Bladder cancer is the second most com-mon urological cancer according to statistics and it is an important cause of mortality and morbidity. The median age of incidence of bladder cancer have been reported as 69 in men and 71 in women. Herein we presented 3 patients younger than 20 years old with tran-sitional cell carcinoma of bladder (superficial, low grade according to the 2004 WHO/ISUP classification system) and discussed these pa-tients in the light of the literature. 
Despite the fact that transitional cell car-cinoma of bladder is rare under the age of 20, patients with hematuria and risk factors for bladder cancer should be examined for blad-der cancer regardless of age.
Keywords: Bladder tumor; young; occu-pational exposure; smoking
                                        
                                        
                                     
                                    
                                        
                                            Abstract
                                        
                                        Bladder cancer is the second most com-mon urological cancer according to statistics and it is an important cause of mortality and morbidity. The median age of incidence of bladder cancer have been reported as 69 in men and 71 in women. Herein we presented 3 patients younger than 20 years old with tran-sitional cell carcinoma of bladder (superficial, low grade according to the 2004 WHO/ISUP classification system) and discussed these pa-tients in the light of the literature. 
Despite the fact that transitional cell car-cinoma of bladder is rare under the age of 20, patients with hematuria and risk factors for bladder cancer should be examined for blad-der cancer regardless of age.
Keywords: Bladder tumor; young; occu-pational exposure; smoking