Rectal Cancer

More than 40,000 people in the United States develop rectal cancer each year. When rectal cancer is found early, chances are good it can be treated successfully. Colon cancer and rectal cancer sometimes are grouped together and called colorectal cancer.

The rectum is a part of the digestive system, also called the gastrointestinal (GI) tract. The colon is the first 4 to 6 feet of the large intestine, also called the large bowel. The rectum is the last part of the large intestine, which ends in the anus.

Rectal cancer develops slowly and usually starts as polyps, which are overgrowths of tissue in the lining of the colon. Rectal cancer may develop within a polyp, but not all polyps contain cancer.

Types of Rectal Cancer

More than 95% of colorectal cancers are adenocarcinomas. Approximately 90% of colorectal adenocarcinomas began as adenomas, which are a type of polyp that may become cancer.

Rectal Cancer Risk Factors

Anything that increases your chance of getting rectal cancer is a risk factor. Rectal cancer risk factors include:

• Age: Rectal cancer is found most often in people over 50 years old.
• Family history of colorectal cancer or polyps
• Inherited disorders such as hereditary nonpolyposis colorectal cancer (HNPCC or Lynch) syndrome or familial adenomatous polyposis (FAP)
• Race or ethnic background: African Americans and Jews of Eastern European descent (Ashkenazi Jews) are at higher risk.
• Inflammatory bowel disease (Crohn’s disease or chronic ulcerative colitis)
• Colorectal cancer or polyps
• Obesity
• Lack of exercise
• Eating a lot of red meat, processed meats or meats cooked at very high heat
• Diabetes Type 2
• Cigarette smoking
• Drinking too much alcohol
  

Not everyone with risk factors gets rectal cancer. However, if you have risk factors, it’s a good idea to discuss them with your doctor. If you are concerned about inherited family syndromes that may cause rectal cancer, we offer advanced genetic testing to let you know your risk.

Rectal Cancer Prevention

Certain lifestyle choices may lower your chances of getting rectal cancer. Try to:

• Have regular screening tests
• Stay at a healthy weight
• Exercise regularly
• Eat a healthy diet with lots of fruits and vegetables
• Avoid cigarettes. 
• Drink alcohol only in moderation

Some people have an elevated risk of developing rectal cancer. Review the rectal cancer screening guidelines to see if you need to be tested.

Some cases of rectal cancer can be passed down from one generation to the next. Genetic counseling may be right for you. Learn more about the risk to you and your family on our genetic testing page.

Rectal cancer often does not have symptoms in the early stages. When it does have symptoms, they vary from person to person. Most rectal cancers begin as polyps, small non-cancerous growths on the rectum wall that can grow larger and become cancer.

Rectal cancer symptoms may include:

• Rectal bleeding
• Blood in the stool or toilet after a bowel movement
• Diarrhea or constipation that does not go away
• A change in size or shape of your stool
• Discomfort or urge to have a bowel movement when there is no need
• Abdominal pain or a cramping pain in your lower stomach
• Bloating or full feeling
• Change in appetite
• Weight loss without dieting
• Fatigue
  

These symptoms do not always mean you have rectal cancer. But if you notice one or more of these signs for more than two weeks, see your doctor.

Finding rectal cancer early greatly increases your chance for effective treatment. If diagnosed early, many rectal cancers can be treated successfully.

At MD Anderson, our specialists have remarkable expertise and skill in diagnosing rectal cancers. And they use the most advanced equipment and techniques to help them customize the best treatment for you. We are one of the leading centers in advanced rectal MRI evaluation and virtual colonoscopy (also called CT or computed tomography colonoscopy).

Rectal Cancer Diagnosis

If you have symptoms that may signal rectal cancer, your doctor will examine you and ask you questions about your health; your lifestyle, including smoking and drinking habits; and your family medical history.

One or more of the following tests may be used to find out if you have rectal cancer and if it has spread. These tests also may be used to find out if treatment is working.

Digital rectal exam: The doctor inserts a gloved finger into the rectum to feel for polyps or other problems.

Fecal occult blood test (FOBT): This take-home test looks for blood in stool. A stool sample is examined for traces of blood not visible to the naked eye.

Fecal immunochemical test (FIT): This take-home test detects blood proteins in stool.

Endoscopic tests, which may include:

Proctoscopy: A thin, tube-like instrument (proctoscope) is inserted into the rectum. This lets the doctor view the rectum. Suspicious tissue or polyps can be biopsied (removed) for examination.

Sigmoidoscopy: Flexible plastic tubing with a camera on the end (sigmoidoscope) is inserted into the rectum. This gives the doctor a view of the rectum and lower colon. Suspicious tissue or polyps can be biopsied (removed) for examination. The tumor can be marked to help the doctor do minimally invasive surgery. Also called flexible sigmoidoscopy or flex-sig.

Colonoscopy: A colonoscope is a longer version of a sigmoidoscope. Doctors use it to look at the entire colon.

Endoscopic ultrasound (EUS): An endoscope is inserted into the body. A probe at the end of the endoscope bounces high-energy sound waves (ultrasound) off internal organs to make a picture (sonogram). Also called endosonography.

Imaging tests, which may include:

• CT or CAT (computed tomography) scan
• MRI (magnetic resonance imaging) scan
• PET/CT (positron emission tomography) scan
• Virtual colonoscopy or CT (computed tomography) colonoscopy: A scope is not put into the rectum, and you do not have to be sedated.
• Double contrast barium enema (DCBE): Barium is a chemical that allows the bowel lining to show up on X-ray. A barium solution is given by enema. Then a series of X-rays are taken.
  

Blood test for carcinoembryonic antigen (CEA): This blood test looks for CEA, a tumor marker made by most rectal cancers. It also can be used to measure tumor growth or find out if cancer has come back after treatment.

Rectal Cancer Staging

If you are diagnosed with rectal cancer, your doctor will find the stage of the disease. Staging is a way of determining how much disease is in the body and where it has spread. This information helps the doctor plan the best way to treat the cancer. Once the staging classification is determined, it stays the same even if treatment works or the cancer spreads.

Rectal Cancer Stages

(source: National Cancer Institute)

Stage 0: Abnormal cells are found in the innermost lining of the rectum. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 also is called carcinoma in situ.

Stage 1: Cancer has formed and spread into the first (submucosa) or second (muscle) layers of the rectal wall. It has not spread outside of the rectum.

Stage 2: Cancer has spread outside of the rectal walls into the surrounding fat or nearby tissue. It has not gone into the lymph nodes. It is divided into stages IIA, IIB, or IIC depending on the extent of local tumor involvement.

Stage 3: Cancer has spread to nearby lymph nodes. It has not spread to other parts of the body. It is divided into stages IIIA, IIIB, or IIIC depending on the extent of local tumor involvement and the number of lymph nodes that contain cancer.

Stage 4: Cancer has spread to other parts of the body, such as the liver, lungs or ovaries. It is divided into stages IVA and IVB depending on the number of different other parts of the body to which the cancer has spread.

At MD Anderson, your rectal cancer treatment is customized by a team of experts with incredible expertise and experience. We work together to provide the most advanced, least invasive therapy, while focusing on your quality of life. Your treatment team may include:

• Oncologists
• Surgeons
• Radiation oncologists
• Gastroenterologists
• Genetics specialists
• Gynecologists
• Specially trained nurses, ostomy nurses, nutritionists and social workers
  

Our doctors have special expertise in treating hereditary types of rectal cancer, as well as rectal cancer that has metastasized (spread) to other parts of the body or has returned being treated. Advanced genetic testing allows us to personalize your rectal cancer treatment and determine if you or any of your family members may be at risk for other cancers.

Our Rectal Cancer Treatments

If you are diagnosed with rectal cancer, your doctor will discuss the best options to treat it. This depends on several factors, including:

• The stage of the cancer
• The location of the cancer in the rectum
• If rectal cancer has just been diagnosed or has come back
• If rectal cancer has spread to other parts of the body
• Your general health
  

One or more of the following therapies may be recommended to treat rectal cancer or help relieve symptoms.

Rectal Cancer Surgery

Surgery is the most common treatment for rectal cancer that has not spread to distant sites. Rectal cancer surgery is most successful when done by a specialist with a great deal of experience in the procedure. MD Anderson surgeons are among the most experienced in the nation.

Rectal cancer may be treated with surgery alone or surgery combined with radiation, chemotherapy and/or other treatments. Chemotherapy or radiation may be given:

• Before surgery to improve the effectiveness of surgery with less impact on your body. This is called neoadjuvant therapy.
• After surgery to help keep you cancer-free. This is called adjuvant therapy.
  

The type of surgical method used to treat rectal cancer depends on the stage and location of the tumor. Your doctor may recommend one of the following:

Polypectomy: Suspicious or cancerous polyps on the inside surface of the rectum usually can be removed during a colonoscopy. A colonoscope, which is a long tube with a camera in the end, is inserted into the rectum. The doctor guides it to the area needing treatment. A tiny, scissor-like tool or wire loop removes the polyp.

Local excision: If rectal cancer tumors are small and have not grown into the wall of the rectum, they sometimes may be removed through the anus.

Proctectomy (rectal resection): The area of the rectum where the cancer is located, along with some healthy surrounding tissue around the rectum, is removed. Nearby lymph nodes are removed (biopsied) and looked at under a microscope.

Depending on where the tumor is, the colon may be reconnected to the rectum or anus. This is called sphincter-preserving surgery. If the tumor is too low within the rectum or anus, a colostomy may be needed.

In a colostomy, a stoma (hole) is cut in the abdomen wall into the colon. Body waste goes through the stoma into colostomy, which is a plastic bag outside the body. Sometimes, a temporary ileostomy may be used to allow the reconnection of the bowel to heal after surgery.

Surgery may be done by:

• Traditional open surgery
• Minimally invasive surgery

Your doctor will decide which method is best for you.

During minimally invasive surgery, small cuts are made in the abdomen. A tiny camera and surgical instruments are inserted. The surgeon uses video imaging to perform the surgery just as would be done with open surgery. Minimally invasive surgery sometimes is done with the surgical robot (da Vinci®).

Minimally invasive surgeries for rectal cancer include endoscopic mucosal resection and endoluminal stent placement.

Pelvic exenteration: If rectal cancer has spread into other organs, such as the colon, bladder, prostate or female reproductive organs, those organs may be removed during surgery. Often a colostomy may be needed for elimination of bodily waste. Even with extensive resection, the expert surgeons at MD Anderson sometimes can perform sphincter- preserving surgery to avoid a colostomy.

Chemotherapy

MD Anderson offers the most up-to-date and effective chemotherapy options for rectal cancer.

Targeted Therapies

MD Anderson offers novel therapies for certain types of rectal cancer. These innovative new drugs stop the growth of cancer cells by interfering with certain proteins and receptors or blood vessels that supply the tumor with what it needs to grow, survive and spread.

Radiation Therapy

New radiation therapy techniques and expertise allow MD Anderson doctors to target rectal cancer more precisely, delivering the maximum amount of radiation to the tumor with the least damage to healthy cells.

MD Anderson provides the most advanced radiation treatments for rectal cancer, including:

• Brachytherapy: Tiny radioactive seeds are placed in the body close to the tumor
• 3D-conformal radiation therapy: Several radiation beams are given in the exact shape of the tumor
• Intensity-modulated radiotherapy (IMRT): Treatment is tailored to the specific shape of the tumor to reduce damage to normal tissue.

Proton Therapy

The Proton Therapy Center at MD Anderson is one of the world’s largest and most advanced centers. It’s the only proton therapy facility in the country located within a comprehensive cancer center. This means this cutting-edge therapy is backed by all the expertise and compassionate care for which MD Anderson is famous.

Proton therapy delivers high radiation doses directly into the tumor, sparing nearby healthy tissue and vital organs. For many patients, this results in better cancer control with fewer side effects.