ORIGINAL ARTICLES: EpidemiologyCharacterization of nonacral melanoma patients without typical risk factorsCanelas, Maria M.a; Bermejo, Justo Lorenzoc,d; Landi, Maria Teresae; Requena, Celiaa; Guillen, Carlosa; Kumar, Rajivd; Nagore, Eduardoa,bAuthor Information aDepartment of Dermatology, Instituto Valenciano de Oncologia bDepartment of Dermatology, Universidad Católica de Valencia, Valencia, Spain cInstitute of Medical Biometry and Informatics, University Hospital Heidelberg dDivision of Molecular Genetic Epidemiology, German Cancer Research Center, Heidelberg, Germany eGenetic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland, USA Correspondence to Eduardo Nagore, MD, PhD, Department of Dermatology, Instituto Valenciano de Oncología, C/Profesor Beltrán Báguena 8, E-46009 Valencia, Spain Tel: +34 961 114 016; fax: +34 961 114 346; e-mail: [email protected] Received October 5, 2011 Accepted March 26, 2012 Melanoma Research: August 2012 - Volume 22 - Issue 4 - p 316-319 doi: 10.1097/CMR.0b013e3283541460 Buy Metrics Abstract A divergent pathway model to cutaneous melanoma is commonly accepted: sun sensitivity/chronic sun exposure and melanocytic instability. Although this dual model explains the development of most melanomas, clinical experience suggests other possible routes. The aim of this study was to explore the characteristics of patients who do not fit with these two pathways. We selected 818 patients with nonacral cutaneous melanoma and defined three groups: nevus-prone individuals, sun-sensitive individuals, and non-nevus-prone and non-sun-sensitive individuals. This group included patients without identifiable melanoma risk factors and comprised 52 patients (5.5% of the overall nonacral melanoma population). These patients were more frequently women, were more likely to present melanoma at a very young age (13.5% before 25 years), to have less frequent personal history of melanoma and remnants of pre-existing nevi, and to present tumors on the trunk and legs. We have identified a group of patients with fewer risk factors for melanoma that needs further studies to increase our understanding of melanoma development. © 2012 Lippincott Williams & Wilkins, Inc.