Rising trends in the incidence of and mortality from cutaneous melanoma in the Netherlands: A Northwest to Southeast gradient?

The aim of this study was to determine characteristics of the trends in incidence of and mortality from cutaneous malignant melanoma in The Netherlands. We used incidence data from the Netherlands Cancer Registry since 1989 and the causes of death registry of Statistics Netherlands since 1950. Data were age-adjusted and age-specific rates were calculated. Age-period-cohort modelling was applied to the mortality data. Between 1989 and 1998, age-adjusted incidence rates increased, mainly among those aged 45 years and older. Incidence rates were highest in the North-West and lowest in the South-East. Mortality rates increased in all age-categories, but more so among males than females. For women, an age-period model fitted the data, with decreasing relative risks after 1972. Age-period-cohort models were needed for males. The most likely explanation for the higher incidence is increasing intermittent over-exposure to ultraviolet (UV) radiation. The regional differences in melanoma incidence rates would correspond with host characteristics opportunities for and recreational exposure. Melanomas were detected at earlier stages in females, possibly explaining the flattening out of the female mortality rates.