Lymphoceles after pelvic lymph node dissection during robot-assisted radical prostatectomy.

Background: Lymphoceles, lymph fluid-filled collections within the body lacking epithelial lining, are a common complication after pelvic lymph node dissection (PLND) during robot-assisted radical prostatectomy (RARP). In this study, we investigate the incidence of imaging confirmed symptomatic lymphoceles (SLC) in a centralized high-volume operating centre and assess predictive factors and treatment. Methods: We retrospectively analysed the incidence, risk factors and treatment of a consecutive series of patients who underwent PLND during RARP between September 2018 and January 2021 in a specialised operation clinic. We compared baseline patients' characteristics and pathological data between men who developed an SLC and those who did not. A multivariable model for the occurrence of an SLC was created using predetermined, clinically relevant variables to investigate predictive factors. Results: We analysed the records of 404 patients. The median follow-up length was 29 months. A total of 30 (7.4%) patients with an SLC were identified. The median time until SLC presentation was 12 weeks [interquartile range (IQR), 4-31 weeks], one-third of SLCs presented after 180 days. Percutaneous drainage was performed in 17 patients (57%). On multivariable analysis, only body mass index (BMI) significantly increased the odds of an SLC [per 5 odds ratio (OR) =1.7; 95% confidence interval (CI): 1.0-3.0, P=0.04]. Conclusions: SLCs present significant consequences, as more than half of patients with an SLC were treated with percutaneous drainage. Many patients presented later than the centralized surgeons' postoperative follow-up, a drawback of centralized care. An increased BMI was a significant predictor for SLC.