Chronic rhinosinusitis after radiotherapy in patients with head and neck cancer

Background: Chronic rhinosinusitis (CRS) is a common post-radiotherapy (RT) side effect in patients with nasopharyngeal cancer (NPC). However, whether RT is a risk factor for CRS in patients with other types of head and neck cancer remains unclear. This study investigated the association, if any, between CRS and RT in patients with head and neck cancer. Methods: This retrospective cohort study included the data of patients newly diagnosed as having head and neck cancer between January 1, 2005, and December 31, 2008, from the 2005 Longitudinal Health Insurance Database. Patients were categorized into the following groups according to the treatment regimens received: RT alone (RT-alone), RT combined with other treatments (any-RT), and treatments without RT (no-RT). The outcome was the occurrence of CRS after treatment. Results: Of the 701 patients, 7% experienced CRS within 5 years after initial treatment. Patients were divided into subgroups according to different treatment policies, and the RT-alone group, any-RT group, and no-RT group had 5-year incidence of CRS of 12%, 9.3%, and 4.5%, respectively. Patients in the RT-alone and any-RT groups exhibited an increased risk of CRS compared with patients in the no-RT group (hazard ratio: 6.76 and 2.91; 95% confidence interval: 2.60 to 17.5 and 1.60 to 5.31, respectively). Conclusion: This is the first nationwide population-based cohort study to evaluate the risk of posttreatment CRS in patients with head and neck cancer. Our findings indicate that RT is a major risk factor for CRS. Thus, physicians should consider this potential risk in patients with head and neck cancer after RT.