Board Review: Melanoma Risk Factors and Screening

Overview / Definition Melanoma is a type of skin cancer that arises from melanocytes, the pigment-producing cells in the skin. It is known for its potential to metastasize, making early detection vital for effective management. Melanoma can occur in various forms, with cutaneous melanoma being the most common, but it can also arise in mucosal sites and other non-cutaneous locations. Epidemiology Melanoma is one of the fastest-growing cancers worldwide, particularly in fair-skinned populations. The following statistics highlight its significance: Incidence rates have been rising, with an estimated 99,780 new cases expected in the U.S. in 2022. It accounts for 1% of all skin cancers but is responsible for the majority of skin cancer deaths. The lifetime risk of developing melanoma is approximately 1 in 38 for whites, 1 in 1,000 for blacks, and 1 in 167 for Hispanics. Pathophysiology / Mechanism The development of melanoma is influenced by a combination of genetic and environmental factors: **UV Radiation**: Exposure to ultraviolet (UV) light, especially intermittent intense exposure, is a major risk factor. **Genetic Mutations**: Common mutations include BRAF, NRAS, and TP53 mutations that lead to uncontrolled cell proliferation. **Familial Syndromes**: Conditions like Familial Atypical Multiple Mole Melanoma (FAMMM) syndrome significantly increase risk. Clinical Presentation Melanoma can present in various ways, often characterized by the ABCDE criteria: Asymmetry: One half of the mole doesn't match the other. Border irregularity: Edges are ragged, notched, or blurred. Color: The color is not uniform, with shades of brown, black, or tan, and sometimes red, white, or blue. Diameter: Melanomas are usually larger than 6mm (about the size of a pencil eraser). Evolution: The mole changes in size, shape, or color over time. Diagnosis / Workup Diagnosis of melanoma involves a thorough clinical assessment and, if indicated, histopathological confirmation: Clinical Examinatio