ERBB2 and neoplasm: Efforts to decipher the molecular mechanisms involved in bladder carcinogenesis have led to the identification of a number of possible new treatment targets, such as mTOR in patients with TSC1 mutations, epidermal growth factor receptor 2 (HER2)/ERBB2 in HER2-positive tumours, EGFR in basal-like tumours, and fibroblast growth factor receptors, particularly in patients harbouring mutations or gene fusions of FGFR3. 3–5