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The molecular biology of melanoma

Ryan J Sullivan, MD
David E Fisher, MD, PhD
Section Editor
Michael B Atkins, MD
Deputy Editor
Michael E Ross, MD


Melanoma is among the most common cancers in the United States, causing 87,000 cases and 9700 deaths annually, and its incidence has risen dramatically [1]. Worldwide, melanoma accounts for 352,000 cases and 60,000 deaths annually [2]. (See "Risk factors for the development of melanoma", section on 'Epidemiology'.)

Although patients with localized disease can be treated successfully with surgical resection in the majority of cases, some individuals present with or subsequently develop disseminated disease. The prognosis for patients with distant metastases from melanoma is poor, and the vast majority of those with stage IV melanoma will die from their disease.

An increasing understanding of melanocyte biology and melanoma pathogenesis is leading to the development of targeted therapies and the potential for major improvements in the care of patients with advanced melanoma. The most important breakthroughs have been the discovery that the mitogen-activated protein kinase (MAPK) pathway is the key signaling pathway and the elucidation of the critical role of microphthalmia-associated transcription factor (MITF).

This topic provides an overview of melanocyte biology and the important molecular alterations of genes and signaling pathways that are critical to the development and pathogenesis of melanoma. The clinical results with targeted agents that are being developed based upon this information are discussed separately. (See "Molecularly targeted therapy for metastatic melanoma".)


Melanocytes are the pigment-containing cells of the skin that produce melanin in response to stimuli such as ultraviolet (UV) radiation. Melanocytes also make the pigment that determines skin and hair color.

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Literature review current through: Nov 2017. | This topic last updated: Jan 10, 2017.
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