Outcomes of Adjuvant Radiation Therapy in Penile Cancer

This study evaluates the long-term outcomes of adjuvant radiation therapy (RT) in patients with penile cancer treated over 14 years.

In this retrospective cohort study, patients with squamous cell carcinoma of the penis who underwent surgery followed by adjuvant RT with or without concurrent chemotherapy from January 2010 to December 2022 were included, with follow-up continuing until December 2023. Primary endpoints were overall survival (OS) and recurrence-free survival (RFS), with additional analyses of toxicity and recurrence patterns. Survival rates were estimated using the Kaplan-Meier method, and univariate analysis was performed using Cox proportional hazards regression to assess the associations between clinical variables and outcomes (OS and RFS). Hazard ratios with 95% CIs were calculated, and a P value of <.05 was considered statistically significant.

A total of 30 patients met the selection criteria. The median age was 57 years (IQR, 52-63), with a median follow-up of 84 months (95% CI, 74.02-92.81 months). The median OS was 77.2 months, while the median RFS was not reached. Five-year and 7-year survival rates were 52% and 46%, respectively. The 5-year RFS was 66%. Among 8 patients with recurrence, 6 had locoregional and 2 had distant metastasis. RT was generally well tolerated, with lymphedema as the most common side effect.

Despite adjuvant RT, survival outcomes remain suboptimal, with high rates of locoregional relapse. These findings underscore the need for improved treatment strategies.