Colorectal cancer is a cancer that affects the colon and/or rectum. It is the third most common cancer worldwide, usually affecting men and women 50 years and older.
Common presenting symptoms include rectal bleeding, bloody stools, change in bowel habits and weight loss.
According to the American Cancer Society, it is estimated that 50,630 people in the U.S. will die of colorectal cancer in 2018. Due to its high prevalence and mortality rate, both American Gastroenterology Association and ACS have recommended that we begin screening average risk adults starting at the age of 50; those with a higher risk of developing colorectal cancer — having a family history of CRC and/or inflammatory bowel disease, for example — screening is recommended at an earlier age than 50. Due to a lack of awareness within communities, 1 in 3 Americans are not screened and may be at risk of developing colorectal cancer.
Colonoscopy is the primary procedure used for CRC screening. This test employs a colonoscope, a flexible tube that employs fiber-optic technology and a high-resolution video camera, which allows the physician to take pictures and videos of the large intestine. Furthermore, it provides the ability to remove polyps, acting as both a diagnostic and therapeutic modality. According to ACS, colonoscopy has the potential to prevent 65 percent of colorectal cancer, and it is important to understand that the sooner it is detected the better are the odds of beating it, as CRC is easily treatable if detected early in its progression.
How does colonoscopy prevent colorectal cancer? Well in order to answer this question, it is important to first understand how colorectal cancer develops. Initially, you first develop a precancerous polyp, an abnormal growth of tissue that protrudes from the inner mucosa lining of large bowel, that progresses to advanced adenoma and eventually adenocarcinoma (cancer); this may take 10-15 years to develop, but could be accelerated by genetic factors if present. It is estimated that more than 80 percent of colorectal cancers develop from these precancerous polyps. As such, regular screenings with colonoscopy can often prevent their development into cancer by identifying and removing them — early on.
The next question to address is what to expect during a colonoscopy? The answer to this question is subjective, but essentially 98 percent of patients report that the procedure is virtually painless. In fact, most fail to have any recollection of the procedure being done, considering that it is done while sedated and monitored throughout the entire process for safety and efficacy.
Is colonoscopy the only modality available to detect “precancerous” polyps? The answer is no. There are other procedures — stool tests, capsule endoscopy, CT colonography, barium enema — that can be done but only for diagnosis. In another word, if polyps are detected, those options do not provide the means to remove them and would require subsequent colonoscopy to be performed for therapeutic intervention. Therefore, it is highly recommended that you choose colonoscopy from the get-go in order to save yourself extra time and medical procedures.
Overall, colorectal cancer is preventable, treatable and beatable if detected early on with screening. Colonoscopy is the most effective screening modality for detecting and preventing early stages of colorectal cancer, but there are other options available if you are not comfortable with this procedure. Ultimately, any form of screening is better than no screening!
Mohamed Alsalahi serves as director of gastroenterology and endoscopy at Newark-Wayne Community Hospital.