Obesity And Overweight Linked To Higher Prostate Cancer Mortality

In 2007, over 218,000 American men are expected to be diagnosed with prostate cancer and over 27,000 will die from the disease. While obesity has been identified as a risk factor for more clinically aggressive prostate cancer, the impact of obesity on survival following treatment is less understood. These treatments may include the complete surgical removal of the prostate, external beam radiation, and hormonal therapy.

Dr. Efstathiou and co-investigators reported on 788 patients with locally advanced prostate cancer followed for over 8 years to examine any independent relationship between BMI and prostate cancer-specific mortality. The study is the first to use data from a large randomized prospective treatment study with long-term follow-up to investigate this relationship.

The authors found that 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 ¡Ý30 were 1.6 times more likely to die from their disease compared to men with normal range BMI. 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 ¡Ý25.

Dr. Efstathiou and his co-authors conclude that their data support population-based studies that report similar associations between obesity and disease-related mortality. "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," conclude the authors.

Journal Article: "Obesity and Mortality In Men With Locally Advanced Prostate Cancer: Analysis of RTOG 85-31," Jason A. Efstathiou, Kyounghwa Bae, William U. Shipley, Gerald E. Hanks, Miljenko V. Pilepich, Howard M. Sandler, Matthew R. Smith, Cancer; Published Online: November 12, 2007 (DOI: 10.1002/cncr. 23093); Print Issue Date: December 15, 2007.