Variability in immunophenotype in diffuse large B-cell lymphoma and its clinical relevance

Diffuse large B-cell lymphoma (DLBCL), the single largest category of lymphoma, is a clinically and biologically heterogeneous disease entity. Clinically, patients differ in their mode of presentation and respond variably to therapy. A combination of clinical parameters can be used to predict the patient's response to therapy and survival. The pathological variability of DLBCL is expressed in morphology, immunophenotype, cytogenetic and molecular genetic features. Numerous markers detectable by immunohistochemistry and linked to different aspects of tumour biology have been studied in DLBCL, including lineage-associated and immune markers, proliferation and apoptosis markers, cell adhesion molecules, and more recently stage-specific markers of B-cell differentiation. This review summarizes these studies in regard to their clinical significance and in the light of recent advances in our understanding of the molecular pathology and histogenesis of DLBCL.     

结内外弥漫性大B细胞淋巴瘤的免疫表型和分化特征及预后的比较

目的探讨弥漫性大B细胞淋巴瘤（DLBCL）的临床生物学特征和预后并比较结内与结外的差异。方法分析142例DLBCL的临床病理资料,结内90例,结外52例（胃肠30例,其他22例）,并随访2～108个月,制备组织芯片,并经免疫组织化学EnVision法染色,观察CD10、bcl-6、MUM1蛋白的表达并进一步区分其生发中心B细胞（GCB细胞）和非生发中心B细胞的分化特征。结果胃肠道DLBCL常为Ⅰ～Ⅱ期,国际预后指标评分低,预后也好于结内及其他结外DLBCL。单个抗原的表达率,CD10为19％（27例）,bcl-6为51％（72例）,MUM1为58％（82例）。36％（51例）的DLBCL显示GCB细胞分化特征,64％（91例）的DLBCL显示非GCB细胞分化特征。结外DLBCL的bcl-6的表达（63％）高于结内DLBCL（43％）。在不同的结外部位,甲状腺等部位多见为GCB细胞分化的DLBCL;睾丸等部位多见为非GCB细胞分化的DLBCL。结论DLBCL显示生发中心B细胞和非生发中心B细胞分化特征,结内外以及结外不同部位的DLBCL有着不同的生物学特征和预后。     

PKC-beta II expression has prognostic impact in nodal diffuse large B-cell lymphoma.

Recent studies of gene expression and immunohistochemistry have shown that protein kinase C-beta II (PKC-beta II) might have prognostic significance in patients with diffuse large B-cell lymphoma (DLBCL). We sought to determine the prognostic significance of the expression of PKC-beta II in patients with nodal DLBCL. Formalin-fixed, paraffin-embedded tissues were stained with a monoclonal antibody to PKC-beta II protein. A total of 125 patients were studied; 83 patients (66%) were in the low-risk International Prognostic Index (IPI) group. Forty-eight patients (38%) were positive for PKC-beta II. Complete remission was obtained in 70%, and was not influenced by the PKC-beta II status (67 vs 71%). The 5-year event-free survival (EFS) was worse in high-risk patients (14 vs 58%, P<0.001) and in those with PKC-beta II positivity (36 vs 49%, P=0.054). In low-risk IPI patients, PKC-beta II expression was related to a worse 5-year overall survival (OS) (60 vs 76%, P=0.033) and a worse 5-year EFS (48 vs 66%, P=0.014). In a Cox regression analysis for EFS, both PKC-beta II expression (hazard ratio=1.68, P=0.037) and the IPI (HR=3.07, P<0.001) were independent poor prognostic factors. PKC-beta II (HR=1.72, P=0.046) and the IPI (HR=5.16, P<0.001) were also independent poor prognostic factors for the OS. PKC-beta II expression, along with the IPI, were associated with a worse EFS and OS in patients with nodal DLBCL specially in low-risk IPI patients.     

The aberrancy of immunophenotype and immunoglobulin status as indicators of prognosis in B cell diffuse large cell lymphoma.

To assess the prognostic significance of the immunophenotype in diffuse large cell lymphoma (DLCL), 105 DLCL patients were studied between 1978 and 1987 using a panel of 40 monoclonal antibodies applied to frozen tissue. Eighty-three patients were found to have B cell phenotypes, and 20 patients had T cell phenotypes. Focusing on markers relevant to clinical outcome among B cell LCL showed that lack of expression of the pan B antigens Leu14 and Leu16 were correlated with decreased survival (Leu14, P = 0.01; Leu16, P = 0.06; log-rank). HLA-DR activity also showed that lack of expression of this antigen correlated with poor survival (P = 0.004, log-rank). Kappa light chain immunoglobulin lack of expression showed predictive value for decreased survival as well (P = 0.005, log-rank). Multivariate analyses of known clinically important variables and the immune phenotypes confirm that the loss of HLA-DR and B cell aberrancy are independent factors predicting a poor clinical outcome. Losing some B activation/kappa antigens appears to be a broad biologic phenomenon linking surface antigen lack of expression with decreased survival. This suggests that aberrancy of immunophenotype and immunoglobulin status are key predictors of survival in B-LCL.     

Perforation predicts poor prognosis in patients with primary intestinal diffuse large B-cell lymphoma

Aims:  To elucidate the clinicopathological features and prognostic factors of primary intestinal diffuse large B‐cell lymphoma (PI‐DLBL). Methods and results:  Archival tissues from 30 tumours were used for tissue microarray construction, immunohistochemistry and interphase fluorescence in situ hybridization for chromosomal translocation. The M:F ratio was 1.7:1, with a median age of 60 years. The ileum and ileocaecum were most frequently involved (40% each). Fourteen (47%) were at stage I_E disease, 15 (50%) at stage II_E. Five (17%) tumours were perforated at presentation. The tumours expressed Bcl‐6 (73%), MUM1 (70%), Bcl‐2 (67%) and CD10 (23%). Nine (30%) were classified as germinal centre B‐cell (GCB) phenotype and 21 non‐GCB. Eight of 30 (27%), 7/30 (23%) and 2/29 (7%) cases were positive for rearrangements involving IGH, BCL6, and C‐MYC loci, respectively, whereas all cases were negative for BCL2 and CCND1 translocation. Perforation was a poor prognostic indicator, with a hazard ratio of tumour‐related death at 8.75 (P = 0.001). The differentiation antigens, GCB versus non‐GCB phenotype, or lymphoma‐associated translocations were of no prognostic significance. Conclusions:  We found a higher rate of perforation and lower frequency of GCB phenotype in PI‐DLBL in Taiwan compared with other geographical areas; perforation is a poor prognostic indicator.     

Comparative clinicopathological study of primary CNS diffuse large B-cell lymphoma and intravascular large B-cell lymphoma

Primary CNS diffuse large B-cell lymphoma (CNS DLBCL) is confined to the CNS, and constitutes a distinct entity. In the present study a series of 40 Japanese patients with CNS DLBCL who presented with neurological, but not systemic symptoms, was reviewed. Median survival was 18.7 months. CD5, CD10, Bcl-6, MUM-1, and Bcl-2 were positive in 30%, 10%, 84%, 100%, and 93% of patients, respectively. All CD10-negative patients had non-germinal center B-cell type. There was no significant difference in survival among the immunophenotypic subgroups. CNS DLBCL appeared to be homogenous as a group, which prompted the comparison with another distinct extranodal entity, intravascular large B-cell lymphoma (IVLBCL) in Japanese patients. CNS DLBCL patients did not differ in age, sex, or immunophenotype, including CD5 positivity, from IVLBCL patients, but were significantly less likely to have poor prognostic parameters than IVLBCL patients: the international prognostic index score was low or low–intermediate in 86% of CNS DLBCL patients and high or high–intermediate in 98% of IVLBCL patients. Notably, despite this difference, their survival curves almost overlapped. The present study highlights the issue of clinical distinctiveness of aggressive extranodal lymphomas, the peculiar migration and localization of which should be further clarified.     

弥漫性大B细胞淋巴瘤中hENT1的表达及意义

目的 探讨hENT1在生发中心B细胞(germinal center B cell-like,GCB)型与非GCB(non-GCB)型弥漫性大B细胞淋巴瘤(diffuse large B-cell lymphoma,DLBCL)中的表达及意义.方法 采用免疫组化PV 6000两步法检测CD10、BCL-6、MUM1蛋白在DLBCL的表达并对DLBCL进行亚型分类,同时检测hENT1蛋白的表达,探讨免疫组化染色结果和临床病理参数及预后的关系.结果 (1)hENT1蛋白在DLBCL的GCB及non-GCB亚型中表达差异有显著性(P=0.031,P<0.05).(2)hENT1的表达与患者性别、年龄、部位、LDH高低、Ann Arbor分期、有无B症状的差异均无统计学意义.(3)对76例DLBCL患者进行生存分析,中位随访时间21个月.Log-rank检验GCB/non-GCB组累计生存率差异有统计学意义(P=0.010).结论 DLBCL中non-GCB型患者比例较大,预后差.在治疗过程中,检测hENT1的表达为能否使用核苷类药物提供依据.     

弥漫性大B细胞淋巴瘤500例构成比及免疫表型分析

目的 按照WHO(2008版)造血与淋巴组织肿瘤分类,分析弥漫性大B细胞淋巴瘤(DLBCL)各亚型的构成比情况、免疫表型特点,及其总体生存率.方法 按照新分类,结合形态学观察,利用免疫组织化学、基因重排、原位杂交、荧光原位杂交(FISH)等技术对500例DLBCL,进行回顾性分析和归类,收集随访资料,并对生发中心B细胞(GCB)型和非GCB型组之间、老年人EB病毒(EBV)阳性的DCBCL亚型和非特殊型弥漫性大B细胞淋巴瘤(DLBCL-NOS)之间进行总体生存率比较.结果 500例中DLBCL-NOS约占77.2%(386/500),其次是老年人EBV阳性的DLBCL占9.4%(47/500),然后依次是原发中枢神经系统的DLBCL(4.4%,22/500)、原发纵隔(胸腺)的大B细胞淋巴瘤(2.8%,14/500)、富于T细胞/组织细胞的大B细胞淋巴瘤(2.6%,13/500),其余类型均属于比较罕见的.DLBCL-NOS按照形态学分类以中心母细胞性最为常见,约占95.1%(367/386);按免疫组织化学分型,非GCB型组在DLBCL-NOS中约占68.5%(219/320),GCB型组占28.4%(91/320),而CD5阳性DLBCL仅占3.1%(10/320).总体生存率比较,GCB型组和非GCB型组总体生存率差异无统计学意义(P=0.93),老年人EBV阳性的DLBCL组总体生存率与年龄匹配前、后的DLBCL-NOS组差异均无统计学意义(P值分别为0.13和0.28).对形态学表现为灰区的淋巴瘤病例进行FISH检测,发现了1例"双打击"(double-hit)淋巴瘤.结论 DLBCL-NOS在DLBCL中占绝大多数,其次是老年人EBV阳性的DLBCL和原发中枢神经系统的DLBCL,其他类型均属少见或罕见类型.按照Hans分类进行免疫组织化学分型,非GCB型占多数,GCB型和非GCB型分组总体生存率没有显著性差异.老年人EBV阳性的DLBCL组和用年龄匹配前后的DLBCL-NOS组的总体生存率均无显著性差异.

Abstract：

Objective To study the immunophenotype and overall survival of diffuse large B-cell lymphoma (DLBCL) classified according to the 2008 World Health Organization classification of tumors of hematopoietic and lymphoid tissues. Methods Five hundred cases of DLBCL were retrospectively analyzed with histologic review, immunohistochemistry, gene rearrangement study, in situ hybridization and fluorescence in situ hybridization. Follow-up data were collected. The overall survival rates of germinal center B-cell (GCB) and non-germinal center B-cell (non-GCB) subtypes, as well as those of DLBCL, not otherwise specified (NOS) and Epstein-Barr virus (EBV)-positive DLBCL of the elderly, were compared.Results DLBCL-NOS was the commonest subtype which accounted for 77.2% (386/500) of the cases.EBV-positive DLBCL of the elderly, primary DLBCL of central nervous system, primary mediastinal (thymic) large B-cell lymphoma and T cell/histiocyte-rich large B-cell lymphoma accounted for 9. 4%(47/500), 4. 4% (22/500), 2. 8% (14/500) and 2. 6% (13/500), respectively. 68. 5% (219/320) of DLBCL-NOS belonged to non-GCB subtype. The percentage of GCB subtype and CD5-positive subtype were 28.4% (91/320) and 3. 1% (10/320), respectively. Comparison of the overall survival, GCB and non-GCB immunophenotypic groups have no significant difference (P = 0. 93). And the same result in which of the EBV-positive DLBCL of the elderly and DLBCL-NOS group, before and after age matched (P =0. 13 and O. 28, respectively). A double-hit lymphoma was found by FISH detection, which presenting as gray zone lymphoma in morphology. Conclusions By using Hans algorithm, GCB and non-GCB subtypes show no significant difference in overall survival. EBV-positive DLBCL of the elderly and DLBCL-NOS also do not have significant difference in overall survival. Fluorescence in situ hybridization technique is helpful in identification of DLBCL with rare phenotypes.     

Expression of CD68+ tumor-associated macrophages in patients with diffuse large B-cell lymphoma and its relation to prognosis

Tumor-associated macrophages (TAM) have been ascribed both pro- and anti-tumor properties, but the majority of clinical cancer studies have shown that the presence of a high number of TAM is related to poor prognosis, suggesting that TAM predominantly exert pro-tumoral activity. The prognostic role of TAM in patients with diffuse large B-cell lymphoma (DLBCL), however, is so far unknown. Therefore, TAM were immunohistochemically stained with a CD68 antibody in a retrospective, population-based study including 176 DLBCL patients treated with curative intent. With the exception that patients >60 years of age had a larger number of CD68+ cells (1143 vs 1018 cells/mm²; P  = 0.05), no significant differences were found between the number of CD68+ cells and other clinical factors. Similarly, germinal center B-cell (GCB)/non-GCB immunophenotype or low/high Ki-67 percentage were not associated with CD68 expression. Finally, no significant correlation was found between the number of CD68+ cells and progression-free survival ( P  = 0.34) or overall survival ( P  = 0.94). These data indicate that the pro-tumor effect of TAM has limited clinical relevance in DLBCL patients, which could imply that therapeutic strategies aimed at enhancing their anti-tumor activity are of continuous clinical interest.     

Clinical significance of histology and immunophenotype in childhood diffuse large cell lymphoma

To correlate the histologic subtype of diffuse large cell (DLC) lymphoma with immunophenotype, clinical features, and treatment outcome, 88 consecutively diagnosed children with this disease were studied. Of these cases, 42 (48%) were immunoblastic (IB), polymorphous subtype; 17 (19%) IB, plasmacytoid; 8 (9%) IB, clear cell; 6 (7%) IB, not otherwise specified; and 15 (17%) DLC-follicular center cell (DLC-FCC) type. Of 34 cases successfully phenotyped from paraffin sections, 13 were T cell and 9 were B cell; of the remaining cases, 8 were suggestive of T-cell lineage, 3 of B-cell lineage, and 1 of histiocytic differentiation. Although histologic subtype did not correlate with clinical features or outcome, it did correlate with immunophenotype among those cases for which lineage could be unequivocally assigned (5 of 18 IB vs. 4 of 4 DLC cases were B cell; P = 0.02) Immunophenotype was also correlated with stage of disease (11 of 13 T-cell vs. 3 of 9 B-cell cases had stage III-IV disease; P = 0.03). (Stage III includes all primary thoracic tumors; stage IV includes all with central nervous system and/or bone marrow involvement.) Significant prognostic features were clinical stage and era (thus type) of therapy (P less than 0.001). The authors conclude that most cases of large cell non-Hodgkin's lymphoma in children are of IB morphologic type, most frequently of T-cell lineage, and those with T-cell phenotype appeared to have more advanced disease.     

Primary diffuse large B-cell lymphoma of the testis

In this short review, we discuss primary diffuse large B-cell lymphoma of the testis, an entity that is most commonly seen in older patients. The most common clinical presentation is a unilateral testicular mass. Microscopically, the tumor shows diffuse infiltration of lymphocytes between intact seminiferous tubules. Spermatogenic arrest, interstitial fibrosis, and tubular hyalinization are commonly seen. The tumor is positive for B-cell markers by immunohistochemistry. Treatment has traditionally been with orchiectomy and combination chemotherapy; however, only a minority of patients enjoy a prolonged disease-free survival. Differential diagnosis includes seminoma and viral and granulomatous orchitis.     

信号通路在弥漫性大B细胞淋巴瘤发病过程中的作用

弥漫性大B细胞淋巴瘤(DLBCL)是最常见的一种B细胞恶性肿瘤,约占成人非霍奇金淋巴瘤的30%～40%.依据肿瘤细胞起源大致可将DLBCL分为生发中心B细胞型(GCB型)及非生发中心B细胞型(非GCB型).B细胞发育过程中,多种信号通路精确地调控其细胞周期、增殖、分化及凋亡,以达到平衡,确保B细胞的正常发育及成熟.     

弥漫大B细胞淋巴瘤基因表达谱的研究进展

弥漫大B细胞淋巴瘤（DLBCL）是最常见的一类淋巴瘤,占非霍奇金淋巴瘤的30％左右。DLBCL的临床表现、形态学、免疫表型及遗传学特征极具异质性,越来越多的证据表明其可能并不是一个真正独立的病种。最新的WHO淋巴造血组织肿瘤分类列出了DLBCL的一些形态学亚型,但这种形态学分型不仅与预后的关系尚存在争议,而且诊断的可重复性差,所以实际应用价值不大。大多数DLBCL患者经过化学治疗后可以获得缓解,但半数患者仍在短期内复发并死亡。国际预后指数（international prognostic index,IPI）是通过年龄、功能状态、血清乳酸脱氢酶水平、累及结外部位的数量以及肿瘤临床分期等5个临床特征对患者进行评分,具有相当的预后判断价值。     

Primary breast diffuse large B-cell lymphoma shows a non-germinal center B-cell phenotype.

Primary breast diffuse large B-cell lymphoma has a poor prognosis relative to other extranodal diffuse large B-cell lymphoma. Recently, diffuse large B-cell lymphoma has been subclassified as germinal center B-cell-like and nongerminal center B-cell types using tissue microarrays. The 5-year overall survival rate of the germinal center B-cell group is better than that of the nongerminal center B-cell group. To elucidate the reason for which primary breast diffuse large B-cell lymphoma has a poor clinical outcome, we investigated 15 patients with primary breast diffuse large B-cell lymphoma (stage IE; 13 cases, stage IIE; two cases) by immunohistochemistry using various markers including CD10, Bcl-6, MUM1 and MIB-1 and by molecular analysis of the immunoglobulin heavy chain gene variable region. Immunohistochemistry showed 0/15 (positive cases/examined cases) for CD10, 5/15 for Bcl-6, 15/15 for MUM1, 10/15 for Bcl-2, 2/15 for CD5 and 4/15 for CD40. The expression pattern of CD10(-) MUM1(+) in primary breast diffuse large B-cell lymphoma corresponded to the nongerminal center B-cell group. Moreover, the MIB-1 index was distributed from 60 to 95% with a mean of 79%, indicating a high proliferation of the lymphoma cells. The immunoglobulin heavy chain gene variable region of primary breast diffuse large B-cell lymphoma had a mutation frequency of 1-10% (seven cases) and 0-1 additional mutations in ongoing mutation analysis (five cases). Primary breast diffuse large B-cell lymphoma had characteristics of the nongerminal center B-cell group. In conclusion, primary breast diffuse large B-cell lymphoma has a nongerminal center B-cell phenotype and has a high MIB-1 index. These features might therefore be associated with poor prognosis.