Significance of histological prostatitis in patients with urinary retention and underlying benign prostatic hyperplasia or adenocarcinoma of the prostate.

OBJECTIVE: To compare the clinical features of patients having urinary retention and benign prostatic hyperplasia (BPH) with those having adenocarcinoma of the prostate (ACP) and to evaluate the significance of histological prostatitis. PATIENTS AND METHODS: The clinical data and histopathology reports of patients with retention admitted to Tygerberg Hospital between September 1998 and June 2007 were evaluated. Statistical analysis was performed with Student's t-test, Mann-Whitney test and Fisher's exact test where appropriate and P < 0.05 was considered to indicate statistical significance. RESULTS: Prostatic histology was available in 405 patients, 204 with BPH and 201 with ACP. Comparing those with BPH and those with ACP showed statistically significant differences in mean age (69.5 vs 71.9 years), serum prostate-specific antigen (PSA) level (18.6 vs 899.5 ng/mL) and histological prostatitis (48 vs 25%) but not duration of catheterization, prostate volume or urinary tract infection (UTI). Comparing those with BPH only and those with BPH plus prostatitis showed significant differences in mean age (71.9 vs 67.1 year) and PSA level (14.6 vs 22.8 ng/mL) but not prostate volume, UTI or duration of catheterization. Comparing those with ACP only and those with ACP plus prostatitis showed significant differences in stage T4 cancer (68.1 vs 35.4%) and PSA level (1123.4 vs 232.4 ng/mL) but not age, prostate volume, UTI or duration of catheterization. CONCLUSIONS: Histological prostatitis was almost twice as common in patients with urinary retention associated with underlying BPH than in patients with ACP, but there was no significant difference in the duration of catheterization, prostatic volume or presence of UTI, suggesting that histological prostatitis more often contributes to the development of retention in patients with underlying BPH than in those with ACP. In patients with BPH, histological prostatitis was associated with urinary retention at a significantly younger age and with higher serum PSA levels. In patients with ACP, histological prostatitis was associated with urinary retention at an earlier stage of cancer.