[Infected Pelvic Lymphocele after Robot-Assisted Radical Prostatectomy].

The aim of this study is to clarify the incidences of infected pelvic lymphocele (IPL) after robot-assisted radical prostatectomy (RARP). From 2016 to 2017, we evaluated 173 consecutive patients who underwent RARP. The transperitoneal approach was used for the RARPs. Limited lymph node dissection was performed in the pelvic lymphoceles region surrounding the obturator nerve. Patients with IPL were defined as those with infected pelvic lymphoceles classified as Clavien-Dindo (CD) classification system grade II or greater and a fever over 38 degrees Celsius. All other cases were defined as nonIPL. IPL was observed in 5 cases (2.9%) that were classified as CD grade II in 2 cases, IIIa in 2 cases, and IVa in 1 case. The most severe case (CD grade IVa) required temporary dialysis for acute renal failure during conservative treatment. While the dissected lymph nodes in the IPL group were sificantly greater than those in the nonlPL group (20.8 ± 7.1 vs 10.3 ± 6.0, P = 0.0298) and the preoperative prostate specific antigen in the IPL group was significantly higher than that in the nonIPL group (15.6 ± 21.7 ng/ml vs 9.0 ± 6.1 ng/ml, P = 0.0359), there were no significant differences in the other background factors between the two groups. In the multivariate analysis, the number of dissected lymph nodes was an independent predictive factor for IPL. While the incidences of IPL after RARP were low, the number of dissected lymph nodes was related to IPL.