Anatomical extent of pelvic lymphadenectomy in bladder and prostate cancer

The rationale for locoregional staging lymphadenectomy in prostate and bladder cancer lies in the accurate diagnosis of occult micrometastases in order to stratify patients who might benefit from adjuvant therapeutic measures. In prostate cancer, extended pelvic lymphadenectomy including the lymphatic tissue along the common iliac region with the ureteral crossing as cranial margin, external and internal iliac region and the obturator fossa has been shown to significantly increase the yield of both total lymph nodes and lymph node metastases. The frequency of observed positive lymph nodes in clinically localized and locally advanced prostate cancer is significantly higher than predicted by nomograms such as Partin tables and CART analysis. Although there are no prospective randomized trials demonstrating a survival benefit associated with epLA, there might be an advantage for those with minimal lymph node involvement. Various studies have documented an equal risk of cancer associated mortality in patients with no or only 1-2 positive lymph nodes. Since the surgery associated morbidity of epLA is not increased as compared to standard lymphadenectomy, epLA should be favoured for all patients undergoing radical prostatectomy. For the future, ongoing prospective trials have to demonstrate a benefit in terms of biochemical free and cancer specific survival. In bladder cancer, pelvic lymphadenectomy as a common procedure of radical cystectomy has not been standardized although evidence supports a relationship between the extent of lymph node dissection and therapeutic outcome. Recent retrospective and prospective clinical trials have carefully analysed the distribution of lymph node metastases at time of radical cystectomy thereby identifying those regions which should be included in a standard pelvic lymph node dissection. Dissecting all lymphatic tissue along the common iliac region with the aortic bifurcation as cranial margin, along the external, internal iliac region and the obturator fossa bilaterally will completely clear 80% of all positive nodes. Only if frozen section examination will demonstrate micrometastases at these regions, extending lymphadenectomy further cranially will be worthwile. Currently, epLA in bladder cancer has been shown to improve progression-free survival if > 14 lymph nodes are removed: For the future, prospective trials have to demonstrate a benefit with regard to cancer specific and overall survival and in terms of regional versus distant recurrences. (C) 2005 Published by Elsevier B.V.