Better decision support tools needed for prostate cancer screening choice

September 28, 2009

This is Michael Pignone, M.D., M.P.H., from the University of North Carolina School of Medicine. Credit: UNC-Chapel Hill School of Medicine

Although screening for prostate cancer with the Prostate Specific Antigen (PSA) test in men ages 50-70 can detect the cancer before it becomes symptomatic, knowing whether screening is beneficial for these men is uncertain.

Recent trials have shown small or no reductions in prostate cancer mortality among those screened. The small potential for benefit must be balanced against the more common and immediate downsides of increasing the chance of prostate cancer diagnosis and treatment-related complications.

Developing more effective decision support tools may help men and their physicians discuss whether or not to undertake PSA screening.

Michael Pignone, M.D., M.P.H., authored an editorial in the Sept. 28 Archives of Internal Medicine about this issue. He reviewed two studies: one from the National Survey of Medical Decisions and a second study from Australia that modeled the potential effects of screening for use in discussions about screening.

Pignone is associate professor of medicine and chief of the division of general internal medicine in the UNC School of Medicine and a member of UNC Lineberger Comprehensive Cancer Center.

He explained, "To make a good decision about whether or not to be screened, patients need to know their chances of being helped by screening and their chances of being harmed."

"The National Survey of Medical Decisions suggests that patients are not being regularly informed about the advantages and disadvantages of screening. The downsides of screening were talked about in only 32 percent of the discussions. Half of the patients couldn't answer any of the knowledge questions correctly about screening risks.

The Australian study provides updated data for such conversations: screening increases the chance of being diagnosed with prostate cancer from 23 per 1000 to 53 per 1000 over 10 years. The number of men with treatment related impotence or incontinence would also be twice as common: about 26 per 1000 vs. 12 per 1000. The chance of death from prostate cancer would be reduced from 4 in 1000 to 3 in 1000."

"The next step is to study whether providing patients with such information and determining if it changes their knowledge and preferences about screening."

Source: University of North Carolina School of Medicine (news : web)