免疫チェックポイント阻害剤投与後に溶血性貧血をきたした肺腺癌の 1 例

Background. Autoimmune hemolytic anemia is reported to be associated with the use of immune checkpoint inhibitors, and steroid therapy is recommended as the first choice of treatment. Case. A 61-year-old woman was treated with carboplatin＋pemetrexed＋pembrolizumab as first-line treatment for postoperative recurrence of lung adenocarcinoma. Anemia was detected at the start of the third-line treatment, and the patient was diagnosed with autoimmune hemolytic anemia based on the clinical course and increased peripheral blood reticulocyte count, increased serum levels of bilirubin and LDH, and a decreased serum level of haptoglobin. Treatment with prednisolone showed limited efficacy. She was started on rituximab in addition to steroid therapy, but died of progression of lung cancer 3 days after the initiation of rituximab therapy. Conclusion. The accumulation of cases of autoimmune hemolytic anemia associated with the use of immune checkpoint inhibitors is desired.