Lichen Simplex Chronicus (Squamous Hyperplasia)

Epidemiology:

• 2/3 are premenopausal

Common sites:

Gross features:

Histologic features:

• hyperkeratosis
• sometimes parakeratosis and hypergranulosis
• acanthosis
• mitotic activity may be present at basal and prickle cell layers
• no atypia
• superficial dermal inflammation

Immunophenotype:

Marker:

Sensitivity:

Specificity:

Molecular features:

Other features:

• secondary to scratching
• differential diagnosis:
• infections (tinea, candida, others)
• chemical exposures
• others
• not considered a premalignant lesion
• precursor to differentiated VIN (simplex)
• a less specific term is squamous hyperplasia