Combined Application of Nivolumab and Intravesical Bacillus Calmette-Guérin Led to Acute-Onset Type 1 Diabetes.

We report a case of acute-onset type 1 diabetes due to combined application of nivolumab and intravesical Bacillus Calmette-Guérin (BCG). An 84-year-old woman underwent lung resection for pulmonary squamous cell carcinoma. She had been treated for type 2 diabetes and later experienced lung cancer recurrence.