Treatment outcomes and late complications of 849 patients with nasopharyngeal carcinoma treated with radiotherapy alone

Purpose: The objective of this study was to describe the treatment outcomes and treatment-related complications of nasopharyngeal carcinoma (NPC) patients treated with radiotherapy alone. Methods and Materials: Retrospective analysis was performed on 849 consecutive NPC patients treated between 1983 and 1998 in our institution. Potentially significant patient-related and treatment-related variables were analyzed. Radiation-related complications were recorded. Results: The 5-year overall and disease-free survival rates of these patients were 59% and 52%, respectively. Advanced parapharyngeal space (PPS) invasion showed stronger prognostic value than PPS invasion. Multiple neck lymph node (LN) involvement was demonstrated to be one of the most powerful independent prognostic factors among all LN-related parameters. External beam radiation dose more than 72 Gy was associated with significantly higher incidence of hearing impairment, trismus, and temporal lobe necrosis. Conclusions: We recommend that the extent of PPS should be clarified and stratified. Multiple neck LN involvement could be integrated into the N-classification in further revisions of the American Joint Committee on Cancer stage. Boost irradiation is not suggested for node-negative necks. For node-positive necks, boost irradiation is indicated and a longer interval between initial and boost irradiation would reduce the incidence of neck fibrosis without compromising the neck control rate.