kills the cancerous cells by freezing them
  • Radiofrequency ablation, which uses energy waves to destroy (burn) cancer cells that have metastasized to other organs, such as the liver or lungs
  • Ethanol ablation, which destroys the cancer cells with an injection of alcohol

Palliative Care

Palliative treatment, also known as symptom management or comfort care, is focused on subduing uncomfortable symptoms from a chronic or terminal disease. In colon cancer, palliative treatment can help you cope physically, emotionally, and spiritually during your fight.

When people receive palliative treatment, the medications, procedures, or surgery elected are intended to help with symptom management, as opposed to providing a cure for cancer.

Some common symptoms and sources of discomfort that a palliative care doctor will focus on include:

  • Anxiety, depression, and confusion
  • Shortness of breath and fatigue
  • Loss of appetite and weight loss
  • Constipation, diarrhea, and bowel obstruction
  • Lymphedema
  • Nausea and vomiting

Furthermore, pain management is a top priority in palliative care. You can receive pain management from your primary doctor, oncologist, or even a pain management specialist. Interventions to alleviate or control your cancer pain may include:

  • Pain medicines (prescription, over-the-counter drugs, and complementary medicines)
  • Tricyclic antidepressants or anticonvulsants (for nerve-based pain)
  • Interventional procedures (epidurals, nerve blocks)
  • Physical or occupational therapy
  • Counseling and biofeedback

Complementary Medicine (CAM)

Research suggests that combining chemotherapy with Chinese herbal therapies and other vitamins and supplements (for example, antioxidants) can improve survival rates in colon cancer when compared to chemotherapy alone. 

For instance, a large study in California found that conventional therapy combined with Pan-Asian medicine plus vitamins reduced the risk of death in stage 1 colon cancer by 95 percent; stage 2 colon cancer by 64 percent; stage 3 colon cancer by 29 percent; and stage 4 colon cancer by 75 percent (as compared to conventional therapy with chemotherapy/radiation). 

While incorporating complementary medicine into your colon cancer care is a reasonable idea, be sure to only do this under the guidance of your oncologist. This will help prevent any unwanted side effects or interactions. 

How You Can Prevent Colon Cancer
Was this page helpful?
View Article Sources