Radiotherapy (RT), surgery and chemotherapy (CT) are treatments for head and neck cancers, used alone or in combination. Conformal RT with Intensity Modulation (IMRT) is currently the reference technique. IMRT requires a precise definition of the target volumes to be treated and the anatomical structures to be protected from irradiation. Most studies of head and neck cancers published in the literature demonstrate the variability in the contouring of the target volumes between radiotherapists. This may have an impact on dosimetry. To date, no studies have evaluated the impact of the ENT surgeon's evaluation in volumes contouring. The aim of this study is to compare the volumes determined by the radiotherapists alone and those determined jointly by the radiotherapists and the ENT surgeon.