Bladder neck-sparing retropubic radical prostatectomy: assessing risk factors for detection of positive surgical margins

Background. Bladder neck preservation during retropubic radical prostatectomy (rRP) promotes a protective effect on urinary continence compared to standard rRP. Aim. To assessment of possible predictors for positive surgical margin (PSM) recognition is an important step. Materials and methods. 136 patients with localized prostate cancer (PCa) were studied in the study. Group 1, 90 patients (retrospective assessment), underwent standard rRP, group 2, 46 patients (prospective assessment), underwent rRP modified by bladder neck preservation with a part of the proximal prostatic urethra. The clinical and pathological stages of PCa were assessed; the groups were compared to the parameter PSM. Statistical analysis was performed using nonparametric statistical methods. Results. Both groups were comparable in age and baseline total prostate specific antigen (PSA) but differed in prostate volume and Gleason score. Also, there were differences in clinical and pathological stages of PCa. PSM-patients had more aggressive PCa according to the International Society of Urological Pathology (ISUP) and TNM classifications and had higher progression risk prognosis stages. In PSM-patients, correlations were determined between prostate volume and baseline Gleason index (r = 0.338; p >0.05); baseline total PSA and Gleason score before (r = 0.529; p >0.05) and after (r = 0.310; p >0.05) rRP, respectively. Nevertheless, the incidence of PSM among all subjects was 6.6 % of cases, while in groups 1 and 2 was 7.8 and 4.3 % of cases, respectively. In this way, surgical techniques that maximize bladder neck preservation with a part of proximal prostatic urethra have no significant effect on PSM. Ranges of total PSA, clinical stage of PCa, Gleason score and progression risk stages (prognostic group for PCa) were determined as predictors of PSM. Their use will make it possible to establish patient selection criteria for bladder neck preservation with proximal prostatic urethra during rRP. Conclusion. The identified predictors will allow determining during clinical staging minimal risks of detecting PSM. The rRP modified by bladder neck preservation with part of the proximal prostatic urethra does not increase the incidence of PSM compared to the standard rRP. The feasibility of this technique should be related to total PSA, clinical stage of PCa, Gleason score, and the progression risk stage.