Rectal Cancer

Overview

What is rectal cancer?

Rectal cancer develops when cancer cells form in the rectum (the last six inches of the large intestine). The rectum is a chamber that’s located between the colon and the anus.

Who does rectal cancer affect?

Rectal cancer affects both men and women, though men are slightly more likely to develop the disease. In most cases, people diagnosed with the disease are over the age of 50. However, it’s possible for teens and young adults to develop rectal cancer, as well.

How common is rectal cancer?

Approximately 5% of people will develop rectal cancer at some point in their lives. Of those people, about 11% will be under the age of 50.

What is the first stage of rectal cancer?

During Stage I, rectal cancer has grown into the deep layers of the rectal wall but has not spread to nearby areas. People with Stage I rectal cancer may not experience any warning signs or symptoms. That’s why routine colonoscopy screenings are so important.

What is the difference between rectal cancer and other cancers affecting the large intestine?

There are different types of cancers and diseases that can affect the rectum. These include:

  • Colorectal (colon) cancer: This is a broad term describing cancers of the colon, rectum or both. Colorectal cancer is the third most common form of cancer in the U.S.
  • Hereditary non-polyposis colorectal cancer (HNPCC): This condition causes a mutation in an important gene — one that’s inherited or passed down from a parent to a child. About 5% of people with colorectal cancer have HNPCC.
  • Familial adenomatous polyposis (FAP): This rare hereditary condition causes multiple precancerous polyps to form in the large intestine. People with FAP usually develop polyps in their late teens or early 20s. The polyps become more problematic with age, increasing the risk for colorectal cancer.

Symptoms and Causes

What are the warning signs of rectal cancer?

In many cases, rectal cancers don’t cause symptoms at all. However, some people may notice certain warning signs. Rectal cancer symptoms may include:

What is the main cause of rectal cancer?

The exact cause of rectal cancer is unknown. However, there are certain risk factors that increase your chance of developing the disease, including:

  • Age: Like most cancers, the risk of rectal cancer increases with age. The average age of diagnosis is 63 for both men and women.
  • Gender: Men are slightly more likely to develop rectal cancer than women.
  • Race: Statistically, Black individuals are more likely to develop rectal cancer. The reasons for this aren’t fully understood yet.
  • Family history: If you have a family member who has been diagnosed with rectal cancer, your chance of developing it is almost double.
  • Certain diseases and conditions: There are several health conditions that can increase your risk for rectal cancer, including inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis.
  • Smoking: Recent research suggests that people who smoke are more likely to die from rectal cancer than people who don’t.
  • Eating processed meat: People who eat a lot of red meat and processed meat have a higher risk of developing rectal cancer.
  • Obesity: People with obesity are more likely to have rectal cancer compared to people who are considered a healthy weight.

Experts recommend that all people have routine colorectal screenings beginning at age 45. People who have a higher risk of rectal cancer should undergo more frequent screenings. Find out more about general cancer screening guidelines recommended by healthcare providers.

What should I know about rectal cancer staging?

Rectal cancer is categorized into five different stages. Your diagnosis depends on how large the rectal cancer tumor is and whether or not it has spread:

  • Stage 0: Cancer cells have been found on the surface of the rectal lining.
  • Stage 1: The tumor has grown below the lining and possibly into the rectal wall.
  • Stage 2: The tumor has grown into the rectal wall and might extend into tissues around the rectum.
  • Stage 3: The tumor has invaded the lymph nodes next to the rectum and some tissues outside of the rectal wall.
  • Stage 4: The tumor has spread to distant lymph nodes or organs.

How does rectal cancer spread?

If you have Stage 4 metastatic rectal cancer, it means that the cancer has spread beyond the rectum into other areas of the body. While it’s possible for these cancer cells to travel anywhere in your body, they’re more likely to end up in the liver, lungs, brain or abdominal lining.

Diagnosis and Tests

How is rectal cancer diagnosed?

Most cases of rectal cancer are diagnosed during routine screenings. In some instances, your provider may suspect the disease based on your symptoms.

What tests will be done to diagnose rectal cancer?

If your healthcare provider thinks you could have rectal cancer, they may order some tests to confirm your diagnosis. These tests may include:

  • Colonoscopy: This test uses a long tube with a small camera to view the inside of your colon and rectum.
  • Biopsy: Your healthcare provider takes a small sample of suspicious tissue and sends it to a lab for analysis.
  • Computed tomography (CT) scan: This imaging test takes X-rays of your body, then stitches them together for a detailed view of your bones, organs and tissues.
  • Magnetic resonance imaging (MRI): Unlike X-rays, MRI uses radio waves and magnets to capture images inside your body.
  • PET scan (positron emission tomography): Before having a PET scan, your healthcare provider asks you to drink a special dye that contains radioactive tracers. (In some cases, the dye may be injected or inhaled.) The dye highlights areas of disease.

Management and Treatment

How is rectal cancer treated?

Rectal cancer treatment depends on several factors, including the location, size and stage of your tumor, as well as your overall health and personal preferences. Options include:

Surgery

One of the most common rectal cancer treatments, surgery removes cancer cells. There are a few different surgical options based on your specific needs:

  • Transanal endoscopic microsurgery (TEMS): During this procedure, your surgeon removes small cancers from the rectum using a special scope inserted through your anus. This treatment is recommended if your tumor is small, contained to one area and unlikely to spread.
  • Low anterior resection: Larger rectal cancers may require full or partial removal of the rectum. The anus is preserved so that waste can leave your body normally.
  • Abdominoperineal resection (APR): When cancer is located near the anus, it may not be possible to remove it without damaging the muscles that control your bowel movements. In this case, your surgeon may remove the anus, rectum and part of the colon. A colostomy is then performed so that waste can leave your body. (During a colostomy procedure, your surgeon creates an opening, or stoma, in your abdomen. The end of your colon is then attached to the opening and stitched into place. When waste leaves your body, it’s collected in a bag that’s connected to the stoma.)

Chemotherapy

Chemotherapy may be used before surgery to shrink a tumor, or after surgery to kill any remaining cancer cells.

Radiation therapy

Like chemotherapy, radiation therapy may be used before or after surgery. Radiation therapy uses strong energy beams to kill cancer cells or keep them from growing and dividing. It can be used in combination with chemotherapy.

Immunotherapy

Immunotherapy uses drugs to boost your immune system and teach your body how to attack cancer cells.

Targeted drug therapy

If you have advanced rectal cancer, your oncologist may recommend targeted drug therapy in combination with chemotherapy. These treatments target specific abnormalities in the cancer cells, causing them to die.

What are the complications of rectal cancer treatment?

Complications can vary depending on which type of rectal cancer treatment you receive. Additionally, every person’s experience may be different. Just because someone else had certain complications doesn’t mean that you will have them too. Tiredness, weight changes, nausea/vomiting and diarrhea are the most common side effects during most rectal cancer treatments.

Prevention

Can rectal cancer be prevented?

While you can’t prevent rectal cancer altogether, there are steps you can take to reduce your risk. For example:

  • Stay at a healthy weight.
  • Exercise regularly.
  • Eat a healthy, well-balanced diet.
  • Avoid drinking alcohol.
  • Don’t smoke.

Outlook / Prognosis

Can you survive rectal cancer?

Yes. When detected and treated early, rectal cancer can be successfully cured.

What’s the rectal cancer survival rate?

The overall five-year survival rate for rectal cancer is 63%. This means that people who have rectal cancer are about 63% as likely to be alive in five years as people who don’t have rectal cancer. The five-year survival rate for localized rectal cancer (that hasn’t spread to other areas of the body) is 91%. This means that people who have early stage rectal cancer are about 91% as likely to be alive in five years as people who don’t have rectal cancer.

Keep in mind that survival rates are estimates based on people who have had rectal cancer in the past. They can’t predict what will happen or how long you will live. To learn more about rectal cancer survival rates, talk with your healthcare provider.

Living With

When should I see my healthcare provider?

If you’re undergoing rectal cancer treatment, call your healthcare provider right away if you develop:

You know your body best, so trust your gut. If something doesn’t seem quite right, make an appointment with your healthcare provider. They can find ways to ease your symptoms and help you feel better.

What questions should I ask my healthcare provider?

If you’ve been diagnosed with rectal cancer, you’ll want to gather as much information as you can. Here are some questions to ask your healthcare provider:

  • What stage of rectal cancer do I have?
  • How far has the cancer spread?
  • What are my treatment options?
  • How will treatment affect my quality of life?
  • Will I be able to work during treatment?

A note from Cleveland Clinic

Being diagnosed with rectal cancer can be overwhelming. You may feel sad, scared, frustrated or angry. Ask your healthcare provider about resources that can help you navigate this difficult time. You may also want to consider joining a support group for people with rectal cancer. Knowledge is power. Having a full understanding of your diagnosis and treatment options can empower you and help you take back control of your health.

Last reviewed by a Cleveland Clinic medical professional on 08/27/2021.

References

  • American Cancer Society. Chemotherapy Side Effects. (https://www.cancer.org/treatment/treatments-and-side-effects/treatment-types/chemotherapy/chemotherapy-side-effects.html) Accessed 9/22/21.
  • American Cancer Society. Colorectal Cancer Stages. (https://www.cancer.org/cancer/colon-rectal-cancer/detection-diagnosis-staging/staged.html) Accessed 9/22/21.
  • American Society of Colon & Rectal Surgeons. Rectal Cancer. (https://fascrs.org/patients/diseases-and-conditions/a-z/rectal-cancer) Accessed 9/22/21.
  • American Society of Colon & Rectal Surgeons. Side Effects of Radiation Therapy. (https://www.cancer.net/navigating-cancer-care/how-cancer-treated/radiation-therapy/side-effects-radiation-therapy) Accessed 9/22/21.
  • Cancer.net. Colorectal Cancer: Risk Factors and Prevention. (https://www.cancer.net/cancer-types/colorectal-cancer/risk-factors-and-prevention) Accessed 9/22/21.
  • Merck Manuals. Rectum and Anus. (https://www.merckmanuals.com/home/digestive-disorders/biology-of-the-digestive-system/rectum-and-anus#:~:text=The%20rectum%20is%20a%20chamber,higher%20in%20the%20descending%20colon.) Accessed 9/22/21.
  • National Cancer Institute. Rectal Cancer Treatment. (https://www.cancer.gov/types/colorectal/patient/rectal-treatment-pdq) Accessed 9/22/21.
  • National Cancer Institute. Targeted Therapy to Treat Cancer. (https://www.cancer.gov/about-cancer/treatment/types/targeted-therapies) Accessed 9/22/21.

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