Acral Lentiginous Melanoma

Acral lentiginous melanoma (ALM), also sometimes referred to as, simply, acral melanoma, is melanoma occurring on the hands and feet (palms, soles, fingers, toes, and nail units). The word acral derives from the Greek word referring to the highest or topmost portion of the limbs (extremities). The same stem word is used for the city of Akron (in Summit County, Ohio, the highest elevation on the Ohio and Erie Canal), and the acropolis (the rocky outcrop in Greece on which the Parthenon sits). Lentiginous refers to the initial origin of these tumors as a macular (flat) brown spot, resembling a benign lentigo.

The term melanoma refers to a malignancy of melanocytes, the pigment-producing cells in the epidermis. Acral melanoma was first separated as a distinct subtype of cutaneous malignant melanoma (CMM) by Arrington et al. in 1977. It is the least common subtype of melanoma, comprising only 2 to 3% of total melanoma diagnoses. Unlike other CMM, UV-radiation is not thought to play a significant part in the development of ALM. It is most commonly on the lower extremities and is often advanced at the time of presentation leading to a high level of morbidity and mortality. It has a higher proportional incidence in non-white populations compared to other subtypes of melanoma. In this article, we will discuss the unique aspects of this disease.