FGFR3 may be a regulator of the UTUC immune environment by weakening interferon γ (IFNG) signalling, and it is suggested that interferon response genes may be upregulated by inhibiting FGFR3 or PD-1/PD-L1, thereby reversing T cell depletion in UTUC and remodelling the immune environment, which provides a theoretical basis for targeted therapy. The gene discussed is PDCD1; the disease is renal pelvis/ureter urothelial carcinoma.