Lichen planus follicularis tumidus: Immunotyping of the inflammatory infiltrate with focus on plasmacytoid dendritic cells.

Abstract

Lichen planus follicularis tumidus (LPFT) is a rare clinicopathological variant of lichen planus (LP), clinically presenting with red-to-violaceous plaques studded with comedo-like lesions and keratin-filled milia-like cysts. Histopathologically, LPFT is characterized by cystically dilated follicular infundibula in the dermis, surrounded by a dense lichenoid lymphoid infiltrate with an associated interface reaction. We describe the clinicopathological features of an additional case of LPFT, focusing on the number and distribution of CD123(+) TCF4(+) plasmacytoid dendritic cells (pDCs). In our case, pDCs represented approximately 5% of the total inflammatory infiltrate, predominantly exhibiting a lichenoid distribution around the infundibula with no evidence of cluster formation, thus ruling out cutaneous lupus erythematosus. Our report is the first to describe the number and distribution of pDCs in LPFT. The results of our immunohistochemical analysis corroborate the notion that LPFT should be regarded as a rare variant of LP.

• Authors: Andrea Saggini, Werner Kempf, Heinz Kutzner
• Journal: Journal of cutaneous pathology (J Cutan Pathol) Vol. 47 Issue 10 Pg. 923-928 (Oct 2020) ISSN: 1600-0560 [Electronic] United States
• PMID: 32458476 (Publication Type: Case Reports)
• Copyright: © 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Chemical References

• Interleukin-3 Receptor alpha Subunit
• TCF4 protein, human
• Transcription Factor 4

Topics

• Biopsy (methods)
• Dendritic Cells (metabolism, pathology)
• Diagnosis, Differential
• Humans
• Immunohistochemistry (methods)
• Immunophenotyping (methods)
• Interleukin-3 Receptor alpha Subunit (metabolism)
• Lichen Planus (diagnosis, genetics, pathology)
• Lupus Erythematosus, Cutaneous (diagnosis)
• Male
• Middle Aged
• Skin Diseases, Papulosquamous (pathology)
• Transcription Factor 4 (metabolism)