Penile squamous cell carcinoma is a rare form of penile cancer with limited treatment options. An international study led by Yale Cancer Center researchers at Yale School of Medicine finds that the use of immune checkpoint inhibitors (ICIs) offers promising clinical benefits for some patients with advanced penile squamous cell carcinoma. Immune checkpoint inhibitors are immunotherapy drugs that block checkpoint proteins from binding with their partner proteins.
The study was published on August 11 in the Journal of the National Cancer Institute.
“These findings provide encouraging evidence that immune checkpoint inhibitors can be effective in treating a subset of patients with penile squamous cell carcinoma," said co-first author Amin Nassar, a member of Yale Cancer Center and a clinical fellow at Yale School of Medicine. "We believe that further translational studies and biomarker-based research are essential to identify patients most likely to benefit from this therapy and improve the outcomes for individuals with penile cancer."
In this study conducted between 2015 and 2022, researchers assessed the efficacy of ICIs by focusing on an international cohort of 92 patients with locally advanced or metastatic penile cancer. The most common ICIs administered were pembrolizumab, nivolumab, and cemiplimab, but some patients received combination treatment with nivolumab and ipilimumab.
Researchers found that 13% of all patients, and 35% of patients with metastases limited to lymph nodes, responded to ICIs. The average overall survival rate was 9.8 months for patients. Treatment-related adverse events occurred in 29% of patients.
“The study highlights the importance of high-quality, real-world research to advance therapeutic options for this rare cancer,” said co-first author Talal El Zarif, an oncology research fellow at Dana Farber Cancer Institute and a member of Yale Cancer Center. “We are hopeful that response and survival rates will continue to improve for patients fighting penile cancer.”