MDM2 and renal pelvis/ureter urothelial carcinoma: Fujii et al. showed in 2021 that UTUC can be divided into five DNA-based molecular subtypes (i.e., hypermutated, TP53/MDM2, RAS, FGFR3, and triple negative), and the TP53/MDM2 mutational subtype is associated with high grade, invasiveness, and a poor prognosis in UTUC (Fujii et al. 2021).