Prognostic Significance of Extranodal Extension in Patients With Pathological Node Positive Penile Carcinoma

Abstract

We assessed the prognostic significance of extranodal extension, defined as tumor extension through the lymph node capsule into the perinodal fibrous-adipose tissue, as well as several other risk factors in node positive penile cancer cases. We analyzed prospectively collected data on a consecutive series of 156 chemotherapy naïve patients with proven lymph node involvement who underwent therapeutic regional lymphadenectomy. Postoperative external radiotherapy was indicated when histopathological analysis revealed more tumor than 1 intranodal metastasis. We estimated cancer specific survival using the Kaplan-Meier method. Multivariate analysis was done according to the Cox proportional hazards model of factors statistically significant on univariate analysis. Adjuvant radiotherapy was done in 70 patients (45%). Median followup was 57.8 months. Overall 5-year cancer specific survival was 61%. Men with extranodal extension had significantly decreased 5-year cancer specific survival compared with men without it (42% vs 80%). Other prognostic variables on univariate analysis were bilateral metastatic involvement vs unilateral, 3 or greater unilateral metastatic inguinal nodes vs 2 or fewer, inguinal lymphadenectomy positive margin status vs negative status and pelvic lymph node involvement. Pathological T stage or differentiation grade were not significant predictors of outcome. On multivariate analysis extranodal extension and pelvic lymph node involvement remained associated with decreased cancer specific survival (HR 2.37 and 2.20, respectively). Metastatic inguinal lymph node extranodal extension and pelvic lymph node involvement are independent predictive parameters of cancer specific survival in patients with pathologically node positive penile carcinoma despite surgery with postoperative radiotherapy.