Palmar and plantar lichen planus: a case report and review of the literature.

Palmoplantar lichen planus is an uncommon dermatosis. We present a case of 38-year-old Caucasian male with a history of pruritic, scaly lesions on the right plantar foot. Physical examination revealed whitish plaques and numerous spiny hyperkeratotic papules and focal scaling. A biopsy demonstrated orthohyperkeratosis and acanthosis of the epidermis. Immunohistochemical staining revealed positivity within the epidermis and/or lichenoid infiltrate with CD3, CD8, CD45, CD68, myeloid histiod antigen, BCL2, p27, p53, HLA-DPDQDR, metallothionein and tissue inhibitor of metalloproteinases 1. The diagnosis of PPLP was thus confirmed; this case illustrates that PPLP should be considered in the differential diagnosis of uncommon foot dermatoses with a significant junctional inflammatory component.