Gender difference in radiotherapy-induced carotid stenosis

Abstract

Radiotherapy (RT) is often the first choice of treatment for cancer of the larynx. Studies have shown that the incidence of carotid stenosis (CS) after radiotherapy of laryngeal cancer is increasing, and that gender difference in radiotherapy-induced side effects exist. Thus, we examined the gender difference in the incidence of CS and the impact of microinflammatory factors after radiotherapy. We reported this study on patients who received radiotherapy as part of the treatment for laryngeal cancer in the Jilin Province in China. One hundred sixty-four males and 152 females were treated with radiotherapy between 2006 and 2016. The carotid diameter was determined by measuring carotid intima-media thickness in the common, external and internal carotid artery. Microinflammatory conditions were assessed by measuring the level of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). Other studied risk factors included age, treatment modalities, radiation dose and energy, the height of the radiation field, and the follow-up time. CS was detected in 161 (50.9%) of the 316 patients. Carotid stenosis was mainly clinically unsuspected, two patients had anamnesis of unconsciousness. Importantly, fewer women (36.1%) had CS than men (64.6%) (p=0.004). Furthermore, male patients showed higher serum levels of hs-CRP, IL-6, and TNF-α. Taken together, our study suggested that women underoing radiotherapy of laryngeal cancer are less likely to have CS than men. Therefore, routine assessment after irradiation of laryngeal cancer seems necessary for clinical detection of asymptomatic CS, particularly in male patients.