Colorectal Polyps and Cancer
What Are the Symptoms of Colorectal Cancer?
Unfortunately, colorectal cancer may strike without symptoms. For this reason, it is very important to talk to your doctor about whether you are at risk for colorectal cancer and should be screened.
In addition to getting a medical history and physical exam, there are a number of tests your doctor can perform to help detect colorectal cancer and polyps early. Tests to help detect colorectal polyps and cancer include:
- Sigmoidoscopy. This is a procedure used to examine the rectum and very last part of the colon. This test can detect polyps, cancer, and other abnormalities in the sigmoid colon and rectum. During this exam, a biopsy (tissue sample) may also be removed and sent for testing.
- Colonoscopy. A colonoscopy examines the entire colon and rectum. During this procedure, polyps can be removed and sent for testing.
- Colon X-rays. Also known as a double-contrast barium enema or lower GI series, this test provides an outline of the lining to detect abnormalities in the colon and rectum.
- CT colonography. This is a special X-ray test (also referred to as a virtual colonoscopy) done of the entire colon using a CT (computed tomography) scanner. This test takes less time and is less invasive than other tests. However, if a polyp is detected, a standard colonoscopy needs to be performed.
The earliest sign of colon cancer may be bleeding. Often tumors bleed only small amounts intermittently, and evidence of the blood is found only during chemical testing of the stool. This is called occult bleeding, meaning it is not always visible to the naked eye. When tumors have grown to a large size they may cause a change in the frequency or the caliber of the stool.
Symptoms of colorectal cancer include:
- A persistent change in bowel habits (such as constipation or diarrhea)
- Blood on or in the stool
- Abdominal discomfort
- Unexplained weight loss
What Happens If a Colorectal Polyp Is Found?
If colorectal polyps are found, they should be removed and sent to a laboratory for microscopic analysis. Once the microscopic type of polyp is determined, the follow-up interval for the next colonoscopy can be made.