Colon Cancer



What is Colon Cancer?

“Carcinoma of the colon and rectum causes more deaths than any other form of cancer.” There is a striking geographical distribution. For example, it occurs at the rate of 45 per 100,000 of the male population in the United States; 25 in Great Britain and six in Japan. The majority of growths affect the junction of the large bowel (called the sigmoid colon) with the rectum, the last short part of the intestinal system.

Colon Cancer Symptoms

The symptoms vary, depending on where the lesion is localized. However, as a general rule, it is suspected in any middle-aged or elderly person who complains of a change in bowel habits, an unexplained anemia, or dyspepsia of recent onset. It is associated with abdominal pain in some patients.



When the rectum is involved, there is an alteration in the person’s normal bowel habits in 80 per cent of cases. This is usually constipation alternating with diarrhea, and the passage of loose stools that may be tinged with blood and have a jellylike appearance. Often a mucus like material trickles into the anal area shortly after the person starts moving about in the morning. Often obvious blood puts in an appearance also. If the lesion is located higher up in the intestinal tract, in the sigmoid colon, symptoms may not be so obvious. In fact, the first indication may be the symptoms of a bowel obstruction.

Any alteration of bowel habits in older persons, any sign of blood in the bowel actions, requires urgent and immediate medical attention. Also, any sudden anemia (with weakness or pallor) must be checked at once. The majority of these cancers can be picked up on the first attendance at the doctor’s, for most are very near the anus.



If a direct relative (brother or sister, mother or father) has it, the risk reduces to one in eight. A small, noncancerous meaty growth called a polyp (much like a wart) is always the starting point, and these may produce minute amounts of blood.

Simple do-it-yourself home test kits are available to check for this so-called “occult (hidden) blood.” The “Ez-Detect” and the “Homoccult Test Kit” is easy to do, and a color change on test paper shows if blood is present and the need for an urgent visit to the doctor if it is a positive result. It indicates the need for a further examination, usually a colonoscope where the doctor inspects the whole large bowel under direct vision. Polyps may be removed (and examined by the pathology department). A correct diagnosis is quickly made.



Many older people now undergo a colonoscopic examination routinely every two years, especially if there is any adverse symptom or a family history of the disease. It is highly recommended for older people.