Impact of Prostate Volume on Oncological and Functional Outcomes After Radical Prostatectomy: Robot-Assisted Laparoscopic Versus Open Retropubic

ABSTRACT

PURPOSE: We compared the impact of prostate volume on oncological and functional outcomes 2 years after robot-assisted laparoscopic prostatectomy (RALP) and open radical retropubic prostatectomy (ORP). MATERIALS AND METHODS: Between 2003 and 2010, 253 consecutive patients who had undergone prostatectomy by a single surgeon were serially followed over 2 years postoperatively. RALP was performed on 77 patients and ORP on 176. The patients were divided into two subgroups according to prostate volume as measured by transrectal ultrasound less than 40 g and 40 g or larger. Recoveries of potency and continence were checked serially by interview 1, 3, 6, 9, 12, and 24 months postoperatively. RESULTS: RALP was associated with less blood loss (ORP vs. RALP 910 mL vs. 640 mL, p<0.001) but a longer operation time (150 minutes vs. 220 minutes, p<0.001) than was ORP. No statistically significant differences were found between the two groups for oncological outcomes, such as positive surgical margin (40% vs. 39%, p=0.911) or biochemical recurrence (12% vs. 7%, p=0.155). The overall functional outcomes showed no statistically significant differences at 2 years of follow-up (continence 97% vs. 94%, p=0.103; potency 51% vs. 56%, p=0.614). In the results of an inter-subgroup analysis, potency recovery was more rapid in patients who underwent RALP in a small-volume prostate than in those who underwent ORP in a small-volume prostate (3 months 24% vs. 0%, p=0.005; 6 months 36% vs. 10%, p=0.024). However, patients who underwent RALP in a large-volume prostate were less likely to recover continence than were patients who underwent ORP in a large-volume prostate (97% vs. 88%, p=0.025). CONCLUSIONS: Patients can be expected to recover erectile function more quickly after RALP than after ORP, especially in cases of a small prostate volume.