97 Background: Type 1 diabetes mellitus (T1D) as an immune-related adverse event (irAE) is found in 0.5-5% of all patients treated with immunotherapy (IT) and it is associated with life-threatening complications. However, there are no official guidelines that suggest methods for the prevention and monitoring of T1D during treatment with IT. The algorithms described in the literature only assess the fasting blood sugar levels for prevention and monitoring. The objective of this review is to find factors that establish a relationship with the appearance of T1D as an irAE and to put forward a new algorithm for prevention and monitoring based on those findings. Methods: We carried out a clinical review of the cases published in the literature on T1D secondary to IT between 2012 and 2019. Through a statistical analysis, the relevant clinical characteristics will be determined, together with the factors related to the appearance of T1D, which will make it possible to put forward a new algorithm for the prevention and monitoring of T1D during treatment with IT for solid tumors. Results: Eighty one cases were reported. Of the reported cases, 90% were associated with Nivolumab or Pembrolizumab. The median age was 67 years (23-84 years), and the patients were predominantly men. The average number of administered doses was 5.3 with a lapse of 14.6 weeks from the administration of the first dose until diagnosis. In 48 cases (59%) the levels of C-peptide were low or undetectable, and the glycosylated hemoglobin (HbA1c) levels were elevated by an average of 8.8% (73 mmol/mol). Anti-β-cell antibodies were found in less than half of the patients (44). Diabetic ketoacidosis was observed at diagnosis in 61 patients (75%). Conclusions: Based on the results of our review, we propose including the levels of C-peptide and HbA1C in the usual protocol for the management of adverse events related to IT. Our algorithm suggests that the levels must be determined prior to the IT, after the first 2 cycles, and then every 2 months. This algorithm will enable the prevention, early diagnosis and monitoring of T1D during treatment with IT.
Islet cell antibodies and fasting C-peptide predict insulin requirement at diagnosis of diabetes mellitus
