Examining the association between real-world extended vs. standard pelvic lymph node dissection and early and late oncologic outcomes in men undergoing radical prostatectomy.

INTRODUCTION

In patients with prostate cancer (PCa), the impact of extended pelvic lymph node dissection (E-PLND) during radical prostatectomy (RP) on oncologic outcomes remains controversial. This study examined the association between extended vs. standard PLND (S-PLND) and biochemical recurrence (BCR), an early outcome, as well as metastatic PCa (mPCa), and castration-resistant PCa (CRPC) development, late outcomes, in a multi-institutional cohort.

METHODS

High-risk post-RP patients from a Canadian PCa database were analyzed from January 1, 2005, to December 31, 2016. The association between PLND and BCR, mPCa, and CRPC development and complication rate was examined using regression and correlation analysis.

RESULTS

Data were collected from patients who underwent S-PLND (n=494) and E-PLND (n=107). The median followup was 40.1 months, and time to BCR, mPC, and CRPC development was 9.8, 46.0, and 52.1 months, respectively. The median (interquartile range) number of lymph nodes extirpated was 7 (7) and 14 (11) for the S-PLND and E-PLND groups, respectively. E-PLND was associated with increased intraoperative blood loss and higher postoperative complication rate. There were no differences in BCR-free survival based on PLND approach, with 67.1% of S-PLND cases and 71.1% of E-PLND cases reaching BCR-free survival at the end of the followup period (hazard ratio [HR] 0.784 [0.506, 1.215], p=0.28). PLND extent was not a predictor for mPCa progression (p=0.963). Similarly, there were no differences in CRPC-free survival based on dissection type (S-PLND 90.9% vs. E-PLND 89.1%, p=0.561). Lymph node positivity was predictive of BCR, mPCa, and CRPC progression.

CONCLUSIONS

E-PLND did not show significant differences in the rates of BCR, mPCa, or CRPC progression when compared to S-PLND. E-PLND was associated with higher complication rates. This study adds to the data exploring the association between PLND and PCa oncologic outcomes.