bcl-10蛋白异常表达对黏膜相关淋巴组织结外边缘区B细胞淋巴瘤的诊断价值

目的探讨bcl-10蛋白表达对黏膜相关淋巴组织结外边缘区B细胞淋巴瘤（MALT淋巴瘤）的诊断价值。方法收集140例不同部位的MALT淋巴瘤,包括胃38例、眼眶35例、肠16例、皮肤15例、涎腺15例、肺14例、甲状腺3例、其他部位4例。对照：10例扁桃体反应性滤泡增生（RFH）、5例眼眶的淋巴组织增生和143例非MALT淋巴瘤、不同类型的非霍奇金淋巴瘤（NHL）,包括20例NK／T细胞淋巴瘤、20例滤泡性淋巴瘤（FL）、20例间变性大细胞淋巴瘤（ALCL）、20例淋巴结内弥漫大B细胞淋巴瘤（DLBCL）、10例原发胃DLBCL、13例淋巴结边缘区淋巴瘤（NMZL）、12例套细胞淋巴瘤（MCL）、11例脾脏边缘区淋巴瘤（SMZL）、6例血管免疫母细胞性T细胞淋巴瘤（AITL）、6例外周T细胞淋巴瘤（PTCL）、3例B．小淋巴细胞淋巴瘤（B-SLL）、1例淋巴浆细胞性淋巴瘤（LPL）和1例浆细胞瘤。免疫组织化学EnVision法检测bcl-10蛋白;免疫组织化学双标记法检测CD20与bcl-10的共表达。结果在扁桃体RFH中,bel-10蛋白呈中等强度表达于生发中心B细胞质中,套细胞不表达,边缘区细胞和副皮质区T细胞呈弱表达。在眼眶淋巴组织增生中,2例bel-10阴性,3例主要呈淋巴滤泡生发中心B细胞质阳性,与扁桃体RFH的表达类似。在非MALT淋巴瘤的其他类型NHL中,除3例（3／10）原发胃DLBCL呈胞核阳性外,其余均未见胞核表达;在不同NHL中的胞质阳性分别为：结内（12／20）和胃（7／10）DLBCL、FL和ALCL（16／20）、PTCL（5／6）、AILT（6／6）、NMZL（13／13）、SMZL（11／11）、B-SLL（3／3）和浆细胞瘤（1／1）,11例MCL呈胞质可疑阳性,20例NK／T细胞淋巴瘤和1例LPL阴性;在部分淋巴瘤中可见肿瘤性细胞表达而反应性小淋巴细胞不表达：MALT淋巴瘤之bcl-10的总表达率为92．1％（129／140）,其中54．3％（76／140）胞质阳性,37．9％（53／140）胞核阳性;但不同部位之胞核阳性率有所不同。在MALT淋巴瘤中,bcl-10蛋白核强表达最常见于眼眶（25．7％,9／35）;除出现异常bcl-10胞核表达外,约20％有反应性滤泡的病例呈生发中心失表达。双标记显示bcl-10阳性细胞为CD20阳性细胞,但CD20阳性细胞多于bcl-10阳性细胞。结论（1）淋巴细胞增生性病变中bcl-10蛋白普遍表达,细胞质表达可出现在多数NHL和反应性增生中,但在淋巴瘤中呈肿瘤细胞表达而反应性细胞不表达,提示bcl-10异常可能与部分淋巴瘤的形成有关;（2）细胞核内bcl-10异常表达主要见于MALT淋巴瘤;眼眶、肺等部位的胞核强阳性和生发中心阴性的特殊模式,对MALT淋巴瘤的诊断及其与反应性病变的鉴别诊断有一定辅助意义。

Abnormal expression of bcl-10 protein in extranodal marginal zone B cell lymphoma of mucosa-associated lymphoid tissue lymphoma type

OBJECTIVE: To evaluate the diagnostic role of nuclear expression of bcl-10 protein in extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type. METHODS: One hundred and forty cases of MALT lymphoma were collected from Cancer Hospital of Fudan University (including 38 cases from stomach, 35 cases from ocular adnexa, 16 cases from intestine, 15 cases from skin, 15 cases from salivary gland, 14 cases from lung, 3 cases from thyroid and 4 cases from other sites). Ten cases of reactive follicular hyperplasia of tonsil, 5 cases of reactive lymphoid hyperplasia of orbit and 143 cases of non-Hodgkin's lymphoma other than MALT lymphoma (including 20 cases of NK/T cell lymphoma, 20 cases of follicular lymphomas, 20 cases of anaplastic large cell lymphomas, 20 cases of nodal diffuse large cell B-cell lymphoma (DLBCL), 10 cases of gastric diffuse large B-cell lymphoma, 13 cases of nodal marginal zone B-cell lymphoma, 12 cases of mantle cell lymphoma, 11 cases of splenic marginal zone B-cell lymphoma, 6 cases of angioimmunoblastic T-cell lymphoma, 6 cases of peripheral T-cell lymphoma, not otherwise specified, 3 cases of small lymphocytic lymphoma, 1 case of lymphoplasmacytic lymphoma and 1 case of plasmacytoma were used as controls. Immunohistochemical study for bcl-10, as well as dual staining with CD20, was performed by EnVision method in paraffin sections. RESULTS: In reactive follicular hyperplasia of tonsil, bcl-10 was moderately or strongly expressed in the cytoplasm of germinal center B cells, while the mantle cells were negative and the marginal zone cells and paracortical T cells showed weak staining. In the 5 cases of reactive lymphoid hyperplasia of orbit, 2 were bcl-10-negative and the remaining 3 expressed bcl-10 in the cytoplasm of germinal center B cells. As for non-MALT lymphomas, 3 gastric DLBCL showed nuclear expression. The remaining cases showed variable cytoplasmic staining. In some cases of lymphoma, bcl-10 was expressed in tumor cells but not in reactive lymphoid cells. On the other hand, 92.1% (129/140) of MALT lymphoma were bcl-10 positive. Among those cases, 54.3% (76/140) showed cytoplasmic positivity and 37.9% (53/140) showed nuclear positivity. The nuclear positivity rate of bcl-10 in different anatomic sites was different. The staining was most intense in MALT lymphoma of ocular adnexa. Dual staining with CD20 showed that the bcl-10-positive cells were also CD20-positive, though the number of bcl-10-positive cells were less than that of CD20-positive cells. CONCLUSIONS: Bcl-10 expression in lymphoid hyperplasia is a universal phenomenon. Cytoplasmic expression of bcl-10 is seen in many different kinds of non-Hodgkin's lymphoma and reactive lymphoid conditions. In some cases of lymphoma, bcl-10 is expressed in tumor cells but not in reactive lymphoid cells, suggesting a possible role of abnormal bcl-10 expression in tumorgenesis. Nuclear expression of bcl-10 is seen mainly in MALT lymphoma, especially when occurring in ocular adnexa and lung. This is in contrast to loss of bcl-10 expression in residual germinal center cells.