Seborrheic keratosis
LEGEND
There are several histological subtypes, the most common being the acanthotic form, as shown in the image.
Other histological subtypes include:
- Hyperkeratotic
- Reticulated
- Inflamed or irritated
- Clonal
- Melanoacanthoma
Epidermal proliferation without atypia
Frequent presence of horn cysts.
Seborrheic keratosis
Proliferation may be endophytic, exophytic, or reticulated.
The basement membrane may be pigmented.
Seborrheic keratosis – reticulated and inflamed
LEGEND
Some atypia and mitoses may occur when the lesion is inflamed.
Reticulated epidermal proliferation with presence of horn cysts
Mixed lichenoid and superficial perivascular inflammatory infiltrate
