Nam-Cha S H, San-Millán B, Mollejo M, García-Cosio M, Garijo G, Gomez M, Warnke R A, Jaffe E S, Piris M A
Lymphoma Group, Molecular Pathology Programme, Spanish National Cancer Centre (CNIO), Madrid, Spain.
Histopathology. 2008 Mar;52(4):436-44. doi: 10.1111/j.1365-2559.2008.02965.x.
Light-chain-restricted germinal centres are generally associated with the existence of a neoplastic lymphoproliferative disorder. The aim was to present a series of cases with persistent lymph node enlargement that featured some germinal centres showing light chain immunoglobulin restriction.
A series of six reactive lymphadenitis and two Castleman's disease cases was analysed by immunohistochemistry, IgH-polymerase chain reaction (PCR) and microdissected PCR. In all cases some germinal centres contained a population of plasma cells and plasmacytoid germinal centre cells showing light chain immunoglobulin restriction. In three cases the monotypic cells also showed distinct Bcl-2 expression. Two of the cases showed a predominant IgH rearrangement on a florid polyclonal background and one had an IgH monoclonal rearrangement, as revealed by PCR. Microdissected germinal centre PCR revealed a dominant repeated band in one of three cases and in another case a non-repeated clonal peak was observed. One of the patients developed a follicular lymphoma, which became evident from a subsequent biopsy.
These findings may be a manifestation of an underlying disorder in the regulation of the immune response, or an exaggeration of the germinal centre oligoclonal nature. This should be taken into account in the differential diagnosis of follicular hyperplasia.
轻链受限的生发中心通常与肿瘤性淋巴细胞增殖性疾病的存在相关。目的是呈现一系列持续性淋巴结肿大病例，其特征为一些生发中心显示轻链免疫球蛋白受限。
通过免疫组织化学、免疫球蛋白重链（IgH）聚合酶链反应（PCR）和显微切割PCR分析了一系列6例反应性淋巴结炎和2例Castleman病病例。在所有病例中，一些生发中心含有一群显示轻链免疫球蛋白受限的浆细胞和浆细胞样生发中心细胞。在3例病例中，单型细胞也显示出明显的Bcl-2表达。PCR结果显示，2例病例在活跃的多克隆背景上显示出主要的IgH重排，1例有IgH单克隆重排。显微切割生发中心PCR在3例中的1例中显示出一个占主导地位的重复条带，在另一例中观察到一个非重复的克隆峰。其中1例患者发展为滤泡性淋巴瘤，随后的活检证实了这一点。
这些发现可能是免疫反应调节潜在紊乱的表现，或者是生发中心寡克隆性质的夸大。在滤泡性增生的鉴别诊断中应考虑到这一点。
