Bowel Cancer Symptoms

The colon and rectum form the large intestine, the last one to one and a half meters of the gut, starting just inside the anus. Cancer of this area is responsible for more cancer deaths than other forms of cancer. Colorectal cancer is more common in men, and more than half develop in the last 10 cm of the gut, so it can be felt by a doctor doing a finger examination through the anus. A large cancer can also be felt as a hard lump in the abdomen, particularly in thin patients. Other patients with suspicious symptoms will need a colonoscopy and/or barium enema to confirm the diagnosis.

Patients who have a bad family history of bowel cancer, or symptoms that are less definitely suspicious, can have a sample of their feces tested for blood. Three samples are usually necessary over several days, and certain foods such as red meat, cauliflower, broccoli, turnips, bananas and radishes must be avoided before the test. A negative test does not positively exclude the presence of cancer, but lessens its likelihood. A positive test is an indication to investigate further. Some doctors now advocate a routine, regular feces blood testing for all men over 40.

The most common complication of this cancer is obstruction, when the cancer grows to a size where the feces cannot pass, and the intestine ceases to function. Another complication that can occur is a hole developing in the gut through or beside the cancer. This allows feces to leak into the abdomen, which leads to peritonitis and a critical illness.

There are no specific blood tests that will detect this type of cancer, but blood tests may show anemia caused by the constant slow leaking of blood from the cancer into the bowel.

The only curative treatment is major surgery to remove the cancer, the bowel for some distance above and below the cancer, and the surrounding lymph nodes. This is one of the most major operations routinely undertaken, and up to 5% of patients may die during or immediately after the operation. Without the operation, death from the cancer is inevitable.

If the cancer has not spread away from the large intestine, two out of three patients will survive for five years. If the cancer has spread, the survival rate drops steadily, depending on the degree of spread.

After the operation, regular examinations of the colon are required to detect at the earliest possible stage any recurrence of the cancer, or the development of a new bowel cancer (a phenomenon that is quite common in these patients).