Colon cancer occurs when cells in your large intestine grow out of control. Treatment can vary by the stage and type of colon cancer.

Colon cancer is a type of cancer that starts in your colon (large intestine).

It’s often referred to as colorectal cancer. However, colorectal cancer is a group of cancers that includes both colon cancer and rectal cancer, which begins in the rectum.

According to the Centers for Disease Control and Prevention (CDC), colorectal cancer is the fourth most common type of cancer in the United States.

The American Cancer Society (ACS) estimates that about 1 in 23 males and 1 in 25 females will develop colorectal cancer during their lifetime.

Approximately 7 in 10 cases of colorectal cancers begin in the colon.

Learn more about colon cancer stages, causes, and risk factors — plus resources to help you find support.

There are several types of colon cancer. These vary based on the different types of cancerous cells and where they’re located in the digestive tract.

The most common type of colon cancer starts from adenocarcinomas, according to the ACS. Adenocarcinomas form within the cells that make mucus in either the colon or rectum.

Less commonly, colon cancers are caused by other types of tumors, such as:

Doctors use staging as a general guideline to help them determine how far along the cancer is. This could help them develop the best treatment plan and better predict your long-term outlook.

Stage 0 colon cancer is the earliest stage, and stage 4 is the most advanced stage.

Here’s how the stages are defined:

  • Stage 0: Also known as carcinoma in situ, this stage involves abnormal cells that are only in the inner lining of the colon.
  • Stage 1: The cancer has penetrated the lining, or mucosa, of the colon and may have grown into the muscle layer. It hasn’t spread to nearby lymph nodes or other parts of the body.
  • Stage 2: The cancer has spread to the walls of the colon or through the walls to nearby tissues, but hasn’t affected the lymph nodes.
  • Stage 3: The cancer has moved to the lymph nodes but not to other parts of the body.
  • Stage 4: The cancer has spread to other distant organs, such as the liver or lungs.

Learn more about the stages of colon cancer.

You might not experience colon cancer symptoms at all, especially in the early stages.

If you do experience symptoms of colon cancer, they may include:

It’s important to note that many of these symptoms may also be caused by other, less serious, conditions.

As such, it’s a good idea to see a doctor if you’ve had any of these symptoms for 3 weeks or more. You and the doctor can discuss your symptoms and decide if colon cancer screening is appropriate.

Learn more about the symptoms of colon cancer.

An early diagnosis of colon cancer gives you the best chance of curing it.

Since colon cancer often has no symptoms during the early stages, it’s often caught during routine screenings like colonoscopy.

The U.S. Preventive Service Task Force (USPSTF) and the ACS recommend starting colon cancer screening at age 45 years.

A doctor will start by getting information about your medical and family history.

They’ll also perform a physical exam. They may press on your abdomen or perform a rectal exam to determine whether lumps or polyps are present.

A variety of other tests are recommended at different yearly intervals for the screening of colon cancer, including:

  • Fecal tests: Guaiac-based fecal occult blood test (gFOBT) and fecal immunochemical test (FIT) are recommended every 1 year.
  • Sigmoidoscopy: Every 5 years.
  • Virtual colonoscopy: Every 5 years.
  • Colonoscopy: Every 10 years.

The Shield™ Blood Test by Guardant Health was approved by the Food and Drug Administration (FDA) in July 2024 for the screening of colorectal cancer.

A healthcare professional may recommend more frequent screening if you have a higher risk of developing colon cancer.

Products to try

Some at-home tests may also be used to help detect blood in the stool, an important symptom of colon cancer. These may include:

Shop for them online and learn more about the pros and cons of at-home tests.

Treatment for colon cancer will depend on several factors, such as the stage and type of cancer, and whether it’s spread to other parts of your body.

In stages 0, 1, and 2 of colon cancer, it’s often possible for a surgeon to remove cancerous polyps through surgery. If the polyp hasn’t attached to the wall of the bowels, you’ll likely have an excellent outlook.

If your cancer has metastasized, you may require other types of treatment, such as:

Learn more about the treatment options for colon cancer.

The exact causes of colon cancer are still unknown, but researchers have identified several factors that may increase your risk of developing colon cancer.

Genetics

Colon cancer may be caused by genetic mutations that can either be inherited or acquired. These mutations don’t guarantee you’ll develop colon cancer, but they do increase your chances.

Some genetic conditions associated with colon cancer include:

Some mutations may cause abnormal cells to accumulate in the colon lining, forming polyps. These are small, benign growths. However, untreated polyps can become cancerous. Removing these growths through surgery can be a preventive measure.

Risk factors you can’t change

Some factors that increase your risk of developing colon cancer can’t be changed. For instance, your age, ethnicity, and family health history can all impact your risk of colon cancer.

Risk factors you can’t control include:

Certain risk factors for colon cancer, such as family history and age, aren’t preventable.

However, certain lifestyle factors that may contribute to colon cancer are preventable, and changing them might help lower your overall risk of developing this disease.

You can reduce your risk by:

Getting a colonoscopy or other cancer screenings when you turn 45 years old could help detect colon cancer. This is important, as early diagnosis and treatment could help prevent further complications.

It can be alarming and stressful to receive a diagnosis like colon cancer. Fortunately, colon cancer is treatable, especially when detected early.

The life expectancy for colon cancer is provided as a 5-year life expectancy. This compares how likely a person with colon cancer is to be alive 5 years after receiving their diagnosis compared to people without colon cancer.

Below are the 5-year survival rates for colorectal cancer, provided by the ACS:

Colon cancer stage at diagnosisSurvival rate
Stage 0 and Stage 191%
Stage 2 and Stage 373%
Stage 413%
Overall 63%

It’s important to note that survival rates are continuing to increase as new cancer treatments are being developed.

That said, the ACS notes that colorectal cancer cases have risen by 1.3% among younger people between 2008 and 2017.

How can I get support for colon cancer?

No matter what happens on your treatment journey, you’ll need support along the way. It’s important to talk with your medical team and loved ones and to feel comfortable reaching out for help.

Here are some resources to start building a support system:

  • The Colorectal Cancer Alliance Helpline (877-422-2030) is a free service that can connect you to resources and peer support.
  • The Colorectal Cancer support group live chatmeets every weekday between 12 pm and 1 pm EST.
  • Blue Hope Nation is a supportive Facebook group for colon cancer patients and family members.
  • CancerCare offers a Colorectal Cancer Patient Support Group led by an oncology social worker.
  • Fight Colorectal Cancer offers a resource library for people with colon cancer including videos, podcasts, and more to support you through treatment and beyond.

Can colon cancer be cured?

If colon cancer is diagnosed in the early stages, surgery may be able to completely remove the cancerous polyp.

Does colon cancer spread fast?

The progression of colon cancer varies for each person. However, the ACS notes that colon cancer usually takes years to develop and spread. Early detection and treatment are key to preventing further spreading and complications.

How bad is stage 1 colon cancer?

Many people don’t experience symptoms of colon cancer during stage 1. However, it’s possible to experience changes in your bowel habits, rectal bleeding, fatigue, and unexplained weight loss. It’s important to see a doctor if you experience these symptoms.

Colon cancer is a type of cancer that begins in the colon.

In the early stages, you may not experience any symptoms of colon cancer, which makes it hard to diagnose.

However, regular screening could help catch colon cancer early, leading to prompt treatment to reduce complications.