Extended versus limited pelvic lymph node dissection and long‐term outcomes in high‐risk prostate cancer before radiotherapy

Abstract Objectives To compare oncological outcomes after extended pelvic lymph node dissection (PLND) versus limited in patients with high‐risk prostate cancer (PCa) undergoing curative external beam radiation therapy (EBRT). Patients and Methods From 3627 men with PCa at a single centre between 2000 and 2013, 167 with high‐risk, age ≤75, Gleason score 6–10, clinical stage T1–T3, PSA < 100 ng/ml, no distant metastases (M1) and node‐negative at the obturator fossa, underwent PLND before curative EBRT. Of these, 90 received limited, and 77 underwent extended PLND. Mean follow‐up (SD) was 14.9 yr (5.8) for the limited and 12.3 yr (3.3) for the extended PLND. Primary endpoint was biochemical recurrence (BCR), secondary M1, cancer–specific mortality (CSM), overall mortality (OM). HR, KM and Cox regression models adjusted for age and Cambridge prognostic group (CPG) score. RR, RD at 11 yr. Results Extended PLND was associated with a significantly lower risk for BCR (HR: 0.51, 95% CI: 0.31–0.86, p = 0.01) (RR: 0.43, 95% CI: 0.26–0.69, p = 0.001 ), lower risk of M1 (HR: 0.22, 95% CI: 0.08–02.65, p = 0.006 ) (RR: 0.26, 95% CI: 0.09–0.73, p = 0.004 ) and lower CSM compared with limited PLND (HR: 0.31, 95% CI: 0.08–0.65 p = 0.035) (RR 0.27, 95% CI: 0.08–0.91, p = 0.028). OM did not differ significantly. Conclusions Extended PLND prior to curative ERBT shows reductions in BCR, M1 and CSM long‐term outcomes following extended versus limited PLND. Extended PLND can be considered in cases with high‐risk PCa prior to curative EBRT.