Trial Evaluating the Tolerance and Safety of Durvalumab - RT Combination for Treatment in SCCHN

This study evaluate the regional (neck) nodal control of durvalumab in combination with RT restricted to the primary tumor and the immediately adjacent nodal level (i.e. without prophylactic neck irradiation) in N0 patients with SCCHN.

There is a strong rationale for testing this new paradigm of RT for SCCHN without prophylactic neck irradiation, being replaced by immune stimulation via the combination of RT and Programmed Death-1 (PD-L1) inhibition with durvalumab, due to: * The unmet medical need for new treatments, better tolerated and " as " or " more " effective than the current Standard Of Care (SOC) * The need to decrease radiation-induced toxicity, especially in fragile patients * The added toxicity due to elective nodal irradiation * The strong rationale to combine RT and PD-L1 inhibition * The potential immune suppressive effect of large field prophylactic neck irradiation It is hypothesized this innovative concept to be safe in the context of this study for the following reasons: * The rate of relapse in the neck is expected to be low in Magnetic Resonnance Imaging (MRI) \& PET-CT N0 neck * A non-irradiated neck can be easily monitored, clinically and by imaging * Most of the potential relapses in the neck are expected to be salvaged by surgery and/or RT * The preventive irradiation of N0 regions is not anymore performed for others lymphophilic cancers (lymphoma, Non-Small Cell Lung Cancer (NSCLC)). The combination of durvalumab with RT restricted to the primary tumor site and immediate adjacent nodal area will achieve a similarly regional (nodal) control rate than standard RT including large prophylactic neck irradiation (regional recurrence \< 10 %. This study will include patients with early (T1-T2 N0) or locally advanced SCCHN (T3-4 N0), histologically proven who had not received previous treatment for this setting. The study is designed with the primary objective of demonstrating that RT without large prophylactic irradiation in combination with durvalumab is effective in terms of regional control. All patients will be followed until death or at least 36 months.