[Superficial and infiltrating bladder tumor. Epidemiologic differences in a study of incident cases]

An attempt has been made to identify the epidemiological factors associated with occurrence of biologically aggressive vesical tumours. In the Autonomous Community of La Rioja, a survey was conducted between 1975-1991 of incidental vesical tumours, recording in each case the patient's sex, age and occupation. It was found that the male sex, the sixth decade of life and being a farmer were associated to a higher incidence of vesical tumour. All this data was subsequently analyzed, segregating surface from infiltrant tumours depending on whether they affected (infiltrant) or not affected (surface) the vesical muscle layer. After both groups had been compared, no statistically significant differences were identified with regard to age, sex or occupation. The epidemiological factors associated to the occurrence of vesical tumours have no influence on its biological aggressiveness at the time of diagnosis.