Arm 1: Radiotherapy ± chemotherapy (RCT)
tumor, tumors, Tumor, skin overdosage
TUMOR, TUMORS, TUMOR
Volumetric Modulated Arc Therapy (VMAT) with simultaneous Integrated Boost (SIB) will be used for all patients in this study.For all cT1-T2N0 tumors, patients will be treated with moderately accelerated radiotherapy alone. Primary Gross Tumor Volume (GTVp) will be delineated according to the clinical examination and the available imaging. A 10 and a 5 mm margins (adapted to anatomical barriers) will be added to generate the Primary Clinical Target Volumes (CTVp) treated at prophylactic and radical (or therapeutic) doses, respectively (according to the current guidelines [The therapeutic CTVp includes the tumor area and the high-risk location. It will be irradiated up to a total dose of 69 Gy in 30 fractions (2,3 Gy/fraction, 5 fractions a week during 6 weeks) or 70 Gy in 35 fractions (2,0 Gy/fraction, 6 fractions a week during 6 weeks).The prophylactic CTVp includes the elective mucosa. It will be irradiated up to a total dose of 54 Gy in 30 fractions (1,8 Gy/fraction, 5 fractions a week during 6 weeks) or 54,25 Gy in 35 fractions (1,55 Gy/fraction, 6 fractions a week during 6 weeks).Elective CTVn must be selected and delineated according to the international recommendations and treated at prophylactic dose [All CTVs will be expanded by an isotropic 3–5 mm margin to generate the related Planning Target Volume (PTV). Margin may be cropped at level of skin for correct optimization and avoiding skin overdosage.For all cT1-T2 N1 tumors, patients will be treated with concurrent radio-chemotherapy [In the case of concomitant chemotherapy, the selection, delineation and prescription will follow the same principles as stated above, except that.Nodal Gross Tumor Volume (GTVn) will be delineated according to the clinical examination and available imaging. A 5 mm margin adapted to anatomical barriers will be added to generate the nodal Clinical Target Volume treated (CTVn), to be treated at therapeutic dose.Only normo-fractionated schedule may be used but may be accelerated at the discretion of the center by use of 6 fractions a week.The standard chemotherapy regimen is the Cisplatin 100 mg/m