Risk factors of post-irradiation carotid blowout syndrome in patients with nasopharyngeal carcinoma

Purpose: Carotid blowout syndrome (CBS) is a severe complication of radiotherapy in patients with nasopharyngeal carcinoma (NPC). This study is aimed at analyzing risk factors of post-irradiation CBS in patients with NPC. Methods: We retrospectively analyzed 660 patients with NPC between 2006 and 2019. The patients were divided into those with and without CBS, and their characteristics and outcomes were evaluated. Independent predictors of CBS were determined by multivariate logistic regression analysis. Results: We identified 17 NPC patients with CBS in our study. In multivariate logistic regression analysis, lower body mass index (BMI) (P = 0.018), tumor encasement (P = 0.039), local recurrence (P = 0.006), and skull base osteoradionecrosis (P < 0.001) were independent predictors of CBS, and a predictive equation model was established. Log-rank test revealed that patients with low BMI, tumor encasement of carotid vessels, local recurrence, and skull base osteoradionecrosis all exhibited shorter CBS-free time (all P < 0.001). Conclusion: We demonstrated that low BMI, tumor encasement, local recurrence, and skull base osteoradionecrosis were independent predictors for CBS in NPC patients. Physicians can use these factors for the early detection and prevention of CBS.