1505-PUB: Impact of Diabetes on Radiotherapy-Related Infection

Abstract

Background and Purpose: Poor perioperative glucose control in diabetes patients is associated with infectious adverse effects (AEs) . Radical radiotherapy (RT) for head and neck (H&N) cancer extensively destroys skin and the mucosa barrier function, and can be as invasive as surgery. In this study, the risk of radiation-induced acute infectious AEs was investigated in a cohort of diabetic patients given RT for H&N cancer. Materials and Methods: Acute AEs associated with RT in diabetic patients treated between January 2017 and July 2021 at three institutions were retrospectively analyzed. Patients were included if they met the following criteria: confirmed diagnosis of type 1 or 2 diabetes mellitus, age > years, stable on glucose-lowering therapy before starting RT, and had undergone RT for pathologically proven malignancies. The endpoint was the rate of acute infectious AEs graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events v5.0. Results: A total of 216 patients were eligible for the present study (median follow-up, 15.6 months; range, 1.3-33.3 months; median age, 72 years; range, 33-90 years) . The median glycated hemoglobin (A1c) value at the start of RT was 7.4% (range, 4.1%-12.7%) . Grade ≥ 3 acute infectious AEs that occurred in 31 (14.4%) patients included mucosal infection, pneumonia, and sepsis. Five patients died due to infectious AEs that developed during or after RT. Concurrent chemoradiotherapy (CCRT) (OR, 2.0; 95%CI, 0.9-4.6; P = 0.08) tended to be a predictor of severe infectious AEs. The frequency of glucose control by diabetologists during CCRT was significantly lower than during RT alone (P = 0.001) . Conclusions: The incidence of severe infectious AEs was high in the present cohort of irradiated diabetic patients with H&N cancer compared with historical data. Patients with CCRT had a higher risk of AEs, which should be considered before irradiation. Therapeutic intervention for glucose control by diabetologists during CCRT may lead to fewer severe infectious AEs. Disclosure K. Ito: None.