RecruitingPhase 3Radiation therapyPET Guided Dose Reduction for InvOlved Site Radiotherapy In Early sTage Unfavourable Hodgkin LymphomaThe final analysis of GHSG HD11 study (not PET driven) showed that 30 Gy IFRT still remains the standard dose after 4 ABVD. Early PET negativity might allow safe radiation de-escalation in patients achieving a metabolic complete response after 2 ABVD. The aim of Priority trial is to explore whether radiotherapy could be safely deescalated to 20 Gy without loss of efficacy in patients treated with four cycles of ABVD who achieved complete metabolic response after the first two cycles.