The quality of evidence is downgraded by inconsistency (unexplained variability in results).
The use of PSA cannot be suggested for screening prostate cancer.The recommendation attaches a relatively high value on avoiding adverse consequences of overdiagnosis and overtreatment.
A Cochrane review included 5 studies with a total of 341 342 subjects. All involved PSA testing, with or without digital rectal examination (DRE), though the interval and threshold for further evaluation varied across trials. The age of participants ranged from 50 to 80 years and duration of follow up from 7 to 20 years.
Meta-analysis of the five included studies indicated no statistically significant difference in prostate cancer-specific mortality between men randomised to the screening and control groups (RR 1.00, 95% CI 0.86 to 1.17). The two studies with low risk of bias - The European Randomized Study of Screening for Prostate Cancer (ERSPC) and the US Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial - provided contradicting results. The ERSPC study reported a significant reduction in prostate cancer-specific mortality (RR 0.84, 95% CI 0.73 to 0.95), whilst the PLCO study concluded no significant benefit (RR 1.15, 95% CI 0.86 to 1.54). The ERSPC was the only study that reported a significant reduction in prostate cancer-specific mortality, in a pre-specified subgroup of men aged 55 to 69 years of age. Sensitivity analysis for overall risk of bias indicated no significant difference in prostate cancer-specific mortality when referring to the meta analysis of only the ERSPC and PLCO trial data (RR 0.96, 95% CI 0.70 to 1.30). Subgroup analyses indicated that prostate cancer-specific mortality was not affected by the age at which participants were screened.
Meta-analysis of four studies investigating all-cause mortality did not determine any significant differences between men randomised to screening or control (RR 1.00, 95% CI 0.96 to 1.03). A diagnosis of prostate cancer was significantly greater in men randomised to screening compared to those randomised to control (RR 1.30, 95% CI 1.02 to 1.65). Localised prostate cancer was more commonly diagnosed in men randomised to screening (RR 1.79, 95% CI 1.19 to 2.70), whilst the proportion of men diagnosed with advanced prostate cancer was significantly lower in the screening group compared to the men serving as controls (RR 0.80, 95% CI 0.73 to 0.87).
Screening resulted in a range of harms that can be considered minor to major in severity and duration. Common minor harms from screening include bleeding, bruising and short-term anxiety. Common major harms include overdiagnosis and overtreatment, including infection, blood loss requiring transfusion, pneumonia, erectile dysfunction, and incontinence. Harms of screening included false-positive results for the PSA test and overdiagnosis (up to 50% in the ERSPC study). Adverse events associated with transrectal ultrasound (TRUS)-guided biopsies included infection, bleeding and pain. No deaths were attributed to any biopsy procedure. None of the studies provided detailed assessment of the effect of screening on quality of life or provided a comprehensive assessment of resource utilization associated with screening (although preliminary analyses were reported).
| Outcome | Relative effect (95% CI) | Assumed risk - No screening | Corresponding risk - Screening (95% CI) | Participants (studies) |
|---|---|---|---|---|
| All-cause mortality | RR 1 (0.96 to 1.03) | 21 per 100 | 21 per 100 (20 to 22) | 294856 (4 studies) |
| Prostate cancer-specific mortality | RR 1 (0.86 to 1.17) | 7 per 1000 | 7 per 1000 (6 to 8) | 341342 (5 studies) |
| Prostate cancer diagnosis | RR 1.3 (1.02 to 1.65) | 68 per 1000 | 88 per 1000 (69 to 112) | 294856 (4 studies) |
| Tumour stage (localised T1-T2, N0, M0) | RR 1.79 (1.19 to 2.7) | 6 per 100 | 10 per 100 (7 to 15) | 247954 (3 studies) |
| Tumour stage (advanced T3-4, N1, M1) | RR 0.8 (0.73 to 0.87) | 11 per 1000 | 9 per 1000 (8 to 9) | 247954 (3 studies) |