The best arm of the RICOVER-@ trial ( @R-CHOP-@ +@ R -LSB- R-CHOP administered once every @ weeks plus two additional applications of rituximab -RSB- plus involved-field RT -LSB- @ Gy -RSB- to sites of initial bulky -LSB- @ cm -RSB- disease and extralymphatic involvement ) was compared with a cohort receiving the same immunochemotherapy but without RT in an amendment to the RICOVER-@ trial ( RICOVER-noRTh ) in a prospective fashion .