Quiz: Acral lentiginous melanoma

August 29, 2017

In this installment of our melanoma case studies series, we focus on factors associated with acral lentiginous melanoma.

 

ANSWER

3. Acral lentiginous melanoma

 

ANSWER

3. Acral lentiginous melanoma

Acral lentiginous melanoma is most commonly found on the palms, soles and nail beds (1). In a previous study that evaluated melanomas located on the hands and feet, approximately half were found to be of the acral lentiginous subtype (2).  Prior trauma and nevi on the soles and toes were determined to be risk factors for this melanoma subtype (2).

 

ANSWER

3. Acral lentiginous melanoma

Acral lentiginous melanoma is the most common subtype of melanoma arising in patients of Asian or African origin (1). In a recent study conducted in Mexico, acral lentiginous melanoma was found in 44.1% of the Mexican and Latin American people (3). In people of color, acral lentiginous melanoma accounts for the highest proportion of all subtypes of melanoma (4). The melanoma cancer rate among Caucasians in Australia is one of the highest worldwide, but that does not include the acral lentiginous variant, which is not photo-induced.

 

ANSWER

1. Yes

Mechanical stress, including plantar pressure and shear stress, on the plantar surface of the foot, especially the rear foot and front of the foot, is associated with ulcer formation in diabetes patients as well as calluses. As a result, mechanical stress on the plantar foot increases risk of melanoma development in these patients (5).

 

ANSWER

2. No

Acral lentinginous melanoma is not associated with sun exposure, and therefore, cannot prevented in this manner (3).

 

ANSWER

False

The prognosis of acral lentiginous melanoma, like all melanoma subtypes, is dependent on its Breslow depth or stage.  Since this is the most frequently delayed melanoma subtype to be diagnosed, this subtype of melanoma tends to be more advanced when found and its prognosis is often worse than that of other subtypes of melanoma (1). The acral lentiginous subtype is an independent risk factor for melanoma and overall bodes for worse survival (3).

 

ANSWER

Yes

Melanoma subtype does not dictate surgical margin. Breslow depth or stage do. When diagnosed at an early stage, acral lentiginous melanoma can be excised with margins described previously, and sentinel node biopsy considered if appropriate as described previously (3).

REFERENCES

Goydos JS, Shoen SL. Acral Lentiginous Melanoma. Cancer Treat Res. 2016;167:321-9.

Durbec F, Martin L, Derancourt C, et al. Melanoma of the hand and foot: epidemiological, prognostic and genetic features. A systematic review. Br J Dermatol. 2012 Apr;166(4):727-39.

Lino-Silva LS, Domínguez-Rodríguez JA, Aguilar-Romero JM, et al. Melanoma in Mexico: Clinicopathologic Features in a Population with Predominance of Acral Lentiginous Subtype. Ann Surg Oncol. 2016 Dec;23(13):4189-4194.

Bradford PT, Goldstein AM, McMaster ML, et al. Acral lentiginous melanoma: incidence and survival patterns in the United States, 1986-2005. Arch Dermatol. 2009 Apr;145(4):427-34.

Minagawa A, Omodaka T, Okuyama R. Melanomas and Mechanical Stress Points on the Plantar Surface of the Foot. N Engl J Med. 2016 Jun;374(24):2404-6.