INTRODUCTION: Controversy remains as to the value of digital rectal examination (DRE) for detecting prostate cancer in men presenting with lower urinary tract symptoms and low prostate-specific antigen (PSA) levels. The purposes of the present retrospective investigation were to: (1) evaluate the positive predictive value (PPV) of an abnormal DRE in patients with PSA < 3 ng/mL, (2) describe the stage and grade of the cancers detected, and (3) describe the treatment modalities used for patients at each clinical stage.
METHODS: A prospectively maintained prostate biopsy service database of consecutive men undergoing prostate biopsies from April 2004 to April 2006 was reviewed. Patients with PSA < 3 ng/mL and definitely abnormal DRE were divided into 3 groups according to PSA range. The relationship between abnormal DRE and positive prostate biopsy was determined. The International Prostate Symptom Score (IPSS), clinicopathologic features of prostate cancer, and the treatments used for each clinical stage were summarized.
RESULTS: From 1235 men who underwent prostate biopsies, 59 (4.6%) had PSA < 3 ng/mL and an abnormal DRE. Their mean age was 63.4 years. Fifteen of the 59 patients had true-positive DRE; 44 patients had false-positive DRE. The PPV of an abnormal DRE for detecting prostate cancer was 25.4%. The incidence of prostate cancer was 13.3%, 33%, and 53.3% in patients with abnormal DRE and PSA levels of 0.1-1.0 ng/mL, 1.1-2.0 ng/mL, and 2.1-2.9 ng/mL, respectively. Patients with significant LUTS (IPSS > 19) were likely to have false-positive DREs (P = .019). Patients with mild LUTS (IPSS < 7) and abnormal DREs tended to have positive prostate biopsies (P = .030). Modalities used to treat the 15 patients with cancer included active monitoring, brachytherapy, and external beam radiotherapy in 3 (20%), 5 (33.3%) and 4 (26.6%) patients, respectively. Hormonal deprivation was used for 1 patient; radical prostatectomy was used for 2 patients.
CONCLUSIONS: DRE has a significant role in detecting prostate cancer in men presenting with PSA < 3 ng/mL. The higher the PSA, the greater the possibility of detecting prostate cancer in this selective cohort.
KEYWORDS: Digital rectal examination; Low PSA; Prostate cancer diagnosis
CORRESPONDENCE: Michael Nomikos MD, FEBU, Consultant Urologist, Knossou 275, Heraklion, Crete, 71409,Greece ().
CITATION: Urotoday Int J. 2010 Jun;3(3).
doi:10.3834/uij.1944-5784.2010.06.07