Cutaneous melanoma in children and adolescents and aspects of naevus phenotype in melanoma risk assessment

3 To Jan, Linus and Simon with love 4 5 " The important thing is not to stop questioning. Curiosity has its own reason for existing " A. Einstein 6 7 ABSTRACT Cutaneous malignant melanoma (CMM) is one of the most rapidly increasing cancers in the Swedish population. The aetiology of melanoma is a complex interplay between genetics, host characteristics and environmental factors. The host characteristic with the strongest association with CMM is a phenotype with high numbers of common naevi and with dysplastic naevi. The principal environmental factor is sun exposure. Melanoma risk assessment (paper I) In a multinational study including 986 subjects from Sweden, Denmark, the UK, Germany and the Netherlands, the ability of primary care physicians and nurses to identify individuals at increased melanoma risk was assessed. The atypical mole syndrome (AMS) scoring system for melanoma risk was used. The AMS scoring system consists of a five point check list incorporating total body naevus counts, clinically dysplastic naevi and body distribution of naevi. After brief training, the overall agreement in diagnosis between the trained personnel and experienced dermatologists was 94.5% (kappa value 0.70, p<0.05). The study showed that the scoring system successfully can be taught to personnel in primary care. The naevus phenotype in a population in northern Sweden (paper II) The naevus phenotype was investigated in a population living in the inland of northern Sweden with a low melanoma incidence. Two hundred and one participants from the community of Storuman were included. The median naevus count was15 common naevi/in-dividual, and the prevalence of dysplastic naevi was 11%. The median naevus count and prevalence of dysplastic naevi were significantly lower than previously described in populations with higher melanoma incidence and higher ambient ultraviolet exposure in southern Sweden. This geographical variation in naevus phenotype might be explained by differences in levels of sun exposure and in genotype. Cutaneous malignant melanoma in children and adolescents (papers III–V) During the years 1973 to 2002, 250 cases of primary CMM in individuals aged 0–19 years were reported to the Swedish Cancer Registry. Histological material was available for review in 87% of the cases registered during the two first decades (1973–1992). The diagnostic accuracy in the reviewed material was 88%. younger children the incidence remained extremely low, only 4 cases in children aged 0–9 years were reported during the studied 30-year period. The trunk was the most common melanoma site in boys, …