High-grade UTUC has a higher tendency for genomic alteration in fibroblast growth factor receptor 3 (FGFR3), Hras proto-oncogene, GTPase (HRAS), and cyclin-dependent kinase inhibitor 2B (CDKN2B), whereas high-grade UBUC is more frequently altered in tumor protein p53 (TP53), AT-rich interaction domain 1A (ARID1A), RB transcriptional corepressor 1 (RB1), and erb-b2 receptor tyrosine kinase 2 (ERBB2) (19, 20). Here, RB1 is linked to renal pelvis/ureter urothelial carcinoma.