Response of Metastatic Chordoma to the Immune Checkpoint Inhibitor Pembrolizumab: A Case Report

gene, which may be associated with beneficial responses to immunotherapies. The patient received pembrolizumab, an immune checkpoint inhibitor (ICI) that targets the PD-1 receptor of lymphocytes, as second-line therapy, which he tolerated well (the most frequent adverse events were abnormal liver function and hyperglycemia, both of which were only grades 1-2), and achieved a PFS duration of 9.3 months. We hope these results will promote further research that will clarify the mechanisms underlying this beneficial response and that will further explore the use of immunotherapies in this population.