Clinical Significance of Postoperative Lymphoceles Following Pelvic Lymph Node Dissection in Prostate Cancer Disease

Background and Aims: Pelvic lymph node dissection (pLND) in patients undergoing radical retropubic prostatectomy (rRPE) is often associated with postoperative lymphocele formation. This can lead to consecutive complications such as abscesses and thrombosis. The aim of this study was to evaluate the possible risk of complications due to the lymph node dissection and to identify risk factors being associated with symptomatic lymphoceles.

Methods: Between 02/2002 and 12/2003 all 504 patients who underwent pLND and rRPE were investigated on the 7^th postoperative day by pelvic and lower abdominal ultrasound. Volumes of lymphoceles were determined. Complications related to pLND were described and evaluated statistically to explore the role of possible risk factors.

Results: 66 patients (13%) (mean age 63, range 48-75 years) developed a lymphocele. There was no statistically relevant association between size of lymphoceles and age of patients, pre-surgical PSA, T-stage, prostate volume and the number of lymph nodes being removed, the body mass index and duration of surgical procedures. The size of lymphoceles was in 47% of patients < 50 ml, in 15.2 % between 50-100 ml, in 25.8% between 100 and 200 ml and in 12.1% of patients >200ml. The mean volume of the lymphoceles was 111.6 ml (Median 80 ml). 13 patients developed complications such as thrombosis and abscesses. The mean volume of lymphoceles being clinically symptomatic was 227±125ml and in asymptomatic patients it was 87±65 ml. This difference was statistically significant (p<0.001).

Conclusions: Because of simple feasibility, universal availability as well as low costs, a pelvic ultrasound should be performed in the clinical setting after removal of all drains. Asymptomatic lymphoceles with a volume less than 100 ml do not need any particular close follow-up. Facing larger lymphoceles invasive means should be planned rather early to avoid complications.