Table 1: ABCDEF rule for melanoma of the nail apparatus [12].

A  (age) - peak incidence between the fifth and seventh decades of life;

B (nail band) - Change of colors - from brown to black or thickness greater than 3 mm  or irregular edges;

C (change) - Quick and recent increase in the size of the band or change in morphology of the nail;

D (digit involved) - a pigmented band in a single digit;

E (extension) - Extension of pigment in the proximal or lateral periungual - sign Hutchinson;

F (family) - Personal or familial history of nevus syndrome or melanoma displástico.