Avoiding Colon Cancer

People who smoke, drink alchohol daily, or have a family history of colon cancer are by far the most likely of all your patients to develop colon polyps that could turn cancerous. At slightly increased risk are those who eat lots of red meat.

These were among the many useful findings from a major new study at 13 Veterans Administration hospitals (JAMA.2003;290:2959-2967). The study involved 3121 asymptomatic patients 50 to 75 years of age who had not had any type of colonic examination for at least 10 years and agreed to have colonoscopies. Nearly all the subjects were men.

it turned out that 329 patients (10.5%) had at least one advanced neoplastic lesion of (less than or equal to) 10 mm. Consuming greater than one alcoholic drink a day more than doubled the risk of these dangerous growths, current smoking increased the risk by 85% and having at least one first-degree relative with colon cancer increased the risk by 66%. In contrast to earlier research, there was no risk associated with being overweight.

What factors are protective? The researchers, lead by David Lieberman, MD, chief of gastroenterology at the Oregon Health and Sciences University in Portland, reported that physical activity, occasional or daily use of aspirin, and high intake of fiber, calcium, total folate, vitamin D, and multivitamins were associated with reduced risk. While earlier investigations have shown no protective effect with fiber, this study found that those in the highest quintiles of wheat based cereal fiber intake had significantly less risk of advanced neoplasia.

In a secondary analysis, smoking was the only risk factor associated with both hyperplastic polyps and advanced neoplasia. "Smoking emerged as a stronger risk factor than... expected," Lieberman noted, "[and] vitamin D turned out to be a 'strong' protection against polyps. This supports an earlier report showing that vitamin D and calcium may work together to lower the cancer risk."

Mark Pochapin, MD, chief of GI endoscopy at new York Weill Cornell Medical Center in New York City and a noted expert in the field, praised the study as "large and well-designed." he was most surprised by the strong protection shown by vitamin D; in previous studies, the nutrient had only a modest effect. As for the high risk associated with alchohol, he noted that drinking "is hard on the GI tract, causing reflux, ulcers and other problems." Some studies show moderate wine drinking helps prevent cardiovascular disease, but Dr. Pochapin never recommends it. Nor would he recommend daily aspirin unless the patient is at risk for stroke, in which case aspirin could play a double preventive role.

Meanwhile, another new study found that the more aspirin consumed, the greater the protective effect against colorectal adenoma. Data gathered over eight years from 27,000 nurses showed that women who reported taking more than 14 regular aspirin tablets weekly had the lowest risk and women who never or rarely used aspirin had the highest risk.

- Larry Frederick

© 2003 Wayne Hollopeter, M.D. All Rights Reserved
This website hosted by Wild Web West. Contact: Webmaster