Colon cancer race disparities puzzling

BIRMINGHAM, Ala., Nov. 30 (UPI) -- Body-mass index and existing medical conditions do not explain the decreased cancer survival among blacks compared to whites, U.S. researchers said.

University of Alabama at Birmingham researchers say that for many cancers, including colon cancer, African-Americans have lower survival rates than whites; possible reasons behind this disparity -- including genetic variation, tumor characteristics, access to healthcare and other factors -- are being examined extensively.

Lead author Upender Manne said there was a belief that racial disparity in survival following surgery for colon cancer was related to a high BMI and co-morbidity.

The researchers analyzed data from 496 patients who underwent surgery for colon cancer at University of Alabama at Birmingham Hospital from 1981-2002.

The study, published online in the journal Cancer, found African-Americans were 34 percent more likely to have died by the end of the study than Caucasians. Among patients with advanced stages of cancer, being underweight increased the risk of death by 87 percent. Being overweight or obese was protective in patients with Stage IV cancer and decreased the risk of death by 42 percent.

"That was the surprising finding for us -- that a high BMI was actually protective in patients with advanced-stage disease," Manne said in a statement.