Melanoma – Lentigo Maligna

October 9th, 2011

Lentigo Maligna is a subtype of Melanoma that I commonly encounter in both my The Woodlands dermatology and Conroe dermatology offices.  Lentigo Maligna typically occurs on sun-exposed areas such as the face.  Clinically, a Lentigo Maligna appears as a brown/black enlarging flat patch with multiple colors and irregular edges.  Fortunately, Lentigo Maligna has a prolonged radial phase in which it grows horizontally in the epidermis for 5-20 years as an in situ melanoma before it penetrates the dermis and has the ability to metastasize.  Thus, early detection of a Lentigo Maligna has a very high 5 year survival rate.  Treatment of a Lentigo Maligna is wide excision although Mohs surgery has been utilized for some cases.  At least a 5mm margin is utilized with the wide excision but some dermatologists prefer a 1cm margin as Lentigo Malignas are notorious for subclinical extension beyond 5mm of clinically normal appearing skin.