Head and neck cancer: hypofractionated adjuvant radiation therapy

Abstract

INTRODUCTION: Effect of adiuvant radiation therapy (RT) on oncologic outcomes is well-known and confirmed by different trials. Optimal time to start RT is 6–8 weeks after surgery. Increasing duration of RT delay beyond that interval leads to decrease in overall survival (OS) and makes loco-regional recurrence (LRC) more probable. However, more than 50% patients do not receive adjuvant treatment in time (Mitra S. et al., 2022). Overall treatment time (77–100 days) is another factor that influences effectiveness of adjuvant RT. In order to keep within that time limits non-conventional regimens of RT can be used.OBJECTIVE: To test safety and feasibility of hypofractionated adjuvant RT in patients with locally advanced squamous cell carcinoma of oral cavity and oropharynx.MATERIALS AND METHODS: Patients with stage III–IV squamous cell carcinoma of oral cavity and oropharynx (n=11) who underwent surgery and have to recieve adjuvant RT in 8 weeks and more after surgery are included. Dose was delivered using Volumetric Modulated Arc Therapy (VMAT) and simultaneous integrated boost.RESULTS: Patients (n=11) completed RT successfully. Surgery-to-RT interval ranges between 9 and 15 weeks. Dose per fraction on high-risk-CTV varies between 2,5 and 2,75 Gy. Acute side-effects (oral mucositis grade II) presented after 27–32 Gy (11–13 fractions) in 9 patient out of 11 and reached maximum (oral mucositis grade III, radiation dermatitis grade II) at the end of the treatment.CONCLUSIONS: Hypofractionated adjuvant RT (VMAT) can be safely used in patients with locally advanced squamous cell carcinoma of oral cavity and oropharynx and local acute toxicity can be controlled.