LAPAROSCOPIC PELVIC LYMPH-NODE DISSECTION FOR PROSTATE-CANCER - COMPARISON OF THE EXTENDED AND MODIFIED TECHNIQUES

Purpose: We compared the results of extended (obturator, hypogastric, common and external iliac nodes) to modified (obturator and hypogastri c nodes only) laparoscopic pelvic lymph node dissection in patients wi th clinically localized prostate cancer. Materials and Methods: A tota l of 189 patients with stage T1 to T3 prostate cancer underwent modifi ed (150) or extended (39) laparoscopic pelvic lymph node dissection fo r pelvic nodal assessment before definitive treatment. Results: Twice as many lymph nodes were removed via extended than modified laparoscop ic pelvic lymph node dissection (mean 17.8 versus 9.3). The overall po sitivity rate was 23 of 189 lymph nodes (12.2%), including 14 of 150 ( 7.3%) for modified and 9 of 39 (23.1%) for extended dissection (p = 0. 02). Two patients (22%) who underwent extended dissection had positive lymph nodes in the external iliac area. Patients who presented with t he high risk features of prostate specific antigen (PSA) greater than 20 ng./ml., Gleason score 7 or greater, or stage T2b disease or greate r had a 26.5% (p = 0.0002), 22% (p = 0.0006) or 16.4% (p = 0.003) like lihood of positive lymph nodes, respectively. For extended versus modi fied laparoscopic pelvic lymph node dissection node positivity in high risk patients was 27% versus 18.8% (p = 0.4), 30 versus 26.4% (p = 0. 8) and 25.4 versus 14.6% (p = 0.17) for Gleason score 7 or greater, PS A greater than 20 ng./ml. and disease stage T2b to T3a, respectively. Patients who underwent the extended procedure had a higher complicatio n rate (35.9 versus 2%, p <0.0001). No laparotomy was required. Conclu sions: Despite yielding a a-fold higher node count and higher node pos itivity rate, extended laparoscopic pelvic lymph node dissection offer s no advantage over modified laparoscopic pelvic lymph node dissection for diagnosing positive lymph nodes when results are analyzed by prog nostic factors. The extended procedure is associated with a much highe r complication rate. In patients with the high risk features of PSA gr eater than 20 ng./ml., Gleason score 7 or greater and stage T2b to T3a disease modified laparoscopic pelvic lymph node dissection can be per formed safely and effectively to help identify those who may benefit m ost from curative therapy.