Dose volume histogram constraints in patients with head and neck cancer treated with surgery and adjuvant HDR brachytherapy: A proposal of the head and neck and skin GEC ESTRO Working group

Highlights: • This study aimed to identify DVH Constraints of Osteonecrosis & SoftTissue Necrosis. • The study evaluated 227 patients treated with surgery & HDR brachytherapy (+/- EBRT). • Soft Tissue Necrosis correlated with CTVsize>15 cm³and Total EQD2-DVH TV₁₀₀> 87Gy. • Osteoradionecrosis correlated with Physical Dose to Mandible 2cm³ >61 Gy. The Head and Neck and Skin (HNS) Working group of the GEC-ESTRO acknowledges the lack of widely accepted Dose Volume Histogram (DVH) constraints in adjuvant head and neck brachytherapy and issues recommendations to minimize mandibular Osteoradionecrosis (ORN) and Soft Tissue Necrosis (STN).