Obesity, overweight at diagnosis ups B-cell lymphoma prognosis

(HealthDay) -- For U.S. veterans with diffuse large B-cell lymphoma (DLBCL), being overweight or obese at time of diagnosis correlates with improved survival, according to a study published online May 29 in the Journal of Clinical Oncology.

To investigate the association between body mass index (BMI) at diagnosis and overall survival, Kenneth R. Carson, M.D., from the St. Louis Veterans Affairs Medical Center, and colleagues conducted a retrospective cohort study involving 2,534 U.S. veterans diagnosed with DLBCL from 1998 to 2008.

The researchers found that the mean age at diagnosis was 68 years, and 64 percent of patients were overweight or obese. Compared with other BMI groups, obese patients were significantly younger, had significantly fewer B symptoms, and showed a trend toward lower-stage disease. Compared with normal-weight patients, Cox analysis showed decreased mortality for overweight and obese patients (hazard ratios, 0.73 and 0.68, respectively). Treatment during the rituximab era attenuated the mortality risk but did not impact the association between BMI and survival. One year before diagnosis, disease-related weight loss occurred in 29 percent of patients with weight data, but Cox analysis based on BMI one year before diagnosis showed a persistent association between overweight/obesity and reduced mortality risk.

"Being overweight or obese at the time of DLBCL diagnosis is associated with improved overall survival," the authors write. "Understanding the mechanisms responsible for this association will require further study."

One author disclosed a financial relationship with Genentech.