2023 Volume 66 Issue 5 Pages 333-338
A 69-year-old man receiving insulin therapy for type 2 diabetes mellitus was treated with nivolumab for lung adenocarcinoma. During 3 years of nivolumab treatment, his insulin requirement increased and his glycemic control worsened. After 59 courses of nivolumab, he presented to the hospital with anorexia and fatigue and was admitted with a diagnosis of diabetic ketoacidosis. His endogenous insulin secretory capacity was significantly reduced, despite negative test results for islet-related autoantibodies. Imaging studies revealed that his pancreas had atrophied in comparison to before the start of nivolumab. Recently, in addition to new-onset type 1 diabetes, pancreatic atrophy has been reported in some patients treated with immune checkpoint inhibitors. The present case suggests a potential association between severe pancreatic atrophy observed during immune checkpoint inhibitor treatment and exacerbations of type 2 diabetes, including the onset of diabetic ketoacidosis.
