2022 Volume 64 Issue 4 Pages 992-998
A 78-year-old patient with a pulmonary large cell carcinoma was referred to our department because of hypochromic microcytic anemia after receiving 30 courses of pembrolizumab therapy. Esophagogastroduodenoscopy revealed an esophageal ulcer from the cervical part to the middle thoracic part. Histologic findings showed ulcerative esophagitis with infiltration of neutrophils and granulation tissue. Drug-induced esophagitis and infectious esophagitis were excluded because of the patientʼs drug history and laboratory data. We diagnosed an esophageal immune-related adverse event induced by pembrolizumab. Treatment with vonoprazan was initiated, and pembrolizumab was discontinued. However, he subsequently complained of grade 3 dysphagia, and treatment of colitis by immune checkpoint inhibitors as well as Ⅳ methylprednisolone 1 mg/kg/day was initiated. His dysphagia gradually resolved, and tapering of methylprednisolone therapy was planned. After methylprednisolone therapy for 12 weeks, his symptoms and the esophageal ulcer had completely resolved. Pembrolizumab treatment was not reinitiated. Esophageal immune-related adverse events induced by immune check point inhibitors are rare, but physicians should be aware of this rare manifestation.
