Impact of lymph node yield on biochemical recurrence in patients with high-risk prostate cancer after robot-assisted radical prostatectomy.

BACKGROUND

This study evaluated the association between lymph node yield (LNY) and biochemical recurrence (BCR) after radical prostatectomy with pelvic lymph node dissection (PLND) in patients with intermediate to very high-risk prostate cancer.

METHODS

In total, 1234 patients with intermediate to very high-risk prostate cancer who underwent robot-assisted radical prostatectomy between 2004 and 2025 were reviewed. Patients were compared according to the median LNY, subgroup analyses were performed according to pathological nodal status and NCCN risk classification. Propensity score was used to match the pathological factors between LND groups. BCR-free survival and its predictors were assessed using the Kaplan-Meier method and Cox proportional hazard models.

RESULTS

According to NCCN classification, 18%, 49%, 25%, and 8% of patients were classified as favorable intermediate, unfavorable intermediate, high, and very high risk, respectively. The median follow-up period was 5.0 (interquartile range/IQR 2.6, 8.2) years, and 28% of patients developed BCR. The median LNY was 7 (IQR 4-11). Among patients without pN+ disease, 10-year BCR-free survival rates were 60% in those with LNY ≥ 7, compared with 48% in those with LNY < 7 (p = 0.032). This association was statistically significant only in the high-risk subgroup (p = 0.028). Race, PSA level, Gleason grade group ≥ 4, extraprostatic extension, seminal vesicle invasion, lymphovascular invasion, positive surgical margin, pN+ , and LNY ≥ 7 were independent predictors of BCR.

CONCLUSIONS

Higher LNY was independently associated with improved BCR-free survival in node-negative patients undergoing limited PLND. More lymph node dissection in limited PLND may benefit selected high-risk patients.