A 35-year-old woman consulted for a pigmented lesion on the sole of her left foot.The dermoscopic feature was typical of a fibrillar pattern.
The fibrillar pattern was uniform and localized on the entire surface of the lesion. That was in favor of a benign acral melanocytic nevus.
The fibrillar pattern is a subtype of parallel furrow pattern observed on high-pressure areas and in hyperkeratotic areas.
Fibrillar pattern are quite never observed on palmar surface.
It has to be reminded that fibrillar pattern is in favor of a benign acral nevus only if it occupies the whole surface of the lesion. Melanomas can dysplay a fibrillar pattern in focal areas in a disorganized manner.
Reference:
Braun RP, Kopf AW, Marghoob AA. Comment on dermoscopy patterns of melanocytic nevi on the sole. J Am Acad Dermatol 2006; 55: 162-3
Other cases of fibrillar pattern: 1 2 3
