Pelvic lymph node dissection is associated with symptomatic venous thromboembolism risk during laparoscopic radical prostatectomy

Purpose Venous thromboembolism is a potentially catastrophic complication of radical prostatectomy. It is unknown whether pelvic lymph node dissection is related to the development of venous thromboembolism. We hypothesized that omitting pelvic lymph node dissection may be associated with a decreased incidence of venous thromboembolism. Materials and Methods The records of 773 consecutive patients who underwent laparoscopic radical prostatectomy by a single surgeon from 2001 to 2009 were reviewed for postoperative venous thromboembolism. All patients underwent laparoscopic radical prostatectomy with or without pelvic lymph node dissection and had at least 3 months of followup. Generally only patients at increased risk for lymph node metastasis received pelvic lymph node dissection. Diagnostic studies were not routinely performed but were initiated for clinical symptoms of venous thromboembolism. Separately a meta-analysis of radical prostatectomy studies with or without pelvic lymph node dissection was performed to evaluate associations with venous thromboembolism. Results Of the 773 patients 468 (60.8%) underwent laparoscopic radical prostatectomy plus pelvic lymph node dissection, 302 (39.2%) underwent laparoscopic radical prostatectomy without pelvic lymph node dissection, and 3 were missing preoperative data and were excluded from study. Patients in the laparoscopic radical prostatectomy plus pelvic lymph node dissection and laparoscopic radical prostatectomy only groups were similar in age, body mass index and prostate volume, although they differed in pathological characteristics and operative time. Venous thromboembolism occurred in 7 of 468 (1.5%) patients who underwent laparoscopic radical prostatectomy plus pelvic lymph node dissection and in 0 of 302 (0%) who underwent laparoscopic radical prostatectomy only (p = 0.047). Patients in whom venous thromboembolism developed had greater body mass index (30.8 vs 27.1 kg/m², p = 0.015) than those in whom venous thromboembolism did not develop. No patient had a symptomatic lymphocele. Meta-analysis of the literature demonstrated a significant association between venous thromboembolism and radical prostatectomy plus pelvic lymph node dissection compared to radical prostatectomy only (RR 2.15, CI 1.144.04, p = 0.018). Conclusions Pelvic lymph node dissection during radical prostatectomy increases the risk of venous thromboembolism. In carefully selected low risk patients omitting pelvic lymph node dissection may decrease the incidence of venous thromboembolism.