A colon with what appears to be a tumor

Colon Cancer

The term colon cancer is sometimes used interchangeably with colorectal cancer because colon and rectal cancers share common features. The rectum and colon make up the large intestine. Colorectal cancer is the fourth most common cancer in the United States, and it’s the second leading cause of cancer-related deaths.

Most colon cancers are caused by growths within the inner lining of the colon, called polyps. The chance of a polyp developing into cancer depends on factors, like the type of polyp (adenomatous polyps are considered precancerous) or if it has abnormal cells (called dysplasia).

Through routine screenings, most polyps can be found and removed before they turn into cancer. Screening tests include visual tests (colonoscopy) and at-home stool tests (fecal immunochemical test).

Frequently Asked Questions

  • What causes colon cancer?

    Most colon cancer develops from polyps with abnormal cells that start growing uncontrollably. There are several risk factors that increase a person's chance of developing colon cancer, such as leading a sedentary lifestyle, smoking, heavy alcohol intake, having a family history of colon cancer, or having an inflammatory bowel disease (IBD).

  • How do you prevent colon cancer?

    The most important step is to talk to your doctor about colon cancer screenings. Those considered average risk are encouraged to begin screenings at age 45.1 Lifestyle factors that may also be helpful include moderating your meat consumption, eating more produce and fiber, getting moderate to vigorous exercise, avoiding smoking, and limiting alcohol consumption.

  • What are the symptoms of colon cancer?

    Symptoms may not occur initially, but as the disease progresses, a person may notice a change in their bowel habits (persistent diarrhea or constipation) or dark or bright red blood in their stools. Other symptoms may include abdominal pain, cramping, weight loss, loss of appetite, or fatigue.

Key Terms

The Stages of Colon Cancer

Explore interactive models that show how colon cancer can metastasize (spread) in the large intestine, and how the disease changes as it progresses.

Stomach pains
Cecum Cancer May Be Hard to Diagnose
Caucasian doctor and patient using digital tablet at home
How to Spot a Carcinoid Tumor Before It Spreads
Man throwing up in toilet with glass of water in foreground
Signet Ring Cell Adenocarcinoma of the Colon and Rectum
Inside of a colon
Can You Keep Your Colon Happy and Healthy?
The inside of a vein showing white blood cells
What Do Neutrophils Tell Us About Cancer Treatment?
Basophil
Basophils Are Your Body's Natural Tick Fighter
Elderly p. consulting, dialogue
How Mucinous Adenocarcinoma Differs From Other Colon Cancers
Conceptual image of a platelet.
What Your Mean Platelet Volume (MPV) Means
Eosinophil; white blood cell (leukocyte), 400X at 35mm. Human blood smear. Eosinophils have a bilobed nucleus, and large, reddish cytoplasmic granules. Increased numbers of eosinophils (eosinophilia) occur in allergies. 1-3% of the total # of white
The Role Eosinophils Play in Cancer
Man lying in hospital bed
What Is Leiomyosarcoma?
Young Girl Receiving Chemotherapy Treatment
Colon Cancer Can Be Fatal for Children
Large intestine
What Does the Large Intestine or Colon Do?
Doctor speaking with patient
What are Macrophages and How Do They Help Your Immune System?
A man suffering stomach pains
The Invisible Danger of Colorectal Lymphoma
Colon cancer cell
The 4 Stages of Colon and Rectal Cancer
Senior man gestures while speaking with a healthcare provider.
Signs of Colon Cancer in Men
older man on toilet googling on his smart phone
Colon Cancer and Poop: Signs to Watch Out For
Doctor holding a colonoscope preparing for a colonoscopy
An Overview of Adenomatous Polyps
Doctor discussing prescription with senior patient
How Can Your Colon Cancer Pain Symptoms Be Relieved?
Polyp removal, artwork
What You Should Know About Polyps and Colon Cancer
Smiling African American woman attaching earring
Discover the Link Between Cancer and Anemia
Interior Of Bathroom
What Does a Bloody Stool Mean?
Rectal prolapse
Do You Know the Signs of Rectal Prolapse?
a doctor reviewing medical chart with senior man
What Are the Causes of Rectal Itching?
Close up of pants around businessman's ankles in restroom
Rectal Cancer Signs and Symptoms
Human colon, illustration.
The Best At-Home Colon Cancer Tests in 2021
Doctor and patient
What Is Gardner Syndrome?
Colon polyp being removed
What Is a Colon Polyp?
Cropped hand of laboratory technician holding blood sample for medical testing
Lynch Syndrome Is Hereditary and Can Cause Colon Cancer
Hand refusing bread
Does Celiac Disease Increase or Decrease the Risk of Colon Cancer?
senior Asian couple reading book
Find Out the Number One Risk Factor for Colon Cancer
toilet paper
What Are Potential Causes of Blood in Your Stool?
Colon cancer stool screening test
What Are the Options for Colon Cancer Screening?
PET Scan machine
How Do PET Scans Work in Staging Colorectal Cancer?
Male patient and doctor in discussion in exam room
What to Expect From a Colon Biopsy
A rectal cancer cell
Rectal Cancer Survival Rates and the Factors that Influence Them
Are You Having a Fecal Occult Blood Test? Here's What to Expect
A slide on a lit up microscope
How a Colon Biopsy Is Performed
Technician holding blood sample for checking CEA in a patient with cancer
What Is the Carcinoembryonic Antigen (CEA) Blood Test?
Man talking with doctor
Stool Test Types and Options
Doctor sitting in office with patient talking and holding paper. Differences between colorectal and colon cancer
Is There a Difference Between Colorectal and Colon Cancer?
empty toilet paper rolls
How Do You Know When Your Bowel Prep Is Complete?
Colon cancer screening
Are There Financial Assistance Programs for Colon Cancer Screening?
Doctor talking to patient in office
What Can Cause a False Positive Medical Test Result?
A doctor goes over a patient''s x-ray, screening for colon cancer.
What to Expect With a Barium Enema
Concerned young man
Young People and Colon Cancer Diagnosis
Doctor talking to patient in doctor's office
Anemia Is Among the Most Frequently Overlooked Signs of Colon Cancer
Woman on a telemedicine call with her doctor.
What to Know About Telehealth for Colon Cancer
Doctor and patient discuss prognosis
How Long Can I Live If I Get Colon Cancer?
Close-up of surgeon putting on surgical gloves in operating theater
How to Prepare for a Proctectomy
Boiled egg
What to Eat on a Low-Residue Diet
Colostomy bags
How to Change Your Colostomy Pouch After Surgery
Nurse helping patient with chemotherapy
Understand Why More People Are Refusing Chemotherapy
man receiving chemotherapy
Benefits of Pre-Surgery Chemoradiation for Rectal Cancer
Surgeons performing in an operating room
What is the HIPEC Procedure for Colon Cancer?
intravenous administration by nurse
Monoclonal Antibody Therapy to Combat Colon Cancer
Smiling doctor looking at patient in hospital ward
Recovery After Bowel Surgery Can Be Both Physical and Emotional
Liver cancer, artwork
Focusing on the Treatment of Liver Metastases
oncologists looking at MRI
Treating Bowel Obstruction Due to Colon Cancer
bowl of yogurt with berries on top
What You Can Eat After Colectomy Surgery
Page Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Cancer Society. Can colorectal cancer be prevented? Updated June 9, 2020.

  2. National Cancer Institute. Cancer stat facts: cancer of any site.

  3. Anderloni A, Jovani M, Hassan C, Repici A. Advances, problems, and complications of polypectomy. Clin Exp Gastroenterol. 2014;7:285-96. doi:10.2147/CEG.S43084

Additional Reading