Duke oncologist Michael Harrison, MD, answers questions about the link between prostate cancer and obesity and screening for prostate cancer.

Is there a connection between obesity and prostate cancer?

Michael Harrison, MDA Duke study showed that obesity, which affects one in three men in the United States, is associated with prostate cancer spreading and prostate cancer death among men starting hormonal therapy for recurrences after surgery.

Previous studies from Duke have shown that obese men are more likely to have cancer come back after surgery, but this is the first study to show obesity is associated with worse outcomes after hormonal therapy.

How do you screen for prostate cancer?

By measuring the amount of prostate specific antigen (PSA) in a man's bloodstream, we can discover prostate cancer at earlier stages -- giving men a better chance for survival.

The test is not perfect. Some studies show that it misses up to 15 percent of cancer cases, while flagging some cancers so small and slow-growing that they pose no threat.

Still, the PSA test remains the best clinically available tool for predicting prostate cancer.

PSA screening is especially important for men with a family history of prostate cancer and for African-American men, who have a 60 percent higher incidence of the disease than whites.