MP45-18 IS RETZIUS-SPARING ROBOT-ASSISTED RADICAL PROSTATECTOMY THE MORE ANATOMICAL APPROACH? – COMPARISON WITH CONVENTIONAL ROBOTIC PROSTATECTOMY

INTRODUCTION AND OBJECTIVES: Recent studies have demonstrated associations among the ABO blood group, risk, and prognosis in various diseases. However, to date, few studies have investigated the prognostic significance of the ABO blood group in prostate cancer. The aim of this study was to investigate the association of the ABO blood group with biochemical recurrence (BCR) after radical prostatectomy (RP). METHODS: We reviewed 719 patients who underwent RP for clinical T1e3N0M0 prostate cancer at our institution between 2000 and 2010. Patients who had neoadjuvant and/or adjuvant therapy were excluded from this study. As a result, a total of 592 patients were included for analysis in the present study. The associations among the ABO blood group, clinicopathologic factors, and BCR were analyzed using univariate and multivariate analyses. RESULTS: With a mean follow-up period of 67.3 months, 183 patients (30.9%) experienced BCR, with a 5-year BCR-free rate of 66.1%. Among the clinicopathologic characteristics, only surgical margin status was observed to significantly differ between patients with different ABO blood groups (A vs. B, P 1⁄4 0.005; AB vs. B, P 1⁄4 0.007). In univariate analyses, a higher serum prostate-specific antigen (PSA) level at diagnosis, extracapsular extension, a positive surgical margin, seminal vesicle invasion, lymphovascular invasion, and a higher Gleason score (GS 8) in the RP specimen were significantly associated with BCR. Although not a significant factor in univariate analysis (P 1⁄4 0.131), the ABO blood group, in addition to the serum PSA level, extracapuslar extension, positive surgical margin, seminal vesicle invasion, and Gleason score, was an independent predictor of BCR in multivariate analysis. Hazard ratio and 95% confidence intervals for BCR according to the ABO blood group were shown in the Figure. Blood type O patients demonstrated a significantly lower risk of BCR than type A patients (HR, 0.624; 95%CI, 0.432e8211;0.901; P 1⁄4 0.012). CONCLUSIONS: The ABO blood group was significantly associated with BCR in prostate cancer patients who underwent RP. In particular, blood type O is significantly associated with a decreased risk of BCR after RP. Further studies are needed to clarify the nature of this association.