Epstein-Barr virus (EBV) in enteropathy-associated T-cell lymphoma (EATL)

A viral map of gastrointestinal cancers

Cancers of the gastrointestinal tract (GIT) are expected to account for approximately 20% of all cancers in 2017. Apart from their high incidence, GIT cancers show high mortality rates, placing these malignancies among the most prominent public health issues of our time. Cancers of the GIT are the result of a complex interplay between host genetic factors and environmental factors and frequently arise in the context of a continued active inflammatory response. Several tumor viruses are able to elicit such chronic inflammatory responses. In fact, several viruses have an impact on GIT tumor initiation and progression, as well as on patients' response to therapy and prognosis, through direct and indirect mechanisms. In this review, we have gathered information on different viruses' rates of infection, viral-driven specific carcinogenesis mechanisms and viral-related impact on the prognosis of cancers of the GIT (specifically in organs that have an interface with the environment - esophagus, stomach, intestines and anus). Overall, while some viral infections show a strong causal relation with specific gastrointestinal cancers, these represent a relatively small fraction of GIT malignancies. Other types of cancer, like Esophageal Squamous Cell Carcinoma, require further studies to confirm the carcinogenic role of some viral agents.

Detection of Active Epstein-Barr Virus Infection in Duodenal Mucosa of Patients With Refractory Celiac Disease

Refractory celiac disease is characterized by mucosal damage in patients with celiac disease despite a gluten-free diet. Little is known about the mechanisms that cause persistent intestinal inflammation in these patients. We performed a case-control study of 17 consecutive patients diagnosed with refractory celiac disease from 2001 through 2014 (median age, 51 y; 10 women) and 24 patients with uncomplicated celiac disease (controls) to determine whether refractory disease is associated with infection by lymphotropic oncogenic viruses. We performed real-time PCR analyses of duodenal biopsy samples from all patients to detect Epstein-Barr virus (EBV), human herpesvirus-8, and human T-cell lymphotropic virus-I, -II, or -III. We used in situ hybridization and immunohistochemical analyses to identify infected cells and viral proteins. We did not detect human herpesvirus-8 or human T-cell lymphotropic viruses in any of the biopsy specimens. However, 12 of 17 (70.5%) biopsy specimens from patients with refractory celiac disease were positive for EBV, compared with 4 of 24 (16.6%) biopsy specimens from controls (P < .001). EBV was detected in inflammatory cells and enterocytes. An analysis of latency- and replication-associated proteins confirmed active infection. Further studies are needed to determine whether EBV infection contributes to the pathogenesis of refractory celiac disease and enteropathy-associated T-cell lymphoma.

Cytotoxic T-cell and NK-cell lymphomas: current questions and controversies

The cytotoxic T-cell and natural killer (NK)-cell lymphomas and related disorders are important but relatively rare lymphoid neoplasms that frequently are a challenge for practicing pathologists. This selective review, based on a meeting of the International Lymphoma Study Group, briefly reviews T-cell and NK-cell development and addresses questions related to the importance of precise cell lineage (αβ-type T cell, γδ T cell, or NK cell), the implications of Epstein-Barr virus infection, the significance of anatomic location including nodal disease, and the question of further categorization of enteropathy-associated T-cell lymphomas. Finally, developments subsequent to the 2008 World Health Organization Classification, including the recognition of indolent NK-cell and T-cell disorders of the gastrointestinal tract are presented.

Epstein-Barr virus and breast cancer: epidemiological and molecular study on Egyptian and Iraqi women

BACKGROUND AND PURPOSE

The role of Epstein-Barr virus (EBV) in breast carcinogenesis is still controversial. Unraveling this relationship is potentially important for better understanding of breast cancer etiology, early detection and possibly prevention of breast cancer. The aim of the current study is to unravel the association between EBV and primary invasive breast cancer (PIBC) in two different Arab populations (Egyptian and Iraqi women).

PATIENTS AND METHODS

The study was done on paraffin-embedded tissues of 40 Egyptian and 50 Iraqi patients with PIBC in addition to 20 normal breast tissues as controls for each group. Both controls and neoplastic tissues were assessed for the expression of EBV genes and proteins (EBNA-1, LMP-1, and EBER) as well as CD21 marker by immunohistochemistry (IHC), in situ hybridization (ISH) and PCR techniques.

RESULTS

Our gold standard for EBV reactivity in breast cancer cases was positivity of both EBNA1 by PCR and EBER by in situ hybridization. EBV was detected in 18/40 (45%) and 14/50 (28%) of Egyptian and Iraqi women; respectively where p=0.073, compared to 0/20 (0%) of their control groups (p<0.05). Regarding the association between EBV positivity and tumor grade, there was not any statistical significant difference between EBV presence and tumor grade in both populations where p=0.860 and p=0.976 and the calculated rank biserial correlation coefficient was 0.114 and 0.269 for Egyptian and Iraqi women respectively.

CONCLUSION

Our findings show that EBV might act as a promoter for the development of PIBC and it might contribute to increased tumor aggressiveness in Egyptian and Iraqi patients.

NK-cell lineage predicts poor survival in primary intestinal NK-cell and T-cell lymphomas

Most primary intestinal natural killer (NK)-cell and T-cell lymphomas (PINKTL) in the Northern Europe are enteropathy-associated T-cell lymphomas, a complication of celiac disease, which is rare in the East. Primary intestinal NK-cell lymphoma is extremely rare and is poorly characterized. We investigated 30 cases of PINKTL from Taiwan with male: female at 2:1, median age at 55.5, 80% with jejunal/ileal involvement, 77% with perforation, 27% with multicentric tumors, and 67% at stage IE. All 7 cases tested for serum IgA anti-tissue transglutaminase were negative. Only 3 (10%) tumors showed enteropathy. Six (20%) were NK-cell lymphoma and 24 (80%) were T-cell lymphoma. The tumor cells in 21/30 (70%) cases were small to medium sized, which correlated with the coexpression of both CD8 and CD56. All tumors expressed at least 1 cytotoxic marker. All 6 NK-cell lymphomas were negative for betaF1, diffusely positive for Epstein-Barr virus-encoded mRNA (EBER), and polyclonal for T-cell receptor gene rearrangement. Five (22%) of the 24 T-cell tumors expressed betaF1, 8 (35%) of the 23 tumors were positive for EBER, and 20 (95%) of the 21 tumors were clonal for T-cell receptor. The overall 1-year survival was 36%. Univariate regression analysis showed that NK-cell lineage, multicentricity, and perforation were associated with poor prognosis. NK-cell lineage (P=0.037) was a poor prognostic factor by multivariate Cox proportional hazard regression analysis. PINKTL in Taiwan is predominantly not enteropathic with a high frequency of perforation, small to medium tumor cell size and cytotoxic phenotype. Primary intestinal NK-cell lymphoma carries a very poor prognosis, and is probably a distinct entity.

Primary gastric T cell lymphoma mimicking marginal zone B cell lymphoma of mucosa-associated lymphoid tissue

Primary gastric T cell lymphoma is rare and mostly of large cell type. In this paper, we present a case of gastric T cell lymphoma morphologically similar to the gastric marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT). Morphologically, the cells are small with abundant clear cytoplasm. Lymphoepithelial lesions are readily identified with diffuse destruction of gastric glands. Immunohistochemically, the neoplastic cells are CD3+/CD4+/CD8−/Granzyme B−. Molecular studies revealed monoclonal T cell receptor γ gene rearrangement. Clinically, the patient responded initially to four cycles of R-CHOP, but then progressed. Because peripheral T cell lymphoma is usually associated with a poor prognosis, whereas marginal zone B cell lymphoma is an indolent lymphoproliferative disorder, this morphologic mimicry should be recognized and completely investigated when atypical small lymphoid infiltrates with lymphoepithelial lesions are encountered in the stomach.

Epstein Barr virus-associated tumours: an update for the attention of the working pathologist

Epstein-Barr virus (EBV) is a herpesvirus associated with approximately 1% of tumours worldwide. EBV is the epitome of B lymphotropic viruses, but the spectrum of tumours it is associated with extends to T lymphocyte and NK cell malignancies, various types of carcinomas and smooth muscle tumours. Ubiquitous EBV infection in humans implies that most individuals carry EBV-infected cells. Therefore, mere detection of the virus in individuals with a tumour is not sufficient for establishing a causal relationship between both events, but instead requires unequivocal detection of viral nucleic acids or viral proteins in the tumour cells. Recent controversies about EBV infection in several carcinomas mainly resulted from such technical issues. The gold standard remains in situ EBER detection, but detection of EBNA1 would be an interesting alternative. EBV detection can be helpful for diagnostic, prognostic and therapeutic purposes. The rate of EBV association with entities such as NK/T cell tumours of the nasal type is so high that absence of detection of the virus in such a lesion should cast doubt of the accuracy of the diagnosis. Similarly, diagnosis of EBV-associated follicular pseudo-tumour obviously requires detection of the virus. EBV-positive common gastric adenocarcinomas seem to have a better prognosis than their EBV-negative counterparts and identification of the virus in B cell lymphoproliferations in immunocompromised individuals will guide therapeutic options. In conclusion, EBV-associated tumours are common enough to be relevant for the pathologist in everyday practice, but there is a need to facilitate detection of the virus (eg EBNA1 antibody).

The value of EUS in predicting the response of gastric mucosa-associated lymphoid tissue lymphoma to Helicobacter pylori eradication

BACKGROUND

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is associated with Helicobacter pylori infection, and regression of the tumor has been described after its eradication.

OBJECTIVE

To determine the value of EUS, in addition to other clinical/endoscopic features, in predicting the response of low-grade MALT lymphoma to H pylori eradication.

DESIGN

A retrospective, single-center study.

SETTING AND PATIENTS

Twenty-two patients with primary gastric MALT lymphoma were identified through a retrospective review of charts of patients seen at the American University of Beirut Medical Center. Only 19 patients with histopathologically confirmed gastric MALT lymphoma and H pylori infection who had EUS staging were included in the study.

MAIN OUTCOME MEASUREMENTS

Regression of the gastric MALT lymphoma as determined by follow-up endoscopy and mucosal biopsies.

RESULTS

Patients with disease restricted to the gastric mucosa had a significantly higher rate of complete remission after H pylori eradication compared with patients who had disease infiltrating into the gastric submucosa (77.8% vs 12.5%, P value .007). There was no statistical difference in terms of the mean follow-up time to achieve such response (P value .212). Age, sex, location of the tumor within the stomach, and endoscopic appearance did not correlate with the probability of complete remission of the MALT lymphoma.

LIMITATIONS

The limitations include a retrospective design and a relatively small sample population.

CONCLUSION

EUS determination of the invasion depth of gastric MALT lymphoma helps predict a complete response to H pylori eradication.

Clinicopathological analysis of T-cell lymphoma in Taiwan according to WHO classification: high incidence of enteropathy-type intestinal T-cell lymphoma

OBJECTIVES

The clinicopathological characteristics of malignant lymphomas vary according to geography, especially for the T-cell lymphoma (TCL). The aim of this study is to demonstrate the incidence and clinicopathological characteristics of TCL in Taiwan according to WHO classification.

METHODS

Archival tissue from 600 malignant lymphomas during the period of 1995-2002 was retrieved, there were 74 cases diagnosed with TCL. Hematoxylin and eosin slides stained and other special studies were reviewed. All cases were reclassified according to the WHO classification. Clinical data, including age, gender, clinical staging, and follow-up, were scrutinized.

RESULTS

There were 52 males and 22 females with male predilectation. The incidence of TCL in malignant lymphoma was 12.3%. The most prevalent histologic subtype was peripheral T-cell lymphoma (PTCL), followed by nasal T-cell/Natural killer- (T-/NK-) cell lymphoma, T-lymphoblastic lymphoma (LBL), anaplastic large cell lymphoma, and enteropathy-type intestinal lymphoma (ETCL). Clinically, 39 cases (49%) had higher clinical stage (III/IV). Overall 2-year and 5-year survival rate was 51.4% and 34.7%, respectively. It was noteworthy that ETCL had high incidence rate (8.1%) and high mortality. There was significant difference in survival rates in respect of clinical stages and histological subtypes.

CONCLUSIONS

TCL is relatively less frequent in Taiwan, compared to other countries in Asian and western countries. The most common histological subtypes are PTCL, unspecified and T-/NK-cell lymphoma. Five-year survival rate is 34.7%. ETCL has higher incidence rate in Taiwan. The clinical stage and histological subtypes are prognostic parameters in determining the survival rates.

Gastrointestinal lymphoma: where morphology meets molecular biology

Primary gastrointestinal lymphomas are best exemplified by mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach and enteropathy-type T-cell lymphoma (ETL). Both lymphomas were initially recognized on morphological grounds and their identification as distinct clinicopathological entities has subsequently been vindicated following integrated immunophenotypic, molecular, and cellular biological investigations. Delineation of the phenotypic, molecular, and biological properties of these lymphomas at various clinicopathological stages of their development has also provided critical information for the clinical management of patients with these diseases. Here, the histopathology and recent advances in phenotypic and molecular characterization of gastric MALT lymphoma and ETL and their applications in diagnosis and clinical management are reviewed.

Loss of heterozygosity at chromosome 9p21 is a frequent finding in enteropathy-type T-cell lymphoma

Enteropathy-type T-cell lymphoma (ETL) and ulcerative jejunitis (UJ) are rare disorders often occurring in patients with coeliac disease. The genetic events associated with the accumulation of intraepithelial lymphocytes in coeliac disease and tumour development are largely unknown. Deletions at chromosome 9p21, which harbours the tumour suppressor genes p14/ARF, p15/INK4b, and p16/INK4a, and 17p13, where p53 is located, are associated with the development and progression of lymphomas. To examine whether deletions at 9p21 and 17p13 play a role in ETL, 22 cases of ETL and seven cases of UJ were screened for loss of heterozygosity (LOH) by tissue microdissection and polymerase chain reaction (PCR) analysis for microsatellite markers. Furthermore, p53 and p16 protein expression was examined by immunohistochemistry. In addition, polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis for detection of mutations in exons 5-8 of the p53 gene was performed in five cases of ETL and three cases of UJ. LOH was found in at least one microsatellite marker at the 9p21 locus in 8 of 22 (36%) ETLs, but not in UJ. Five of nine (56%) tumours composed of large cells showed LOH at 9p21, as opposed to two of eight (25%) tumours with small- or medium-sized cell morphology. The region spanning the p14/p15/p16 gene locus was most frequently affected (five cases); LOH at these markers coincided with loss of p16 protein expression in all of these cases. p53 overexpression was demonstrated in all ETLs examined and in four of seven cases of UJ. However, no alterations of the p53 gene were detected by LOH or PCR-SSCP analysis. The results of this study show that LOH at chromosome 9p21 is frequent in ETL, especially in tumours with large cell morphology; this finding suggests that gene loss at this locus may play a role in the development of ETL.

Peripheral T/NK-cell lymphoma: a report of the IXth Workshop of the European Association for Haematopathology

AIMS

In April 1998, The European Association for Haematopathology organized the IXth workshop on peripheral T-cell and NK-cell lymphomas and leukaemias. The workshop focused on unusual subtypes of these rare malignancies, allowing evaluation of the recently published WHO classification of neoplastic diseases of the lymphoid tissues.

METHODS AND RESULTS

One-hundred and three cases were centrally immunophenotyped and hybridized for EBER1/2 of Epstein--Barr virus. All cases were reviewed by a panel of experienced haematopathologists and classified according to the new WHO classification for lymphoid neoplasms. Three cases were considered as precursor T-cell and 95 cases as peripheral T/NK-cell lymphoma/leukaemia. Although the cases represented a selected series of unusual cases, the following conclusions could be made: (i) Most lymphomas except the hepatosplenic gamma/delta T-cell lymphomas showed a rather broad morphological spectrum, with differences both between and within individual tumours. (ii) This heterogeneity was also reflected by the immunophenotype, for instance a variable expression of CD30 was found in many enteropathy type T-cell lymphomas. (iii) Exceptions in phenotype were regularly found in almost all categories, indicating that phenotype should not be the final determining factor in classification. (iv) The great majority of T-cell lymphomas expressed the alpha/beta T-cell receptor, with the exception of all but one hepatosplenic T-cell lymphomas and a few other extranodal peripheral T cell lymphomas. (v) Malignancies of precursor cells, blastic NK-cell lymphoma/leukaemia, adult T-cell lymphoma/leukaemia and most AIL-type T-cell lymphomas did not express cytotoxic molecules such as TIA1 and granzyme-B. In contrast, all five aggressive NK/T-cell lymphomas/leukaemias, a single case of large granular lymphocyte leukaemia and 40 of 47 primary extranodal lymphoma/leukaemias expressed these molecules. In hepatosplenic gamma/delta T-cell lymphoma, five of six cases showed expression of TIA1 but not of granzyme-B. (vi) Seven tumours developed after organ-transplant, four cases being EBV-positive. No distinct phenotype could be attributed to these cases.

CONCLUSIONS

Most peripheral T/NK cell lymphomas could be categorized as distinct entities as described in the recently proposed WHO classification for lymphoid neoplasms.

Peripheral T-cell lymphoma complicated by a proliferation of large B cells

We studied 14 cases that showed a morphologic appearance of peripheral T-cell lymphoma and contained substantial numbers of CD20+ large B cells. In all but 2 cases, the CD20+ large cells showed a mix of kappa and lambda light chain expression. Two cases showed a focal predominance of kappa expression. In situ hybridization using the EBER1 probe for detection of Epstein-Barr virus (EBV) RNA was performed on every case. EBV RNA was present in 10 cases. Of 8 cases with EBV RNA stained by immunohistochemistry for the latent membrane protein of EBV, 6 were positive. Double-labeling immunohistochemistry and in situ hybridization confirmed that EBV was present in the large B cells. Polymerase chain reaction (PCR) analysis showed a clonal rearrangement of the T-cell receptor (TCR)-gamma chain gene in 12 of 13 cases tested. One additional case showed a clonal rearrangement of the TCR-beta chain gene by Southern blot hybridization. PCR analysis showed a clonal immunoglobulin gene rearrangement in 5 cases, a suggestion of a clonal rearrangement in 1, an oligoclonal pattern in 4, and a polyclonal pattern in 4. The finding of large B and T cells may result in a misdiagnosis of a reactive process or of T-cell-rich B-cell lymphoma. The presence of EBV in some cases could cause further confusion with the reactive T- and B-immunoblastic proliferation of infectious mononucleosis.

Epstein-Barr virus (EBV)-infected cells were frequently but dispersely detected in T-cell lymphomas of various types by in situ hybridization with an RNA probe specific to EBV-specific nuclear antigen 1

Association of Epstein-Barr virus (EBV) with T-cell lymphomas was examined by in situ hybridization (ISH) with an antisense probe specific to abundantly expressed EBV-encoded small RNA-1 (EBER1). In addition to EBER1, EBV-specific nuclear antigen-1 (EBNA-1) is commonly expressed in EBV-associated tumors and latently infected B-lymphocytes. We examined paraffin sections of T-cell lymphomas except those of nasal origin for expression of latent viral transcripts by ISH. Using ISH with improved antisense RNA probe specific to EBNA-1 mRNA, the virus was detected in 19 (59%) of 32 cases, whereas the EBER1 transcript was found in only 15 (47%) of 32 cases by conventional EBER-ISH, resulting in 21 EBV-positive cases (66%) by combining the two methods. Latent membrane protein 1 (LMP1) mRNA of EBV was detected in 15 of 32 cases (47%), while no EBNA2 expression was observed in any these tumors. Patients with these lymphomas positive for LMP1 expression showed lower survival rates than those without expression of the viral mRNA. These results indicate that, in addition to EBER-ISH, RNA-RNA ISH with EBNA1 probes could be useful for detection of EBV-infected cells in paraffin sections, and detection of LMP1 mRNA expression in tumor cells could be a useful prognostic factor for T-cell lymphoma.

Epstein-Barr virus involvement in T-cell malignancy: significance in adult T-cell leukemia

Epstein-Barr virus (EBV) was first reported as the causative virus of Burkitt's lymphoma in 1964. Since then, EBV has also been associated with infectious mononucleosis, AIDS and transplant-related B cell lymphomas, and nasopharyngeal cancer. The virus has further been linked with T cell lymphomas, Hodgkin disease, and NK leukemia or LGL leukemia, establishing a concept of a wide spectrum of EBV associated malignant disorders. EBV DNA encodes several proteins such as EBNA1-6, LMP 1, 2 and others. Recent studies have demonstrated that EBNA2, EBNA5, EBNA3A, EBNA 3C are essential for transformation, and that any gene product is not sufficient to transform cells by itself. Further there are different mechanisms of virus-associated transformation or carcinogenesis among EBV-associated malignant disorders. On the other hand, human T lymphotropic virus type I (HTLV-I) is known as a causative virus of adult T cell leukemia (ATL). However, precise molecular mechanisms of leukemogenesis in ATL still remains unclear. Some additional factors to HTLV-I infection are supposed to be involved in complete leukemogenesis. We demonstrated that HTLV-I infected T cells and primary ATL cells express EBV receptor/CD21 on the cell surface. Therefore, it is possible that EBV infection is one of the factors. We further investigated this possibility in 6 HTLV-I infected T cell lines and primary ATL cells from 18 patients with ATL. However, no EBV genome was detected in both T cell lines and primary ATL cells. EBV involved T-cell lymphoma has unique clinical manifestations as compared to non-EBV involved T-cell lymphoma. Therefore, it is still possible that a small group of ATL patients with unique clinical manifestations is associated with EBV.

A20 RNA expression is associated with undifferentiated nasopharyngeal carcinoma and poorly differentiated head and neck squamous cell carcinoma

A20 is an anti-apoptotic gene that can be induced in human epithelial cell lines in response to expression of the Epstein-Barr virus (EBV) gene product latent membrane protein 1 (LMP1). EBV is a ubiquitous, persistent human herpesvirus that is consistently associated with undifferentiated nasopharyngeal carcinoma (NPC), in which antigen expression includes LMP1. Consistent with a potential role in the development of NPC, LMP1 has profound effects on epithelial cell growth. A20 may be a key downstream effector of LMP1 in NPC, as LMP1-induced A20 blocks p53-mediated apoptosis in H1299 epithelial cells and most NPCs have wild-type p53. Moreover, the potential role of A20 in the development of epithelial malignancies may extend to tumours not associated with EBV. The purpose of this study was to develop an in situ hybridization assay to assess expression of A20 RNA in undifferentiated NPC and in non-EBV-associated poorly differentiated head and neck squamous cell carcinomas (SCCs) and well-differentiated SCCs of the skin. A20 RNA expression was also examined in normal samples of oral mucosa and skin. Expression of A20 was demonstrated in 76 per cent of undifferentiated NPCs and in 80 per cent of poorly differentiated head and neck SCCs, suggesting a role for A20 in the pathogenesis of these epithelial malignancies. By contrast, A20 RNA was not detected in well-differentiated SCCs of the skin, or in any normal samples of squamous epithelial tissue. The pathway leading to A20 expression in non-EBV-associated poorly differentiated head and neck SCCs is clearly LMP1-independent. LMP1 expression was demonstrated in 29 per cent of NPC biopsies, suggesting an LMP1-independent pathway to A20 induction in undifferentiated NPC.

Primary intestinal non-Hodgkin's lymphoma and Epstein-Barr virus: high frequency of EBV-infection in T-cell lymphomas of Mexican origin

Epstein-Barr virus is universally associated with endemic Burkitt's lymphoma (BL) and undifferentiated nasopharyngeal carcinoma and can be detected in a significant proportion of cases of Hodgkin's disease (HD) and peripheral T-cell lymphoma, but only rarely in sporadic B-NHL. The frequency of EBV-positivity in certain neoplasms shows important geographic variations. Both HD and sporadic BL from Latin America have shown higher rates of EBV-association than cases from Western countries. In T-NHL, the frequency of EBV-positivity is influenced by the site of the primary tumor and the phenotype of the neoplastic cells. Nasal and nasal-type T-NHL, which show a T/NK-cell phenotype with expression of CD56 are virtually always EBV-associated, whereas only a proportion of nodal, gastrointestinal and pulmonary T-NHL are EBV-infected. A recent investigation of primary intestinal lymphomas of Mexican origin demonstrated EBV-positivity in all examined cases of T-NHL and BL and a proportion of other B-NHLs. The presence of EBV was independent of the presence or absence of enteropathy. Two of 6 cases studied showed CD56 expression. The high rate of EBV-positivity independent of histologic subtype is in contrast to the low to intermediate rates of EBV-positivity found in cases of intestinal T-NHL from Western countries and indicates that geographic differences in the frequency of EBV-association of lymphoid neoplasms might also extend to a fraction of peripheral T-cell lymphomas.

Primary intestinal gamma-delta T-cell lymphoma with evidence of Epstein-Barr virus

AIMS

Primary intestinal T-cell lymphomas account for about 5% of all primary gastrointestinal lymphomas and are mostly associated with coeliac disease. They usually express the CD3-associated T-cell receptor alpha/beta heterodimer and HML1, and some are related with Epstein-Barr virus (EBV). As far as we know, the present report describes the first case of primary gamma-delta (gamma delta) EBV-associated intestinal T-cell lymphoma without enteropathy. Only hepatosplenic, nasal and cutaneous gamma delta T-cell lymphomas have previously been described.

METHODS AND RESULTS

Our case concerned a 43-year-old man with no history of coeliac disease, who presented with multifocal small bowel involvement showing high grade T-cell lymphoma with medium sized and large pleomorphic cells and a small pleomorphic T-cell component. Angioinvasion and angiocentricity were occasionally present. Immunohistochemical studies of lymphoma cells showed a T-cell gamma delta phenotype (CD3+, CD2+, TCR delta 1+, V delta 2+ and beta F1-) without expression of CD4, CD8, CD5, or HML1. Most tumour cells were positive for the cytotoxic granular proteins TiA1 and granzyme B. Rearrangement of the TCR gamma chain gene was demonstrated by polymerase chain reaction and in-situ hybridization with EBER probes revealed strong nuclear positivity in virtually all neoplastic cells.

CONCLUSION

We described the first case of primary intestinal gamma delta T-cell lymphoma without enteropathy in which EBV might fulfil a pathogenic role.

Epstein-Barr virus in B-cell lymphomas associated with chronic suppurative inflammation

Chronic antigenic stimulation is considered to play an important role in neoplastic lymphoid transformation. This paper describes three cases of non-Hodgkin lymphomas (NHLs) associated with long-standing chronic suppuration. Two were primary bone lymphomas associated with long-standing chronic osteomyelitis and one was a primary skin lymphoma associated with chronic venous ulcers with a latent period of 13 years. All were diffuse large B-cell lymphomas, with plasmacytoid differentiation in two cases. Epstein-Barr virus (EBV)-encoded RNAs were demonstrated in virtually all tumour cells in all cases by in situ hybridization. Immunohistochemistry revealed EBV-encoded latent membrane protein (LMP)-1 expression in one case and BZLF1 protein expression in all three cases, whilst the EBV-encoded nuclear antigen (EBNA)-2 was not detected. Kaposi's sarcoma-associated herpesvirus (KSHV) sequences were absent in two cases studied. Our cases show similarities with pyothorax-associated pleural lymphomas reported mainly from Japan and recently from France, which are invariably associated with EBV. These findings suggest a causal effect of EBV in the development of this type of lymphoma complicating long-standing chronic suppuration. Localized immunodepression induced by chronic inflammation or immunosuppressive cytokines may favour the clonal proliferation of EBV-infected B cells.

Natural killer-like T-cell lymphoma in the small intestine of a child without evidence of enteropathy

A previously healthy 6-year-old boy developed symptoms of small intestinal obstruction and was found to have a large intraabdominal mass. At laparotomy the mass involved the jejunum and adjacent mesenteric lymph nodes, requiring resection. Microscopic and immunohistochemical studies demonstrated a T-cell non-Hodgkin's lymphoma, confirmed by finding clonal T-cell receptor-beta and -gamma gene rearrangements by Southern blot analysis. The immunophenotype of this lymphoma-CD3+CD4-CD8-CD56+TIA-1+ beta F1(-)-suggests that the tumor cells are cytotoxic natural killer (NK)-like T cells, probably of CD3+CD4-CD8- intraepithelial cell origin. Examination of the adjacent and distal small intestinal mucosa failed to show any significant pathologic change. This case was unusual because intestinal lymphomas in children are usually of B-cell origin and most commonly have small noncleaved cell morphology. Childhood intestinal T-cell lymphomas have not been the focus of specific study but appear to be rare. In adults, intestinal T-cell lymphomas often arise in the background of gluten-sensitive enteropathy (celiac disease). In contrast, this child had peripheral T-cell lymphoma, with NK-like T-cell features, in the small intestine with no clinical or histologic evidence of enteropathy.

Epstein-Barr virus (EBV)-induced CD30+ natural killer cell-type malignancy resembling malignant histiocytosis: malignant transformation in chronic active EBV infection associating hypogammaglobulinemia

A 27-year-old male suffered from Epstein-Barr virus (EBV)-related liver dysfunction with persistent hypogammaglobulinemia. IgG titers to EBV antigens were significantly high, while other hepatitis markers were negative. Liver biopsy disclosed active intralobular inflammation. Two years later, he manifested persistent fever, leukopenia, effusions and hypoproteinemia, and his general condition worsened progressively. The peripheral blood small lymphocytes predominantly expressed natural killer (NK)-like phenotypes (CD2+, CD7+, CD16+, CD56+). Hepatosplenomegaly and marked elevation of serum lactic dehydrogenase were observed. He died of respiratory failure at the age of 29. At autopsy, the liver (2190 g), spleen (860 g), small bowel and mesenteric lymph nodes showed massive infiltration of large atypical lymphoid cells in close association with hemophagocytic histiocytes. Involvement was mildly noted also in the bone marrow, lungs, gall-bladder and kidneys. The atypical cells belonged to CD30+ activated NK-type cells expressing CD2, cytoplasmic CD3 epsilon, CD7, CD45RO, CD56, HLA-DR and HLA-DQ. T cell receptors (TCR), surface CD3, CD4, CD5 and CD8 were not expressed. Epstein-Barr virus-related small nuclear RNA (EBER1) and Epstein-Barr virus-associated nuclear antigen 1 were detected in the nuclei of a significant number of atypical cells, while EBV-related latent membrane protein-1 was negative. EBER1 was also identified in the nuclei of non-neoplastic small lymphocytes at both biopsy and autopsy. Monoclonal integration of the EBV genome into the lymphoma cells was shown by Southern blot analysis. Clonal rearrangement of TCR was undetectable. Roles of chronic active EBV infection in the development of NK cell-type malignancy resembling malignant histiocytosis are discussed.

Clonality analysis in tumours of women by PCR amplification of X-linked genes

Modifications have been made to two polymerase chain reaction (PCR) methods for clonality analysis based on the inactivation patterns of two highly polymorphic X-linked genes encoding the androgen receptor (AR) and monoamine oxidase A (MAOA). These methods have been used to examine the clonal nature of frozen tissues from 42 tumours and 25 non-tumour controls from female subjects. Unbalanced inactivation patterns of the genes, which indicate monoclonality, were frequently observed in tumours of heterozygous (informative) cases (18/35 = 51.4 per cent for the AR gene, 9/30 = 30 per cent for the MAOA gene, and 21/38 = 55.2 per cent for both). Among 23 informative non-tumour controls, only one (4.3 per cent), a reactive lymph node, showed skewing in the AR gene. Successful detection of monoclonality was found to depend on the proportion of tumour cells in the tissues examined. None of the AR or MAOA informative cases containing less than 50 per cent of tumour cells showed imbalance in inactivation patterns. With more than 50 per cent of tumour cells in the samples, 66.6 per cent (18/27) of AR and 39.1 per cent (9/23) of MAOA informative cases showed allelic imbalance, with a combined frequency of 72.4 per cent (21/29) of both genes. Our results demonstrate that the methods described are useful for clonal analysis of tissue samples from female patients.

Primary Non-Hodgkin's Lymphoma of the Intestine: High Prevalence of Epstein-Barr Virus in Mexican Lymphomas as Compared With European Cases

Recent studies in Western European populations have shown that peripheral T-cell non-Hodgkin's lymphomas (T-NHLs) are associated with Epstein-Barr virus (EBV) in a higher percentage than sporadic B-cell NHL (B-NHLs), and that the frequency of EBV-positivity might be influenced by the primary site of the tumor. Because of the geographic differences in EBV expression in Burkitt's lymphoma (BL) and Hodgkin's disease (HD), and the lack of studies of sporadic NHL from developing countries, we decided to survey the presence of EBV in a series of primary intestinal lymphomas from patients in Mexico and in Western Europe, and to analyze whether EBV status is influenced by tumor phenotype, and geographic or ethnic determinants. Paraffin-embedded tissue from 43 primary intestinal NHLs (19 cases from Mexico and 24 from Western Europe) were examined, including 17 high grade B-NHLs, 9 low grade B-NHLs, and 17 T-NHLs; 6 of which were enteropathy associated T-cell lymphomas. The distribution of histologic subtypes was similar in both groups. The presence of EBV was investigated with a combined approach using a nested polymerase chain reaction technique as well as immunohistochemistry for latent membrane protein-1 and in situ hybridization for EBV early RNA transcripts (EBER 1/2) RNAs. The median age of the Mexican patients was significantly lower than the median age of the European patients (32 v 62 years). This difference was most pronounced in patients with T-cell lymphoma (24 v 63 years). EBER-positive tumor cells were detected in 13 of the 43 (30%) cases of primary intestinal lymphoma, including 5 of 26 sporadic B-NHL (3 high grade and 2 low grade), and 8 of 17 T-NHL, all of which were classified as pleomorphic, medium and large cell. The rates of EBV-positivity were markedly different for European and Mexican cases. Whereas 7 of 7 (100%) T-NHL and 5 of 12 (42%) sporadic B-NHL of Mexican origin were EBER-positive, only 1 of 10 T-NHL and 0 of 14 sporadic B-NHL from Europe showed EBER expression in tumor cells. Latent membrane protein was positive in only 2 of 43 cases, 1 of which was an EBER-negative high grade B-NHL from Mexico that showed intact total mRNA in control hybridization. CD30 expression was found in 4 of 8 EBV-positive T-NHL and in none of the EBV-positive B-NHL. In contrast to European cases, intestinal NHLs from Mexico show a very high frequency of EBV-positivity, which is not limited to T-NHL, but includes a significant proportion of B-NHL. This study strongly suggests that similar to HD and probably BL, there are important epidemiologic differences in EBV association in intestinal T-cell NHL between European and Mexican populations. These differences might be the result of environmental factors, for example, earlier contact with childhood viruses on intestinal lymphomagenesis.

HLA antigen expression in enteropathy associated T cell lymphoma

AIMS

To investigate the occurrence of abnormal patterns of HLA-ABC and HLA-DR expression in enteropathy associated T cell lymphoma and to relate such abnormalities to the Epstein Barr virus (EBV) status of the tumours.

METHODS

Eleven enteropathy associated T cell lymphomas were immunostained with HC10 (HLA-ABC heavy chain) and TAL 1B5 (HLA-DR alpha chain) monoclonal antibodies and polyclonal anti-beta 2 microglobulin (beta 2m, the HLA-ABC light chain) antibodies. In situ hybridisation for EBV using EBER probes was performed on all cases.

RESULTS

Tumour cells of two of 11 patients were EBER positive. One of these showed partial, and the other, complete loss of beta 2m. HLA-DR expression was undetectable in both patients. Of the remaining nine EBER negative tumours, two were HLA-ABC heavy chain negative or showed only occasional positive cells and five of nine showed partial or complete loss of the HLA-ABC light chain, beta 2m. Seven of the nine cases were either negative for HLA-DR or showed weak expression in a proportion of tumour cells.

CONCLUSIONS

These data show that low or absent HLA-ABC and HLA-DR antigen expression occurs commonly in enteropathy associated T cell lymphoma. These abnormal patterns of HLA expression may be associated with escape from immune attack which, in a minority of patients, could be directed against EBV antigens.

CD30-positive T cell lymphoma of the intestine, complicating ulcerative colitis

Large cell lymphoma with massive necrosis and a phagocytic reaction (malignant histiocytosis-type lymphoma) occurred multifocally in the small and large intestine of a 52 year old male, who had suffered from ulcerative colitis of a pancolonic type for 2 years. After total colectomy and partial jejunectomy, the tumor recurred repeatedly during the subsequent 3-year period. He died of massive intestinal hemorrhage with mild regional lymph nodal involvement. Surface marker studies disclosed CD4/CD8-double negative and CD30+ T cell features. CD3 was weakly expressed. Epstein-Barr virus infection was not identified. The relationship of this neoplasm with 'enteropathy-associated T cell lymphoma' and intestinal Ki-1 lymphoma is discussed.

Epstein-Barr virus in non-Hodgkin's lymphomas of the upper respiratory tract: association with sinonasal localization and expression of NK and/or T-cell antigens by tumour cells

Fifty-five cases of non-Hodgkin's lymphoma (NHL) of the upper respiratory tract, comprising 27 sinonasal (SN) and 28 Waldeyer's ring (WR) NHL, were investigated for expression of Epstein-Barr virus (EBV)-encoded EBER transcripts and latent membrane protein-1 (LMP-1) by RNA in-situ hybridization (RISH) and immunohistochemistry, respectively. Thirty-two cases were B-cell tumours (10 SNHLs and 22 WRNHLs) and 23 cases expressed natural killer (NK) and/or T-cell antigens (17 SNHLs and 6 WRNHLs). EBER transcripts were detected in tumour cells in 19 lymphomas expressing NK and/or T-cell antigens (16/17 SHNHLs and 3/6 WRNHLs) but in only 2/32 B-NHLs (1/10 SNHLs and 1/22 WRNHLs). LMP-1 expression was found in tumour cells in the 19 EBER-positive tumours expressing NK and/or T-cell antigens but in none of the B-cell lymphomas. All the LMP-1-positive lymphomas expressed the CD30 molecule in tumour cells. These results indicate that in lymphomas of the upper respiratory tract, EBV is strongly associated with sinonasal localization and expression of NK and/or T-cell antigens by tumour cells. EBV can also be detected in some cases of WRNHLs expressing NK and/or T-cell antigens, whereas it is rarely found in B-cell SNHLs and WRNHLs. Furthermore, the detection of the LMP-1 protein in tumour cells in most SNHLs and some WRNHLs expressing NK and/or T-cell antigens, in view of the LMP-1 transforming potential, suggests that EBV may play a role in the pathogenesis of these lymphomas.

Disease in children infected with HIV in Abidjan, Côte d'Ivoire

OBJECTIVE

To document the range of disease in African children infected with HIV.

DESIGN

Necropsy results in consecutive children aged 1 month or more who were HIV positive and in children who were HIV negative for comparison; IgA western blots on serum samples from children under 2 years of age who were positive for HIV-1 to test the validity of routine HIV serology.

SETTING

Largest hospital in Abidjan, Côte d'Ivoire.

SUBJECTS

78 children who were HIV positive and 77 children who were HIV negative on whom a necropsy was performed; their median ages at death were 18 and 21 months respectively. 36 HIV positive children and 29 HIV negative children were 1-14 months old; 42 HIV positive and 48 HIV negative children were > or = 15 months old.

MAIN OUTCOME MEASURES

Cause of death and prevalence of diseases confirmed pathologically.

RESULTS

Respiratory tract infections were more common in HIV positive than in HIV negative children (73 (94%) v 52 (68%); P < 0.05), and were aetiologically heterogeneous. Pneumocystis carinii pneumonia was found in 11 out of 36 (31%) HIV positive children aged < 15 months, but in no HIV negative children. Among older children measles was more common in HIV positive children (8/42 (19%) v 2/48 (4%); P < 0.06). Pyogenic meningitis was present in similar proportions of HIV positive and HIV negative children aged < 15 months (7/36 (19%) and 7/29 (24%)). In HIV positive children tuberculosis (1/78), lymphocytic interstitial pneumonitis (1/78), and HIV encephalitis (2/78) were rare.

CONCLUSIONS

There is greater overlap between diseases associated with HIV infection and other common health problems in African children than there is in adults. Compared with adults, HIV positive children had a high prevalence of P carinii pneumonia and a low prevalence of tuberculosis. Measles, but not malaria, was associated with HIV infection.

Non-Hodgkin's lymphoma, coeliac disease, and Epstein-Barr virus: a study of 13 cases of enteropathy-associated T- and B-cell lymphoma

A group of 166 patients with coeliac disease was followed for a period of up to 25 years. During this time, 17 patients developed intestinal tumours that were diagnosed as lymphoma, of which 15 cases were available for review. Eleven of the lymphomas were of T-cell type (enteropathy-associated T-cell lymphoma, EATL) and two were of B-cell type. Two cases were reclassified as undifferentiated carcinoma. The interval between the diagnosis of enteropathy and the onset of lymphoma varied from less than 2 months in four patients to more than 5 years in seven. Seven of the T-cell and both B-cell lymphomas were investigated for the presence of Epstein-Barr virus (EBV) by in situ hybridization (ISH) using probes against Epstein-Barr virus-encoded RNAs (EBERs) and by immunohistochemistry with EBV-specific monoclonal antibodies. All EATL cases were negative, suggesting that EBV is not an important factor in these cases. In one of the B-cell cases, EBV was detectable by ISH and immunohistochemistry in most tumour cells in the mesenteric lymph nodes, but not in any of the tumour cells in the primary ileal tumour, indicating that in this case EBV infection was a late event in the neoplastic process. These results show that lymphoma may develop any time after the onset of coeliac disease and that in our cases of EATL, EBV was not an important factor. In some cases of EBV-related neoplasia, virus infection may be a late event.

Nasal T-cell lymphoma: a clinicopathological and immunophenotypic analysis of 13 cases

Thirteen cases of nasal lymphomas with T-cell or natural killer (NK)-cell phenotype were studied, with attention to clinical presentation and follow-up, the presence of Epstein-Barr virus (EBV) using in situ hybridization (EBER), the immunophenotype, and the presence of cytotoxic granules. All but two patients presented with stage I disease. In three cases local progression resulted in involvement of the central nervous system. When dissemination occurred, this was predominantly to extranodal localizations, in two cases to the skin. Response to therapy was highly variable, but patients treated with radiotherapy with or without additional chemotherapy had a better prognosis than patients treated with initial chemotherapy alone. All lymphomas were associated with EBV, and most cases showed cytotoxic features, ten of which were CD56 positive. In eight cases a T-cell origin was proven, but in five cases a possible NK-cell origin could not be excluded. No clinical differences were seen between true T-cell lymphomas and possible NK-cell neoplasms. Nasal T-cell lymphomas should be considered as a distinct clinicopathological entity, strongly associated with EBV, and with cytotoxic features in most cases. No prognostic parameters were detected to predict dissemination and response to therapy.

Epstein-Barr virus (EBV) in extranodal T-cell non-Hodgkin's lymphomas (T-NHL). Identification of nasal T-NHL as a distinct clinicopathological entity associated with EBV

T-cell Non-Hodgkin's lymphomas (T-NHL) can be defined as clonal malignant proliferations related phenotypically and functionally to normal T-cell populations of the lymphoid tissue. There is increasing evidence that T-NHL with similar morphology but originating from different sites differ in their clinical behaviour, immunophenotypic features, oncogene expression and relation with oncogenic viruses such as HTLV-I and EBV. Indeed, it has been shown that the prevalence of EBV in T-NHL is related to the site of origin. Thus, EBV was found in nearly all nasal T-NHL but only in a proportion of primary nodal, lung, gastrointestinal and Waldeyer's ring T-NHL while it was undetectable in most primary cutaneous T-NHL. Besides their constant association with EBV, nasal T-NHL display peculiar clinical, histological, immunophenotypic and genotypic features. They present clinically as lethal midline granuloma and histologically as pleomorphic malignant tumours variably associated with angiocentricity, angioinvasion and necrosis. Moreover, they frequently exhibit extensive loss of T-cell antigens, including CD3 and TCR alpha beta and gamma delta proteins, usually express the Natural Killer (NK)-related CD56 antigen and frequently show absence of clonal rearrangements of TCR beta, gamma and delta loci. Therefore, among T-NHL, nasal T-NHL can be regarded as a distinct clinicopathologic entity associated with EBV, which could be derived either from immature T-cells or from NK cells.

Mycosis fungoides: expression of C-myc p62 p53, bcl-2 and PCNA proteins and absence of association with Epstein-Barr virus

The expression of C-myc p62, bcl-2, p53, PCNA and EBV-encoded LMP-1 proteins was studied by immunohistochemistry on paraffin-embedded skin specimens from 14 patients with early stage (premycotic erythema and second stage plaques) mycosis fungoides (MF), 21 patients with advanced stage MF (third stage plaques and tumors), 3 patients with Sezary's syndrome (SS) and 3 patients with pleomorphic medium and large cell cutaneous T-cell lymphomas (PML-CTCL). All 41 cases were also screened for the presence of EBV by using RNA in situ hybridization with EBER 1/2 oligonucleotides. Increased expression of C-myc p62, p53 and PCNA proteins was found in PML-CTCL and advanced stages of MF as compared to early stages of MF. These results suggest a relationship between levels of C-myc p62, p53 and PCNA proteins and aggressiveness of the cutaneous T-cell lymphomas. Furthermore, C-myc p62 and bcl-2 proteins were found to be frequently coexpressed in the present series. In view of the background information from in vitro findings and animal models that cooperation of C-myc and bcl-2 is important for lymphomagenesis, our results suggest that coexpression of these oncogenes may be implicated in the pathogenesis and/or the progression of cutaneous T-cell lymphomas. Neither LMP-1 expression nor EBV EBER l/2 transcripts were detected in our series suggesting that EBV is not involved in the pathogenesis of cutaneous T-cell lymphomas.