Shi Yun-fei, Li Xiang-hong
Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education); Department of Pathology, Peking University Cancer Hospital & Institute, Beijing 100142, China.
Zhonghua Bing Li Xue Za Zhi. 2013 Apr;42(4):222-6. doi: 10.3760/cma.j.issn.0529-5807.2013.04.003.
To identify the immunohistochemical patterns of follicular dendritic cell (FDC) meshwork and Ki-67 labeling index in small B-cell lymphomas (SBLs) and their significance in differential diagnosis.
Sixty-eight cases of SBLs were included collected from November 2008 to June 2012. The patterns of FDCs and Ki-67 expression were studied on paraffin sections by CD21, CD23 and Ki-67 immunohistochemistry. The characteristic staining patterns of FDCs and Ki-67 expression among different SBLs were analyzed statistically.
The age of SBL patients ranged from 28 to 85 years with a mean of 55.2 years. The male to female ratio was 1.2:1. Fifty-five cases involved only lymph nodes (80.9%), and the remaining cases involved multiple extra-nodal sites. Histological classification of the cases was made according to the 2008 WHO lymphoma classification criteria: 22 were low-grade follicular lymphomas (FLs, including grade 1 and grade 2), 19 marginal zone lymphomas (MZLs), 17 mantle cell lymphomas (MCLs), and 10 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLLs). FDC meshwork limited to the central part of neoplastic follicles was characteristic for FL (90.9%, 20/22). The germinal center FDC meshwork was destroyed primarily at periphery in MZL (14/19). The absence or scattered FDC clusters were typical of SLL/ CLL. Irregular FDC was seen in 7/17 of MCL, while 7/17 MCL displayed FDC pattern similar to that of CLL/SLLs. The pattern of FDCs was a significantly diagnostic feature in distinguishing the four types of SBLs (P < 0.01). Ki-67 was also a statistically significant parameter (P < 0.05) with decreasing labeling index as the following: MCL, FL, SLL and MZL. Ki-67 showed scattered pattern in germinal centers with loss of polarity in FLs. MZL presented uniformly scattered positive pattern in interfollicullar areas. Ki-67 staining was uniform in MCL, but its labeling index varied from 5% to 90%. The Ki-67 index was higher in the morphological "proliferation centers" of all CLL/SLLs.
Immunohistochemical staining patterns of FDC meshworks and Ki-67 labeling index offer a significant discriminatory power in the differential diagnoses among SBLs.
确定小B细胞淋巴瘤（SBLs）中滤泡树突状细胞（FDC）网络的免疫组化模式及Ki-67标记指数，并探讨其在鉴别诊断中的意义。
收集2008年11月至2012年6月期间的68例SBLs病例。采用CD21、CD23和Ki-67免疫组化方法，在石蜡切片上研究FDCs和Ki-67的表达模式。对不同SBLs中FDCs和Ki-67表达的特征性染色模式进行统计学分析。
SBLs患者年龄范围为28至85岁，平均55.2岁。男女比例为1.2:1。55例仅累及淋巴结（80.9%），其余病例累及多个结外部位。根据2008年世界卫生组织淋巴瘤分类标准对病例进行组织学分类：22例为低级别滤泡性淋巴瘤（FLs，包括1级和2级），19例为边缘区淋巴瘤（MZLs），17例为套细胞淋巴瘤（MCLs），10例为慢性淋巴细胞白血病/小淋巴细胞淋巴瘤（CLL/SLLs）。局限于肿瘤滤泡中央部分的FDC网络是FL的特征（90.9%，20/22）。MZL中胚中心FDC网络主要在周边被破坏（14/19）。SLL/CLL的典型表现是FDC缺失或呈散在簇状。17例MCL中有7例可见不规则FDC，而17例MCL中有7例显示与CLL/SLLs相似的FDC模式。FDC模式是区分四种类型SBLs的显著诊断特征（P<0.01）。Ki-67也是一个具有统计学意义的参数（P<0.05），其标记指数按以下顺序递减：MCL、FL、SLL和MZL。Ki-67在FLs的生发中心呈散在模式且极性丧失。MZL在滤泡间区域呈现均匀散在的阳性模式。MCL中Ki-67染色均匀，但其标记指数在5%至90%之间变化。所有CLL/SLLs的形态学“增殖中心”中Ki-67指数较高。
FDC网络的免疫组化染色模式和Ki-67标记指数在SBLs的鉴别诊断中具有显著的鉴别能力。
