Purpose: Penile cancer (PC) is an uncommon malignancy in the urinary system of males. The present study aims to compare survival outcomes of PC patients among racial/ethnic groups in the United States.
Methods and materials: Patients with PC were identified in the Surveillance, Epidemiology, and End Results (SEER) registries from 2004 to 2015. The SEER database represents 28% of the U.S. population. Race/ethnicity was categorized as non-hispanic white (NHW), hispanic white (HW), black, Asian/Pacific Islander (A/PI), or American Indian/Alaskan native (AI/AN). Kaplan-Meier method with the log-rank test was used to assess cancer-specific survival (CSS) and overall survival (OS). Multivariate analysis was conducted using Cox’s proportional hazard model.
Results: A total of 3955 patients with PC were included. There were significant differences in age, marital status, tumor location, histology, grade, lymphadenectomy, and radiotherapy according to race/ethnicity. Univariate analysis revealed that A/PIs were significantly associated with better CSS (p= 0.005) and OS (p= 0.025) for most subtypes. The 5-year CSS rates for NHWs, HWs, blacks, A/PIs and AI/ANs were 79.4%, 74.2%, 75.9%, 87.1%, and 78.9%, respectively. The 5-year OS rates for NHWs, HWs, blacks, A/PIs and AI/ANs were 63.4%, 64.1%, 60.5%, 73.0%, and 70.9%, respectively. After adjusting for other factors, racial disparity was an independent risk factor for CSS and OS in the multivariate analysis (p=0.010 and p=0.017, respectively).
Conclusions: Our results suggested that racial differences existed among PC patients in the United States with respect to patient clinicopathological features and survival. Long-term survival disparities were evident in PC patients, that the survival of NHWs, HWs, and blacks was worse than that of A/PIs.