Purpose: A retrospective analysis of risk factors for late neurological toxicity after nasopharyngeal carcinoma radiotherapy.
Patients and methods: Between 1993 and 2004, 239 patients with non metastatic nasopharyngeal carcinoma were treated by radiotherapy associated or not to chemotherapy. Radiotherapy was delivered with two modalities: hyperfractionated for 82 patients and conventional fractionation for 157 patients. We evaluated the impact of tumour stage, age, gender, radiotherapy schedule and chemotherapy on neurological toxicity.
Results: After a mean follow-up of 107 months (35-176 months), 21 patients (8.8%) developed neurological complications, such as temporal necrosis in nine cases, brain stem necrosis in five cases, optics nerve atrophy in two cases and myelitis in one case. Five- and ten-year free of toxicity survival was 95 and 84% respectively. Young patients had greater risk of temporal necrosis, and hyperfractionated radiotherapy was associated with a significantly higher risk of neurological complications (14.6% vs 5.7%, p=0.02). On multivariate analysis, hyperfractionation and age were insignificant.
Conclusion: Late neurological toxicity after radiotherapy for nasopharyngeal carcinoma was rare. Younger age and hyperfractionation were considered as risk factors of neurological toxicity in our study.