Prognostic Factors for the Success of Transurethral Microwave Thermotherapy of the Prostate

Abstract

Background: Transurethral microwave thermotherapy (TUMT) of the prostate is a minimally invasive treatment. Nevertheless, it is necessary to identify adequate candidates for a good treatment response. Aim: To determine and analyze prognostic factors for the success of TUMT. Material and Methods: A prospective study of 398 patients with benign prostatic hyperplasia (BPH) has been conducted. Initial patient related parameters were recorded before TUMT and 12 months after treatment. Statistical analysis of these parameters has been performed in order to identify prognostic factors for the success of TUMT. Prediction models of post-treatment parameters have been computed using multivariate analysis. Results: Based on clinical data, patients fell into three groups: 249 patients with good treatment response (62.56%), 104 patients with average response (26.13%) and 45 patients with no response or minor response (11.3%). The absence of a median prostatic lobe, a small or medium sized prostate, a moderate initial obstruction, minimal or moderate post-void residual volume and moderate initial symptoms, were significantly associated (p<0.001) with good treatment responses after TUMT. Positive predictive values for good or average TUMT response were high (90-98%) for the following predictors: absence of a median prostatic lobe, small or medium prostate size (<60g), light or moderate symptoms (IPSS<20), moderate obstruction (Q_max>5 ml), minimal or moderate PVR (<100 ml). Conclusion: Patients under 67 years, without median prostatic lobe, with medium-low outlet obstruction (Q_max above 7.8 ml), medium-low symptom scores (IPSS<21), post voiding residue under 91 ml, can be considered good candidates for TUMT.