Trends of cutaneous squamous cell carcinoma in the Netherlands: Increased incidence rates, but stable relative survival and mortality 1989-2008

Background: Incidence rates of cutaneous squamous cell carcinoma (SCC) are increasing in many countries, though detailed information is scarce. Objectives: To describe detailed trends in incidence rates, relative survival and estimate mortality rates of SCC in the Netherlands. Methods: Information on newly diagnosed SCC patients between 1989 and 2008 was obtained from the Netherlands Cancer Registry (NCR). Information of non-melanoma skin cancer (NMSC) mortality was obtained from Statistics Netherlands. European Standardised Rates (ESR) and Estimated Annual Percentage Change (EAPC) were calculated. Incidence rates were fitted to two different models and predicted by the best fitted model. Cohort-based and multivariate survival analyses were performed to assess changes over time. Results: The ESR increased from 22.2 to 35.4 per 100,000 inhabitants for males and from 7.8 to 20.5 for females. The EAPC was 6.9% (95% confidence interval: 5.8-8.7) for males and 9.2% (95% CI: 7.5-11.0) for females. Incidence rates increased for all body sites, except for the lips, where a decreasing trend for males was observed. The predicted ESR in 2020 is 46.9 per 100,000 inhabitants for males and 28.7 for females. The 5-year relative survival rate was 92.0% (95% CI: 91.3-92.8) for males and 94.9% (95% CI: 94.0-95.7) for females and remained stable over time. Overall relative survival was better for females, but females with advanced disease had a 30.4 relative excess risk of dying compared to those in stage I. This difference was 9.9 for men. The estimated mortality rate decreased with -1.9% (95% CI: -3.1% to -0.7%) annually. Conclusions: Incidence rates of SCC increased rapidly. Relative survival was high, as most SCCs were diagnosed in stage I. Nevertheless, the number of newly diagnosed patients may exceed 11,000 by 2020, emphasising the need to improve methods to prevent skin cancer.