[Efficacy of accelerated fractionation versus conventional fractionation for nasopharyngeal carcinoma].

BACKGROUND & OBJECTIVE Radiotherapy is an important treatment for nasopharyngeal carcinoma (NPC). Timing of radiotherapy has attracted more attention nowadays. This study was to assess the efficacy of accelerated fractionation (six fractions per week) versus conventional fractionation (five fractions per week) for NPC, thus to improve treatment efficacy without increasing complications. METHODS Three hundred and thirty-nine NPC patients treated with radiotherapy were retrospectively analyzed, including 181 patients in the accelerated fractionation group and 158 patients in the conventional fraction group. All patients were radiated using a 6MV X-ray beam, 2 Gy per fraction, once a day. A total dose (TD) of 64-72 Gy, divided into 32-36 fractions, were irradiated to the nasopharyngeal regionû a TD of 62-68 Gy, divided into 31-34 fractions, were irradiated to the cervical region. The TD of prophylaxsis was 50-52 Gy, divided into 25-26 fractions. All N3 patients received adjunct chemotherapy. RESULTS The 1-, 3-and 5-year local control and survival rates of the accelerated fractionation group and the conventional fractionation group were (98.9% and 98.3%) vs. (98.1% and 96.8%), (95.5% and 91.2%) vs. (88.2% and 80.4%), (87.3% and 69.6%) vs. (76.6% and 51.3%), respectively. The 3-and 5-year local control and overall survival rates between the two groups were significantly different (P=0.079 and P=0.0011 vs. P=0.09 and P=0.0001). The incidence of acute reactions was higher in the accelerated fractionation group than in the conventional fractionation groupû but the incidence of delayed reactions between the two groups was not significantly different. The disease-free survival was significantly longer in the accelerated fractionation group than in the conventional fractionation group (P=0.002). CONCLUSION Compared with conventional fractionation, accelerated fractionation significantly improves the 3-and 5-year local control and overall survival rates, as well as the disease-free rate for NPC patients without increasing delayed toxicity.