Risk Factors & Symptoms
Screening & Diagnosis

Colon Cancer

Cancers of the colon and rectum, often collectively referred to as colorectal cancer, are life-threatening tumors that develop in the large intestine.

More than 80% of colorectal tumors develop from adenomatous polyps. These gland-like growths develop on the mucous membrane that lines the large intestine. They are usually either:

  • Tubular polyps, which are mushroom-like protrusions
  • Villous adenomas, which are flat and spreading and are more apt to become malignant (cancerous)
Polyps are very common, and most of them are benign. Their numbers increase with age. Polyps are found in about 25% of people by age 50, and 50% of people by age 75. Fewer than 1% of polyps under 1 centimeter (slightly less than half an inch) become cancerous. About 10% of larger polyps become cancerous within 10 years, and about 25% of these larger polyps become cancerous after 20 years.

The esophagus, stomach, and large and small intestine -- aided by the liver, gallbladder, and pancreas -- convert the nutritive components of food into energy and break down the non-nutritive components into waste to be excreted

Risk Factors

The lifetime risk of developing colon cancer in the United States is about 7%. Certain factors increase a person's risk of developing the disease.These include:
  • being over the age of 50
  • prescence of polyps of the colon
  • personal history of cancer.
  • Family hitory of colon cancer
  • cigarette smoking
  • diet
  • physical inactivity


It is common to have colon or rectal cancer without symptoms. Many patients are free of symptoms until their tumors are quite advanced. Symptoms associated with colorectal cancer may also be caused by other conditions. These symptoms include:
  • Changes in bowel movements, such as diarrhea or constipation, or change in consistency or size of stools
  • Feeling that the bowel has not emptied completely after a bowel movement
  • Abdominal discomfort such as gas, bloating, and cramps
  • Rectal bleeding or blood in stool
  • Pain when having a bowel movement
  • Unexplained weight loss
  • Unexplained iron-deficiency anemia (low red blood cell count)
  • Weakness and fatigue

Screening & Diagnosis


A colonoscopy is an examination of the entire length of the colon using a small camera attached to a flexible tube. Polyps usually can be removed during a colonoscopy and tested. Colonoscopies are designed to detect polyps and colon cancer in its earliest stages, when it’s most treatable.

Like most cancers, early detection is the best defense and can improve outcomes dramatically. That’s why the American Cancer Society recommends regular colonoscopies for all men and women, age 50 and older, whether or not you have any symptoms. Colon screenings are designed to detect polyps and colon cancer in its earliest stages, when it’s most treatable.

Colonoscopy performed every 10 years is recommended by all health organizations.

A colonoscopy is an outpatient procedure and offered at all five Alegent Creighton Health metro area hospitals. At Alegent Creighton Health, our state-of-the-art screening technology and diagnostic methods provide highly accurate results.

You'll need a doctor's referral for this test. If you don't have a primary care physician, we can help you find one near your home or where you work. You can even request an appointment online or call 1-800-ALEGENT (1-800-253-4368).

Flexible Sigmoidoscopy

Sigmoidoscopy is similar to colonoscopy but only examines the rectum and the lower two feet of the colon. (In contrast, colonoscopy allows the doctor to view the entire colon.) The procedure takes about 10 - 20 minutes, and sedation is optional. Preparation procedures are less demanding than those for colonoscopy.

Flexible sigmoidoscopy is recommended every 5-10 years, depending on the individual organization.

Double-Contrast Barium Enema (DCBE)

The double-contrast barium enema test uses an x-ray to image the entire large intestine. The test takes about 30 - 45 minutes, and sedation is not required. Preparations are similar to those for colonoscopy and sigmoidoscopy. For the test, barium sulfate is inserted into the rectum using a small, flexible tube. The colon is then pumped with air to help the barium spread through the colon. If polyps are detected in the x-ray, your doctor may recommend you have a colonoscopy for further investigation and removal.

CT Colonography (CTC), also called Virtual Colonoscopy

Virtual colonoscopy, also called CT colonoscopy, uses a computed tomography (CT) scan to take three-dimensional images of the colon. The test takes only 10 minutes to perform, and does not require sedation. (It does require the same preparations as standard colonoscopy to clean out the colon and bowel.) Air is pumped into the rectum through a small flexible tube. The patient is then slid into a CT scanner, which takes rapid images. Some recent studies indicate that CT colonoscopy has a high accuracy rate in detecting adenomas and cancers.

Guaiac-Based Fecal Occult Blood Test (FOBT) with High Test Sensitivity

A fecal occult blood test is a take-home test that uses stool samples to detect hidden (occult) blood in feces. It may detect small amounts of blood in your stool from polyps or a tumor, even when your stools appear normal. Your doctor will give you a kit with instructions on how to take stool samples and prepare them for the kit. Your doctor will also inform you about what medications and foods need to be avoided in the days prior to the test. The test kit and samples are sent to a laboratory and results usually come back in a few weeks. If blood is found in the stool samples, you will need to have a colonoscopy.

Guaiac-based fecal occult blood test (gFOBT) with high test sensitivity every year is recommended by all three organizations.

Fecal Immunochemical Test (FIT) with High Sensitivity

The fecal immunochemical test is a newer type of take-home test for hidden (occult) blood. The test is similar to the fecal occult blood test, but patients do not need to follow medication or dietary restrictions. As with the FOBT, a colonoscopy is recommended if blood is found in the stool.

Fecal immunochemical test (FIT) with high sensitivity every year is recommended by the ACS and ACG.

Stool DNA Test (SDNA)

Like the FIT and the FOBT, the stool DNA test is conducted at home and uses fecal samples. Instead of testing for the presence of blood, this test looks for abnormalities in genetic material that come from cancer or polyp cells. These genetic changes are found in genes such as APC, K-ras, and p53. If DNA mutations are found, a colonoscopy is needed. The stool DNA test is new and not yet widely available. Some insurance carriers may not cover its cost.

Stool DNA test (sDNA) is recommended by the ACG every three years.

Guidelines for Increased-Risk Groups

  • A known family history of inherited colorectal cancer syndromes such as familial adenomatous polyposis (FAP) or hereditary nonpolyposis colorectal cancer (HNPCC)
  • A strong family history of colorectal cancer or polyps, especially in first-degree relatives (parent, sibling, or child) who developed these conditions younger than age 60
  • A personal history of colorectal cancer or polyps
  • A personal history of chronic inflammatory bowel disease.

Patients in these high-risk groups who have changes that are identified as precancerous during colonoscopy will likely have their doctors discuss with them the possibility of a prophylactic or preventive colectomy (removal of the colon).


What now? It’s the most natural question to ask when you receive a cancer diagnosis. And it’s a question that’s hard to answer when dealing with the emotions and thoughts that inevitably overwhelm you after you’re given your test results. We understand this is a difficult time for you and your family. That’s why we offer the following treatment programs to all of our oncology patients in the Alegent Creighton Health system.

Cancer Medical Team

Your cancer medical team consists of a multi-disciplinary team of highly skilled professionals who care for every patient of the Alegent Creighton Health Cancer Center. Using state-of-the-art technology and treatment regimens, our doctors, nurses and other healthcare professionals treat more cancer patients than any other health care provider in the Nebraska.

Nurse Navigator Program

A Cancer Nurse Navigator is an oncology-certified nurse who is available to guide you and your family through the entire process of diagnosis and treatment at Alegent Creighton Health. The Nurse Navigator is a single point of contact who will be there with you every step of the way.

Cancer Support Services

The Alegent Creighton Health Cancer Support Team is comprised of a group of healthcare professionals who work together in a variety of ways to help the patient and family cope with cancer. Individual team members include Cancer Support Services Specialists, Medical Social Workers, Cancer Rehabilitation Specialist, Pastoral Services, Dietitians, Oncology Nurse Navigators, Hospice & Home Care Services, Inpatient Nursing Services, Radiation Oncology, and Volunteer Services.

Support groups:

  • Colon Cancer Support Group
  • Cancer Related Fatigue Support Group
  • Cancer Survivorship Program
  • Just for Kids - Cancer Support Group
  • Look Good, Feel Better
  • Lunch & Learn Cancer Support Group
  • Surviving Bereavement

Technologies & Therapies

  • TomoTherapy
    Alegent Creighton Health is the first in the Omaha area to offer the TomoTherapy® Hi·Art® (Highly Integrated Adaptive Radiotherapy) System. This all-in-one solution allows doctors to check the location of tumors before each treatment, then deliver painless, precise radiation therapy resulting in unmatched accuracy for cancer patients, especially those with breast, lung and prostate tumors.

  • Varian Trilogy
    The Varian Trilogy with RapidArc® radiotherapy technology is a revolutionary breakthrough in cancer treatment that delivers powerful tumor-destroying radiation with remarkable precision. 

Clinical Trials

We believe our patients should have access to the most advanced medicines or treatments available. Studies are available for cancer control, cancer prevention and cancer treatment. No patient is obligated to participate in cancer clinical trials and may withdraw at any time. However, those who do participate gain access to new medicines and other benefits, such as low or no-cost drugs and treatments.

Image Recovery Center

While cancer treatment outcomes are improving, hair loss, weight changes and skin changes leave you feeling like a shadow of your former self. At Alegent Creighton Health, we won’t let you face those challenges alone. The Image Recovery Center is an appearance-enhancement program designed to help you copy with some of the physical side effects of cancer treatment. 

Complementary Therapy

The purpose of integrative movement therapy is to "complement" conventional medicine by stimulating the body’s natural healing power. Healing the body, mind and spirit, Alegent Creighton Health offers massage therapy, Yoga, T’ai Chi meditation and other therapeutic exercises during cancer treatment.

Second Opinion Program

After you receive a cancer diagnosis, you will likely have many questions. It’s helpful to obtain as much information as possible to make informed decisions about your cancer management and treatment in order to feel confident about your care. Getting a second opinion from the Alegent Creighton Health Cancer Center can help with these concerns.

Cancer Inpatient Services

For more acute, palliative or end of life phases of cancer care, Alegent Creighton Health offers five locations throughout Omaha for inpatient cancer care services.


Colorectal cancer is among the most curable of cancers when it is caught in its early stages. The term "5-year survival" means that patients have lived at least 5 years since diagnosis. The 5-year survival rate for colon cancer diagnosed and treated at stage I is 93%. The rates fall to 72 - 85% for stage II, 44 - 83% for stage II, and 8% for stage IV. However, there are other factors, including the appearance of cancer cells under the microscope that can contribute to a patient's prognosis.


Support Groups

  • Breast Cancer Support Group
  • Cancer Related Fatigue Support Group
  • Cancer Survivorship Program
  • Just for Kids - Cancer Support Group
  • Look Good, Feel Better
  • Lunch & Learn Cancer Support Group
  • Surviving Bereavement
  • Conversations for the Cure
Learn more about our cancer support groups.