Objectives: We examined the incidence trends of bladder and kidney cancers using a population-based cancer registration data.
Methods: Age-standardized incidence rates were analyzed using data from the Shanghai Cancer Registry during 1973 to 2005. Annual percentage changes and 95% confidence intervals were calculated to evaluate the incidence changes. Age-period-cohort analysis was further implemented to assess the contributions of age, period and cohort effects to the trends using the intrinsic estimator method.
Results: In total, 12,676 bladder and 5,811 kidney cancer patients were registered in urban Shanghai. The age-standardized rates of bladder cancer in males increased from 6.39 to 7.66 per 100,000, or 0.62% per year, whereas the rates in females increased from 1.95 to 2.09 per 100,000, or 0.33% per year. For kidney cancer, the age-standardized rates in males increased from 1.20 to 5.64 per 100,000, or 6.98% per year. Similarly in females, the rates increased from 0.85 to 3.33 per 100,000, or 5.93% per year. Age-period-cohort analysis showed increasing curves of age and period effects but generally decreasing cohort effects for bladder and kidney cancers.
Conclusions: Our results show increasing incidence trends of bladder and kidney cancers in Chinese men and women, especially for kidney cancer.