RESUMO
BACKGROUND: Lymphomatoid papulosis is a benign cutaneous eruption that in 10 to 20 percent of patients is associated with the development of lymphoma. The atypical cells of lymphomatoid papulosis histologically resemble the malignant cells of cutaneous T-cell lymphoma or the Reed-Sternberg cells of Hodgkin's disease. We studied a patient in whom lymphomatoid papulosis developed in 1971, Hodgkin's disease in 1975, and cutaneous T-cell lymphoma in 1985, to determine whether these diseases are clonally related. METHODS: The T-cell-receptor alpha-chain gene was cloned and sequenced from a cell line derived from the advanced-stage cutaneous T-cell lymphoma, and the polymerase chain reaction was used to search for this rearrangement of the alpha-chain gene in tissues obtained earlier that were affected by Hodgkin's disease or lymphomatoid papulosis. RESULTS: The tumor-specific rearrangement of the alpha-chain gene was detected in the patient's earlier tissues affected by lymphomatoid papulosis and Hodgkin's disease, but not in control tissue, including uninvolved tissues from the staging laparotomy for Hodgkin's disease. Cytogenetic studies revealed a translocation, t(8;9)(p22;p24), in cutaneous T-cell lymphoma lines and in a dermatopathic lymph node removed two years before the clinical onset of the cutaneous T-cell lymphoma. Immunohistochemical findings were consistent with an activated T-cell phenotype for the atypical cells of lymphomatoid papulosis, the Reed-Sternberg cells of Hodgkin's disease, and the malignant cells of the T-cell lymphoma. CONCLUSIONS: Lymphomatoid papulosis, Hodgkin's disease, and cutaneous T-cell lymphoma can be derived from a single T-cell clone. A t(8;9) genetic translocation may be involved in the pathogenesis of lymphomatoid papulosis or its progression to malignant disease.
