Department of Pathology, Queen Mary Hospital, Hong Kong, China.
Mod Pathol. 2010 Apr;23(4):493-501. doi: 10.1038/modpathol.2009.168. Epub 2010 Jan 8.
Diffuse large B-cell lymphoma that develops in the setting of long-standing chronic inflammation is typically associated with Epstein-Barr virus, and usually presents as tumor mass involving body cavities, as in pyothorax-associated lymphoma. It is listed as a distinct entity in the latest World Health Organization lymphoma classification. We report four cases that were incidentally discovered on histologic examination, one each in a splenic false cyst, a long-standing hydrocele, an atrial myxoma, and metallic-implant wear debris. Microscopic foci of atypical (neoplastic) large lymphoid cells were found within the contents of the cysts or curettage material, or within the stroma of the atrial myxoma. Despite the diverse clinical scenarios, all cases showed a homogeneous phenotype: positivity for B-lineage markers (CD20+, CD79a+, PAX5+), non-germinal center immunophenotype (CD10-, BCL6-/+, MUM-1+), and positivity for Epstein-Barr virus with type III latency (LMP1+, EBNA2+). The last feature supports the hypothesis that the lymphoma has arisen in a setting of 'local immunodeficiency' as a result of long-standing chronic inflammation in an enclosed space, a characteristic pathogenetic mechanism of diffuse large B-cell lymphoma associated with chronic inflammation. These cases therefore expand the spectrum of this entity to include new clinical scenarios for the development of this lymphoma type.
在长期慢性炎症的背景下发展的弥漫性大 B 细胞淋巴瘤通常与 EBV 相关，通常表现为累及体腔的肿瘤肿块，如脓胸相关淋巴瘤。它在最新的世界卫生组织淋巴瘤分类中被列为一种独特的实体。我们报告了 4 例偶然在组织学检查中发现的病例，分别位于脾假性囊肿、长期性鞘膜积液、心房粘液瘤和金属植入物磨损碎片中。在囊肿内容物或刮除物或心房粘液瘤的基质中发现了散在的不典型（肿瘤性）大淋巴细胞灶。尽管临床情况各异，但所有病例均表现出均质表型：B 细胞标记物（CD20+、CD79a+、PAX5+）阳性、非生发中心免疫表型（CD10-、BCL6-/+、MUM-1+）阳性和 EBV Ⅲ型潜伏（LMP1+、EBNA2+）阳性。最后一个特征支持这样一种假说，即由于封闭空间中的长期慢性炎症导致“局部免疫缺陷”，从而导致淋巴瘤的发生，这是与慢性炎症相关的弥漫性大 B 细胞淋巴瘤的一种特征性发病机制。这些病例因此扩大了该实体的范围，包括这种淋巴瘤类型发生的新临床情况。
