Objective: In this study, the clinical usefulness of transition zone (TZ) volume (TZV) measured by transrectal ultrasonography (TRUS) was investigated as a new parameter for the preoperative prediction of the treatment efficacy of transurethral resection of the prostate (TURP).
Methods: Fifty-six men with symptomatic benign prostatic hyperplasia (BPH; age 68.6 +/- 9.7 years) underwent TURP and were evaluated based on ordinary BPH parameters such as the international prostatic symptom score (I-PSS), quality of life (QOL) score, peak urine flow and entire prostate volume (PV), as well as the new TZV parameters and calculation of the TZ index. Relative risks were adjusted simultaneously for potentially confounding variables by multiple logistic regression analysis after adjustment for age, QOL, I-PSS, Qmax and residual urine.
Results: The adjusted relative risk for TURP at a TZ index of 0.1 increased to 4.5 (95% confidence interval 2.3-8.78). In general, poor responses were observed in patients with less symptomatic scores or lower values prior to operation, but there was a weak correlation between treatment outcome and preoperative scores or values of ordinary parameters. The volume parameters of BPH and PV did not predict treatment efficacy preoperatively, but TZV and the TZ index correlated with the treatment efficacy of TURP.
Conclusion: TZV and the TZ index seem to be useful new parameters in preoperative decision-making with regard to TURP.