three times as many cases in the South (8). Americans have a one in 84 risk of developing melanoma (4). The risk has increased from one in 1,500 67 years ago, to one in 250 in 1980, and is predicted to be one in 75 by the year 2,000 (3). Other countries, including Australia, Austria, Canada, Germany, Italy, and Scotland have also reported such increases. The overall incidence rate for melanoma is increasing faster than the rate for any other cancer.
Diagnosis of melanoma is usually made initially by a history and physical examination (28). Two different checklists have been devised to help in diagnosis of melanoma. The first, the ABCD list, looks at asymmetry (A), border irregularity (B), color variegation (C), and diameter (D) when the diameter is greater than sic mm. The seven-point system includes three major criteria - change in size, shape, and color - and four minor criteria - inflammation, crusting or bleeding, sensory change, and a diameter greater than or equal to 7 mm.
Approximately 10 percent of cutaneous melanomas occur in families in which several members are affected, and the familial predisposition to this disease is often associated with dysplastic nevus syndrome (20). The chromosome region 9p21 and markers on chromosomes 1p and 6p have been linked to melanoma susceptibility (20). The tumor suppressor genes CDKN2A and CDKN2B have been mapped to the 9p21 region, and genetic analyses have revealed the presence of germline CDKN2A alterations in melanoma families, but the frequencies of such alterations vary among these families. CDKN2A germline gene mutations were observed in 7.8 percent of 64 Swedish melanoma kindreds in this study, and each family included at least two first-degree relatives with melanoma and dysplastic nevus syndrome. Fitzgerald et al (10) also found cyclin-dependent kinase (CDK) inhibitor p16 germline mutations present in a significant fraction of individuals who have melanoma and a p...