Histopathologic Distinguishing Features Between Lupus and Lichenoid Keratosis on the Face

BACKGROUND: The occurrence of lichenoid keratosis (LK) on the face is not well characterized, and the histopathologic distinction between LK and lupus erythematosus (LE) occurring on the face is often indeterminate. The authors aimed to describe differences between LE and LK occurring on the face by hematoxylin and eosin alone. METHODS: Cases of LK and LE were obtained using computer-driven queries. Clinical correlation was obtained for each lupus case. Other diagnoses were excluded for the LK cases. Hematoxylin and eosin–stained sections were reviewed. RESULTS: Forty-five cases of LK and 30 cases of LE occurring on the face were identified. Shared features included follicular involvement, epidermal atrophy, pigment incontinence, paucity of eosinophils, and basket-weave orthokeratosis. Major differences between LK and LE, respectively, included perivascular inflammation (11%, 90%), high Civatte bodies (44%, 7%), solar elastosis (84%, 33%), a predominate pattern of cell-poor vacuolar interface dermatitis (7%, 73%), compact follicular plugging (11%, 50%), hemorrhage (22%, 70%), mucin (0%, 77%), hypergranulosis (44%, 17%), and edema (7%, 60%). A predominate pattern of band-like lichenoid interface was seen more commonly in LK as compared with LE (93% vs. 27%). CONCLUSIONS: The authors established the occurrence of LK on the face and identified features to help distinguish LK from LE. Follicular involvement, basket-weave orthokeratosis, pigment incontinence, paucity of eosinophils, and epidermal atrophy were not reliable distinguishing features. Perivascular inflammation, cell-poor vacuolar interface, compact follicular plugging, mucin, hemorrhage, and edema favored LE. High Civatte bodies, band-like lichenoid interface, and solar elastosis favored LK.