Multivariate analysis revealed that high CK20 (HR = 3.31, p < 0.001) and low CK5/6 (HR = 0.26, p < 0.001) expression in UTUC specimens were both independent factors for developing IVR as well as pT2 or lower T stage (HR = 1.94, p = 0.007) and a high tumor grade (HR = 1.61, p = 0.032; Table 2). The gene discussed is KRT5; the disease is renal pelvis/ureter urothelial carcinoma.