Advances in molecular genetics of early-stage urothelial carcinoma

Bladder cancer is the most common malignancy involving the urinary system. Urothelial (previously known as transitional cell) carcinoma is the predominant histologic type of bladder cancer especially in developed countries (1). Taking into account both histopathological and molecular features, this ‘two-pathway’ model proposes that papillary non-muscle-invasive bladder cancer (NMIBC) develops via epithelial hyperplasia and recruitment of a branching vasculature, while MIBC derives through flat dysplasia and carcinoma in situ (CIS).