Overweight, obese young men at increased risk for pancreatic cancer later in life

Young overweight or obese men who had ever smoked were at an increased risk for pancreatic cancer and a younger age of disease onset, according to researchers from M.D. Anderson Cancer Center in Houston.

“The stronger association of excess body weight at earlier adulthood with risk of pancreatic cancer suggests that weight control at younger age should be a primary preventive strategy to reduce the risk of pancreatic cancer,” Donghui Li, PhD, professor in the department of Gastrointestinal Medical Oncology at M.D. Anderson Cancer Center, told Endocrine Today.

The researchers assessed the associations between lifetime BMI and risk for pancreatic cancer, age at onset of disease and overall survival among 841 patients with pancreatic adenocarcinoma and 754 healthy controls matched by age, sex and race.

Patients who were overweight between age 14 and 39 (OR=1.67) or obese between age 20 and 49 (OR=2.58) were at increased risk for pancreatic cancer — independent of diabetes status. An increased association was found in men (OR=1.80) aged 14 to 59 vs. women (OR=1.32) and in “ever smokers” (OR=1.75) vs. “never smokers” (OR=1.46).

In addition, the population attributable risk for pancreatic cancer was 10.3% among those aged 14 to 59 who never smoked compared with 21.3% for ever smokers. Data further indicated that patients who were overweight or obese when aged 20 to 49 had a two- to six-year earlier onset of pancreatic cancer. The median age of onset was 64 years for patients with normal weight, 61 years for overweight patients (P =.02) and 59 years for obese patients (P >.001).

Patients who were overweight (P=.04) or obese (P >.001) when aged 30 to 79 or in the year prior to study recruitment had a reduced overall survival for pancreatic cancer regardless of disease stage and tumor resection status compared with controls.

“The finding on obesity and poor survival may have implications for the design and conduct of future clinical trials of pancreatic cancer,” said Li.

“This study by Li et al represents an incremental advance in the understanding of clinical factors contributing to pancreatic cancer development and progression,” Robert R. McWilliams, MD, and Gloria M. Peterson, MD, both of the Mayo Clinic in Rochester, Minn., wrote in an accompanying editorial.

“The biological bases for how overweight and obesity contribute to younger age of diagnosis, increased risk for pancreatic cancer and poorer survival in pancreatic cancer require further investigation,” they wrote. “Understanding these associations will provide much needed clues for targeting potential preventive and therapeutic strategies for this extremely aggressive and resistant type of cancer.” – by Jennifer Southall

Li D. JAMA. 2009;301:2553-2562.