Lymph node yield during radical prostatectomy does not impact rate of biochemical recurrence in patients with seminal vesicle invasion and node-negative disease

Seminal vesicle invasion (SVI) is a risk factor for poor oncologic outcome in patients with prostate cancer. Modifications to the pelvic lymph node dissection (PLND) during radical prostatectomy (RP) have been reported to have a therapeutic benefit. The present study is the first to determine if lymph node yield (LNY) is associated with a lower risk of biochemical recurrence (BCR) for men with SVI. A total of 220 patients from 2 high-volume institutions who underwent RP without adjuvant treatment between 1990 and 2015 and had prostate cancer with SVI (i.e., pT3b) were identified, and 21 patients did not undergo lymph node dissection. BCR was defined as a postoperative PSA>0.2ng/mL, or use of salvage androgen deprivation therapy (ADT) or radiation. Multivariable Cox proportional hazards models were used to determine whether LNY was predictive of BCR, controlling for PSA, pathologic Gleason Score, pathologic lymph node status, NCCN risk category, etc. The Kaplan-Meier method was used to determine 3-year freedom from BCR. Median number of lymph nodes sampled were 7 (IQR: 3–12; range: 0–35) and 90.5% underwent PLND. The estimated 3-year BCR rate was 43.9%. Results from multivariable analysis demonstrated that LNY was not significantly associated with risk of BCR overall (HR = 1.00, 95% CI: 0.98–1.03; P = 0.848) for pN0 (HR = 0.99, 95% CI: 0.97–1.03; P = 0.916) or pN1 patients (HR = 0.96, 95% CI: 0.88–1.06; P = 0.468). Overall, PSA (HR = 1.02, P2 positive lymph nodes (OR = 1.27, 95% CI: 1.06–1.65, P = 0.023). Seminal vesicle invasion is associated with an increased risk of BCR at 3 years, primarily due to pathologic Gleason score and PSA. Although greater lymph node yield is diagnostic and facilitates more accurate pathologic staging, our data do not show a therapeutic benefit in reducing BCR. •Survival effect of lymph node yield in pT3b patients was analyzed.•Receipt of lymph node yield does not influence biochemical recurrence.•Greater lymph node yield did not influence biochemical recurrence.•PSA and Gleason Score are associated with biochemical recurrence