Influence of Race/Ethnicity and Household Median Income on Penile Cancer Mortality.

Abstract

Penile cancer, while relatively rare in developed nations, presents substantial disparities in outcomes among different demographic groups. Previous research has shown race/ethnicity and socioeconomic status, often proxied by household median income, to be critical determinants of health outcomes across various diseases. This study examines the association of race/ethnicity and household median income with survival among penile cancer patients in the United States. We utilized the Surveillance, Epidemiology, and End Results (SEER) Registry to identify patients with a primary diagnosis of penile malignancies from 2000 to 2019. Our primary outcome of interest was the hazard of death following a diagnosis of penile cancer. We utilized the Cox regression model to explore the association between race/ethnicity and median household income and how this influences survival among these patients. We adjusted for patients' characteristics, disease stage at presentation, and treatment modalities. Of the 6,520 penile cancer patients identified, 5,242 (80.4%) had primary malignancies. The distribution of patients was as follows: 64.1% non-Hispanic Whites, 8.9% non-Hispanic Blacks, 20.8% Hispanics, and 6.2% from other racial/ethnic groups. The median diagnosis age was 66 years (interquartile range: 56-74). Survival rates at 5, 10, and 15 years showed racial disparities: 76.4%, 72.5%, and 69.7% for non-Hispanic Whites; 70.6%, 64.1%, and 61.1% for non-Hispanic Blacks; and 70.5%, 67.4%, and 65.6% for Hispanics. Multivariate Cox regression revealed worst survival for Black (HR=1.40; 95% CI=1.08-1.81, p=0.01) and Hispanic patients (HR=1.24; 95% CI=1.01-1.52, p=0.04). No association was found between median household income and survival. Interaction analysis indicated that the poorest Black men had worse outcomes than the poorest Whites did (HR=2.08; 95% CI=1.27-3.41, p=0.003). Survival rates for non-Hispanic Black and Hispanic patients are significantly lower than those for non-Hispanic Whites. Furthermore, survival is worse for low-income Black patients than their White counterparts in the same income bracket.