Radiotherapy-related Neurological Complications in Nasopharyngeal Carcinoma Patients: A Multi-center Epidemiological Study in Southern China
Menée en Chine à partir de données portant sur 22 302 patients atteints d'un carcinome du rhinopharynx traité entre 2003 et 2017 (durée de suivi : 101 714 personnes-années), cette étude analyse les facteurs associés à la survenue de complications neurologiques induites par la radiothérapie
Background: We aim at describing the incidence, potential predisposing factors, and progression of major radiotherapy-related neurological complications (RRNCs) in nasopharyngeal carcinoma (NPC)-endemic regions, especially southern China. Methods: We performed a multi-center longitudinal retrospective study with clinical follow-ups in 22302 post-radiotherapy NPC patients between January 2003 and June 2017 covering 3 major residential areas. Epidemiology, potential predisposing/protective factors, clinicopathological progression, and survival conditions of each RRNC were separately recorded and analyzed based on their related clinical, radiological, and laboratory parameters. Results: 949 new cases of RRNCs occurred among the 22302 post-radiotherapy NPC patients during 101,714 person years' follow-up, which is equal to an incidence density rate of 9.3 new cases per 1000 person year. Radiation-induced cranial nerve palsy showed the highest incidence (2.68%, 597/22302) with the earliest onset (median latency, 4.45 years) as well. Patients benefited from intensity-modulated radiotherapy (IMRT) over conventional radiotherapy (CRT) in both overall survival (median survival 13.2 years for IMRT vs. 8.3 years for CRT) and RRNCs-free survival (except for epilepsy and cranial nerve palsy). Causes of death varied substantially between patients with or without RRNCs. Conclusions: Our study indicates a non-negligible incidence of RRNC spectrum in southern China in the past ten years. IMRT is one of the most significant protectors against development and progression of RRNCs. Impact: Our findings support the hypothesis that NPC patients with preexisting predispositions would receive long-term benefits from IMRT and other dose-related modulations (like hyper-fractionation and dose conformation).