Risk factors in a cohort of patients with multiple primary melanoma.

BACKGROUND: There are various known familial and environmental risk factors that influence the risk for melanoma. This study sought to define the risk factors for multiple primary melanoma.

METHODS: A telephone survey of patients with multiple primary melanomas was conducted from a private practice in south-east Queensland, in order to examine various risk factors in this cohort.

RESULTS: Our findings of high rates of family history of melanoma (37%), and of dysplastic naevi (42%) support the influence of genotype in this high-risk group. A family history of multiple primary melanomas, seen in 17% of our patients, is a risk factor not previously reported in similar cohort studies. Sixty-eight per cent of patients had an equal or lesser degree of invasive malignancy in subsequent melanomas. Most multiple primary melanoma patients in this group (86.6%) were conducting self skin examination at least once per month. With regards to sun-protective behaviour, 85% reported regular sunscreen use and 92% reported regular use of sun-protective clothing; however, fewer had done this in childhood.

CONCLUSIONS: Enhanced knowledge of the genetic and environmental risk factors for multiple primary melanomas can assist clinicians in assessing risk and planning surveillance of patients.