Lichenoid interface dermatitis resembling that of idiopathic lichen planus. (A) Compact hyperorthokeratosis, thickened stratum granulosum and irregular acanthosis of the epidermis together with a superficial lichenoid lymphocytic infiltrate (hematoxylin-eosin, x100). (B and C) Higher magnification with necrotic keratinocytes up to the mid-epidermal layers (hematoxylin-eosin, x200).
