Postirradiation sinus mucosa disease in nasopharyngeal carcinoma patients

OBJECTIVES/HYPOTHESIS: We sought to determine the incidence, progression, and risk factors for postirradiation sinus mucosa diseases (SMD) incidentally found on follow-up magnetic resonance images (MRIs) in nasopharyngeal carcinoma (NPC) patients. STUDY DESIGN: Retrospective. METHODS: The medical records, pre- and postradiotherapy (RT) MRIs were reviewed in NPC patients. Lund-Mackay system for staging of rhinosinusitis (Lund score) was used as a tool for investigation. RESULTS: One hundred twelve NPC patients (77 males and 35 females) were recruited in this study. The distribution of tumor staging in these patients were 39 (34.8%) patients in T1, 23(20.5%) in T2, 31(27.7%) in T3, and 19 (17.0%) in T4 by MRI staging before RT. In these 62 patients with normal sinus ventilation before RT, 42 (67.7%) patients returned to having SMDs 3 months after RT. The maxillary, anterior ethmoid, and posterior ethmoid sinuses were most readily affected. In patients with SMDs at 3 months postRT, advanced tumor stage (P = .013) and smoking habit (P = .047) were the two factors that significantly influence Lund score. When comparing Lund score with different times after radiation therapy, a trend of decrease in Lund score could be noted from 3 months to 3 years after irradiation. CONCLUSIONS: The incidence and severity of SMD was found to be highest at 3 months postRT and decreased gradually with time. Conservative management with clinical symptom correlation should be attempted first in these patients. In these NPC patients, advanced tumor stage and smoking habit would predispose them to SMD development.