PR examination and screening or diagnosis of prostate cancer

Digital rectal examination (DRE) should be offered to men with lower urinary tract symptoms or symptoms suggestive of metastatic disease (1).

DRE can be used to detect:

• the prostate for signs of prostate cancer - a hard gland, sometimes with palpable nodules
• benign enlargement - smooth, firm, enlarged gland (1)

Symmetric enlargement is a common finding in aging men (2). A gland which feels normal in DRE does not exclude a tumour (1)

The effectiveness of DRE in detecting prostate cancer is not well established

• estimated sensitivity is fairly poor (53% to 59%) while the specificity is better (83% to 94%)
• many early prostate cancers will not be detected by DRE (1)
• studies have shown that in patients who had a biopsy done based on DRE findings, 72% to 82% of will not have prostate cancer
• in addition, around quarter of patients who had prostate cancers detected with biopsy after abnormal DRE findings, prostate cancer was found in a different area than to the DRE findings (2).

DRE is not recommended as a screening test in asymptomatic men (1)

A single study with symptomatic men showed (3):

• sensitivity and specificity for DRE as a predictor of prostate cancer in symptomatic patients was 28.6 and 90.7%, respectively. The positive and negative predictive values were 42.3 and 84.2%, respectively.

Reference:

• 1. Prostate Cancer Risk Management Programme Information for primary care; PSA testing in asymptomatic men. Evidence document. NHS Cancer Screening Programmes, 2010
• 2. Wilbur J. Prostate cancer screening: the continuing controversy. Am Fam Physician. 2008;78(12):1377-84
• 3. Jones D et al. The diagnostic test accuracy of rectal examination for prostate cancer diagnosis in symptomatic patients: a systematic review.BMC Fam Pract. 2018 Jun 2;19(1):79