The research discovered that an increased body mass index (BMI) at the time of diagnosis was an independent risk factor for prostate cancer mortality.
Overweight and obese men (men with BMI ĄÝ25 kg/m2) at the time of diagnosis were nearly twice as likely to die from locally advanced prostate cancer as patients who had a normal BMI at diagnosis.
The survey conducted in 2007 states that of over 218,000 American men likely to be diagnosed with prostate cancer, 27,000 died from prostate cancer.
With obesity as identified as a risk factor for prostate cancer the impact of obesity on survival treatment is less understood. The treatments include the complete surgical removal of the prostate, external beam radiation, and hormonal therapy.
The study involved 788 patients with locally advanced prostate cancer and observed for over eight years to determine the independent relationship between BMI and prostate cancer mortality.
The researchers for the first time utilized the data from a large randomised prospective treatment study with long term follow-up to investigate this relationship.
According to the authors being overweight or obese at the time of diagnosis was a unique, independent risk factor for death from prostate cancer. Compared to men with normal BMI (BMI<25), men with BMI between 25 and 30 were more than 1.5 times more likely to die from their cancer.
Similarly, men with BMI ĄÝ30 were 1.6 times more likely to die from their disease compared to men with normal range BMI.
The study found that after five years the prostate cancer mortality rate for men with a normal BMI was less than seven percent compared to about 13 percent for men with BMI ĄÝ25.
"Further studies are warranted to evaluate the mechanisms for this increased cancer-specific mortality among overweight and obese men and to assess the impact of BMI on survival following other management strategies and in clinically localized disease. Whether weight loss after prostate cancer diagnosis alters disease course remains to be determined," said Dr. Jason Efstathiou from Massachusetts General Hospital in Boston.
The study was published in the December 15, 2007 issue of 'Cancer' journal of the American cancer Society.