Chronic hyperglycemia based on diabetes is independently associated with decreased survival in patients with advanced cancer treated with immune checkpoint inhibitors.

Immune checkpoint inhibitors (ICIs) have started a new era in treating patients with cancer. The effect of comorbidities and concomitant drug use on ICIs have become of interest in those patients. Data about the impact of hyperglycemia on response to ICIs in cancer patients are limited. All advanced-stage cancer patients treated with ICIs in Ankara University Medical Oncology Department were retrospectively evaluated. Patients treated in expanded access programs or clinical trials were excluded from the study. A total of 137 patients were included in this study. The most common primary tumor type was malign melanoma (32.8%) and nivolumab (62.3%) was the most common used ICI. More than half of patients (57.7%) had lung metastasis at the initiation of ICIs. Thirty-five patients (25.5%) had diabetes before initiating ICIs. Median baseline fasting glucose level was higher in patients with diabetes than those without diabetes (117 mg/dl vs. 99 mg/dl, P  = 0.002). In all patients, median overall survival and progression-free survival were 11.3 [95% confidence interval (CI), 8.1-14.4) and 5.9 (95% CI, 3.6-8.3) months, respectively. In multivariate analysis, diabetes was found to increase risk of death [hazard ratio (HR), 2.09; 95% CI, 1.27-3.43, P  = 0.004) and disease progression (HR, 2.01, 95% CI, 1.29-3.09, P  = 0.002). Hyperglycemia might decrease response to ICIs in patients with advanced cancer. This research area is still an unmet need in the immunotherapy era. Prospective studies are needed to elucidate the effect of hyperglycemia on the response to ICIs.