A 90-year-old woman consulted for a pigmented lesion on her forehead.
Dermoscopy revealed a brown pigmentation with multiple blue-gray dots.
The lesion was excised and pathology revealed a seborrheic keratosis.
This lesion was probably regressing to a lichenoïd keratosis (or lichen planus-like keratosis).
See the literature:
Zaballos P. et al. Dermoscopic pattern of intermediate stage in seborrhoeic keratosis regressing to lichenoid keratosis: report of 24 cases. Br J Dermatol. 2007 Aug;157(2):266-72
