Parapsoriasis en plaques: Its potential for progression to malignant lymphoma

• Published in: Journal of the American Academy of Dermatology Vol. 29; no. 3; pp. 419 - 422
• Main Authors: Kikuchi, Arata, Naka, Wataru, Harada, Takashi, Sakuraoka, Koichi, Harada, Reiko, Nishikawa, Takeji
• Format: Journal Article
• Language: English
• Published: New York, NY Mosby, Inc 01.09.1993; Elsevier
• Subjects: Adult; Aged; Biological and medical sciences; Dermatology; Female; Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; Humans; Immunophenotyping; Lymphoma, T-Cell, Cutaneous - genetics; Lymphoma, T-Cell, Cutaneous - pathology; Male; Medical sciences; Middle Aged; Parapsoriasis - genetics; Parapsoriasis - pathology; Precancerous Conditions - genetics; Precancerous Conditions - pathology; Psoriasis. Parapsoriasis. Lichen; Human; Immunohistochemistry; Skin disease; Exploration; Malignant hemopathy; Non Hodgkin lymphoma; Differential diagnostic; Peripheral T cell lymphoma; Parapsoriasis en plaque; Pathology; Symptomatology; Association; Lymphoproliferative syndrome; Skin
• ISSN: 0190-9622; 1097-6787
• DOI: 10.1016/0190-9622(93)70204-7

Background: Parapsoriasis en plaques (large-plaque type) is a premalignant condition capable of developing into cutaneous T-cell lymphoma (CTCL). However, it is not known whether the early stage of CTCL can be distinguished from parapsoriasis en plaques. Objective: Our purpose was to determine whether parapsoriasis en plaques can develop into CTCL. Methods: The clinical appearance, histopathologic features, immunophenotype, DNA rearrangements, and clinical course were analyzed in 20 cases. Results: T-cell receptor β-chain gene rearrangement was detected in four of the 20 cases. No clinical, histopathologic, or immunohistochemical differences were found between patients with and without gene rearrangement. Conclusion: The early stage of CTCL cannot be differentiated from parapsoriasis en plaques by clinical features, histopathologic characteristics, or immunophenotype. Patients with parapsoriasis en plaques exhibit heterogeneous findings, which may include monoclonal proliferation. Patients with long-standing parapsoriasis-like lesions resistant to conventional treatment require careful monitoring for the possible development of cutaneous lymphoma.