Critical assessment of the European Association of Urology guideline indications for pelvic lymph node dissection at radical prostatectomy

Study Type - Prognosis (retrospective cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Lymphadenectomy is the most accurate lymph node staging procedure in patients with prostate cancer. We presented the first formal validation of the 2010 European Association of Urology guidelines for lymphadenectomy in prostate cancer patients. OBJECTIVE • To assess the 2010 European Association of Urology (EAU) guidelines for prostate cancer, which recommend a pelvic lymph node dissection (PLND) at radical prostatectomy in all individuals with a nomogram-predicted lymph node invasion (LNI) risk of >7%. PATIENTS and methods • We focused on 1520 patients treated with radical prostatectomy and PLND, between 2006 and 2010, at a single European institution. We examined the ability of the EAU proposed threshold to correctly predict histologically confirmed LNI. Moreover, we tested the ability of a range of nomogram thresholds between 1 and 14% to correctly predict histologically confirmed LNI. Finally, we externally validated the EAU PLND guideline nomogram. RESULTS • Overall, 10.6% of patients had LNI. The use of the 7% limit would have allowed the avoidance of 49% of PLNDs, at the cost of missing 11% of patients with LNI. The use of thresholds of 6% and 8% would have allowed the avoidance of respectively 46% and 52% of PLNDs, at the cost of missing respectively 9% and 11% of patients with LNI. Overall, the accuracy of the EAU guideline nomogram according to the receiver operating characteristics derived area under curve was 81% CONCLUSION • Our observations indicate that the EAU guideline nomogram is highly accurate. The recommended threshold of 7%, above which a PLND should be performed, is associated with a favourable compromise between avoidable PLNDs and potentially missed LNI cases.