A Case of Fulminant Type 1 Diabetes Mellitus After the Administration of Durvalumab for Small-cell Lung Cancer

Abstract

━━ Background. Fulminant type 1 diabetes mellitus caused by immune checkpoint inhibitors is a rare adverse event. In lung cancer, several cases have been reported in non-small-cell lung cancer. We herein report a patient with small-cell lung cancer who developed fulminant type 1 diabetes mellitus after administration of durvalumab. Case. A 71-year-old man with extensive-stage small-cell lung cancer (cT4N3M1b, stage IVA) with no history of diabetes mellitus received combination therapy of carboplatin, etoposide, and durvalumab on May 20XX. He became aware of anorexia and fatigue on day 27. He was diagnosed with fulminant type 1 diabetes mellitus caused by durvalumab with hyperglycemia of 761 mg/dl, positive urine ketones, and urinary C-peptide of 3.9 μg/ day on the second course of treatment (day 30). After his blood glucose level had been stabilized with insulin therapy, an additional three cycles of chemotherapy with carboplatin and etoposide were administered. A significant response was achieved, and the patient survived without disease progression. Conclusion. Fulminant type 1 diabetes mellitus caused by durvalumab for small-cell lung cancer is a rare but urgent immune-related adverse event that requires attention.