A Histopathologic and Immunogenetic Analysis of Primary Cutaneous B-cell Lymphomas in Korea

Kim, Jae Wang; Lee, Chong Ju

Abstract

BACKGROUND
Despite the advent of molecular biology and immunogenetics, the biologic behaviors and disease entities of primary cutaneous B-cell lymphomas(pCBCL) have been undetermined. Moreover, rarity of pCBCL cases and the conflicting datas of current issues have contributed to the dilemmas in understanding of the biology of pCBCL. Until now, a study of the overall features of pCBCL in Korea has been rarely presented. OBJECTIVE: We performed this study in order to identify the histopathologic and immunogenetic characteristics of pCBCL in Korea. METHODS: The histopathologic, immunophenotypic and molecular analysis of preserved specimens of 15 cases with pCBCL were conducted. RESULTS: 1. Of the 15 patients with pCBCL, most common types are follicle center cell lymphomas(73.3%). In REAL classification, diffuse large B-cell lymphoma is most common(66.6%). 2. In bcl-2 immunohistochemical staining, 3 cases(20%) were positive. 3. Only one of 15 cases of pCBCL denoted bcl-2 gene rearrangement by t(14;18) in minor cluster region. 4. Immunohistochemical staining demonstrated overexpression of p53 protein in 3(20%) of 15 cases. 5. 2 cases(13.3%) with point mutations(one for exon 5; the other for exon 8) in p53 DNA sequencing analysis. CONCLUSION: t(14;18) translocation may be rare in pCBCL in Korea. This finding indicates that bcl-2 expression by tumor cells in pCBCL without t(14;18) may occur by different genetic dysregulation. It seems to be that overexpression of p53 protein might not correspond with p53 mutations in pCBCL.