Clinical Outcomes in Clinical N0 Squamous Cell Carcinoma of the Penis According to Nodal Management: Early, Delayed or Selective (following Dynamic Sentinel Node Biopsy) Inguinal Lymph-Node Dissection

Abstract

Introduction: We evaluated the oncologic efficacy of early inguinal lymph-node dissection (ILND), observation or dynamic sentinel node biopsy (DSNB) followed by delayed or selective ILND in cN0 patients with penile squamous cell carcinoma (peSCC). Patients and Methods: Between 1980 and 2017 included, 296 evaluable consecutive cN0 peSCC patients underwent early ILND (16), observation (114) or DSNB (166). Median follow-up was 50 months. Tumor stage, grade, lympho-vascular invasion (LVI) and age were considered. Kaplan-Meier plots illustrated 5-year inguinal relapse (IR)-free and cancer specific survival (CSS) rates. Multivariable Cox Regression models (MCRMs) tested the treatment effect. Analyses were repeated after inverse probability of treatment weighting adjustment (IPTW). Results: The 5-year IR-free survival and CSS rates following early, observation and DSNB ILND were 100%, 87%, 89%, and 84%, 81%, 85%, respectively. The 5-year crude IR-free survival and CSS rates were 90% and 93% in low-risk patients undergoing observation. Clavien grade 3 complications were 0.6 Vs 12.5% in DSNB and early ILND group, respectively. After IPTW adjustment, 5-year IR and CSS were 90% vs 73% and 90% vs 77% following DSNB and observation, respectively. At MCRMs, patients undergoing DSNB had significantly lower IR (HR 0.4, CI 0.2-0.85, p 0.02) and CSM (HR 0.29, CI 0.11-0.77; p- 0.01) compared to those under observation. The low number of patients undergoing early ILND made a reliable comparison with this group impractical. Conclusions: Selective ILND following DSNB significantly improved IR and CSM when compared with observation, providing evidence of efficacy of DSNB in clinical stage N0 peSCC patients.