Randomized trial on external radiation therapy alone versus external radiation therapy followed by brachytherapy in early stage nasopharyngeal carcinoma with a long term result

Objective To compare local control and toxicity in patients treated with external beam radiotherapy followed by intracavitary brachytherapy (BT) versus external beam radiotherapy alone (RT) for locally early stage nasopharyngeal carcinoma (NPC). Methods From 1990 to 1997, 126 NPC patients staged T1 and T2 by 1992 Fuzhou Staging System (oropharynx, carotid sheath and soft tissue around cervical vertebral involvement excluded) were randomized into RT alone and RT followed BT groups. The two groups were comparable in age, gender, stage and pathology. The median follow-up was 112 months. T1 patients were randomized before the treatment into RT alone group of 66-70?Gy and RT plus BT with the dose of 56?Gy plus 10-16?Gy BT boost to the nasopharynx. For T2 patients, if MRI or CT showed no residual lesion in parapharyngeal space after 50?Gy, they were randomized into RT alone (median dose: 72?Gy) or RT of 66?Gy followed by 8-24?Gy BT boost (1-3 fractions over 1-3 weeks). Results In RT group, 8 patients (13.1%) failed in primary site during the follow-up period, 7 (11%) in BT group. The 5-year local control rates was 86% for RT group and 88% for BT group (P=0.47). The 5-year overall survival rates were 83% and 84% (P=0.84), respectively. Ten patients (18%) in RT group (4 of grade Ⅰ, 6 of grade Ⅱ) and 7 patients (11%) in BT group (4 of grade Ⅰ, 3 of grade Ⅱ, P=0.31) developed radiation induced encephalopathy. The incidence of trismus was much lower in BT group than in RT group (26% versus 10%, P=0.02). No soft palate perforation or sphenoid necrosis were observed. Conclusion Compared to conventional external beam radiaotherapy, planned irradiation plus intracavitary brachytherapy not only can achieve similar local control and survival rates for locally early stage nasopharyngeal carcinoma, but also decrease irradiation dose and the trismus incidence.