Can we predict who will need lymphocele drainage following robot assisted laparoscopic prostatectomy (RALP)?

Pelvic lymph node dissection (PLND) can cause lymphoceles. Lymphocele formation following PLND can reach up to 60% and are symptomatic in 0.4 to 16% of patients. The aim of the study was to identify factors that are significantly associated with lymphocele drainage. We retrospectively analysed all men that underwent RALP between April 2010 and November 2018 from our prospectively collected IRB approved database. All patients who developed lymphoceles were grouped into two groups, the ones who were drained and those not drained. Chi-square test was used to perform univariate analysis for categorical variables and student's t test for continuous variables. Odds ratio was calculated using logistic multiple regression analysis. A P value of less than 0.05 was considered significant. The size of the lymphocele, the number of nodes retrieved, and BMI were significant factors that led to the drainage of lymphocele. The patients with lymphoceles larger than 10 cm had an odds ratio of 47.5 and those between 5 and 10 had an odds ratio of 10.7. The odds ratio of drainage in patients with BMI above 30 was 2.1. The odds of drainage were 8.8 when more than 10 nodes were taken. After PLND ultrasound could be effective in early identification of patients who could potentially need drainage. Early elective drainage should be offered to patients who have more than 10 lymph nodes removed with a lymphocele size more than 10 cm in size and BMI above 30.