Therefore , we started the randomized EORTC/LYSA/FIL Intergroup H10 trial evaluating whether involved-node radiotherapy ( IN-RT ) could be omitted without compromising progression-free survival in patients attaining a negative early PET scan after two cycles of ABVD ( doxorubicin , bleomycin , vinblastine , and dacarbazine ) as compared with standard combined-modality treatment .