Gastric T-cell lymphoma with cytotoxic phenotype

Primary gastric lymphoma usually originates from B cells of mucosa-associated lymphoid tissue (MALT) infected with Helicobacter pylori. When T-cell lymphomas develop in the stomach, they usually occur in association with infection by human T-lymphotropic virus type 1 and gastric involvement of adult T-cell leukemia. Reported herein is a unique and informative case of gastric peripheral T-cell lymphoma with a cytotoxic phenotype that histologically mimicked, and had to be carefully distinguished from, MALT-type B-cell lymphoma. The patient, a 73-year-old woman, underwent a gastric endoscopy examination, and the histological findings suggested MALT-type gastric lymphoma. Analysis of the immunoglobulin heavy chain (IgH) gene and T cell receptor gamma (TCRgamma) gene revealed monoclonal rearrangement of the TCRgamma gene. The tumor cells exhibited mild atypia and immunoreactivity with anti-CD3, anti-CD8, anti-T-cell intracellular antigen-1, antigranzyme B and antiperforin antibodies, but not with anti-CD20, anti-CD10, and anti-CD79a antibodies. The case was finally diagnosed as gastric T-cell lymphoma with cytotoxic phenotype, and this was confirmed after surgical resection. In cases such as this, small biopsy specimens from the stomach should be examined carefully for low grade B-cell-type malignant lymphoma (MALT lymphoma), because sometimes the proliferating B cells can hide the truly malignant T cells, and rearrangement analysis is useful for diagnosing T-cell malignancy.     

肠病相关性T细胞淋巴瘤9例临床病理分析

目的：探讨肠病相关性T细胞淋巴瘤（ enteropathy-associatied T-ce111ymphoma,EATL）的临床病理学特征。方法回顾性分析9例EATL的临床病理学和免疫表型特征,并复习相关文献。结果Ⅰ型EATL主要由中等至较大的肿瘤细胞组成,核圆形或多角形,核仁明显。Ⅱ型EATL瘤细胞形态单一,体积中等或偏小,核圆形、深染,核碎屑和坏死常见。两种类型EATL背景中均可见组织细胞和中性粒细胞等炎症细胞,且肿瘤细胞弥漫表达 CD3、CD43、TIA-1,不表达 CD4、CD5、CD20、CD79a。Ⅱ型EATL弥漫表达CD56和CD8,Ⅰ型EATL不表达CD56和CD8,Ki-67增殖指数均>70%,EBERs原位杂交阴性。7例获得随访资料,其中4例患者术后10个月内死亡,3例患者术后18个月内死亡。结论 EATL是一种罕见的源于肠道上皮内T淋巴细胞的侵袭性淋巴瘤,临床主要表现为长期慢性腹泻、腹痛、发热及腹部包块等症状,部分病例可发生肠穿孔。诊断时需结合临床表现、病理检查及免疫表型。     

Nodal T-cell lymphomas with a T-follicular helper cell phenotype

The discovery and characterisation of T-follicular helper (TFH) cells, a distinct functional subset of T-helper cells has led to the recognition that some peripheral T-cell lymphomas (PTCLs) have a TFH cell immunophenotype. Due to the overlap in clinical, morphological, immunophenotypic and genetic characteristics, the revised 4^th edition to the WHO classification recognises one umbrella category of ‘angioimmunoblastic T-cell lymphoma and other nodal TCLs of TFH cell origin’. This review provides a brief overview of TFH cells with special emphasis on function and phenotype and a more detailed discussion of clinical, morphologic, immunophenotypic and genotypic characteristics of AITL, follicular T-cell lymphoma and nodal PTCL with TFH phenotype which constitute nodal TCLs of TFH origin. Secondary B-cell proliferations (often EBV positive) and features that help differentiate reactive lymphoid hyperplasia and other types of lymphoma, including PTCL, NOS and secondary B-cell lymphomas and classic Hodgkin lymphoma, from nodal TCLs with a TFH phenotype are discussed.     

T-cell lymphomas in adults: a clinicopathological study of eighteen cases

Eighteen cases of adult T-cell lymphoma have been studied with respect to clinical presentation, response to treatment, histology, enzyme histochemistry, immunocytochemistry, and gene rearrangement. Seven cases (39 per cent) presented at extra-nodal sites, and the age range was from 18 to 79. Treatment was with combination chemotherapy in most cases, and 11 of the 18 patients died within the three year follow-up period. The lymphomas were classified morphologically into six types; T-lymphoblastic lymphoma (TLL), angioimmunoblastic lymphadenopathy (AIL)-like T-cell lymphoma, T-zone lymphoma, pleomorphic mixed medium and large cell T-cell lymphoma (PMMLC), pleomorphic large cell T-cell lymphoma (PLC), and monomorphic large cell T-cell lymphoma (MLC). Enzyme histochemistry was found to be of limited value in the identification of T-cell lymphomas. Immunocytochemistry showed a degree of correlation between the immunological profile and morphology, with cases in the PLC and MLC groups showing limited expression of T-cell antigens. Re-arrangement of the beta chain of the T-cell receptor gene was detected in 12 of the 14 cases studied, and all showed germ-line immunoglobulin genes. The study emphasizes the varied morphological and clinical appearances of adult T-cell lymphoma.     

Diagnosis of NK and cytotoxic T-cell disorders: a review

A number of NK- and T-cell lymphomas with diverse clinical, histologic, and immunophenotypic features express one or more cytotoxic markers. Because these lymphomas are rare they can be challenging to diagnose for clinicians and pathologists. Though the common theme among the neoplasms discussed in this review is expression of one or more cytotoxic markers, expression of other markers such as cytoplasmic CD3, EBV-associated molecules, CD56, and CD30 tend to provide more important clues to the correct diagnosis. In this review, we discuss NK- and T-cell lymphomas and highlight certain key features that can aid in arriving at the correct diagnosis of these malignancies.     

Distinction between coeliac disease and refractory sprue: a simple immunohistochemical method

AIMS: We recently showed that refractory sprue is distinct from coeliac disease, the former being characterized by abnormal intraepithelial T-lymphocytes expressing a cytoplasmic CD3 chain (CD3c), lacking CD3 and CD8 surface expression, and showing TCRgamma gene rearrangements. To take advantage of the abnormal phenotype of CD3c + CD8 - intraepithelial lymphocytes (IEL) in refractory sprue we developed a simple method to distinguish coeliac disease from refractory sprue. METHODS AND RESULTS: Comparative immunohistochemical studies using anti-CD3 and anti-CD8 antibodies were applied on paraffin-embedded and frozen biopsy specimens in refractory sprue (n = 6), coeliac disease (n = 10), healthy controls (n = 5) and suspected refractory sprue (n = 6). Comparable results were obtained on fixed and frozen biopsy specimens. In four of the six patients with suspected refractory sprue, abnormal CD3c + CD8 - IEL and TCRgamma gene rearrangements were found, as in refractory sprue; the remaining two patients had normal (CD3 + CD8 +) IEL and no TCRgamma gene rearrangements. Both patients had coeliac disease, as one failed to comply with a gluten-free diet, while the other was a slow responder. CONCLUSION: This simplified immunostaining method using anti-CD3 and anti-CD8 antibodies on paraffin sections can distinguish active coeliac disease from refractory sprue and should prove useful in clinical practice.     

Pathobiology of Epstein-Barr virus-driven peripheral T-cell lymphomas

In the present review, the authors described the pathobiological features of Epstein-Barr virus (EBV)-driven T/natural killer cell-derived malignancies. These rare tumors appear to be quite heterogeneous with regard to both clinical and pathologic features. Nonetheless, some elements, especially regarding the possible role of EBV (ie, genomic predisposition, pathogenesis, pattern of latency), are similar, enforcing the concept of a causative role for the virus. In clinical practice, although definitely rare in Western countries, the tumors are not exceptional; thus, they should be taken into account in the differential diagnosis of T-lymphoproliferative disorders, also considering the need for extremely prompt intervention. The prognosis of such tumors is generally poor using current approaches. A better understanding of their molecular pathogenesis may lead to significant therapeutic improvements. For example, the nuclear factor-KB pathway and platelet-derived growth factor receptor inhibition may represent 2 options to be tested in clinical trials.     

Hepatic cytotoxic T-cell infiltrates in patients with peripheral T-cell proliferative diseases/lymphomas: clinicopathological and molecular analysis

Seventy patients with various types of peripheral T-cell proliferative disease/lymphoma who manifested with prolonged fever, weight loss, anemia, lymphadenopathy, hepatosplenomegaly and elevated serum levels of alkaline phosphatase and/or lactate dehydrogenase were evaluated. Histopathological examination of the livers revealed T-cell infiltration into the hepatic sinusoids and portal tracts. The morphology of the infiltrated T cells varied from mature small lymphocytes to malignant lymphoid cells. The liver pathology was classified into four groups on the basis of cellular atypia. Group A and group B showed mature lymphoid cell infiltration; however, only group B had multiple large areas of hepatocellular necrosis. Group C showed atypical lymphoid cell infiltration and in group D malignant lymphoid cell infiltrates were demonstrated. The majority of the antigenic phenotypes of these T-cell infiltrates were CD3+, CD4-, CD8+, CD20-, CD45RO+, CD56-, CD57-, TIA-1+ and betaF1-. Epstein-Barr virus RNA in the nuclei of the infiltrated T cells was recorded in 38.6% of the patients and was more common in groups C and D. Patients in groups B, C and D had a very poor prognosis, median survival was only 1 month, whereas median survival in group A patients was 36 months. Chemotherapy was not effective in improving survival. Monoclonal band/s of T-cell receptors (TCR) beta and/or gamma gene rearrangements were detected in 88.6% of patients, and DNA-sequence analysis showed high identity to the human TCR germline gene.     

Peripheral T-cell lymphomas: a clinicopathological and immunological study of 10 cases

Diagnosis and classification of T-cell lymphomas is notoriously difficult. Existing classification schemes are insufficient. Some clinicopathologically well defined T-cell lymphomas exist (mycosis fungoides, Sézary's syndrome, and T-lymphoblastic lymphomas) but the remaining tumours, frequently called peripheral T-cell lymphomas, are a heterogeneous group, clinically, morphologically and immunologically. The data on 10 peripheral T-cell lymphomas are presented and compared to data from the literature. Patients were elderly, had a high frequency of extranodal localizations (notably the skin 75%) and had a poor prognosis: five of 10 patients have died, median survival 22 months. Morphologically and immunophenotypically the group is very heterogeneous. The variety of blast cell morphology is emphasized. No correlations were found between immunophenotype and prognosis, or immunophenotype and morphology.     

Frequency of Epstein-Barr virus-specific cytotoxic T lymphocytes in the blood of Southern Chinese blood donors and nasopharyngeal carcinoma patients

Undifferentiated nasopharyngeal carcinoma is very common among Southern Chinese. While most patients have the disease detected and treated early, those who are diagnosed with advanced stages face a poor prognosis. Nasopharyngeal carcinoma is associated with latent Epstein-Barr virus (EBV); it was suggested previously that a cytotoxic T-lymphocyte (CTL)-based therapy targeting EBV proteins may offer a possible new form of treatment for this disease. The most likely target of this treatment is latent membrane protein 2 (LMP2). To define further the preexisting level of anti-EBV immunity in Chinese subjects, the frequency of peripheral blood mononuclear cells (PBMCs) responding to peptide epitopes was determined using an ELISPOT assay in 50 healthy control blood donors and in 26 patients newly diagnosed with nasopharyngeal carcinoma. A total of 7 LMP2, 2 LMP1, 1 EBNA3A, and 1 EBNA3B epitopes were used in a HLA-restricted manner. As reported previously for healthy virus carriers in western countries, it was found that in both groups the strongest responses were to epitopes in the EBNA proteins with weaker responses to the LMP epitopes. It was found that LMP2 epitopes were recognized in a greater percentage of both groups than previously reported, due most likely to the greater sensitivity of the ELISPOT method. However, patients with nasopharyngeal carcinoma demonstrated a weaker response than that displayed by healthy control subjects to several epitopes. The results demonstrate that LMP2 epitopes are recognized widely in an HLA-restricted manner in patients with nasopharyngeal carcinoma and that immunotherapy to boost preexisting immunity to these epitopes may offer a viable method to treat such patients or to protect against recurrence.     

Rearrangement of the T-cell receptor delta chain gene in T-cell lymphomas with a mature phenotype.

The configuration of the T-cell receptor (TCR) delta chain gene was assessed using restriction fragment analysis and the Southern blot technique in 39 T-cell lymphomas with a mature immunophenotype. The TCR delta gene was rearranged in four lymphomas although the gamma/delta TCR was not expressed in two cases studied. The TCR delta gene was the only TCR gene rearranged in two cases. Each lymphoma with TCR delta gene rearrangement had an aberrant T-cell immunophenotype and three cases were of the large cell anaplastic type. The TCR delta gene was deleted in 22 cases and was in the germline configuration in 13 lymphomas. Deletion of the TCR delta gene was characteristic of mycosis fungoides, adult T-cell leukemia/lymphoma (human T cell leukemia-lymphoma virus positive), and Lennert's lymphoma, and was not identified in angiocentric lymphomas. In eight cases with TCR delta deletion, however, a large number of polyclonal (presumably reactive) T cells were present and, in these lymphomas, the authors could not determine if TCR delta gene deletion occurred in the polyclonal T cells, the neoplastic cells, or both cell populations. The authors conclude that the TCR delta gene is usually deleted in mature T-cell lymphomas, as would be expected in alpha/beta TCR T cells. However, TCR delta gene rearrangement is detectable in approximately 10% of cases. Analysis of this locus may be useful diagnostically, as it occasionally may be the only molecular marker of clonality in mature T-cell lymphomas T-cell receptor delta chain gene rearrangement also is found most often in lymphomas of the large cell anaplastic type.     

Soluble HLA class I/CD8 ligation triggers apoptosis in EBV-specific CD8+ cytotoxic T lymphocytes by Fas/Fas-ligand interaction

In the present study, we report that allogeneic soluble HLA class I (sHLA-I) molecules isolated from serum induce apoptosis on EBV-specific CD8⁺ Fas⁺ cytotoxic T lymphocytes (CTL). CTL apoptosis is induced by the binding of sHLA-I molecules to CD8 and its extent depends on the time of incubation with sHLA-I molecules. Apoptosis is triggered by the interaction of Fas⁺ CTL with soluble Fas-ligand, which is released following the binding of sHLA-I antigens to CD8 molecules. These results suggest that sHLA-I molecules may regulate immune responses by inducing apoptosis in virus-specific CTL.     

Selection of Epstein-Barr virus specific cytotoxic T lymphocytes can be performed with B lymphoblastoid cell lines created in serum-free media

Epstein-Barr Virus (EBV)-transformed B lymphoblastoid cell lines (BLCL) are currently used for numerous applications in cellular immunology. Where protocols destined for clinical application are concerned, the final choice of assay is made according to a risk/benefit ratio analysis. In this balance the use of xenogenic or allogenic serum has always been a major concern, as it carries both an infectious and an immunological risk. So far, it is unknown whether serum can be omitted from the entire BLCL selection procedure. In addition, as BLCL have been described as heterogeneous, serum deprivation may affect their antigen-presenting capacity. In the present study, BLCL were generated in the absence or presence of fetal calf serum (referred to as BLCL0 or BLCL(FCS), respectively). Next, in order to assess the antigen-presenting capacity of these cells, we compared the ability of BLCL0 and BLCL(FCS) cells to stimulate the EBV-specific repertoire of the corresponding donor's peripheral blood mononuclear cells in vitro. Our results showed that addition of serum was not essential for BLCL infection and culture, and that as far as we could determine, BLCL0 cells were as effective as BLCL(FCS) in reactivating the EBV-specific T-cell repertoire in vitro. Notably, FCS-specific T-lymphocytes can be detected among the BLCL(FCS)-specific CD4+-CTL. Not only was this latter observation unexpected for an EBV-seropositive donor, but it implied that the BLCL had captured and processed the corresponding FCS-derived solubles antigens; taken together our results emphasized the interest of the possibility to generate BLCL0, both for research and for clinical applications.     

Nodal peripheral T-cell lymphomas correspond to distinct mature T-cell populations

Peripheral T‐cell lymphomas (PTCL) have not been successfully correlated with specific developmental stages of reactive T‐cells. Mature T‐cells pass through distinct stages upon antigen encounter. Naïve T‐cells are CD45RA⁺/CD45R0^?/CD27⁺/CCR7⁺. After antigen contact they replace CD45RA expression with CD45R0. The mature T‐cells differentiate to central memory cells, which retain CD27 and CCR7, or to effector memory cells, which lose expression of both molecules depending on the strength of the antigen interaction. In this study, we evaluated lymph node biopsies from eight PTCL—not otherwise specified (PTCL‐NOS), seven angioimmunoblastic T‐cell lymphomas (AILT), and 15 anaplastic large cell lymphomas (ALCL). Detection of tumour cells with antibodies that recognize specific rearranged T‐cell receptor Vβ segments allowed us to investigate the expression of various differentiation‐associated molecules. Results were analysed by hierarchical cluster analysis. All AILT and ALCL showed a homogeneous effector cell phenotype (CD45RA^?/CD45R0⁺/CD27^?), but differed in the cytotoxic and activation markers expressed. Several (5/8) PTCL‐NOS clustered together; these cases all exhibited a CD4⁺ central memory cell phenotype (CD45RA^?/CD45R0⁺/CD27⁺) and four expressed the lymph node homing receptor CCR7. In conclusion, AILT and ALCL tumour cells correspond to different subsets of effector cells, while a subset of PTCL‐NOS correlates with a non‐effector T‐cell population. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Epstein-Barr virus (EBV) latent membrane protein-1-specific cytotoxic T lymphocytes targeting EBV-carrying natural killer cell malignancies

Epstein-Barr virus (EBV)-encoded latent membrane protein (LMP) 1 is a potential target for immunotherapy of some proportion of Hodgkin's disease cases, nasopharyngeal carcinomas, EBV-associated natural killer (NK)/T lymphomas, and chronic active EBV infection (CAEBV). Since it is unknown whether EBV-infected NK/T cells are susceptible to lysis by LMP1-specific cytotoxic T lymphohcytes (CTL), we here tested the ability of mRNA-transduced antigen-presenting cells (APC) to stimulate rare LMP1-specific CTL. A 43-amino acid N-terminal deletion mutant LMP1 (DeltaLMP1) could be efficiently expressed in dendritic cells and CD40-activated B cells upon mRNA electroporation. DeltaLMP1-expressing APC were found to stimulate LMP1-specific CTL from a healthy donor and a CTL clone recognized a peptide, IIIILIIFI, presented by HLA-A*0206 molecules. Processing and presentation of the antigenic peptide proved dependent on expression of an immunoproteasome subunit, low-molecular-weight protein-7, as confirmed by RNA interference gene silencing. Furthermore, an EBV-infected NK cell line derived from a patient with CAEBV, and another from an NK lymphoma with enforced HLA-A*0206 expression, were specifically lysed by the CTL. Overall, these data suggest that immunotherapy targeting LMP1 in EBV-associated NK lymphomas and CAEBV might serve as an alternative treatment modality.     

Epstein-Barr virus-positive systemic NK/T-cell lymphomas in children: report of six cases

Rodríguez‐Pinilla S M, Barrionuevo C, García J, de los Ángeles M, Pajares R, Casavilca S, Montes J, Martínez A, Montes‐Moreno S, Sánchez L & Piris M Á
(2011) Histopathology  59 , 1183–1193
Epstein–Barr virus‐positive systemic NK/T‐cell lymphomas in children: report of six cases Aims: The World Health Organization lymphoma classification recognizes two different Epstein–Barr virus (EBV)‐positive T‐cell lymphoproliferative disorders of childhood: systemic EBV‐positive T‐cell lymphoproliferative disease of childhood, and hydroa vacciniforme‐like lymphoma, which is more prevalent in Asia and Latin America. The aim of this study was to characterize six cases of paediatric EBV‐positive peripheral T‐cell lymphoma with distinct features. Methods and results: All cases were male, with a median patient age of 9 years (range: 5–17 years). Most of them presented suddenly with fever, weight loss, hepatosplenomegaly, peripheral lymphadenopathy, and high lactate dehydrogenase (LDH) levels. Moreover, gut, lung or soft tissues of the abdominal wall were also affected in four cases. Partial to total replacement of the lymph node by pleomorphic infiltration of atypical neoplastic cells was found in all cases. Vasculitis and geographical areas of necrosis were seen in three and four cases, respectively. Neoplastic cells showed expression of EBV‐encoded RNA, T‐cell markers (CD2 and CD3), and cytotoxic markers (TIA1, granzyme‐B, and perforin). CD56 and T‐cell receptor ‐γ were expressed in one case each. TCR‐BF1, CD4, CD8 and anaplastic lymphoma kinase were negative. In all cases, the disease progressed rapidly, causing death of the patient, with a median survival of 7.1 months (range: 1–13 months). Conclusions: These cases probably represent a solid form of systemic EBV‐positive T‐cell lymphoproliferative disease of childhood, which requires identification and the development of appropriate therapy.     

Phenotyping of T-cell lymphomas in paraffin sections–which antibodies?

Five antibodies, MT1 (CD43), UCHL1 (CD45RO), OPD4, poly-CD3 and beta F1, were assessed for their reactivity with 50 archival cases of T-cell lymphoma in formalin-fixed paraffin-embedded tissue. All cases had been previously characterized as T-cell lymphomas, and the histological types included 14 cases of small cerebriform lymphoma, six cases of angioimmunoblastic lymphadenopathy-like T-cell lymphoma, four cases of T-zone lymphoma, five cases of pleomorphic small cell lymphoma, 12 cases of pleomorphic medium and large cell lymphoma, four cases of anaplastic large cell lymphoma, two cases of T-lymphoblastic lymphoma and three cases of enteropathy-associated T-cell lymphoma. UCHL1 and MT1 showed reactivity with the highest percentage of cases (94 and 86% respectively) but lack absolute specificity for T-cells, especially in high-grade lymphomas. Poly-CD3 is highly specific for T-cells, and stained neoplastic cells in almost 80% of the cases. beta F1 stained the lowest percentage of cases (40%). UCHL1 and poly-CD3 together identified 98% of cases, and this combination is recommended for the diagnosis of T-cell lymphomas in paraffin sections.     

Quantitative analysis of cell-free Epstein-Barr virus DNA in the plasma of patients with peripheral T-cell and NK-cell lymphomas and peripheral T-cell proliferative diseases

BACKGROUND: The level of circulating EBV DNA is a prognostic marker in patients with some EBV-associated malignant diseases. OBJECTIVES: To investigate the presence and nature of Epstein-Barr virus (EBV) DNA in the plasma and to evaluate the correlation of plasma concentrations of EBV DNA with the EBV genomic status in peripheral blood T-cells and neoplastic cells and with the clinical outcome of patients with peripheral T-cell and NK-cell lymphomas (PTCL) and peripheral T-cell proliferative diseases (PTPD). STUDY DESIGN: EBV DNA in the plasma of 45 patients and 45 controls was measured using real-time PCR. The presence of the EBV genome in the isolated peripheral blood lymphocytes (CD3+ and CD3- cells) was analysed by PCR. Detection of EBV-encoded early RNA (EBER) in corresponding tumor tissues was carried out using in situ hybridization. DNase I digestion was applied to plasma samples to detect naked EBV DNA. RESULTS: Cell-free EBV DNA was detected in 32/38 (84%) of PTCL patients and 5/7 (71%) of PTPD patients, but not in the controls. Patients with EBV genome in peripheral blood CD3+ cells and EBV genome (EBER) in the tumor cells, compared to those without these findings, had significantly higher plasma EBV DNA levels. The majority of circulating EBV DNA molecules was naked form. The plasma EBV DNA levels were not related to survival. CONCLUSIONS: The concentration of EBV DNA in the plasma was not a prognostic marker in PTCL and PTPD patients.     

Morphological and immunohistochemical characteristics of T-cell malignant lymphomas in the west of Scotland

Sixteen cases of T-cell malignant lymphoma are described. They represent the experience of a single pathology department in recent years and serve to illustrate several of the reasons why recognition of T-cell differentiation is important in the classification of lymphomas.