Cutaneous T-cell lymphoma (parapsoriasis en plaque). An association with pityriasis lichenoides et varioliformis acuta in young children.

Pityriasis lichenoides et varioliformis acuta (PLEVA) and pityriasis lichenoides chronica (PLC) are related benign disorders without recognized association with cutaneous T-cell lymphoma (CTCL). We report the cases of two children with documented PLEVA evolving into CTCL over several years. One child had the clinical lesions of PLC but the dermatopathologic findings of PLEVA at age 2 years. At age 12 years, he had skin changes of poikiloderma atrophicans vasculare and dermatopathologic findings consistent with parapsoriasis en plaque. The second child presented at age 7 years with scaling dermatitis and dermatopathologic findings of PLEVA. At age 12 years, the histologic diagnosis was parapsoriasis. Monoclonal antibody studies performed on biopsy specimens from both patients revealed 70% to 100% cells staining with CD5, 80% to 90% staining with CD4, 30% to 50% staining with CD8, and an increase in CD1-staining cells in the papillary dermis, indicating a predominantly helper T-cell infiltrate. We believe that PLC and PLEVA may be part of the spectrum of CTCL. Furthermore, CTCL may be more common in young children than once thought.