The color of the skin of the palms and soles as a possible clue to the pathogenesis of acral-lentiginous melanoma.

It is obvious clinically that skin of the palms and soles (volar skin) of blacks is lighter in color than black glabrous skin. The same difference obtains in whites, but is much less obvious. The distribution of melanosomes within keratinocytes of the palms and thighs of blacks and whites was compared. Keratinocytes in skin from the thighs of blacks contained only individually dispersed melanosomes, but keratinocytes in skin from the palms of blacks and from the palms and thighs of whites contained complexed melanosomes. Our observation may explain why the incidence of melanoma of volar skin in blacks and whites is similar, whereas melanoma on the glabrous skin of blacks is extremely rare.