Aim: To identify all incident cases of bladder cancer in the county of Vallès Occidental (Spain), describe their histopathological characteristics, and make comparisons with other Spanish and European areas.
Method: The study was carried out from the Corporació Parc Taulí (Sabadell). All new cases of bladder cancer in residents of the county Vallès Occidental, a highly industrialised area of Catalonia (Spain), were included between 1992 and 1994. Incidence rates of bladder cancer were adjusted and were compared with adjusted incidence rates reported by registries in other Spanish and European countries.
Results: 485 new cases were identified. Transitional cell carcinomas predominated (95.5%). The majority of tumours were diagnosed in their initial stages, 75.9% being superficial and 62.6% well to moderately differentiated. Bladder cancer was more common in men than in women, but women presented tumours of worse prognosis. The mean age at diagnosis was also higher in women than men (71 vs. 66 years, p = 0.03). The adjusted incidence rate in men (52.2 cases/100,000) was among the highest of the observed areas, whereas for women (5.4 cases/100,000) was relatively low.
Conclusions: The incidence of bladder cancer among men in Vallès Occidental is among the highest in Europe, and intermediate for women. The high male/female ratio seen in all Spanish areas could be attributed to the fact that women in Spain have been less exposed than men to the risk factors, or their exposure occurred more recently.