Prognostic significance of the degree of extranodal extension in patients with penile carcinoma

Abstract

This study sought to assess the prognostic significance of the degree of extranodal extension (ENE) and several other risk factors in pathological ENE penile carcinoma. We analyzed prospectively collected data on a consecutive series of 31 chemotherapy-naive patients with proven ENE who underwent therapeutic regional lymphadenectomy. Postoperative external radiotherapy was then performed. We studied the extent of ENE utilizing a novel grading system and correlated patient grades with their outcome measures. ENE was graded as 1 - if the capsule of the lymph node (LN) was ruptured less than one-third of its circumference or 2 - if the capsule was disrupted more than one-third of its circumference or the entire LN was disrupted. We estimated overall survival (OS) using the Kaplan-Meier method. Multivariate analysis was performed according to the Cox proportional hazards model using factors that were identified as statistically significant in univariate analysis. The incidence rate of ENE was 51.8% in patients with pathological node-positive carcinoma of the penis. The median OS and 5-year survival were 18 months (95% confidence interval (CI), 14.4-21.6) and 23%, respectively. Prognostic variables on univariate analysis were ENE grade 2, ≥3 LNs with ENE, maximal LN ≥ 35 mm, ≥5 positive LNs and pelvic LN involvement. On multivariate analysis, only ENE grade 2 remained associated with decreased OS (hazard ratio (HR): 6.50). In conclusion, patients with ENE have a poor outcome, and ENE grade 2 is an independent predictive factor of poor OS in patients with pathological ENE penile carcinoma.

Keywords

• extranodal extension; neoplasm metastasis; penile neoplasms; penis; prognosis