Dr. John is a Laparoscopic Surgeon whose specialties include colorectal diseases. He has performed thousands of colonoscopy procedures over the last 25 years and gives us some insight into colon cancer prevention.
COLONOSCOPY SAVES LIVES!
Colon cancer is the third most common cancer and the second leading cause of cancer deaths. That’s the bad news. The good news is that today and for sometime now, medical science has had the knowledge and capability to essentially prevent colon cancer and with practically no discomfort. Then why is such a devastating disease still so prevalent? The answer is simply a combination of inadequate patient education and compliance.
Let’s first of all look at the cause. Colon cancer is quite common in the western world and relatively uncommon in parts of Africa and other nations where the diet consists of unprocessed foods and a large amount of roughage. Interestingly if one follows immigrants from these countries to the United States, colon cancer rates rise precipitously by the second generation, and approximate western rates by the third generation presumably because their diets have undergone westernization. That is the environmental story. The theory is that a diet containing processed foods and very little roughage leads to poor bowel habits, manifested by a relatively slow stool transit time resulting in carcinogens or cancer causing substances being in prolonged contact with the colonic lining. The converse of course is that a diet low in carcinogens and one that promotes a fast transit time will decrease the risk of colon cancer.
Unfortunately there is another side to the story and that is genetics. Some families carry genes which, notwithstanding diet, predispose the affected individuals to colon cancer, and there are also certain clinical conditions such as inflammatory bowel diseases and polyposis syndromes which also increase one’s risk.
Whatever the risk, we now know that the vast majority of colon cancer starts as a small noncancerous growth inside the colon called a polyp. Once formed, these benign polyps undergo increase in growth and subsequent histological change, resulting in a cancerous polyp, followed by cancerous spread within the bowel wall, ultimately metastasizing to lymph nodes and then to distant sites such as the liver and lung. It is this natural history of progression which gives us the opportunity to prevent colon cancer in virtually everyone.
The gold standard for screening, detecting and removing these polyps thereby preventing colon cancer is colonoscopy. In experienced hands, colonoscopy is a safe procedure performed by inserting a device called a colonoscope into the rectum and passing it up the entire colon. Sedation is given and so the patient has no knowledge or memory of the procedure. The tip of the colonoscope consists of a small camera that transmits a detailed video of the colon to a computer monitor where it is viewed real time by the colonoscopist. If the patient has had an adequate prep this allows a thorough examination of the colon, revealing any abnormalities. If polyps are encountered, they are removed by snares, passed through channels in the scope at the same time, thereby eliminating the possibility of malignant transformation.
Most recent data have resulted in recommendations that a first screening colonoscopy be performed somewhere between ages 45- 50 and every 3 years thereafter. Symptoms such as a change in bowel habits, bloody or black stool, weight loss, and abdominal or rectal pain also obviously necessitates colonoscopy at any age.
Colon cancer is the one cancer that can be almost entirely prevented. . As more and more people undergo colonoscopy with each passing year, the cases of colon cancer diagnosis continues to drop!! Don’t let myths and unwarranted fears prevent you from getting your colonoscopy examinations. Colonoscopy saves lives!