Lentigo maligna part I: Epidemiology, risk factors, and diagnosis.

Lentigo maligna (LM) is an increasingly common subtype of melanoma, presenting as a slow-growing tan-brown macule or patch with irregular borders arising on chronically solar-damaged skin. This 2-part continuing medical education series provides an overview of LM. Part I reviews LM's epidemiology, risk factors, and clinical presentation. Clinical tools to aid in diagnosis - such as dermoscopy and reflectance confocal microscopy - are discussed, as well as optimal biopsy strategies. Histopathology and current understanding of molecular underpinnings are also reviewed. Management of LM presents unique challenges, given a predilection for subclinical spread on functionally and cosmetically sensitive areas such as the face. Part II reviews the 2 pillars of management including both surgical and nonsurgical treatment options and surveillance.