Clinical Description And Prevalence

The incidence of melanoma is rising faster than all other cancers except lung cancer in women, currently varying between 5 (Western Europe) and 20 (Northern Europe) to over 50 (Queensland, Australia) cases per 100,000 per annum.[1,2] Familial clustering of melanoma was first described by Norris in 1820,[3] but it was not until the second half of the 20th century before others documented the familial occurrence of melanoma. Across several population-based studies, 1-13% of melanoma cases reported the occurrence of melanoma in at least one first-degree relative.[4] Hence, it is commonly accepted that melanoma predisposition is hereditary in ~ 10% of all cases. But even in high-sun-exposure areas such as Queensland, Australia, less than 5% of melanoma probands report two or more first- or second-degree relatives affected with melanoma.[5]

Whereas susceptibility in small numbers of highly selected multiple-case melanoma families is consistent with autosomal dominant inheritance of a single major gene, segregation analysis in a large population-based sample of families failed to show a single major gene being responsible for melanoma transmission, possibly because of relatives' risk factors not being included in this analysis.[6] Thus, the bulk of familial clustering of melanoma may be better ascribed either to a codominant, a polygenic, or a recessive mode of inheritance.

In the absence of a characterized mutation there are no clear-cut criteria for ''familial melanoma,'' but as a working definition clinicians and researchers generally use this term to describe families in which there are at least three cases of melanoma. However, in low-sunlight areas such as northern Europe, familial melanoma is often defined when melanoma occurs in as few as two first-degree relatives. Additionally, individuals in whom multiple melanomas occur in the absence of a family history of the disease are of concern, because many of these cases have been found to harbor mutations in CDKN2A.[7] As will be illustrated below, clinical suspicion of a hereditary component should also arise when pancreatic cancer, uveal melanoma, or nervous system tumors occur in conjunction with melanoma in the same family.

How To Prevent Skin Cancer

How To Prevent Skin Cancer

Complete Guide to Preventing Skin Cancer. We all know enough to fear the name, just as we do the words tumor and malignant. But apart from that, most of us know very little at all about cancer, especially skin cancer in itself. If I were to ask you to tell me about skin cancer right now, what would you say? Apart from the fact that its a cancer on the skin, that is.

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