In general, we found that PD-L2 was expressed on both TCs and ICs in DLBCL by immunohistochemistry, patients with PD-L2-positive on TCs had significantly longer PFS and OS, and patients with PD-L2-positive on TCs and TME who received the CHOP regimen resulted in higher ORR. The gene discussed is PDCD1LG2; the disease is diffuse large B-cell lymphoma.