Resumption of anti‐programmed cell death 1 monotherapy for severe immune‐related adverse events experienced patient with renal cell carcinoma

INTRODUCTION: Combined anti‐cytotoxic‐T‐lymphocyte antigen 4 and programmed cell death 1 blockade induced high rates of immune‐related adverse events in patients with renal cell carcinoma. However, the safety of reinitiating anti‐programmed cell death 1 monotherapy for patients who discontinued combination therapy due to immune‐related adverse events is largely unknown. CASE PRESENTATION: We report the case of 74‐year‐old man who received combination therapy with anti‐cytotoxic‐T‐lymphocyte antigen 4 and programmed cell death 1 inhibitors for advanced renal cell carcinoma. After three cycles of combination therapy, he complained severe immune‐related adverse events including grade 3 nausea and anorexia, and grade 3 diarrhea, leading to discontinuation of the therapy. He started readministration of anti‐programmed cell death 1 monotherapy at 41 weeks after discontinuation due to the new lung metastatic lesion. Importantly, he experienced only grade 1 diarrhea, which can be controlled with prednisolone. CONCLUSION: The readministration of anti‐programmed cell death 1 monotherapy with close monitoring can be an acceptable treatment even after discontinuation of combination therapy.