Clinical outcomes and patterns of disease recurrence following intensity modulated proton therapy for oropharyngeal squamous carcinoma : results from a single institution prospective study
Mené sur 50 patients atteints d'un carcinome épidermoïde de l'œsophage traité entre 2011 et 2014 (durée médiane de suivi : 29 mois), cette étude évalue l'efficacité, du point de vue du contrôle de la maladie et des taux actuariels de survie sans progression ou de survie globale à 2 ans, et la toxicité d'une protonthérapie avec modulation d'intensité, puis identifie les formes de récidive
Background : A single institution prospective study was conducted to assess disease control and toxicity of proton therapy for patients with head and neck cancer. Methods : Disease control, toxicity, functional outcomes and patterns of failure for the initial cohort of patients with oropharyngeal squamous carcinoma (OPC) treated with intensity modulated proton therapy (IMPT) were prospectively collected in two registry studies at a single institution. Locoregional failures were analyzed utilizing deformable image registration methodology. Results : Fifty patients with OPC treated from 03/2011 to 07/2014 formed the cohort. Eight-four percent were male, 50% were never smokers, 98% were p16+, 98% had stage III/IV disease, 64% received concurrent and 35% received induction chemotherapy. Forty-four of 45 (98%) tumors tested for p16 were positive. All patients were treated with IMPT (multi-field optimization n=46; single-field optimization n=4). No CTC-AE grade 4/5 toxicities were observed. The most common grade 3 acute and late toxicities observed were acute mucositis and late dysphagia, in 58% and 12%, respectively. Eleven patients had a feeding gastrostomy placed during therapy, but none had a feeding tube at last follow up. With a median follow up of 29 months, 5 patients had disease recurrence: local in 1, local and regional in 1, regional in 2, and distant in 1. The 2-year actuarial overall and progression free survival were 94.5% and 88.6%, respectively. Conclusion : The oncologic, toxicity and functional outcomes following IMPT for OPC are encouraging and provide the basis for ongoing and future clinical studies.