Melanoma of the Palms, Soles and Nail Bed: Acral Lentiginous Melanoma

Acral Lentiginous Melanoma is cutaneous malignant tumour which may arise on the foot. An irregular, enlarging black macule with a prolonged noninvasive stage. ALM found on the palms, soles and under the nails and occurs on non hair-bearing surfaces of the body which may or may not be exposed to sunlight. Unlike other forms of melanoma, acral lentiginous melanoma does not appear to be linked to sun exposure. ALM also known as subungual melanoma (source:wikipedia.org).

In 1969, reseachers histologically identified three sub-types – superficial spreading melanoma (SSM), nodular melanoma (NM) and lentigo maligna melanoma (LMM). In 1976, a fourth type, ALM was added. ALM represents the rarest of the four sub-types of cutaneous melanoma yet is the most common variety diagnosed on the foot, according to the one of Journal of Foot and Ankle medio September 2008. It was said in the article, its relative rarity, atypical appearance and late presentation frequently serve as poor prognostic indicators.

This sub-type of melanoma often occured on an area that seldom receives much sun exposure as this condition suggested that the aetiology is different from other sub-types of melanoma or that sun exposure is a lesser risk factor than another melanoma. It also has been suggested that Acral Lentiginous Melanoma itself carries a worse prognosis than other melanoma – often as lesions are recognised later than melanoma on other body sites.

Ivan R Bristow and Katharine Acland from School of Health Sciences, University of Southampton, and St Johns Institute of Dermatology, St Thomas Hospital, London, UK performed trial to identify all cases of ALM treated at the tertiary care melanoma centre located in a central London district. At a tertiary skin tumour centre, a retrospective review was undertaken of all patients diagnosed with the tumour at the level of ankle or below. And their results was:

This set of patients represents a small cohort (n = 27) of a population from an urban area with a high ethnic mix. Interestingly, despite the wide ethnic diversity of the local area, a high proportion of this cohort were white (69%). Despite the wide spread of ages (35 – 96), the average age of the patient in this study was 62.6 years which concurs with similar studies that ALM is most frequent in the 60–70 age group. ALM appears to occur in an older age group, other types of melanoma having a peak incidence around 50 years of age, albeit with a wider age spread.

See complete article about Melanoma of the Palms, Soles and Nail Bed: Acral Lentiginous Melanoma in 5 pages-337Kb of PDF download available (source: jfootankleres.com).