CDKN2A and neoplasm: The accumulated evidence suggests that UBCs develop along two distinct pathways—papillary low-grade tumours developing from intermediate cells and non-papillary high-grade tumours developing from basal urothelial cells [12, 13]; notwithstanding, early events appear common to both pathways (e.g. TERT promotor mutations, loss of CDKN2A) [14, 15].