The FLYER trial (17) did not investigate RT in either of its arms, but established the noninferiority of R-CHOP ×4—R ×2 vs. R-CHOP ×6 in patients with limited-stage, non-bulky, low-risk DLBCL, and reinforced a platform for omission of RT compared to historical R-CHOP ×3 + RT. This evidence concerns the gene DDIT3 and diffuse large B-cell lymphoma.