Colon Cancer: Screening Is The Best Prevention

By Kaaren Valenta

Colorectal cancer is the second leading cause of cancer death in the United States. Every year about 135,000 Americans are diagnosed with cancers of the colon and rectum and 57,000 will die from this disease.

Ironically, colon cancer is easily prevented. Reliable screening methods currently exist to find and remove precancerous colon polyps before they develop into a serious health problem –– if only people would use them. Anyone who is age 50 or older and has not had a colon cancer screening should get one.

That was a message delivered at Danbury Hospital’s recent Medical Town Meeting, “Colon Cancer: Prevention, Detection, and Treatment,” by Dr Joseph Fiorito, chief of gastroenterology; Dr Marvin Prince, a gastroenterologist; and Dr Stuart Bussell, a colorectal surgeon. The three specialists discussed how colon cancer is diagnosed and treated.

“There is an equal risk of colon cancer for men and women,” Dr Fiorito said. “The causes aren’t known but it is believed that diet, geography, and perhaps genetics play a role. Fairfield County has one of the highest rates of colon cancer in not only Connecticut, but also the country and the world.

“Areas with diets that are high in saturated fats have high colon cancer rates,” he said. “In Japan, where the diet is mostly fish, there is very little colon cancer.

“It’s not just genetics,” he said. “We know from migration rates that families who move from countries like Japan to the United States develop increases in colon cancer rates in subsequent generations.”

As a person ages, the risk of colon cancer also increases, he said.

“Persons who are 50 years old have a six percent risk of getting cancer in their lifetime, but if there is one immediate relative who had colon cancer the risk is two to three times as great and if there are two relatives with colon cancer, the risk is 21 to 36 percent higher.”

Dr Fiorito said he advises patients with familial risk factors to get screened beginning at age 40 or even earlier.

“Colon cancer is a completely preventable disease,” he said. That’s because most cases of colon cancer start in a polyp, a precancerous growth that is easily detected and removed during a screening colonoscopy.”

Dr Fiorito said it takes about ten years for a polyp to develop into a cancer so there is a ten-year window of opportunity to prevent it. The most effective screening tool is the colonoscopy, a procedure in which a lighted tube is inserted into the colon allowing the doctor to see the entire stretch of the intestine.

“There are other tests such as the flexible sigmoidoscopy, which shows only 25 percent of the intestine, and the double-contrast barium enema, which is also not quite as good,” he said..

A new procedure, the virtual colonoscopy, “isn’t quite where we want it to be yet,” he said, and if a polyp is discovered during the procedure, a colonoscopy still would have to be done.

“The colonoscopy is the gold standard,” he said.

Dr Prince said that while many may have some trepidation against a colonoscopy, it is a safe test that does not hurt. Patients are under conscious sedation and do not feel anything painful, he said. Only rarely is there a complication, such as reaction to the sedation medication, bleeding, or other problem. Air is pumped into the colon during the screening, so there may be some cramping and flatulence afterwards.

“At the end of the procedure, you will be pretty awake and will be told about the screening,” he said.

Sometimes polyps will be found in the colon and removed, so patients are advised not to take aspirin, ibuprofen, or blood thinners for ten to 14 days before the screening to avoid the risk of bleeding.

Because the sedation used impairs fine motor control for 24 hours, patients need to have someone to drive them home after the procedure, which generally takes about 20 to 40 minutes, with a 15-minute recovery afterwards..

Polyps that are removed are sent to a lab for analysis, a procedure that takes four or five days. “It is rare for polyps that are one centimeter in size or less to be cancerous,” Dr Prince said.

According to the American Cancer Society (ACS), there would be a 90 percent reduction in colon cancer rates if colonoscopies were done periodically and polyps removed. Once a cancer develops, it grows in size, and can invade the wall of the colon. If it grows into blood vessels or lymph vessels, it can spread (metastasize) to the lymph nodes, liver, or lungs, among other areas.

If a polyp is too large to be removed, or cancer is found, then the patient is referred to a colorectal surgeon. Dr Bussell said the site of the polyp has been identified and “tattooed” during the colonoscopy, making it easier for the surgeon to find. Some operations can be done laparoscopically, making healing and recovery much quicker. When there is cancer, usually only a small part of the colon has to be removed, he said.

“Surgery is the only appropriate treatment for a cure,” he said. “Chemotherapy can be done afterwards, if it is appropriate.”

The symptoms of colon cancer are few –– possible bleeding, pain, or obstruction –– and by that time the risk is much higher. “Don’t wait for symptoms,” Dr Fiorito said. “The surgeon’s job is much more difficult and the outlook is not as good.”

According to the ACS, only 37 percent of colon cancers are detected in the earliest stages. Of those whose cancers are found at late stage, the five-year survival rate is less than ten percent.

In addition to a colonoscopy every five to ten years, patients also should have a digital exam and a stool sample test (fecal occult blood test) as part of their regular physical examinations.

While the cause of colon cancer is unknown, Dr Fiorito expressed the importance of a good diet, limiting fats and excess calories, increasing fiber intake, getting adequate amounts of vitamins A, C, D, and E, and taking calcium. Calcium is important, he said, because it seems to block the cells that turn into polyps. Supplements like selenium and folic acid have also been found to be helpful. Aspirin also reduces the incidence of cells becoming polyps, and people who are taking a daily aspirin for other health reasons are getting the added benefit of colon cancer prevention, he said. But he advised against starting an aspirin regime solely for this purpose.