Objective: To evaluate the outcomes based on gland size between robotically assisted radical prostatectomy (RALP) and open RP (RRP), as larger prostates might increase the difficulty of RP.
Patients and methods: We reviewed 660 patients who had RALP and 340 who had RRP from May 2003 to August 2006; the patients were divided into two groups, with a prostate of >75 and <or=75 g. The clinical characteristics, surgical approach, perioperative and postoperative outcomes were evaluated.
Results: Patients with large prostates were significantly older (P < 0.001), but had a lower pathological stage (RALP, P = 0.046, and RRP, P = 0.008) than patients with small glands, regardless of technique. There was no difference in length of stay or transfusion rates between the groups. A large prostate increased the operative duration of RALP (P < 0.001) but not of RRP. For both RALP and RRP, positive margin rates were lower with larger glands (RALP, P = 0.014; RRP, P = 0.033). Overall, the positive margin rates were lower with RALP (9.9% and 19.0%) than RRP (18.5% and 35.5%) among patients with larger or smaller (P < 0.001) glands, respectively.
Conclusions: Prostates of >or=75 g had fewer positive margins than smaller glands, regardless of surgical technique. There was also a significant decrease in positive margin rate in among prostates of >75 g in favour of RALP. Thus, RALP appears to be comparable with RRP for patients with large glands, and might reduce the positive margin rate.