Incidence trends and survival outcomes of penile squamous cell carcinoma: evidence from the Surveillance, Epidemiology and End Results population-based data

BACKGROUND: To provide the latest incidence trends and explore survival outcomes of penile squamous cell carcinoma (PSCC) patients with or without a previous primary malignancy. METHODS: Patients diagnosed with PSCC between 1975 and 2016 in the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively included. Then, we calculated the age-adjusted incidence rates (IRs) and annual percentage changes (APCs). Multivariate Cox analysis and Kaplan-Meier (KM) survival curves were conducted to investigate prognostic variables for cancer-specific survival (CSS). RESULTS: A total of 6,122 PSCC patients were enrolled, 1,137 of whom had a prior malignancy. The age-adjusted IR for the general population in men declined before 1987, fluctuated slightly between 1987 and 1997, and showed an upward trend after 1997, which was basically consistent with that in patients without a previous primary malignancy. The incidence trend of PSCC in the general population was similar with that in those without a previous malignancy. However, the IRs of PSCC in men with a previous malignancy have been increasing since 1975 regardless of race. Furthermore, age at diagnosis, pathological grade, extent of disease, marital status, the administration of surgery and presence of previous primary malignancy were identified to be significantly related to CSS. CONCLUSIONS: The IRs of PSCC have been increasing in recent years. Several independent prognostic factors for CSS were identified, allowing surgeons to assess the individualized risk in advance.