Increase in and stabilization of incidence and mortality of primary cutaneous malignant melanoma in Western Netherlands, 1980-95.

In summer 1989, a skin cancer campaign was organized in the coastal area of western Netherlands. In order to assess the impact of this and future campaigns on detection rates for melanomas of various thicknesses, a frame of reference for the epidemiology of cutaneous melanoma was established. We performed a retrospective investigation of all melanomas diagnosed in this region in the period 1980-95. A total of 3705 (2967 invasive and 738 in situ melanomas) cases was analysed. During the 1980s the age-adjusted incidence of invasive melanoma steadily increased (from five in 100,000 to 11 in 100,000 for men and from nine in 100,000 to 14 in 100,000 for women). Since 1988/89 the rate has remained stable for men and has increased only slightly among women. Detection rates for in situ melanomas followed the same pattern. Mortality rates remained largely unchanged for both sexes (European standard rates are about 2.6 in 100,000 for men and 2.2 in 100,000 for women). The median Breslow thickness decreased from 1.2 to 1.1 mm for men and from 1.1 to 0.8 mm for women. A marked increase occurred in the proportion of thin melanomas in comparison with intermediate and thick tumours, particularly among women. The female/male ratio declined in the period studied from 2.0 to 1.5. Directly after the campaign in 1989 a temporary increase occurred in the total number of melanomas diagnosed, largely due to more thin melanomas (

Site, histological type, and thickness of primary cutaneous malignant melanoma in western Netherlands since 1980.

An increasing incidence of cutaneous malignant melanoma had been observed in the Netherlands. Therefore, between 1989 and 1992 a preventive skin cancer campaign was organized in part of western Netherlands. The effect of this screening campaign has yet to be evaluated by investigating the distribution of all in situ and invasive primary cutaneous melanoma according to anatomical subsite, tumour thickness, and histological type in a population-based study during 1980-92. A total number of 2236 (1361 female; 875 male) invasive and 580 (395 female; 185 male) in situ melanomas were diagnosed. The median age of patients with thin lesions was 46 years, intermediate lesions 54 years, and thick lesions 65 years, which may be indicative of slow tumour progression. The median thickness of the invasive lesions was 0.9 mm for women and 1.1 mm for men and the invasive to in situ ratio was 3.4 for female and 4.7 for male subjects, suggesting a reasonable awareness of melanoma in this population. The relative tumour density (RTD) was remarkably high for melanomas in the head/neck area for both sexes and invasive melanoma on the male trunk and the lower legs of females. The low RTD of invasive melanomas on the lower limbs of men and the high density in the head/neck area for both sexes are remarkable and support the aetiological role of ultraviolet exposure. It is concluded that our findings are in many ways similar to those of other descriptive studies.