Inguinal hernia after radical prostatectomy for prostate cancer: results from a randomized setting and a nonrandomized setting.
BACKGROUND
Observational data indicate that retropubic radical prostatectomy (RRP) for prostate cancer (PCa) may induce inguinal hernia (IH) formation. Little is known about the influence of robot-assisted radical prostatectomy (RALP) on IH risk.


OBJECTIVE
To compare the incidence of IH after RRP and RALP to that of nonoperated patients with PCa and to a population control.


DESIGN, SETTING, AND PARTICIPANTS
We studied two groups. All 376 men included in the Scandinavian Prostate Cancer Group Study Number 4 constitute study group 1. Patients were randomly assigned RRP or watchful waiting (WW). The 1411 consecutive patients who underwent RRP or RALP at Karolinska University Hospital constitute study group 2. Men without PCa, matched for age and residence to each study group, constitute controls.


MEASUREMENTS
Postoperative IH incidence was detected through a validated questionnaire. The participation rates were 82.7% and 88.4% for study groups 1 and 2, respectively.


RESULTS AND LIMITATIONS
The Kaplan-Meier cumulative occurrence of IH development after 48 mo in study group 1 was 9.3%, 2.4%, and 0.9% for the RRP, the WW, and the control groups, respectively. There were statistically significant differences between the RRP group and the WW and control groups, but not between the last two. In study group 2 the cumulative risk of IH development at 48 mo was 12.2%, 5.8%, and 2.6% for the RRP, the RALP, and the control group, respectively. There were statistically significant differences between the RRP group and the RALP and control groups, but not between the last two.


CONCLUSIONS
RRP for PCa leads to an increased risk of IH development. RALP may lower the risk as compared to open surgery.