Experience of long-term management for osteoradionecrosis of the maxilla after carbon ion radiotherapy

Purpose: The aim of this study was to evaluate the incident of maxillary osteoradionecrosis (ORN) in patients who underwent carbon ion radiotherapy (CIRT) for head and neck cancer. We report the experience of long-term management for ORN especially required surgical intervention for grade 3 morbidity. Materials and methods: From April 1997 to April 2006, 239 patients with the head and neck cancers were treated with CIRT with a dose of 57.6 GyE per 16 fractions. Patients whose alveolar process and palatine process of maxilla had been irradiated more than 10% of the prescribed dose were selected. We exclude the cases of after operation therapy and after radiation therapy. For this study, we employed the criteria for adverse events presented in Common Terminology Criteria for Adverse Events (CTCAE) v4.0 released by the U.S. National Cancer Institute. Results: Sixty-seven patients were enrolled in this study (Table 1). Of the 67 patients, 33 patients (49.3%) developed ORN. Sixteen patients (23.9%) received no treatment, 13 patients (19.4%) with exposed sequestrum received conservative therapy. All of grade 2 patients could control clinical symptoms treated with analgesics and oral care. Four patients (6.0%) with severe symptoms were undergone sequestrectomy (Table 2). After sequestrectomy, all of four patients showed no signs of sequestrum re-exposure or symptom exacerbation during the average follow-up period of 36.7 months. In addition, masticatory function was maintained using dento-maxillary prosthesis in all cases. Conclusions: Although 33 patients developed ORN, only 4 patients needed the surgical treatment. However, we could control the clinical symptoms and improved the QOL for the four patients after surgical intervention.