Patterns of Pelvic Lymph Node Dissection at the Time of Radical Prostatectomy for Low-risk Men

Biochemical Relapse in Low-risk Prostate Cancer Treated with Radical Prostatectomy and Bilateral Pelvic Lymphadenectomy

Introduction For low-risk prostate cancer (PCa), curative treatment with radical prostatectomy (RP) can be performed, reporting a biochemical relapse-free survival rate (bRFS) at 5 and 7 years of 90.1% and 88.3%, respectively. Prostatic specific antigen (PSA), pathological stage (pT), and positive margins (R1) are significant predictors of biochemical relapse (BR). Even though pelvic lymphadenectomy is not recommended during RP, in the literature, it is performed in 34% of these patients, finding 0.37% of positive lymph nodes (N1). In this study, we aim to evaluate the 10-year bRFS in patients with low-risk PCa who underwent RP and extended pelvic lymph node dissection (ePLND).

Methodology All low-risk patients who underwent RP plus bilateral ePLND at the National Cancer Institute of Colombia between 2006 and 2019 were reviewed. Biochemical relapse was defined as 2 consecutive increasing levels of PSA > 0.2 ng/mL. A descriptive analysis was performed using the STATA 15 software (Stata Corp., College Station, TX, USA), and the Kaplan-Meier curves and uni and multivariate Cox proportional hazard models were used for the survival outcome analysis. The related regression coefficients were used for the hazard ratio (HR), and, for all comparisons, a two-sided p-value ˂ 0.05 was used to define statistical significance.

Results Two hundred and two patients met the study criteria. The 10-year bRFS for the general population was 82.5%, statistically related to stage pT3 (p = 0.047), higher Gleason grade group (GG) (p ≤ 0.001), and R1 (p ≤ 0.001), but not with N1. A total of 3.9% of the patients had N1; of these, 75% had R1, 25% GG2, and 37% GG3. Among the N0 (non-lymph node metástasis in prostate cáncer) patients, 31% of the patients had R1, 41% GG2, and 13% GG3.

Conclusions Our bRFS was 82.5% in low-risk patients who underwent RP and ePLND. With higher pT, GG, and presence of R1, the probability of BR increased. Those with pN1 (pathologicaly confirmed positive lymph nodes) were not associated with bRFS, with a pN1 detection rate of 3.9%.

Details: In low-risk PCa, curative treatment with RP can be performed, reporting a bRFS rate at 5 and 7 years of 90.1% and 88.3%, respectively. Despite the fact that pelvic lymphadenectomy is not recommended during RP in clinical guidelines, in the literature, it is performed in 34% of these patients, finding 0.37% of N1. In this study, we report the 10-year bRFS in patients with low-risk PCa who underwent surgery.

Factors Affecting Transperitoneal Robot-Assisted Laparoscopic Radical Prostatectomy

Objectives: To evaluate the impact of body mass index (BMI), preoperative risk classification, previous inguinal herniotomy, and abdominal operations on several steps of robot-assisted radical prostatectomy (RARP) and lymph node (LN) involvement. Methods: A total number of 225 consecutive patients were included in the study who underwent transperitoneal RARP by 1 surgeon. We defined the following parameters as dependent variables: duration of prostatectomy, duration of pelvic lymphadenectomy, incision to suture time, console time, number of dissected LNs and number of positive LNs for metastasis. We assessed the impact of the following covariates using univariate nonparametric and multivariate analysis: BMI, preoperative D'Amico risk classification, history of inguinal herniotomy, and previous abdominal operations. Results: We observed a statistically significant difference among our three BMI groups (<25, ≥25 and <30, and ≥30 kg/m²) regarding pelvic lymphadenectomy and LN metastasis. Moreover, among the three risk groups (low, intermediate, and high) duration of prostatectomy, pelvic lymphadenectomy, and LN metastasis were statistically different. Previous abdominal operations have been also demonstrated to significantly influence the pelvic lymphadenectomy. In addition, our multivariate model proved the impact of our covariates on pelvic lymphadenectomy. Conclusions: Our findings highlight the impact of BMI and preoperative risk on various steps of RARP. We revealed longer duration of pelvic lymphadenectomy and more nodal yield in patients with higher BMI and high-risk disease. Therefore, we suggest that BMI and risk classification according to D'Amico should be taken into account while a RARP is being planned.

Influence of pelvic lymph node dissection and node-positive disease on biochemical recurrence, secondary treatment, and survival after radical prostatectomy in men with prostate cancer

BACKGROUND

The benefit of pelvic lymph node dissection (PLND) at radical prostatectomy (RP) remains unclear given the low prevalence of known nodal disease (pN1) and concerns about its therapeutic utility.

OBJECTIVE

To characterize the impact of PLND and secondary treatment on oncologic outcomes.

DESIGN, SETTING, AND PARTICIPANTS

Cohort study of men who underwent primary RP with PLND for prostate cancer (PCa) at our institution since 2003. Men stratified by nodal status.

OUTCOME MEASURES AND STATISTICAL ANALYSIS

Outcomes include biochemical recurrence-free survival (bRFS), overall survival, and PCa-specific mortality (PCSM). Multivariable Cox regression models used for each outcome.

RESULTS AND LIMITATIONS

Of 1,543 men who underwent primary RP, 174 (11%) had pN1 disease. Median follow-up was 34 months (interquartile range, 15-62). Seven-year outcomes were similar whether less than or ≥14 LNs dissected. Among node-positive patients, 29% had undetectable (UDT) prostate-specific antigen (PSA), 11% had UDT PSA + adjuvant therapy, and 60% had detectable PSA, and 7-year bRFS differed (75% for UDT PSA, 90% for UDT + adjuvant therapy, 38% for detectable PSA, p < .01). Survival outcomes did not differ. In multivariable analysis, detectable PSA (vs. UDT, HR 5.2, 95% CI 2.0-13.3) associated with worse bRFS. After salvage treatment, 7-year outcomes did not differ between groups. Study limited by retrospective review.

Utilization of Pelvic Lymph Node Dissection for Patients With Low-Risk Prostate Cancer Treated With Robot-Assisted Radical Prostatectomy

INTRODUCTION

Pelvic lymph node dissection (PLND) is not recommended for low-risk prostate cancer (PCa) patients. However, the rate of PLND in this population is unknown.

METHODS

We queried the National Cancer Data Base for PCa patients who underwent robot-assisted radical prostatectomy from 2010 to 2013 and stratified them by D'Amico risk classification. We identified the frequency of PLND in low-risk patients and identified factors associated with receipt of PLND. Further, we determined the number of lymph nodes evaluated (quality) and proportion of patients with detected nodal metastatic disease (utility) in each risk group.

RESULTS

Of 51,971 patients with low-risk PCa who underwent robot-assisted radical prostatectomy, 19,059 (36.7%) received PLND. Predictors of PLND in low-risk patients included rural residence (odds ratio [OR], 1.157; 95% confidence interval [CI], 1.009-1.327), treatment at an academic center (OR, 1.492; 95% CI 1.188-1.874), and high-volume facility (OR, 1.327; 95% CI, 1.078-1.633). The mean number of lymph nodes obtained in low-risk patients was lower than in intermediate/high-risk patients (4.74 vs. 5.86, P < .0001). Lymph node positivity was identified in 0.4% of low-risk patients and 4.6% of intermediate/high-risk patients.

CONCLUSION

While PLND is not recommended for low-risk PCa by clinical practice guidelines, it was performed frequently (36.7%) in a large hospital-based data set. PLND in this population was of lower quality (nodal yield) and had less utility of detecting nodal metastatic disease than PLND in intermediate/high-risk PCa. Treatment at a high-volume or academic center was associated with increased use of PLND. Reasons for the variation in practice patterns should be investigated to improve the value of PCa care.