Given the lack of other precipitating factors for the two endocrinopathies, it was determined that the most likely etiology was recent treatment with pembrolizumab (a PD-1 inhibitor). In our case, pembrolizumab monotherapy developed two irAE (hyperthyroidism and DKA), which is unique as most combined immunotherapy regimens are associated with the development of multiple endocrinopathies. This evidence concerns the gene PDCD1 and endocrine system disorder.