Introduction
According to the American Cancer Society (ACS), an estimated 106,100 people will be diagnosed with colon cancer in 2009. Unfortunately, this disease can be very deadly and colorectal cancer will take the lives of an estimated 49,920 deaths that same year. However, with an increase in awareness of the disease, and an emphasis on regular colon cancer screenings, the deaths from this specific form of cancer continue to decrease, according to the ACS.
Definition
According to the National Cancer Institute, colon cancer is defined as any cancer that forms in the tissues of the large intestine known as the colon. Most colon cancers originate from the fluid and mucus producing cells, making them adenocarcinomas. Colon cancer and rectal cancers are often lumped together into one definition (colorectal cancer), as each forms tend to metastasize (spread) into both tissues of the colon and rectum. Colon cancer can be found through three main screening methods.
Colonoscopy
One of the most common ways that colon cancer is found is through a colonoscopy. During a colonoscopy, a scope is inserted through the rectum to take a close look for bumps called polyps, on the colon walls. The scope consists of a long tube with a video camera attached to the end. This video camera broadcasts the images to a screen, allowing the doctor to view the image during the procedure. The same tube can be used to take a small tissue sample of any suspicious abnormalities. This is called a biopsy. The samples can then be sent to a lab to search for signs of cancer.
X-ray
X-rays are also a common tool used to help find colon cancer. In this procedure, an x-ray is combined with a barium enema. The barium enema inserts a special dye into your rectum and intestines. This coats the walls of the organs and creates a silhouette of your colon walls, which can easily be viewed on an x-ray. Any potential signs of cancer will show up as abnormal bumps on the colon walls.
CT Scan
With new advances in technology, a virtual colonoscopy can also be done. This involves the non-invasive use of a MRI or CT scans to produce a 2D or 3D image of the colon. If an abnormality is found, a traditional colonoscopy may still need to be performed to gain a sample tissue of the abnormality for a biopsy. A virtual colonoscopy may also miss abnormalities smaller than 5 millimeters, which a traditional colonoscopy would discover.
