Radiation-Induced Trismus Triggers Jaw Osteoradionecrosis Development in Locally Advanced Nasopharyngeal Cancer Patients Undergoing Concurrent Chemoradiotherapy

Abstract

To investigate whether radiation-induced trismus (RIT) influences the rates of osteoradionecrosis of the jaw (ORNJ) in patients with locally advanced nasopharyngeal carcinoma (LA-NPC) who are undergoing definitive concurrent chemoradiotherapy (C-CRT). This retrospective study analyzed data from 295 LA-NPC patients who underwent C-CRT and received oral and periodontal examinations before and after C-CRT. The study's primary objective was to determine any definitive associations between RIT and ORNJ rates. Forty-six (15.6%) and 23 (7.8%) patients were diagnosed with RIT and ORNJ, respectively. ORNJ was significantly more prevalent among patients with RIT (16/46; 34.8%) compared to those without RIT (7/249; 2.8%) (P0.001). The median interval between the diagnoses of RIT and ORNJ was 9.5 months (range: 1-26 months). Notably, 15 out of 16 (93.7%) cases of ORNJ were diagnosed > 1 month after the diagnosis of RIT. Spearman's correlation analysis demonstrated a strong and statistically significant relationship between the presence of RIT and the subsequent development of ORNJ (rs = 0.714, p < 0.001). The results of the multivariate analysis indicated that a previous diagnosis of RIT was a significant and independent predictor of an increased rate of ORNJ development. Our study's findings demonstrated that RIT may be a significant risk factor for the increased prevalence rates of subsequently developed ORNJ in patients with LA-NPC treated with C-CRT, emphasizing the pressing need for effective RIT prevention strategies to reduce ORNJ rates in this patient population.