Lichenoid keratosis

Lichenoid keratosis is a benign skin condition.

It is also known as lichen planus-like keratosis.

General

• Caucasians - middle age or older.
• May be a variant of seborrheic keratosis (with marked inflammation).

Clinical DDx:

• Basal cell carcinoma, squamous cell carcinoma of the skin, melanocytic neoplasm.

Gross

• Red raised scaly-appearing lesion.

Microscopic

Features:

• Hyperkeratosis.
• Parakeratosis.
• Band of inflammatory cells at DE junction (lichenoid inflammation).
• Dead keratinocytes (Civatte bodies).
• Dermal melanophages.

DDx:

• Lichen planus - need clinical correlation (mucosal lesions).
• Drug reaction.
• Cutaneous T-cell lymphoma.
• Regressed melanocytic lesion, esp. malignant melanoma.
• Lichenoid actinic keratosis - has atypical hyperchromatic basal cells - esp. at edge of lesion, usu. in the context of solar elastosis.

Images

• Lichenoid keratosis (dermpedia.org).

Sign out

SKIN LESION, MID-MIDDLE BACK, PUNCH BIOPSY:
- LICHENOID KERATOSIS.

Incompletely excised

SKIN LESION, LEFT CHEST, PUNCH BIOPSY:
- LICHENOID KERATOSIS VERSUS ACTINIC KERATOSIS.
- NEGATIVE FOR BASAL CELL CARCINOMA.
- SEE COMMENT.

COMMENT:
No eosinophils are apparent. No melanocytic lesion is identified; however, excision of the
whole lesion to exclude a partially regressed melanocytic lesion is suggested.

Micro

The sections show skin with lichenoid inflammation and mild overlying hyperkeratosis with very rare parakeratosis. There is no significant basal atypia. Rare eosinophils are seen. The lymphocytes do not show apparent atypia. Mild reactive spongiosis is seen.

See also

• Non-malignant skin disease.