Cutaneous T‐cell Lymphoma of 12 Years Duration Initially Presenting in a Two Year Old

A 67‐year‐old Chinese man presented with a longstanding history of asymptomatic, brown‐red macules that diffusely involved his trunk and the extremities and was associated with generalized lymphadenopathy. His serum protein electrophoresis revealed a polyclonal hypergammaglobulinemia. No monoclonal Bence Jones protein was detected in the urine. Flow cytometry of his peripheral blood revealed a normal polyclonal population of B and T cells. Histopathologic examination demonstrated a dense nodular infiltrate of lymphocytes and numerous mature plasma cells in the reticular dermis. Immunoperoxidase studies for kappa and lambda light chains failed to demonstrate clonality. In addition, immunoglobulin gene rearrangement studies failed to reveal a monoclonal band. A bone marrow biopsy showed no abnormality. Cutaneous and systemic plasmacytosis is a rare lymphoproliferative disorder that is an important consideration in the differential diagnosis of cutaneous infiltrates in which plasma cells predominate.