Study suggests PSA screening reduces prostate cancer mortality in healthy men
MedWire News: Prostate-specific antigen (PSA) screening reduces the risk for prostate cancer-specific mortality (PCSM) compared with usual care in healthy men, suggest US study results.
In contrast, for men with at least one notable comorbidity, undergoing regular PSA screening does not reduce the risk for PCSM compared with remaining under usual care.
Indeed, among men with no or minimal comorbidity who receive PSA screening, the number needed to treat (NNT) to prevent one prostate cancer death after 10 years is only five, say Anthony D'Amico (Brigham and Women's Hospital, Boston, Massachusetts) and colleagues.
"These data serve to raise awareness that the selective use of PSA screening for men in good health appears to reduce the risk of PCSM with minimal overtreatment," they write in the Journal of Clinical Oncology.
The team investigated the effect of comorbidity status on PCSM in 73,378 screened and not-screened men from the Prostate, Lung, Colorectal, and Ovarian screening study.
Participants were randomly assigned to receive usual care, versus intervention, which consisted of annual PSA testing for 6 years, annual digital rectal examinations (DRE) for 4 years, and additional prostate biopsy for those with a PSA above 4 ng/ml and/or an abnormal DRE.
A total of 2271 men had no or minimal coborbidity - 1194 of whom underwent intervention - and 3974 men had at least one notable comorbidity (including cardiovascular disease or cancer) - 2196 of whom underwent intervention.
After 10 years of follow-up, 164 prostate cancer-specific deaths had occurred, with significantly fewer (n=22) occurring in the men with no or minimal comorbidities who received intervention compared with those who received usual care (n=38).
Despite this finding, intervention did not improve PCSM risk among men with at least one notable comorbidity compared with usual care, at 62 versus 42 deaths.
"Given the competing risks due to the significant comorbidity, the patient may die of another cause before any possible benefit of PSA testing, early prostate cancer detection, and curative treatment have the opportunity to manifest," note D'Amico and team.
The number of men needed to be screened and the NNT were calculated at 723 and 5, respectively. These contrast with the findings from the European Randomized Prostate Cancer Screening Study in which a NNT of 48 was calculated, comment the researchers.
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By Sarah Guy