Extended versus limited pelvic lymphadenectomy during radical prostatectomy for intermediate- and high-risk prostate cancer: Early outcomes from a randomized controlled phase III study.

Abstract

5018 Background: The role of extended pelvic lymph node dissection (ePLND) in treating prostate cancer (PCa) patients remains controversial, mainly by the lack of RCTs. Methods: Patients with D'Amico intermediate or high risk PCa, absence of bone metastasis and no previous treatment were prospectively computer randomised to undergo extended or limited PLND (1:1) during radical prostatectomy. Limited PLND (lPLND) included the obturator chain bilaterally; ePLND involved bilaterally chains: obturator, external-, internal-, common-iliac and pre-sacral. Surgical specimens and each chain were analyzed separately, according to College of American Pathologists. All patients signed a free and informed consent and local ethics committee approved the study. The primary endpoint was biochemical recurrence-free survival, analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01812902. Results: Since May 2012 until August 2016, 291 patients were randomly assigned, 145 to ePLND and 146 to lPLND. Preoperative data were comparable between groups. Median follow-up was 35.2 months. EPLND increased significantly operative time (54 minutes), estimated blood loss (100 mL), length of hospital stays (1 day) [p≤0.001], transfusion rate [p = 0.05] and postoperative complications according to Clavien scale [p = 0.03]. There was no difference in Pathologic Gleason grade, T stage or positive surgical margin. On ePLND and lPLND groups, 59.3% and 61.7% were staged ≥ pT3a, respectively. EPLND and lPLND yielded median (mean) 17 (19.8) and 3 (4.1) nodes, respectively (p < 0.001). EPLND showed 6.3 times more lymph node metastases (p < 0.001) and only it was able to show positive nodes in intermediate risk. There were no difference in biochemical recurrence (PSA ≥ 0.2 ng/mL) using Kaplan-Meyer method (p = 0.4), Radiotherapy, Androgen Deprivation Therapy, bone metastases or death. Conclusions: Extended lymphadenectomy in intermediate- and high-risk prostate cancer patients is associated with better tumor staging, increased morbidity and no oncological benefits in this initial short follow-up time. Clinical trial information: NCT01812902.