Kappa Chain Monoclonal Primary Cutaneous Plasmacytoma / 대한피부과학회지

ABSTRACT

Primary cutaneous plasmacytoma is a rare type of cutaneous B-cell lymphoma that arises primarily in the skin, and this is derived from clonally expanded plasma cells with various degrees of maturation and atypia. A 72-year-old man had an asymptomatic, solitary reddish to violaceous nodule on the back for about 4 months. The histologic finding of the skin biopsy specimen demonstrated an infiltration of variably matured plasma cells in the dermis, and these cells showed a monotypic expression of immunoglobulin kappa chains on immunohistochemical staining. Staging investigations excluded any extracutaneous manifestations of the disease. Only a few cases of primary cutaneous plasmacytoma have been published in the Korean dermatologic literature. Herein, we report on an interesting case of primary cutaneous plasmacytoma with monoclonality of kappa chains.