Guest Author - Dr. Denise Howard
Colon cancer is a malignancy of the large intestine or colon and rectal cancer occurs in the rectum, which is the straight portion of the distal colon that leads to the anus. It regulates defecation. The term Colorectal refers to both areas. Colorectal cancer is the second most common cause of cancer deaths in the U.S. and the second most commonly diagnosed cancer in women worldwide. This is a potentially beatable cancer because of the knowledge of its development and the availability of effective screening tests.
Colorectal cancer occurs in the large intestine and the rectum. The digestive system consists of many parts. The digestive process starts in the mouth and stomach where enzymes break down the food into smaller particles. The small intestines are then responsible for the absorption of the nutrients. This is a complex process that involves the exchange of electrolytes and fluid.
Once the absorption of nutrients has taken place in the small intestine the remaining substance passes into the colon. This material goes through the cecum to the ascending colon then to the transverse colon and down through the descending colon into the sigmoid. From the sigmoid it travels into the rectum where it will wait until it can be evacuated through the anus. This passage allows for the finally absorption of electrolytes and water before the waste product is expelled from the body. Cancer can occur at any of these points.
The vast majority of colorectal cancers arise from adenomas. Most of these adenomas are polyps but not all. Approximately 2/3 of polyps are adenomatous with the potential to develop cancer while the other 1/3 are hyperplastic and donít develop into a malignancy. The adenomatous polyps typically grow from small to large and then transition to dysplasia, a precancerous state. The transition from dysplasia to cancer can take at least 10 years thus providing a large window of opportunity to remove the precancerous lesions.
Preventative care medicine recommends screening in those at risk. People over the age of 50 and those with a family history of colorectal cancer are at risk. The screening is designed to detect signs of an early cancer allowing for early treatment and removal of precancerous lesions before they have an opportunity to develop into cancer. These screening tests will be discussed in other articles.
I hope this article has provided you with information that will help you make wise choices, so you may:
Live healthy, live well and live long!