The Combination of Radiotherapy with Pembrolizumab in the Treatment of Metastatic Melanoma Patients: a Systematic Review

Abstract

Melanoma is a severe form of skin cancer arising from melanocytes. In recent years, immunotherapy in particular, immune checkpoint inhibitor (ICI), has revolutionized the treatment of metastatic melanoma. Recent studies have explored the potential of treatment of metastatic melanoma using the combination of ICI with radiotherapy (RT). In present study, we systematically review available clinical studies involving the combination of RT with pembrolizumab. A systematic search using the electronic databases including PubMed, Scopus, and Embase was conducted to retrieve relevant clinical studies investigating the use of RT+ pembrolizumab on metastatic melanoma patients. Results showed that a total of 16 studies involving 612 metastatic melanoma patients were included. Furthermore, the treatment combination was generally safe with grade 3 or higher toxicities ranging from 1 to 11%. In conclusion, this therapeutic modality is promising. However, gray areas such as limited prospective studies and optimal timing will need to be addressed in future studies.