Mechanical Stress May Play a Role in Plantar Melanoma

Source: Dermatology Advisor, December 2019

Mechanical stress on the plantar surface of the foot, which is typical of normal weightbearing on the foot, is associated with a higher formation of plantar melanoma compared with other non-weightbearing areas of the body. This is according to study data in the Journal of European Academy of Dermatology and Venereology.

The study investigators retrospectively examined data from a melanoma database at the Peking Union Medical College Hospital. In their review, researchers identified 107 cases of acral melanoma diagnosed between August 1991 and June 2017. Cases included melanomas diagnosed on the sole (n=64), toes (n=10), fingers (n=5), and subungual location (n=28). A total of 72 cases were considered plantar melanoma and were included in the final analysis. A meta-analysis that examined studies with data on pathologic parameters of plantar melanoma based on varying mechanical stress exposures was also performed.

The heel was the most common region with plantar melanoma, followed by the forefoot, plantar aspect of the toes, lateral midfoot, and arch. A higher proportion of manual laborers had plantar melanoma on weightbearing areas vs non-manual laborers (90.9% vs 78.6%, respectively). There was a higher observed density of lesions in the posterior region of the feet as well as in the lateral forefoot.