Differences in Survival Associated with Performance of Lymph Node Dissection in Patients with Invasive Penile Cancer: Results from the National Cancer Database

Abstract

Purpose: Inguinal lymphadenectomy remains under performed in patients with invasive penile cancer. Using a large national cancer registry we assessed temporal trends in inguinal lymphadenectomy performance and evaluated the impact of the procedure on survival in patients in whom inguinal lymphadenectomy was an absolute indication (T1b-4 N0/x-1) according to NCCN^® (National Comprehensive Cancer Network®) Guidelines®.

Materials and methods: We queried the National Cancer Database for all cases of nonmetastatic, T1b-4 N0/x-1 squamous cell carcinoma of the penis from 2004 to 2014. Multivariable logistic regression models adjusting for patient, demographic, and clinicopathological characteristics were used to examine the association between available covariates and receipt of inguinal lymphadenectomy. Cox proportional hazards regression analysis was then done to assess the impact of clinical and pathological variables on overall survival. Propensity score weighted analysis was performed to assess the effect of inguinal lymphadenectomy on overall survival.

Results: A total of 2,224 patients met analysis criteria, of whom 606 (27.2%) underwent inguinal lymphadenectomy. Following adjustment the procedure was more likely in younger patients, those who presented with palpable adenopathy (cN1), those treated at an academic facility and those with a more contemporary diagnosis. On survival analysis controlling for all known and measured confounders inguinal lymphadenectomy was associated with improved overall survival (HR 0.79, 95% CI 0.74-0.84, p <0.001).

Conclusions: At hospitals that report to the National Cancer Database the overall rate of inguinal lymphadenectomy in patients with invasive penile cancer was only 27.2%. Inguinal lymphadenectomy was associated with increased overall survival, justifying the procedure as an important quality metric for performance reporting in patients with invasive penile cancer.

Keywords: carcinoma; lymph node excision; morbidity; mortality; penile neoplasms; squamous cell.