The best proper doses of IFRT in combined modality treatments (CMT) for localized DLBCL is still undetermined. Existing treatment guidelines recommend 40Gy or above as the standard treatment dosage. However, there were large-scaled clinical trials implying smaller doses such as 30Gy may be equivalent effective. Lowering radiation doses can decrease treatment toxicities and radiotherapy-induced diseases, which has been conformed by HD13 study for Hodgkin's Lymphoma. It may even retain the truth when modern era radiation techniques are involved and especially in patients achieving CR after chemotherapy. A comprehensive, prospective dose-comparing study is needed.
