Phenotipic characterization of Brazilian families with the familial melanoma syndrome

• Grant number: 10/11251-6
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2010
• End date: October 31, 2012
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: João Pedreira Duprat Neto
• Grantee: João Pedreira Duprat Neto
• Host Institution: Hospital A C Camargo. Fundação Antonio Prudente (FAP). São Paulo , SP, Brazil
• Associated researchers: Bianca Costa Soares de Sá ; Gilles Landman

Abstract

Cutaneous malignant melanoma (CMM) includes 2 clinical extremes. At one end, thin primary CMM with high cure rate. At the opposite end, metastatic melanoma, characterized by low cure rate and poor outcomes. Prevention is essential to decrease the risk of CMM (MARKOVIC et al. 2007). Some phenotypic characteristics are related with a higher risk for the development of this disease, such as: skin type (sensitivity to the sunlight), freckling, eye and hair color and dysplastic nevi (GANDINI et al. 2005). The familial melanoma syndrome (FMS) may be characterized by some factors: multiple members affected (at the same branch), multiple primary melanoma (MPM) (2 or more) at the same individual or CMM at a young age by the time of diagnostic. The family may also present cases of pancreatic cancer, Central Nervous Systems cancer or ocular melanoma in first or second grade relatives (VASEN et al. 2000; KANNENGIESSER et al. 2003). Progress on genetics regarding CMM lead to the identification of three high penetrance genes: CDKN2A (cyclin-dependent kinase inhibitor 2 A), ARF and CDK4 (cyclin-dependent kinase 4) (PHO et al. 2006). And one of low penetrance: MC1R (melanocortin receptor gene) (PALMER et al. 2000). CMM is the interaction of genetic, environmental and constitutional factors and it is rapidly increasing in white-skinned population, thus improved preventive strategies are needed. Our goal is to identify the phenotypic characteristics (PC) of this population (FMS) and to compare it regarding those who have the mutation on CDKN2A with those who do not have it.The PCs evaluated are: eye color and pigmented lesions on the iris, hair color, skin type (Fitzpatrick), freckles and mole count. This study will include 60 patients with MPM or families with the FMS. The cases of melanoma, pancreatic cancer and central nervous system tumor must have histopathology reports. The participants will be characterized by clinical data in order to evaluate the phenotypic prevalence. The PC will be evaluated through descriptive statistic (mean, standard deviation, median, percentage). We will use chi-square test or Fisher's exact test to compare the PC regarding the mutation on CDKN2A gene. (AU)