Screening for Prostate Cancer: Digital rectal examination: outdated or still valuable?
Introduction and Objective: Digital rectal examination (DRE) is an important diagnostic tool of a urologist and it has been incorporated in screening programmes for prostate cancer (PC), such as the European Randomized Study of Screening for Prostate Cancer (ERSPC). In the Rotterdam section of this study, until 1997, a man with a PSA level â‰¥4.0 ng/ml or an abnormal result on DRE or TRUS (transrectal ultrasound) was offered a lateralised sextant prostate biopsy. After 1997 however, DRE and TRUS were discontinued as a biopsy indication and simultaneously the PSA threshold was lowered to 3.0 ng/ml. While TRUS clearly was not shown to be a valuable test for the early detection of PC, the value of DRE has been more controversial. In this study we summarise the evidence on the position of DRE in a PSA-based screening. Methods First, we assessed the variability in percentage of positive DRE between different physicians. Furthermore, we evaluated the additional effect of an abnormal DRE on the chance of a positive prostate biopsy result in men with an elevated PSA, the differences in characteristics between tumours detected in PSA range 2.0-4.0 ng/ml due to a positive DRE or due to a PSA cut-off, and the long-term effect of having an abnormal DRE. Finally, the effect of omitting DRE from the screening protocol was analysed. Results A positive result of a DRE is important subject to interobserver variability, varying from 4% to 28%. At very low PSA (<4.0 ng/ml), DRE has a poor PPV of approximately 10%. A suspicious DRE compared to normal findings, in addition to an elevated PSA, increased the chance of finding a positive biopsy at initial screening from 22.4% to 48.6%. This effect is independent of observer, but diminished with subsequent screening rounds. In the low PSA range of 2.0-4.0 ng/ml, DRE more selectively detects high-grade cancers when compared to biopsying all men, but still missed many of these. On long-term, however, an initially positive DRE with negative biopsy gives no worse outcomes regarding cancers detected later. Omitting DRE and TRUS, while lowering the PSA threshold to 3.0 ng/ml as a biopsy indication resulted in an overall decrease of 10% in the rate of biopsies, while the detection rate remained similar at 4.7%. On a relatively short-term follow-up, this neither resulted in an i! ncreased risk of interval cancers or PC detected in subsequent screening rounds. Conclusions At the first screening and when used in addition to an elevated PSA, DRE increases both the chance of finding PC and selectively detecting clinically significant disease. DRE could therefore be of use to optimise screening in subgroups of men. However, the predictive value of DRE is low in a screening setting, and therefore not suitable as a solitary screening tool in men with low PSA values.
|Keywords||PSA, digital rectal examination, prostate cancer, screening|
|Promotor||F.H. Schröder (Fritz)|
|Publisher||Erasmus University Rotterdam|
|Sponsor||Abbott, Astellas Pharma, Astra-Zeneca, BARD Brachytherapy, Beckman Coulter, Contactgroep Prostaatkanker, Dutch Cancer Society, GlaxoSmithKline, J. E. Jurriaanse stichting, MSD, Novartis, Olympus, SUWO, SWOP.|
Gosselaar, C.. (2008, November 5). Screening for Prostate Cancer: Digital rectal examination: outdated or still valuable?. Erasmus University Rotterdam. Retrieved from http://hdl.handle.net/1765/13729