A 65-year-old man consulted for a non healing ulceration on his right heel.
This ulceration had been occuring on a pigmented lesion present for 5 years. The clinical diagnosis of acral lentiginous melanoma was quite evident on examination.
Melanoma on the palms and soles have a distinct pigment network called parallel ridge pattern. The ridges are centered by white dots which are the openings of eccrine sweat ducts.
In our case, in certain areas parallel ridge pattern had disappeared and was replaced by uniform diffuse brown pigmentation (in which white dots are visible).
An acral lentiginous melanoma has to be differentiated from black heel (or subcorneal hemorrhage) which displays a parallel pattern.