Get the facts about colon and rectal cancer

Learn about the symptoms, causes, and screening options for this disease.

Woman in a hospital gown talking to her doctor following a colon exam

Colorectal cancer is a top cause of deaths from cancer in the United States. It is second only to lung cancer. It is on the rise in people aged 50 and younger.

Colorectal cancer affects the colon and the rectum. They are parts of your body’s digestive system. This system is made up of organs that break down food to give you energy.

  • Your colon is a large tube located in the lower part of your abdomen. Waste travels through it before leaving your body. The colon is also called the large intestine.
  • Your rectum collects poop before it leaves your body through the anus. It’s located at the very end of your colon.

Regular screenings can help catch colorectal cancer early. A screening is a test that looks for signs of a disease before symptoms appear. It’s for someone who does not seem sick.

When it is spotted and treated early, it can often be cured.

What is colorectal cancer?
Colorectal cancer starts in the lining of the colon or rectum. It usually begins as a polyp. A polyp is a small growth. Over time, its cells can change to become cancer. These can break free and spread to other parts of the body.

It's important to remember that polyps are often benign. That means they are not cancer. But some may lead to cancer. 

Who’s at risk?
Both men and women are at risk for colorectal cancer. Men have a 1 in 23 chance of developing the disease. Women have a 1 in 25 chance.

Black people have a higher risk than other people.

What causes colorectal cancer?
Certain things may raise your risk of the disease. These are called risk factors. They include the following.

  • Being aged 50 or older
  • Being overweight
  • Not moving enough
  • Eating too much red or processed meat
  • Smoking
  • Heavy drinking
  • Having inflammatory bowel disease, an illness that affects the digestive system

Your risk is also increased if you have a family history of the disease. That means a family member has had:

  • Colon cancer
  • Rectal cancer
  • Polyps

Are there any symptoms?
Colorectal cancer is sometimes called a "silent killer." That’s because it often has no early symptoms. They may appear when the disease has gotten worse. It may have spread to other parts of the body.

Here are symptoms you may see:

  • Watery, loose poop that lasts for a long time
  • Being unable to poop for a long time
  • Feeling like you still have to poop after you’ve just gone
  • Rectal bleeding, which may be seen on toilet paper or in poop
  • Blood in your poop, which can be dark red or black like tar
  • Changes in poop
  • Losing weight without meaning to
  • Weakness and fatigue
  • Pain or cramping in the belly area
  • Anemia, or low red blood cells which carry oxygen throughout your body

Sometimes, symptoms can be confused for other medical issues.

What are the screening options?  
Screening is very important. It can help healthcare providers (HCPs) find polyps. They can be removed early, before cancer develops. It can also help HCPs diagnose cancer.

  • For people at average risk, screening should start at age 45.
  • For people at higher risk, screening should start sooner. Talk to an HCP about when to begin.

Here are some of the most common types of screenings.

Colonoscopy: Experts prefer this to other ways of screening. During it, a tube with a camera is placed into the rectum and colon. There, it is used to check for polyps. If polyps are found, they are usually removed for testing. This should be done every 10 years, or more often depending on the findings. 

Many people put off getting a colonoscopy. They think it will be uncomfortable and take a lot of time. But it is usually short and painless. Most are done when you are sedated. That means you are given drugs that make you sleepy. You don’t feel anything as it happens.

It’s true that preparing the night before can be uncomfortable. You must drink a liquid to clean out the colon. This liquid causes diarrhea for a short time. Diarrhea is loose, watery poop.

Stool tests: These tests look for blood or cancer cells in poop. You collect a sample at home. Then you mail it to a lab to be examined. This should be done every 1 to 3 years, depending on the test.

Flexible sigmoidoscopy: A tube is placed in the rectum and colon to check for polyps. This should be done every 5 years.

What are the treatments?
If you are diagnosed with colorectal cancer, you will receive treatment. This treatment will be decided by three things.

  • The stage, or how far it has grown and spread
  • The location, or where it is in the body
  • The type of cancer cells

There are many different types of treatment. They include the following.

  • Surgery to remove the cancer
  • Radiation therapy, or high-dose X-rays that kill cancer cells
  • Chemotherapy, or drugs that kill cancer cells but can also damage healthy cells
  • Targeted therapy, or drugs that kill cancer cells but avoid damaging healthy cells
  • Immunotherapy, or drugs that boost the immune system

You can also use more than one kind of treatment. This is called combination therapy.

How can you lower your risk?
You can’t control your age or family history. But there are other steps you can take to lower your risk of colorectal cancer. The most important step is getting screened.

Here are other steps.

  • Try to maintain a healthy weight for your body.
  • Quit smoking if you smoke.
  • Stay active and exercise regularly, as you are able.
  • Limit red meat like beef and pork.
  • Limit processed meats like hot dogs and bacon.
  • Limit processed foods like breakfast cereal and bagged snacks.
  • Try to include plenty of fruit, vegetables, and whole grains in your diet.
  • Limit alcohol. Men should have no more than 2 drinks each day. For women, it’s 1 drink each day.

Always go to appointments with your HCP. Taking care of your overall health can also lower your risk.

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