Tumors of the small intestine, as in the case of duodenal tumors, are rare. Fatty tumors, connective tissue tumors, and blood vessel tumors are all benign in character. Some of them may take the form of polyps projecting into the intestinal lumen.

Tumors of the colon, on the other hand, are relatively common. In fact, cancer of the colon and rectum is now the most common type of internal cancer in the United States. Benign polyps are much more common in the large than in the small intestine. They may be very numerous. When multiple, the condition is referred to as polyposis — often, apparently, a congenital abnormality. These polyps are not often cancerous in the end.

In its basic sense, benign polyps may not pose instant danger. However, it must be removed immediately through colonscopy. This is because once these benign polyps become malignant, they become cancerous and, thus, develop colon cancer.

Basically, cancer of the colon and the rectum always arises from the epithelium lining of the intestine. The effects produced depend largely on its location.

As in the case of cancer elsewhere in the gastrointestinal tract, the chief symptoms are the passage of blood in the stools, anemia, obstruction, and perforation.

A suddenly developing obstruction may be the first symptom of cancer involving the colon anywhere between the cecum and the sigmoid, for in this region, where the bowel contents are liquid, a slowly developing obstruction will not become evident until the lumen is practically closed.

Cancer of the colon and the rectum causes earlier symptoms of partial obstruction, with constipation alternating with diarrhea, lower abdominal painful cramps, and distention.

Any person with a history of inexplicable change in bowel habit and the passage of blood in the stools should be studied carefully to rule out cancer of the large bowel.

The possibility that a rectal carcinoma or cancer of the colon exists is when the polyps are detectable but still asymptomatic and can still be operated. This condition is one important reason for the inclusion of a rectal examination as part of every routine physical examination.

Helpful additional symptoms, often present, are those of progressive weakness, anorexia, weight loss, anemia, and lower abdominal pain. The most important diagnostic procedures are the abdominal and rectal examinations, sigmoidoscopy, repeated examination of the stools for the presence of blood, determination of the blood-hemoglobin, concentration for anemia and, usually the most conclusive of all, the barium roentgenologic examination.

However, these symptoms are generally detectable mostly through physical examination. But for those who are not aware that they may be experiencing some extraordinary conditions that may suggest colon cancer, it is important to submit themselves for physical examination in order to detect the possibility of colon cancer.