Cancer of the colon is a major health problem in the United States ranking as one of the leading forms of cancer along with lung cancer and breast cancer. Colon cancer, however, is also one of the most curable forms of cancer when detected early. More than 90% of patients can be cured if colon cancer is detected in the early stages.
Colon disease begins in the cells that line the colon. There now is strong medical evidence that some abnormal genes colon polyps and cancer can be passed from parent to child. The genes within each cell are the hereditary structures that tell the cell what it should do. It is becoming increasingly more clear that certain genes control the growth of the cells on the lining of the colon. When these controlling genes are absent there is a tendency to grow polyps. The cells in the polyp eventually become uncontrolled and turn into a cancer. Colon cancer can also develop from other conditions, such as ulcerative colitis, a chronic inflammation in the colon.
A polyp is a growth that can occur in the colon and other organs. These growths, or fleshy tumors, are shaped like a mushroom or a dome-like button, and occur on the inside lining of the colon. They may be as small as a tiny pea or larger than a plum. It is important to note that while colon polyps start out as benign tumors, some polyps, in time, can become malignant. In fact, the larger the polyp, the more likely it is to contain cancer cells. In most cases, it is an adenoma polyp that develops into colon cancer.
Risk Factors for Developing Colon Polyps and Colon Cancer:
- Having a family history of polyps, cancer, or specifically colon cancer
- Living in a Western civilization and eating Westernized food in your diet
- Being over 40 years of age
- Having a history of breast cancer
- Having ulcerative colitis
An individual whose immediate family has colon cancer has an increased chance of also developing colon cancer or polyps. In addition, certain unusual conditions, such as hereditary polyposis, lead to colon cancer 100% of the time. Also, persons living and eating in Western societies are exposed to certain factors that are detrimental to the bowel. Medicine is just beginning to learn more about these factors. Additionally, females who have had genital or breast cancer are also at an increased risk of developing colon cancer. Finally, those with ulcerative colitis, after a long period of time, can also lead to colon malignancy.
As noted above, heredity is probably the most important factor in determining your risk of colon polyps and colon cancer. The absence of a controlling gene within a cell is most likely a necessary event.
There are other factors based on diet and environmental surroundings that are known to affect the risk of colon polyps and colon cancer. Rural residents in Africa and India rarely develop colon polyps or cancer. Their diets are high in unprocessed grains (bran) and low in meat. Diets like these, high in bran and roughage, produce bulky stools with a lower bacteria count. It is also known that animal fat in meat, when broken down by the body’s intestinal juices, may change into certain compounds called carcinogens. These compounds have caused colon cancer in laboratory animals. When residents in developing countries eat a Westernized diet of meat, low roughage and refined grains, over time they develop the same incidence of colon polyps and colon cancer as people living in the Western world. So diet probably plays an important role in causing colon cancer.
Enough is now known about polyps that physicians generally place patients into one of three categories. In each of these, the end result is an adenoma type polyp:
- The Ordinary Polyp – Most sporadic polyps occur between the ages of 40 and 60. There may be only one or two present and they may take ten years or more to develop into a cancer. There is a hereditary link.
- Familial Polyposis – This is a true hereditary condition in which the entire colon contains thousands of polyps. They begin at a very early age even under ten years old. And virtually every patient will eventually develop colon cancer. The only known preventative treatment is removal of the colon. Fortunately, this condition is not common.
- Lynch Disorder – This hereditary condition is more common than familial polyposis and less so than the ordinary polyp. With this disorder, there is a strong tendency for adenoma type polyps to develop in blood relatives; sisters, brothers, aunts, uncles, and children. More polyps are seen and at an earlier age. Polyps and even cancer can occur in the patients 30’s or even as early as their 20’s. In some families there is an increased incidence of breast, ovarian, and other cancers so a family history of this type warrants very close surveillance of all direct blood relatives.
The key to early detection of colon polyps and colon cancer is in the prevention and willingness of each person to seek medical attention from a physician. The physician will perform the following:
- Medical history – The patient’s medical history will identify risk factors for colon polyps and colon cancer.
- Stool exams to detect occult (hidden) blood – Colon cancers and large polyps release minute quantities of blood; therefore, examination of the stool for occult blood is an important exam.
- Sigmoidoscopy – A visual exam of the rectum and lower colon using a lighted, rigid or flexible tube or endoscope, allows the direct detection of colon tumors.
- Colonoscopy – This procedure examines the entire 5-6 foot long colon. Physicians perform it when any of the previous three detection methods suggest a problem. The exam is usually done under sedation. The colonoscopy is the definitive test as colon polyps can be discovered and removed at the same time. Click here to view a short, informational video about the procedure.
- Barium Enema – This x-ray exam is an older, and at times still useful, exam. Barium flows into the colon and x-rays are taken to outline the shadows of polyps and cancer. Polyps cannot be removed by this technique.
- Future tests – It is possible that a blood genetic test may become available to identify those individuals who are genetically more likely to develop colon polyps and cancer.
Removal of colon polyps reduces the risk of subsequent development into colon cancer. Polyps are usually removed using a colonoscope which allows the physician to visualize the inside of the colon. Biopsy equipment and snares (wire loops) are passed through the endoscope and, with electrical heat (electrocautery), remove polyps and small tumors. This procedure is performed in an outpatient setting under sedation.
Cancer of the colon is a serious but readily detected malignancy. Early detection promises a particularly high chance of survival. Most colon cancers start as polyps, which can usually be removed through a colonoscopy exam. With the medicine of today, there is much that can be done to prevent and cure colon cancer. The essential preventative step involves action by the patient.