Single PSA Screening Intervention Does Not Improve Prostate Cancer Mortality

Submitted by onc_editor on Wed, 03/07/2018 - 16:41

Prostate cancer mortality remains identical among men, regardless of whether or not they underwent single prostate-specific antigen (PSA) screening, according to results published in the JAMA (online: March 6, 2018; doi:10.1001/jama.2018.0154)

PSA screening remains controversial, as the potential mortality or quality-of-life benefits of detection in the disease’s early stages can be outweighed by harmful effects from overtreatment.

Richard M Martin, PhD, Bristol Medical School (England), and colleagues evaluated the effects of a single prostate-specific antigen (PSA) screening intervention and standard diagnostic pathway on prostate cancer-specific mortality in the largest ever prostate cancer screening trial.

The study included 419,582 men between ages 50-69 years and was conducted at 573 primary care practices across the United Kingdom. A total of 189,386 men (intervention group) were invited to have a one-off PSA test and compared with 219,439 men (control group) who were not invited for screening.

Researchers noted that 75,707 of the 189,386 men in the intervention group (40%) attended the PSA testing clinic and 67,313 (36%) underwent PSA testing. Of the 64,436 patients with a valid PSA test result, 6857 (11%) had a PSA level between 3 ng/mL and 19.9 ng/mL, of whom 5850 (85%) had a prostate biopsy.

After a median follow-up of 10 years, the number of men diagnosed with prostate cancer was higher in the intervention group (n = 8054; 4.3%) than in the control group (n = 7853; 3.6%). More prostate cancer tumors with a Gleason grade of 6 or lower were identified in the intervention group (n = 3263; 1.7%) than in the control group (n = 2440; 1.1%).

Additionally, researchers reported that 549 patients (0.30 per 1000 person-years) died of prostate cancer in the intervention group vs 647 patients (0.31 per 1000 person-years) in the control group (rate difference, −0.013 per 1000 person-years, showing the same percentage of men dying from prostate cancer in both the invention and control groups). In the analysis of all-cause mortality, there were 25,459 deaths in the intervention group vs 28,306 deaths in the control group (RR, 0.99; 95% CI, 0.94 to 1.03; P = .49).

Dr Martin and colleagues concluded that there is no significant difference in prostate cancer mortality after a median follow-up of 10 years with a single PSA screening intervention, but there was an increase in the detection of low-risk prostate cancer cases. “Although longer-term follow-up is under way, the findings do not support single PSA testing for population-based screening,” they noted.—Janelle Bradley