A phase I/II study evaluating the feasibility and safety of delivering adjuvant hypofractionated radiotherapy in resected oral cavity cancers (HYPO-ART study)

Abstract

Background and purpose: To evaluate the tolerability and efficacy of adjuvant Hypofractionated radiotherapy in resected oral cavity cancer patients. Materials and methods: Post-operative oral cavity cancer patients with indications for adjuvant (chemo) radiotherapy were enrolled. T3/T4 disease, positive lymph nodes(s), lympho-vascular invasion, and/or perineural invasion were considered intermediate risk factors for which a radiation dose of 50Gy over four weeks was delivered. Extra-nodal extension and/or positive margins were considered high-risk factors for which a radiation dose of 62.5Gy over five weeks was delivered. The primary end-point was the incidence of acute radiation-induced toxicities. Secondary endpoints were locoregional control and overall survival. Results: 38 patients were enrolled in the trial and completed planned radiotherapy treatment. No grade 4 toxicity was observed. Acute grade 3 toxicity included oral mucositis in 60.5 % of patients and dysphagia in 18.3 % of patients. 71 % of patients required nasogastric tube placement and 50 % needed day-care support. At a median follow-up of 20.35 months, 57.9 % were alive with no evidence of disease, and 31.6 % of patients had a loco-regional recurrence. Loco-regional control and overall survival at one year were 68 % and 84 %; at two years, they were 59 % and 59 %, respectively. Conclusions: Moderately hypofractionated radiotherapy is well tolerated and can safely be delivered for resected oral cavity tumors with optimal supportive care while maintaining similar oncological outcomes compared to conventional fractionation.

Keywords

• Hypofractionation
• Radiotherapy
• Head and neck cancer
• Oral cavity cancer