The Presence of Mast Cells in Lichen Planopilaris and Discoid Lupus Erythematosus of the Scalp: A Quantitative Study Publisher Pubmed



Shahididadras M¹ ; Asadi Kani Z¹ ; Dadkhahfar S¹ ; Zartab H^{2, 3} ; Rakhshan A^{1, 4} Show Affiliations
Source: Journal of Cutaneous Pathology Published:2022

Abstract

Background: Histopathologic differentiation of lichen planopilaris (LPP) and discoid lupus erythematosus (DLE) as two common causes of primary cicatricial alopecias remains challenging. Method: We performed a histopathologic study on a case series of LPP and DLE specimens to investigate the number, distribution, and morphology of mast cells as indices for differentiation of these two entities. H&E investigation and Giemsa staining for the detection of mast cells was performed. Result: A total of 74 cases comprising 50 cases of LPP and 24 cases of DLE were assessed. The mean mast cell count and percentage were significantly higher in LPP group (p < 0.001). Mean degranulated mast cell count and the mean intact mast cell count were also significantly higher in LPP patients (p < 0.001). Most of the specimens, 58 (78.4%), showed both perifollicular and perivascular distribution of mast cells without significant difference between two groups. The morphology of mast cells was predominantly round-oval in 85.5%, predominantly fusiform in 13.5% with more frequent fusiform morphology in DLE group. Conclusion: The mast cell count detected by Giemsa staining could assist pathologists in distinguishing between LPP and DLE. © 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.