NEW YORK (Reuters Health) - Obese patients are more likely to have a recurrence of colon cancer than their normal-weight counterparts and face an increased risk of dying from the disease, a new study shows.While it’s not clear that losing weight would improve their prognosis, Dr. James J. Dignam of the University of Chicago and colleagues note, healthy lifestyle changes would probably have other beneficial effects for obese colon cancer patients.

There is strong evidence that being obese, defined as having a body mass index (BMI) of 30 or greater, both increases the likelihood of developing colon cancer and worsens prognosis for individuals diagnosed with the disease, Dignam and his team report in the Journal of the National Cancer Institute.

To better understand the relationship between a patient’s BMI and the outcome of chemotherapy for colon cancer, Dignam and his team looked at 4,288 colon cancer patients participating in two large nationwide clinical trials.

The patients underwent surgery following a diagnosis of Dukes B or C colon cancer and all of the patients were randomly assigned to a chemotherapy regimen.

Subjects with a BMI of 35 or greater (defined as very obese) had a 38-percent risk of a tumour recurrence compared with normal weight individuals (those with a BMI of 18.5 to 24.9), the researchers found.

The very obese were also 28 percent more likely to die during the 11.2-year follow-up period.