The information on this page was reviewed and approved by
Maurie Markman, MD, President, Medicine & Science at CTCA.

This page was updated on September 21, 2021.

What is colon cancer?

The colon and the rectum make up the large intestine. Cancer of the colon and/or rectum is referred to as colorectal cancer, the fourth most common cancer in the United States. About two-thirds of the 145,000 cases of colorectal cancers diagnosed each year develop in the colon.

Colon cancer occurs when cells in that vital organ mutate and grow out of control. The cancer may also develop when growths on the inside of the colon, called polyps, grow and become cancerous.

The risk of colon cancer increases with age. The average age of a patient diagnosed with this disease is 68. Men have a higher risk than women, and African Americans have a higher risk than other racial demographics.

In order to help reduce the risk of colon cancer and help prevent the disease or catch it early, experts recommend regular examinations and lifestyle changes.

Causes and risk factors for colon cancer

The exact cause of colon cancer is not known, but certain factors are linked to the disease, such as genetics: People with a family history of colon cancer or certain hereditary cancer syndromes have a higher risk, which also increases with age. Other known risk factors for colon cancer include:

  • Diet
  • Smoking
  • Alcohol use
  • Sedentary lifestyle
  • Obesity
  • Diabetes

Learn more about risk factors for colorectal cancer

Signs and symptoms of colon cancer

Colon cancer may show no obvious signs or symptoms in early stages. As the cancer develops, colorectal cancer symptoms may include changes in bowel movements, including frequency, constipation and consistency (loose or watery stools). Other signs and symptoms of colon cancer include:

  • Fatigue
  • Weight loss
  • Blood in the stool
  • Bleeding from the rectum
  • Abdominal pain
  • Bloating
  • A feeling that you are unable to empty your bowels

If the cancer metastasizes, or spreads to other parts of the body, symptoms may develop depending on where in the body the cancer is located. Symptoms of metastatic colon cancer may include:

  • Persistent cough
  • Fatigue
  • Bone pain
  • Shortness of breath
  • Loss of appetite
  • Jaundice
  • Swelling in the hands and feet
  • Changes in vision or speech

Learn more about colorectal cancer symptoms

Types of colon cancer

About 95 percent of all colon cancers are adenocarcinoma. These tumors typically start as a growth in the lining of the colon called a polyp. Polyps may be removed during a routine colonoscopy before they have a chance to develop into cancer.

Other types of colon cancer include:

Learn more about colorectal cancer types

Diagnosing and staging colon cancer

A variety of imaging and laboratory tests are used to diagnose colon cancer and determine the stage of the disease. These tools and procedures include:

These tests may also be used to monitor your response to treatment.

Learn more about colorectal cancer stages and diagnostic procedures

Colon cancer treatments

Treatment may depend on where in the colon the disease is found, as well as its stage and the extent to which it has developed. Treatment options include:

Learn more about treatment options for colorectal cancer

Integrative care for colon cancer

The symptoms of colon cancer and side effects of treatment may impact your quality of life. At Cancer Treatment Centers of America® (CTCA), our team of colon cancer experts not only focus on treating the disease with a wide range of tools and technologies, but we also provide integrative care services to help manage your side effects. These services may include:

Learn more about integrative care

Get expert advice and care

Understanding when symptoms are a sign of something serious and either diagnosing the disease or confirming a previous diagnosis require expertise from professionals trained and experienced in treating colon cancer. At CTCA®, our colon cancer experts treat all stages and types of the disease. 

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