Colorectal Cancer

What is colorectal cancer?

The colon and rectum are part of the digestive system.  Colorectal cancer is cancer of the colon or the rectum.  Colorectal cancer occurs when abnormal cells grow out of control in the colon or rectum. 

What are risk factors for colorectal cancer?

A risk factor increases the chance of getting colorectal cancer.  Not all colorectal cancers have risk factors and not everyone with a risk factor develops colorectal cancer.  Following are risk factors for colorectal cancer.

• Age –  Most cases of colorectal cancer occur after the age of 50.
• Personal History – Having a personal history of colorectal cancer increases your risk for recurrence.
• Family history – Having a first-degree relative with colorectal cancer increases the risk for colorectal cancer. 
• Familial colorectal cancer syndromes – Familial adenomatous polyposis (disease where hundreds of polyps develop usually occurring between ages 5-40) and hereditary nonpolyposis colon cancer (develops at a young age, but with only a few polyps).  Both of these are genetic disorders.
• Chronic inflammatory bowel disease
• Diet
• Physical Inactivity
• Diabetes
• Obesity
• Alcohol
• Smoking
  

What are prevention strategies for colorectal cancer?

While not all colorectal cancers can be prevented, there are things a person can do to reduce their risk factors for colorectal cancer.

• Diet – A diet low in fat, high in fruits and vegetables, and high in fiber can reduce the risk of colorectal cancer.  Avoid or limit alcohol consumption to no more than one drink a day.
• Physical Activity – Having a physical activity routine can help maintain a normal body weight and lower the risk of colorectal cancer.
• Smoking – Avoiding smoking can reduce the risk of colorectal cancer.
• Screening – Follow recommended screening guidelines.  Finding polyps before they become cancerous, reduces the risk of colorectal cancer.

Is screening available?

There are several screening options available, including Fecal Occult Blood tests and colonoscopy.

Click here to learn more about colorectal cancer screening guidelines. (link to screening document)

What are the symptoms of colorectal cancer?

Often there are no symptoms in the early stages of colorectal cancer.  Most colorectal cancers begin as polyps, a small benign growth, which grow and become cancerous.  Symptoms can include:

• Rectal bleeding;
• Blood in or on the stool after a bowel movement;
• Stools that are narrower than usual;
• Abdominal cramping or pain in the lower area of the stomach;
• Discomfort or urge to have a bowel movement when there is no need;
• Long bout of diarrhea, constipation or feeling the bowel does not empty completely;
• Vomiting;
• Fatigue;
• Weight loss for no apparent reason; or
• Frequent gas pains

These symptoms can also be caused by other conditions.  It is important to talk with your healthcare provider if you are experiencing any of these symptoms.

How is colorectal cancer diagnosed?

If colorectal cancer is suspected, diagnostic tests will be performed.  Your doctor may use one or a combination of the following tests.

• History and physical examination – This is performed to assess risk factors, family history and gather information gathering on things such as weight, pain, symptoms, and medical condition.
• Fecal occult blood test – This checks the stool for blood.
• Digital rectal exam – The doctor, or nurse, inserts a lubricated and gloved finger into the rectum.
• Barium enema – Barium, a liquid compound, is inserted in to the rectum.  A series of x-rays are taken of the lower gastrointestinal tract.
• Sigmoidoscopy –A thin lighted tube, a sigmoidoscope, is inserted through the rectum.  This allows the doctor to look at the lower part of the colon, sigmoid colon, for polyps.
• Colonoscopy – Similar to the sigmoidoscope, a thin lighted tube, called a colonoscope, is inserted through the rectum and looks at the colon to check for polyps.
• Biopsy – This removes tissue to check for cancer and may be done during a sigmoidoscopy or colonoscopy.
  
  

Imaging tests may also be done.  These can include:

• Endorectal ultrasound – A transducer is inserted into the rectum to see how far the cancer may have penetrated or spread.
• Intraoperative ultrasound – This is used during surgery, once the abdomen is open.  It can help to detect if the cancer has spread to other organs such as the liver.
• Computed tomography (CT) scan – This is used in making an initial diagnosis and helpful in staging the cancer.
• Magnetic resonance imaging (MRI) – Like the CT scan, it is helpful with diagnosis and staging.
• Positron emission tomography (PET) scan – Radionuclide glucose is injected into the vein and the PET machine takes pictures of where the glucose is absorbed.  Malignant tumors show up brighter because they take up more glucose than normal cells.

What is staging?

Staging describes the extent of the cancer.  It determines if the cancer has spread and if so, what parts of the body are affected.  Staging a cancer is important to assist the doctor to determine the appropriate course of treatment and assess an accurate prognosis.

The most common staging system is the TNM.

• T – size of the tumor
• N – degree to which regional lymph nodes are involved
• M – the absence or presence of distant metastases

Once the TNM has been determined, then a stage of I, II, III or IV is assigned.

• Stage I – cancers are small and local and usually curable
• Stage II & III – typically these are locally advanced and could involve the lymph nodes
• Stage IV – cancer has metastasized and can be inoperable

What are treatment options?

There are three standard treatments for colorectal cancer. 

• Surgery – This is the most common form of treatment for colorectal cancer.  The doctor will resection, sew two ends of the colon together, after the tumor and necessary colon have been removed.  Sometimes it is necessary to perform a colostomy if a resection is not possible.  A stoma, or opening, is made outside of the body where waste can pass through.  A bag is placed around the stoma to collect the waste.  Sometimes a temporary colostomy is needed to allow the colon to heal.
•  Chemotherapy – This systemic drug is administered through the veins to kill cancer cells.

• Radiation therapy - This uses high energy rays to kill cancer cells.

Other treatment that may be used :

• Biological therapy – This form of treatment helps the body’s immune system attack and destroy cancer cells and may help the body recover from some of the side effects of treatment.
  

What clinical trials are available?

Clinical trials are studies that seek to find better ways to prevent, screen, diagnose and treat a disease such as cancer.  Clinical trials test new approaches to treatment, such as, new drugs, new approaches to surgery or radiation therapy, or a combination of treatments.

Learn more about clinical trials.

What questions should I ask my doctor?

It is often helpful to make a list of questions before an appointment.  This will help you to remember what the doctor says.  Patients and care givers can write notes or ask if they may use a tape recorder.  Sometimes it is helpful to have a family member or friend at the appointment to take notes, ask questions or just listen.  Below are a few suggested questions a patient may ask their doctor.

Will you please write down the type of cancer that I have?

What stage is my cancer and what does that mean?

What are my treatment options?

What treatment do you recommend and why?

What are the risks and benefits of each treatment?

What are possible side effects of treatment?

How will you help manage my side effects?

How will treatment affect my normal activities?

Are there specific things I must do to get ready for treatment?

Are there other things I can be doing to help with my treatment, such as diet and exercise?

What resources can I use to learn more about my cancer and help me deal with it?

Make an appointment

Resources

American Cancer Society – 1-800-ACS-2345

American Society of Colon and Rectal Surgeons

National Cancer Institute – 1-800-4CANCER