The Prognostic Ability of Staging System in Men with Penile Cancer: An Analysis of SEER Database

Aditya Jalan,Gyan Prasad Pokhrel,Nirmal Lamichhane,Rajeev Kumar Malhotra,Ravi Kanodia,Sarita Rana Gurung,Umesh Nepal

doi:10.3126/njc.v4i1.31787

Abstract

Background: Penile cancer is now a rare condition. The low incidence of the disease makes a valid estimation of its prognosis difficult. In this study, we made an attempt and propose a nomogram to develop a prognostic rule that could predict the Cancer-Specific Mortality (CSM) free rates in patients with primary penile squalors cell carcinoma of the penis (PPSCC).Methods: This study included 1304 patients diagnosed with PPSCC between the years 2004 & 2011 and treated with penile tumor excision. Subjects were staged as per Surveillance, Epidemiology & End Results stage (SEER), American Joint Committee on Cancer (AJCC), TNM classification and tumor grade (TG). CSM free rates were determined. Univariate and multivariate Cox regression model was used to test the prediction of the CSM free rate. The predictive rule accuracy was created using the receiver operating characteristic curve. Results: The clinico-pathological profile depicts a mean age of 64.66 ± 14.38 yrs. The most common primary site involved was glans penis (n= 483, 37%) and the disease was most commonly diagnosed at AJCC stage I (n= 670, 51.4%) disease. The cumulative 5-year CSM free rates according to Fine & Gray, & Kaplan-Meier methods were 81.8% and 79.8%, respectively. The predictive accuracy as per SEER stage, AJCC stage, TNM stage alone were 68.8%, 70.3%, 72.3%, respectively. When TG was combined, the predictive accuracy increased to 72.8%, 73.1%, and 75.0%, respectively. TNM stage with TG was most accurate in predicting CSM free rate compared to other models. Conclusions: TNM stage with TG and AJCC stage with TG appear to have comparable accuracy to predict the CSM free rate in patients with PPSCC, the TNM stage with TG is the most accurate (75%) method to predict the CSM free rates. The addition of the TG variable improved the accuracy of these prognostic models.

Highlights

Penile cancer is a rare condition, accounting for less than 1% of cancers diagnosed in men in the United States
The most common primary site involved was glans penis (n= 483, 37%) and the disease was most commonly diagnosed at American Joint Committee on Cancer (AJCC) stage I (n= 670, 51.4%) disease
The cumulative 5-year Cancer-Specific Mortality (CSM) free rates according to Fine & Gray, & Kaplan-Meier methods were 81.8% and 79.8%, respectively

Summary

Introduction

Penile cancer is a rare condition, accounting for less than 1% of cancers diagnosed in men in the United States. The disease itself is a challenge for urologist and onco-surgeons as it carries significant morbidity and mortality with approximately 50%, 5-year cancer-specific survival.[1] With an improvement in the understanding of the natural history of the disease, the cure rate has increased from 50% in 1990 to 80% in recent years.[2] Lower incidence of the disease makes the valid estimation of prognosis of primary penile squamous cell carcinoma (PPSCC) difficult. We made an attempt and propose a nomogram to develop a prognostic rule that could predict the Cancer-Specific Mortality (CSM) free rates in patients with primary penile squamous cell carcinoma of the penis (PPSCC)

Methods

Results

Conclusion