- Flexible sigmoidoscopy – A doctor uses a flexible, lighted tube (sigmoidoscope) to look at the interior walls of the rectum and the sigmoid (the left side of the colon).
- Colonoscopy – A doctor uses a flexible, lighted tube (colonoscope) to look at the interior walls of the rectum and the entire colon. Colonoscopies can be used as screening tests or as follow-up diagnostic tools when the results of another screening test are positive.
- Double-contrast barium enema (also referred to as a lower gastrointestinal or GI series) – This X-ray test highlights the inner part of the colon and rectum.
- Computed tomography (CT) colonography (or virtual colonoscopy) – This CT exam creates a 3D view of your colon and rectum.
Some tests predominantly find cancer:
- High-sensitivity fecal occult blood test (FOBT) – This test checks for hidden blood (small amounts of blood not detectable by visual inspection) in three consecutive stool samples.
- Fecal immunochemical test (FIT) – This test checks for occult (hidden) blood in the stool and is sometimes preferred over FOBT.
- Cologuard – This test checks for occult blood in the stool and altered DNA, which can cause colon cancer or polyps. For this at-home test you collect your stool, place it in the provided container and mail it to the lab.
- Shield by Guardant Health – This is an FDA-approved blood test to screen for colorectal cancer.
Regular screening for colorectal cancer using colonoscopy, sigmoidoscopy, stool or blood testing is generally recommended beginning at age 45 for people without specific risk factors. For those with a higher risk of colorectal cancer, screening should begin at a younger age and may need to take place more frequently. The decision to be screened after age 75 should be made on an individual basis, in consultation with your doctor.
Risk Factors for Colorectal Cancer
A risk factor is anything that increases your odds of developing colorectal cancer. It is important to be aware of your individual risk factors.
Most colon and rectal cancers develop due to aging, personal or family history, or lifestyle factors. Approximately 9 out of 10 people diagnosed with colorectal cancer are 50 or more years of age. In recent decades there has been an increase in cases in adults in their 20s, 30s and 40s as well.
Personal and family history risk factors include:
- Family history of colorectal cancer or adenomatous polyps (the most common type of colon polyp)
- Personal history of colorectal polyps or colorectal cancer
- Personal history of inflammatory bowel disease
- Personal or family history of inherited syndromes: the most common are familial adenomatous polyposis (FAP) and hereditary nonpolyposis colon cancer (also called Lynch syndrome)
Health and lifestyle risk factors include:
- Diabetes mellitus
- Heavy alcohol use
- High consumption of red meat
- High-fat diet low in fiber
- Obesity
- Sedentary lifestyles
- Smoking
One or more risk factors do not guarantee you will develop colorectal cancer. At the same time, few or no risk factors do not mean you will not develop colon or rectal cancer.
To discuss your specific risks and prevention tactics, schedule an appointment with one of our specialists.
International patients please learn more here or call 1.713.441.2340.
Colorectal Cancer Program Nationally Recognized for Quality, Outcomes
The Houston Methodist Colorectal Cancer Program is part of a renowned national quality consortium. We perform at the highest possible level for colon polyp detection and cancer prevention and treatment. Our surgeons use minimally invasive approaches in more than 95% of colorectal surgeries, resulting in faster recovery, less pain and fewer complications.
