Endoscopic and pathologic features of Epstein-Barr virus-associated gastric carcinoma

Epstein-Barr Virus and Clinico-Endoscopic Characteristics of Gastric Remnant Cancers Compared to Proximal Non-Remnant Cancers: A Population-Based Study

Epstein-Barr virus (EBV) is associated with 5-10% of gastric cancers and is recognized as a distinct molecular subtype. EBV positivity is particularly high in gastric remnant cancer (GRC), which may inform the mode of clinical presentation and findings at endoscopy. Most data are from the East, and the question remains how this applies to a Western cohort. We conducted a population-based study in Central Norway, 2001-2016. Patients with GRC (n = 78) and patients with non-GRC proximally located cancer and available tissue for EBV status (n = 116, control group) were identified from the Norwegian Cancer Registry. Relevant data were collected from the individual patient journals. EBV status was assessed using in situ hybridization. The median latency time from the distal gastrectomy to GRC was 37.6 (range 15.7-68.0) years. GRC more often presented with GI bleeding, 31.0% vs. 16.1%, p = 0.017, and at endoscopy more seldom with an ulcer, 19.7% vs. 38.2%, p = 0.012, or a tumour, 40.8% vs. 66.4%, p < 0.001. For GRC, 18.7% were EBV-positive compared to 6.0% among the controls, p = 0.006. EBV status was not associated with patient age, sex, or Lauren histological type. No difference in long-term survival rates between GRC and controls was found or between EBV-positive vs. -negative GRCs. In conclusion, a higher proportion of GRC cases, compared to controls, are EBV positive, indicating different causative factors. The mode of clinical presentation and findings at endoscopy were more subtle in the patients with GRC.

Endoscopic Diagnosis and Therapy for Epstein-Barr Virus-Associated Gastric Cancer

Epstein-Barr-virus-associated gastric cancer (EBVaGC) represents almost 7% of all GC and is a distinct subtype of GC with extreme DNA hypermethylation. EBVaGC is a tumor-infiltrating lymphocyte-rich tumor with little lymph-node metastasis in its early stage and with a relatively favorable prognosis in its advanced stage. Using upper gastrointestinal endoscopy, we recognize EBVaGC as a mainly depressed type with SMT-like protrusion in the upper part of the stomach near the gastric mucosal atrophic border or remnant stomach. The EBVaGC recognition rate of 21.4% with the endoscopic motif is not high, and further progress in endoscopic diagnosis of EBVaGC is needed. As less invasive endoscopic therapy, the extension of the criteria of endoscopic submucosal dissection (ESD) for early EBVaGC with little lymph-node metastasis should be discussed. Endoscopic diagnosis of EBVaGC may be relevant for the selection of patients who could benefit from endoscopic treatment or chemotherapy.

Estimating the Global Burden of Epstein-Barr Virus-Associated Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Evidence suggests that a fraction of new gastric cancer cases may be etiologically associated with Epstein-Barr virus (EBV), a known carcinogenic agent. We aimed to systematically explore the proportion of EBV-positive gastric cancer.

METHODS

We did a systematic review (PROSPERO CRD42020164473) from January 1990 to August 2021. For each country and geographical region with available data, pooled prevalence and corresponding 95% confidence intervals (CIs) of EBV in gastric tumors were calculated for 3 subtypes of gastric adenocarcinoma (conventional adenocarcinoma, lymphoepithelioma-like gastric carcinoma, and remnant/stump carcinoma). For conventional adenocarcinoma, prevalence ratios (PRs) were presented for sex, Lauren's classification, gastric cancer stage, and anatomical location of the stomach.

RESULTS

In 220 eligible studies including over 68,000 cases of conventional gastric adenocarcinoma, EBV prevalence in tumor cells was 7.5% (95% CI, 6.9%-8.1%) and was higher in men compared with women (PR, 2.1; 95% CI, 1.9-2.4), in diffuse type compared with intestinal type (PR, 1.3; 95% CI, 1.1-1.5), and in the proximal region compared with the distal region (PR, 2.5; 95% CI, 2.0-3.1). There was no difference in EBV prevalence by gastric cancer stage. EBV prevalence was 75.9% (95% CI, 62.8%-85.5%) among lymphoepithelioma-like gastric carcinoma and 26.3% (95% CI, 22.2%-32.0%) among remnant or stump carcinoma.

CONCLUSIONS

Assuming a causal association between EBV and gastric cancer, our findings, when applied to the GLOBOCAN 2020 gastric cancer incidence, suggest that primary prevention such as the development of an effective EBV vaccine might prevent 81,000 EBV-associated gastric cancer cases worldwide annually.

Genomic landscape of virus-associated cancers

It has been estimated that 15%-20% of human cancers are attributable to infections, mostly by carcinogenic viruses. The incidence varies worldwide, with a majority affecting developing countries. Here, we present a comparative analysis of virus-positive and virus-negative tumors in nine cancers linked to five viruses. We find that virus-positive tumors occur more frequently in males and show geographical disparities in incidence. Genomic analysis of 1,658 tumors reveals virus-positive tumors exhibit distinct mutation signatures and driver gene mutations and possess a lower somatic mutation burden compared to virus-negative tumors of the same cancer type. For example, compared to the respective virus-negative counterparts, virus-positive cases across different cancer histologies had less often mutations of TP53 and deletions of 9p21.3/ CDKN2 A- CDKN1A ; Epstein-Barr virus-positive (EBV+) gastric cancer had more frequent mutations of EIF4A1 and ARID1A and less marked mismatch repair deficiency signatures; and EBV-positive cHL had fewer somatic genetic lesions of JAK-STAT, NF-κB, PI3K-AKT and HLA-I genes and a less pronounced activity of the aberrant somatic hypermutation signature. In cHL, we also identify germline homozygosity in HLA class I as a potential risk factor for the development of EBV-positive Hodgkin lymphoma. Finally, an analysis of clinical trials of PD-(L)1 inhibitors in four virus-associated cancers suggested an association of viral infection with higher response rate in patients receiving such treatments, which was particularly evident in gastric cancer and head and neck squamous cell carcinoma. These results illustrate the epidemiological, genetic, prognostic, and therapeutic trends across virus-associated malignancies.

Epstein–Barr virus detection in endoscopic submucosal dissection‐proven early gastric cancer with mixed‐type histology

BACKGROUNDS

Early gastric cancer (EGC) with mixed-type histology is a significant risk factor for additional surgery after endoscopic submucosal dissection (ESD). On the other hand, Epstein-Barr virus-associated gastric cancer (EBVaGC) with mixed-type histology is a favorable risk factor with regard to lymph node metastasis.

METHODS

We performed EBV detection in 13 ESD-proven lesions in 13 cases of early gastric cancer with mixed-type histology using EBV-encoded small RNA1 in situ hybridization (EBER1 ISH).

RESULTS

EBVaGC was diagnosed in only one (7.7%) of the tested lesions. That EBVaGC patient underwent surgery and there was no residual lesion and no lymph metastasis. EBVaGC is not frequent in EGC with mixed-type histology.

CONCLUSIONS

EBV testing of gastric biopsy specimens seems not to be useful to predict the mixed-type histology results of ESD. However, EBV testing for ESD specimens of EGC with mixed-type histology is expected to be useful for avoiding excessive additional surgery.

Immune Microenvironment and Immunotherapeutic Management in Virus-Associated Digestive System Tumors

The development of cancer is a multifactorial phenomenon, while it constitutes a major global health problem. Viruses are an important factor that is involved in tumorigenesis and is associated with 12.1% of all cancer cases. Major examples of oncogenic viruses which are closely associated with the digestive system are HBV, HCV, EBV, HPV, JCV, and CMV. EBV, HPV, JCV, and CMV directly cause oncogenesis by expressing oncogenic proteins that are encoded in their genome. In contrast, HBV and HCV are correlated indirectly with carcinogenesis by causing chronic inflammation in the infected organs. In addition, the tumor microenvironment contains various immune cells, endothelial cells, and fibroblasts, as well as several growth factors, cytokines, and other tumor-secreted molecules that play a key role in tumor growth, progression, and migration, while they are closely interrelated with the virus. The presence of T-regulatory and B-regulatory cells in the tumor microenvironment plays an important role in the anti-tumor immune reaction. The tumor immune microenvironments differ in each type of cancer and depend on viral infection. The alterations in the immune microenvironment caused by viruses are also reflected in the effectiveness of immunotherapy. The present review aims at shedding light on the association between viruses and digestive system malignancies, the characteristics of the tumor immune microenvironment that develop, and the possible treatments that can be administered.

Current Immune Checkpoint Inhibitor Genetic Biomarker Exploration in Gastrointestinal Tumors

Simple Summary

Immune checkpoint inhibitors (ICIs) are now incorporated into the management of GI tumors. The heterogenous nature of these tumors, however, reveals a lack of ICI consistency in effectiveness. Certain biomarkers have emerged as being potentially predictive for ICI effectiveness. Our review focuses on these biomarkers while discussing the current limitations with these markers.

Abstract

Immune checkpoint inhibitors have revolutionized cancer management. Some patients with gastrointestinal (GI) tract malignancy have experienced remarkable results. Here, in our review, we discuss predictive/prognostic GI tumor biomarkers that appear to correlate with benefits with this strategy. Remarkable progress has been made in certain subsets of patients including the potential for solid tumor patients to avoid local therapies such as radiation and/or surgery (organ preservation), which come with acute and chronic risks that have historically been the only curable strategies for these GI tumors. These results provide new and exciting strategies for solid tumor management. Unfortunately, immune checkpoint inhibitors can correlate with biomarkers, but benefits occur in a small subset of patients with GI malignancies. Most frequently, immune checkpoint inhibitors fail to induce response in GI malignancies due to the “cold” tumor microenvironment that protects cancer. Translational strategies are needed to develop effective combination strategies and novel biomarkers to overcome the intrinsic resistance.

Multiple Epstein-Barr virus-associated Gastric Cancers Arising in a Patient with Autoimmune Gastritis

Epstein-Barr virus-associated gastric cancer (EBVaGC) has been reported to be associated with chronic inflammation of the gastric epithelium caused by Helicobacter pylori infection. Autoimmune gastritis (AIG) is also believed to increase the risk of carcinogenesis. We herein report a case of multiple EBVaGCs that arose in a patient with AIG, highlighting the potential for multiplicity of this entity. In this case, a total of four metachronous EBVaGCs were found after initial Endoscopic submucosal dissection for EBVaGC, all of which were treated endoscopically. This case demonstrates that patients with AIG should be monitored closely for development of EBVaGC.

Clinicopathological features of Epstein-Barr virus-associated superficial early stage gastric cancer treated with endoscopic submucosal dissection

BACKGROUND

Epstein-Barr virus (EBV) is known to be involved in gastric carcinogenesis. EBV-associated early gastric carcinoma (EBVEGC) has a lower incidence of lymph node involvement and could be an expanded indication for endoscopic submucosal dissection (ESD) treatment.

AIM

To clarify the prevalence and clinicopathological features of EBVEGC.

METHODS

This study reviewed 618 lesions in 519 patients treated with ESD between 2014 and 2016. Tissue microarray sections were subjected to in situ hybridization staining for EBV-encoded small RNA transcripts (EBER). Lesions positive for EBER were compared with control lesions and were retrospectively analyzed.

RESULTS

12 (1.9%) of the 618 lesions were EBVEGC. EBVEGCs were more frequently located near the atrophic border than control lesions in the middle or upper stomach and were reddish. EBVEGC invasion was deeper and more often histologically undifferentiated. On narrow-band imaging magnifying endoscopy, the EBVEGC group significantly more often showed an endoscopic lace pattern, defined as an absent or obscure microsurface pattern and a microvascular pattern of a tiny, dense, and irregular subepithelial capillary network. The rate of curative resection was significantly lower in the EBVEGC group.

CONCLUSIONS

Only 1.9% of the ESD specimens were EBV-positive. Endoscopic features could raise clinical suspicion of EBV infection.

The New Era of Immunotherapy in Gastric Cancer

Simple Summary

Advanced gastric cancer remains a malignancy with a poor prognosis, with a median survival of about 12–15 months. In recent years, immune checkpoint inhibitors have emerged as a new standard of care for several malignancies, including advanced gastric cancer, and have demonstrated good clinical benefit in some populations. In this review paper, we describe the current status of immunotherapy in gastric cancer, with a focus on molecular and immunological profiles, biomarkers, major clinical trials, and novel immunotherapies.

Abstract

Immune checkpoint inhibitors (ICIs) such as anti-programmed cell death-1 (PD-1) or programmed cell death ligand-1 (PD-L1) monoclonal antibodies have prolonged survival in various types of malignancies, including advanced gastric cancer (AGC). Nivolumab, a monoclonal anti-PD-1 antibody, showed an improvement in overall survival at a later-line therapy in unselected AGC patients in the ATTRACTION-2 study or in combination with chemotherapy as first-line therapy in the global CheckMate-649 study. Another monoclonal anti-PD-1 antibody, pembrolizumab, showed single agent activity in tumors with high microsatellite instability or high tumor mutational burden. Furthermore, a recent KEYNOTE-811 study demonstrated significant improvement in response rate with pembrolizumab combined with trastuzumab and chemotherapy for HER2-positive AGC. Based on these results, ICIs are now incorporated into standard treatment for AGC patients. As a result of pivotal clinical trials, three anti-PD-1 antibodies were approved for AGC: nivolumab combined with chemotherapy as first-line treatment or nivolumab monotherapy as third- or later-line treatment in Asian countries; pembrolizumab for previously treated microsatellite instability-high (MSI-H) or tumor mutational burden-high AGC, or pembrolizumab combined with trastuzumab and chemotherapy for HER2-positive AGC in the United States; and dostarlimab for previously treated MSI-H AGC in the United States. However, a substantial number of patients have showed resistance to ICIs, highlighting the importance of the better selection of patients or further combined immunotherapy. This review focused on molecular and immunological profiles, pivotal clinical trials of ICIs with related biomarkers, and investigational immunotherapy for AGC.

A case of Epstein Barr virus-associated primary squamous cell carcinoma of stomach

Background

Primary squamous cell carcinoma (SCC) of stomach is extremely rare. The pathogenesis of SCC of stomach remains unclear. There is only one report that Epstein Barr virus (EBV) infection may be involved in the pathogenesis of SCC arising in the stomach ever before. Here, we report a case of Epstein Barr virus infection-associated primary SCC of stomach in a 70-year-old woman. She was presented to the referring hospital with hematemesis. Initial endoscopy revealed a bleeding gastric ulcer in the upper part of gastric corpus and the coagulation therapy was followed. After a 3-month follow-up, endoscopy revealed a submucosal tumor-like protrusion instead of an ulcer. Computed tomography revealed a mass in the upper part of stomach and swollen lymph nodes along with the lesser curvature and para-aortic lymph node. Biopsy could not confirm the definitive diagnosis. We performed total gastrectomy with para-aortic lymph node sampling. Histological analysis revealed squamous cell carcinoma with EBV infection with lymph node metastases. Tumor cells were positive for EBV-encoded small RNA (EBER) by in situ hybridization. The postoperative course was uneventful and the patient was discharged on day 11 after the operation. CapeOX was started as adjuvant chemotherapy, and the patient remains alive without recurrence 7 months after surgery.

Conclusion

This is the first case report of EBV infection-associated primary SCC of the stomach diagnosed by in situ hybridization of EBER. EBV infection may be related to the pathogenesis of primary SCC. Further evidence and studies are required to establish optimal strategy for this rare disease.

Biomarker-targeted therapies for advanced-stage gastric and gastro-oesophageal junction cancers: an emerging paradigm

Advances in cancer biology and sequencing technology have enabled the selection of targeted and more effective treatments for individual patients with various types of solid tumour. However, only three molecular biomarkers have thus far been demonstrated to predict a response to targeted therapies in patients with gastric and/or gastro-oesophageal junction (G/GEJ) cancers: HER2 positivity for trastuzumab and trastuzumab deruxtecan, and microsatellite instability (MSI) status and PD-L1 expression for pembrolizumab. Despite this lack of clinically relevant biomarkers, distinct molecular subtypes of G/GEJ cancers have been identified and have informed the development of novel agents, including receptor tyrosine kinase inhibitors and monoclonal antibodies, several of which are currently being tested in ongoing trials. Many of these trials include biomarker stratification, and some include analysis of circulating tumour DNA (ctDNA), which both enables the noninvasive assessment of biomarker expression and provides an indication of the contributions of intratumoural heterogeneity to response and resistance. The results of these studies might help to optimize the selection of patients to receive targeted therapies, thus facilitating precision medicine approaches for patients with G/GEJ cancers. In this Review, we describe the current evidence supporting the use of targeted therapies in patients with G/GEJ cancers and provide guidance on future research directions.

Endoscopic and pathologic motifs for the clinical diagnosis of Epstein–Barr virus‐associated gastric cancer

Objectives

Based on the recent therapeutic trends for gastric cancer (GC), the clinical impact of the diagnosis of Epstein–Barr virus (EBV)‐associated GC (EBVaGC) appears to be important. We retrospectively analyzed endoscopic and pathologic motifs of GC lesions to narrow the number of candidates for EBV testing.

Methods

We performed EBV tests for 32 upper gastrointestinal lesions of 32 patients in the clinical setting. These tests were ordered by endoscopists or by pathologists without an endoscopist's order. EBV‐encoded small RNA1 (EBER1) in situ hybridization was used for the EBV tests. The endoscopic motif for the EBV test was the location in the upper part of the stomach or remnant stomach, mainly the depressed type with a submucosal tumor‐like protrusion of the lesion. The pathologic motif was carcinoma with lymphoid stroma (CLS) or CLS‐like histology of the lesion. We retrospectively analyzed the results of EBV tests for the endoscopic and pathologic motifs.

Results

The final pathological diagnoses of the 32 subjects were 26 GCs including CLS, gastric endocrine cell carcinoma, gastric hepatoid carcinoma, gastric T‐cell lymphoma, gastritis of the remnant stomach, esophageal adenocarcinoma, and esophageal squamous cell carcinoma. When nontypical lesions were excluded, the EBER1‐positive rate was 42.3% (11/26) in GCs. Of the 14 GC lesions ordered examined by endoscopists, three (21.4%) were EBVaGC. Eight of the 12 (66.7%) GCs ordered examined by pathologists were EBVaGC.

Conclusions

The pathologic motif is expected to be useful and the endoscopic motif may be helpful for EBVaGC diagnosis.

Gastric carcinoma with lymphoid stroma diagnosed by endoscopic ultrasound-guided fine-needle aspiration

A 78-year-old man with a subepithelial lesion (SEL) in the gastric body and two carcinomas in the gastric antrum was referred to our hospital. Following a diagnosis of SEL, the patient was followed-up by esophagogastroduodenoscopy annually for 4 years. Although the SEL had increased in size over the years, histological evaluation of the forceps biopsies did not reveal any significant findings. We detected a hypoechoic mass in the submucosa by endoscopic ultrasonography, and suspected the lesion to be an aberrant pancreas or mesenchymal tumor. The patient first underwent endoscopic submucosal dissection for the 2 gastric cancers. Histological examination of the resected specimens revealed intramucosal well-differentiated tubular adenocarcinomas. Next, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was performed for the gastric SEL. Aspirated specimens revealed an adenocarcinoma with lymphocyte infiltration. The lesion was diagnosed as a gastric carcinoma with lymphoid stroma (GCLS). Subsequently, he underwent distal gastrectomy, and the surgical specimen was confirmed as GCLS corresponding to preoperative diagnosis. In addition, the adenocarcinoma cells were positive for Epstein-Barr (EB) virus-encoded small RNA-1 by in situ hybridization. Finally, the lesion was diagnosed as GCLS associated with EB virus. Thus, EUS-FNA is advantageous for diagnosing GCLS associated with EB virus.

Detection of Epstein-Barr Virus DNA in Gastric Biopsies of Pediatric Patients with Dyspepsia

In this study, we assessed the presence of Epstein-Barr virus (EBV) in gastric samples derived from pediatric patients with dyspeptic symptoms, aiming to understand whether EBV participates in the development of early gastric lesions influencing chronic inflammation, in conjunction with the Helicobacter pylori (Hp) bacterium. We analyzed EBV load in 236 gastric biopsies derived from 186 pediatric patients with chronic dyspepsia and compared it with EBV serology, Hp load and serology, and with immune cell infiltration. We found that 7.5% of patients were positive for EBV load, ranging from 240 to 29,685 genomic copies/μg of DNA. Hp genomic sequences were found in 24.7% of patients. EBV positive samples did not correlate with Hp status and were characterized by absent to moderate immune cell infiltration. To our knowledge, this is the first study addressing EBV load in the stomach in a large cohort of pediatric patients with dyspeptic symptoms, providing evidence of EBV localization in the gastric mucosa in early inflammatory lesions. The lack of correlation between EBV and both Hp infection and inflammation is perhaps explained by independent pathogenic mechanisms or because of the randomness of the gastritis sampling. This is also supported by a moderate association between EBV load and serology.

Association between Epstein-Barr virus infection and gastric cancer: a systematic review and meta-analysis

BACKGROUND

Numerous studies conducted over the past 30 years have pointed to the presence of Epstein-Barr virus (EBV) in gastric cancer samples. This study was aimed to provide a meta-analytic review of the prevalence of EBV in gastric cancer patients, and to clarify the relationship between EBV infection and gastric cancer.

METHODS

A literature search was performed electronically using online databases for English language publications until July 1, 2019. The pooled EBV prevalence and 95% confidence intervals (CIs) were estimated using a random-effects model. To determine the association between EBV and gastric cancer, pooled odds ratio (OR) and its 95% CI were computed for case-control studies. Two separate analyses were performed on data from case-control studies with matched and non-match pairs designs to calculate the pooled estimates of ORs.

RESULTS

The pooled prevalence of EBV in 20,361 gastric cancer patients was 8.77% (95% CI: 7.73-9.92%; I² = 83.2%). There were 20 studies with matched pairs design, including tumor and tumor-adjacent normal tissue pairs from 4116 gastric cancer patients. The pooled ORs were 18.56 (95% CI: 15.68-21.97; I² = 55.4%) for studies with matched pairs design and 3.31 (95% CI: 0.95-11.54; I² = 55.0%) for studies with non-matched pairs design. The proportion of EBV-associated gastric cancer among male cases was significantly higher than among female cases (10.83%, vs. 5.72%) (P < 0.0001). However, the pooled OR estimate for EBV-associated gastric cancer was significantly higher among females (21.47; 95% CI: 15.55-29.63; I² = 0%) than in males (14.07; 95% CI: 10.46-18.93; I² = 49.0%) (P = 0.06). EBV was more prevalent in the cardia (12.47%) and the body (11.68%) compared to the antrum (6.29%) (P = 0.0002).

CONCLUSIONS

EBV infection is associated with more than 18 times increase the risk of gastric cancer. Although the prevalence of EBV was higher in male patients than in female patients with gastric cancer, women are more likely than men to develop EBV-associated gastric cancer. Our findings showed that using tumor-adjacent normal tissues as the control group provides more robust and accurate results regarding the relationship between EBV infection and gastric cancer.

Gastric cancer: genome damaged by bugs

Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide. The role of the microorganisms in gastric tumorigenesis attracts much attention in recent years. These microorganisms include bacteria, virus, and fungi. Among them, Helicobacter pylori (H. pylori) infection is by far the most important risk factor for GC development, with special reference to the early-onset cases. H. pylori targets multiple cellular components by utilizing various virulence factors to modulate the host proliferation, apoptosis, migration, and inflammatory response. Epstein–Barr virus (EBV) serves as another major risk factor in gastric carcinogenesis. The virus protein, EBER noncoding RNA, and EBV miRNAs contribute to the tumorigenesis by modulating host genome methylation and gene expression. In this review, we summarized the related reports about the colonized microorganism in the stomach and discussed their specific roles in gastric tumorigenesis. Meanwhile, we highlighted the therapeutic significance of eradicating the microorganisms in GC treatment.

Clinical impact of Epstein-Barr virus status on the incidence of lymph node metastasis in early gastric cancer

Epstein-Barr virus-positive gastric cancer (EBVGC) comprises approximately 9% of all gastric cancers and is associated with a low prevalence of lymph node metastasis (LNM). Given that limited data concerning LNM in EBV-related early GC are available, EBV status is not considered an indicator for endoscopic submucosal dissection (ESD). In this review, we focused on pT1 EBVGC and on gastric carcinoma with lymphoid stroma (GCLS), and discuss expanded ESD indications and curative resection criteria. In pT1b EBVGC, the incidence of LNM was low (6/180 patients, 3.3%; 95% confidence interval [CI] 1.2-7.1), especially in lymphovascular invasion-negative EBVGC (1/109 patients, 0.9%). No patients with pT1a EBVGC had LNM (0/38 patients, 0%; 95% CI 0-7.6), even those who did not meet the current curative ESD criteria. Although the frequency of LNM in GCLS was low (5.0-10.6%), the incidence of LNM in non-EBV GCLS was relatively high (10.0-20.0%); therefore, EBV status can be considered a more important factor than GCLS. In summary, the clinicopathological characteristics of EBVGC differ from those of conventional GC, and EBV negativity is a risk factor for LNM in early GC. Therefore, patients in this group are likely to be promising candidates for ESD, and we recommend that EBV status evaluation be included in early GC treatment guidelines.

Epstein-Barr virus-associated gastric carcinomas developed after successful eradication of Helicobacter pylori

Epstein-Barr virus-associated gastric carcinoma (EBVaGC) can develop in gastric mucosa affected by Helicobacter pylori (H. pylori)-induced atrophic gastritis. However, it is unclear whether EBVaGC can develop in gastric mucosa after successful eradication of H. pylori. We report 3 cases of EBVaGC discovered more than 5 years after successful eradication of H. pylori. All 3 cases are men with a history of smoking. The periods from successful eradication to development of EBVaGC were 18, 8, and 9 years, respectively. Their tumors were mainly depressed lesions located in the gastric corpus. Two patients had intramucosal cancer and the other had advanced gastric cancer. Mucosal atrophy was present in the background gastric mucosa of all of three, and the anti-H. pylori antibody titer in each patient had fallen to < 3 U/mL. These cases indicate that EBVaGC can occur after successful eradication of H. pylori.

Clinicopathologic Characteristics of Epstein-Barr Virus-Associated Gastric Cancer Over the Past Decade in Japan

: Epstein-Barr virus (EBV) is a ubiquitous human herpes virus, but related with several types of malignancies. Among EBV-related malignancies, EBV-associated gastric carcinoma (EBVaGC) has the largest patient's number. We screened for EBV infection in 1067 GC lesions of 1132 patients who underwent surgical resection from 2007 to 2017 in Japan and examined clinicopathological features of EBVaGC. EBV infection was detected by in situ hybridization with EBV-encoded small RNA 1(EBER-1 ISH). EBV was infected in 80 GC lesions (7.1%). Mean age was significantly lower in patients with EBVaGC than with EBV-negative GC. EBVaGC was more frequent in men than in women. EBVaGC was found twice as frequent in the upper or middle stomach as in the lower stomach. Early EBVaGC was more frequent, and submucosally invaded cases were dominant. The presence of lymphatic vessel invasion was less in EBVaGC, but frequency of lymph node metastasis was similar. Carcinoma with lymphoid stroma (CLS) was found in 3.8% (43/1132) of all lesions with 60.5% of EBV positivity. The synchronous or metachronous multiple GC was frequent in EBVaGC. We clarified clinicopathologic characteristics of EBVaGC over the past decade in Japan. EBV infection should be examined in gastric cancer cases showing these characteristics.

Epstein-Barr virus status is a promising biomarker for endoscopic resection in early gastric cancer: proposal of a novel therapeutic strategy

BACKGROUND

Epstein-Barr virus-positive gastric cancer (EBVGC) is associated with a low prevalence of lymph node metastasis (LNM); however, EBV status is not considered in the indication of endoscopic resection (ER). We aimed to clarify the implication of EBV status for ER of pT1b GC.

METHODS

Consecutive cases of pT1b GCs treated with surgery between 2005 and 2014 were retrospectively analyzed. Clinicopathological factors and LNM status were compared between EBVGC and non-EBVGC groups.

RESULTS

EBVGC accounted for 7.9% (71 of 898) cases. Compared to non-EBVGC, EBVGC was more frequent in males (p = 0.0055), the upper third region (p < 0.0001), showed elevated growth features (p = 0.0059), and was associated with a lower frequency of accompanying ulceration (p = 0.002), greater depth of submucosal invasion (p = 0.017), and lower frequency of lymphatic invasion (p < 0.0001). Frequency of LNM was significantly lower in EBVGC than in non-EBVGC (4.2% vs. 21.9%, p < 0.0001). In EBVGC, tumors without lymphovascular invasion showed significantly lower frequency of LNM than those with lymphovascular invasion (0 of 50, 0%; vs 3 of 21, 14.3%; p = 0.023). Histologically, 84.5% (60 of 71) of EBVGC included carcinomas with lymphoid stroma and/or lace pattern components.

CONCLUSIONS

pT1b EBVGC is a convincing candidate for ER, regardless of risk factors other than lymphovascular invasion.

Epstein-Barr Virus-associated Early Gastric Cancer Treated with Endoscopic Submucosal Dissection: A Possible Candidate for Extended Criteria of Endoscopic Submucosal Dissection

A 73-year-old man visited our hospital for the treatment of an early gastric cancer (GC) lesion. We performed en bloc resection using endoscopic submucosal dissection (ESD) for his GC lesion. The present GC lesion was Epstein-Barr virus (EBV)-associated poorly differentiated-type adenocarcinoma invading into the submucosal layer. Recently, accumulating data has shown that the risk of lymph node metastasis from early EBV GC without local lymphovascular infiltration is low. The present patient has been in good health for over three years since ESD. Some cases of early EBV GC with invasion into the submucosal layer may be candidates for further extension of the ESD criteria.

Epstein-Barr virus positivity among surgically resected intramucosal gastric cancer

Epstein-Barr virus-associated gastric cancer (EBV-GC) accounts for approximately 8% of gastric cancers. However, little is known regarding intramucosal EBV-GC. The present study aimed to evaluate endoscopic and clinicopathological characteristics of intramucosal EBV-GC. Pathological data of 172 patients with 173 intramucosal gastric cancers who received gastrectomy with lymph node dissection were obtained for review. EBV-encoded small RNA in situ hybridization (EBER-ISH) was carried out using a tissue microarray block. Eight intramucosal early gastric cancers (4.6%) were EBER-ISH positive in which no cases had any lymph node metastasis. Macroscopic types were either depressed or flat, dominant histology was mixed type of moderate and poorly differentiated adenocarcinoma. In detail, histological features of "lace pattern" or "lymphocyte infiltration into the stroma or cancer nests" were observed.

Clinical Importance of Epstein⁻Barr Virus-Associated Gastric Cancer

Epstein⁻Barr virus-associated gastric carcinoma (EBVaGC) is the most common malignancy caused by EBV infection. EBVaGC has definite histological characteristics similar to gastric carcinoma with lymphoid stroma. Clinically, EBVaGC has a significantly low frequency of lymph node metastasis compared with EBV-negative gastric cancer, resulting in a better prognosis. The Cancer Genome Atlas of gastric adenocarcinomas proposed a molecular classification divided into four molecular subtypes: (1) EBVaGC; (2) microsatellite instability; (3) chromosomal instability; and (4) genomically stable tumors. EBVaGC harbors a DNA methylation phenotype, PD-L1 and PD-L2 overexpression, and frequent alterations in the PIK3CA gene. We review clinical importance of EBVaGC and discuss novel therapeutic applications for EBVaGC.

Unusual growth of an Epstein-Barr virus-associated differentiated early-stage gastric carcinoma: A case report

Epstein-Barr virus (EBV) infection is involved in a subset of gastric carcinoma (GC) cases, and is associated with distinct clinicopathological features. The present study reports a unique case of EBV-associated early-stage GC compared with the other cases experienced in our hospital. A 72-year-old male receiving treatment for cerebral infarction underwent an esophagogastroduodenoscopy (EGD) for suspicion of gastrointestinal bleeding. EGD revealed a type 0-I protruding lesion in the lesser curvature of the upper gastric corpus. Biopsy indicated well-differentiated adenocarcinoma. As the tumor diameter was >3 cm and the thickness of the tumor suggested submucosal invasion, laparoscopic gastrectomy was performed. Histological assessment revealed polypoid growth of an intramucosal, differentiated, tubular or papillary adenocarcinoma, with dense infiltration of lymphocytes. The carcinoma crypts were found to be EBV-positive on in situ hybridization. A review of the clinicopathological features of 25 EBV-associated GCs from 20 patients treated in our hospital between 2005 and 2014 was performed. All of these tumors, except that in the current case, appeared as shallow, depressed or ulcerative lesions. Thus, the current case appears to represent an unusual growth of EBV-positive GC.

Clinical application of early gastric carcinoma with lymphoid stroma based on lymph node metastasis status

BACKGROUND

Gastric carcinoma with lymphoid stroma (GCLS) is characterized by undifferentiated carcinoma mixed with prominent lymphoid infiltration. GCLS has unique clinicopathological features and a better prognosis compared to other types of gastric cancer. We analyzed the clinicopathological features of early GCLS in relation to lymph node metastasis (LNM).

METHODS

We performed a retrospective analysis of 241 patients diagnosed with GCLS confined to the mucosa or the submucosa between March 1998 and December 2015. Their data were compared with those from 1219 patients who underwent resection for differentiated early gastric cancer (EGC).

RESULTS

Of the 241 patients analyzed, 33 (13.7%) had intramucosal cancers and 208 (86.3%) had cancers that penetrated the submucosa. Compared to differentiated EGC, early GCLS was more prevalent in younger individuals and in men, tended to be proximally located, was highly associated with Epstein-Barr virus (EBV) infection (89.2%), and had a lower risk of LNM. The 5-year disease-specific survival rate of patients with early GCLS was 98.3% but depended significantly on LNM status (p < 0.001) and EBV infection status (p = 0.039). The risk of LNM from mucosal GCLS and submucosal GCLS was 0% [95% confidence interval (CI) 0-9.1] and 10% (95% CI 6.8-15.2), respectively. On multivariate analysis, LNM was found to be associated with tumor size (p = 0.022) and lymphovascular invasion (p = 0.002) in addition to tumor depth.

CONCLUSIONS

Early GCLS has distinct clinicopathological features depending on age, sex, tumor location, EBV infection status, and LNM status. Tailored therapies, including endoscopic treatment, are needed based on the distinct clinicopathological features of early GCLS.

Clinicopathologic features of early gastric carcinoma with lymphoid stroma and feasibility of endoscopic submucosal dissection

BACKGROUND

Gastric carcinoma with lymphoid stroma (GCLS) is a rare disease known to have unique features and a favorable prognosis. This study aimed to determine the clinicopathologic features of early GCLS (EGCLS) and define the feasibility of endoscopic submucosal dissection (ESD) for EGCLS.

METHODS

We performed a retrospective analysis of 70 EGCLS patients treated via ESD or surgery and 1626 patients who underwent surgical resection for early non-GCLS (ENGCLS) between January 2007 and December 2014 at Pusan National University Hospital, Busan, Republic of Korea.

RESULTS

The mean age of EGCLS patients was 58 years (range 36-77 years); a male predominance (3.7:1) was observed, and 81.4% showed Epstein-Barr virus positivity. Compared with ENGCLS, EGCLS was macroscopically more elevated (34.3 vs. 18.0%, P = 0.003) and located more proximally (upper third: 37.1 vs. 9.7%, P < 0.001). Tumor size was smaller (2.1 ± 1.1 vs. 3.1 ± 2.0 cm, P < 0.001), but submucosal invasion was more frequent (77.1 vs. 44.4%, P < 0.001) and deeper in the EGCLS group. Among the 59 EGCLS patients who were treated surgically, only two (3.4%) showed lymph node metastasis (LNM). Despite submucosal invasion, EGCLS showed a lower LNM rate (4.0 vs. 19.4%, P = 0.007) than ENGCLS, even in patients with SM3 EGCLS (5.3 vs. 24.5%, P = 0.007). There were no recurrences in the available ten patients who underwent ESD alone during a mean follow-up of 37.2 months.

CONCLUSIONS

In this study, we observed unique clinicopathologic features with a very low LNM rate in EGCLS. We consider ESD a potentially curative treatment strategy for EGCLS despite deep submucosal invasion, especially in patients with poor performance status and significant comorbidities.

Epstein-Barr Virus and Gastric Cancer Risk: A Meta-analysis With Meta-regression of Case-control Studies

Objectives:

Research on how the risk of gastric cancer increases with Epstein-Barr virus (EBV) infection is lacking. In a systematic review that investigated studies published until September 2014, the authors did not calculate the summary odds ratio (SOR) due to heterogeneity across studies. Therefore, we include here additional studies published until October 2015 and conduct a meta-analysis with meta-regression that controls for the heterogeneity among studies.

Methods:

Using the studies selected in the previously published systematic review, we formulated lists of references, cited articles, and related articles provided by PubMed. From the lists, only case-control studies that detected EBV in tissue samples were selected. In order to control for the heterogeneity among studies, subgroup analysis and meta-regression were performed.

Results:

In the 33 case-control results with adjacent non-cancer tissue, the total number of test samples in the case and control groups was 5280 and 4962, respectively. In the 14 case-control results with normal tissue, the total number of test samples in case and control groups was 1393 and 945, respectively. Upon meta-regression, the type of control tissue was found to be a statistically significant variable with regard to heterogeneity. When the control tissue was normal tissue of healthy individuals, the SOR was 3.41 (95% CI, 1.78 to 6.51; I-squared, 65.5%).

Conclusions:

The results of the present study support the argument that EBV infection increases the risk of gastric cancer. In the future, age-matched and sex-matched case-control studies should be conducted.

Epstein-barr virus in gastric carcinoma

The Epstein-Barr virus (EBV) is detected in about 10% of gastric carcinoma cases throughout the world. In EBV-associated gastric carcinoma, all tumor cells harbor the clonal EBV genome. Gastric carcinoma associated with EBV has distinct clinicopathological features, occurs predominately in men and in younger-aged individuals, and presents a generally diffuse histological type. Most cases of EBV-associated gastric carcinoma exhibit a histology rich in lymphocyte infiltration. The immunological reactiveness in the host may represent a relatively preferable prognosis in EBV-positive cases. This fact highlights the important role of EBV in the development of EBV-associated gastric carcinoma. We have clearly proved direct infection of human gastric epithelialcells by EBV. The infection was achieved by using a recombinant EBV. Promotion of growth by EBV infection was observed in the cells. Considerable data suggest that EBV may directly contribute to the development of EBV-associated GC. This tumor-promoting effect seems to involve multiple mechanisms, because EBV affects several host proteins and pathways that normally promote apoptosis and regulate cell proliferation.

Epstein-Barr Virus (EBV)-associated gastric carcinoma

The ubiquitous Epstein-Barr virus (EBV) is associated with several human tumors, which include lymphoid and epithelial malignancies. It is known that EBV persistently infects the memory B cell pool of healthy individuals by activating growth and survival signaling pathways that can contribute to B cell lymphomagenesis. Although the monoclonal proliferation of EBV-infected cells can be observed in epithelial tumors, such as nasopharyngeal carcinoma and EBV-associated gastric carcinoma, the precise role of EBV in the carcinogenic progress is not fully understood. This review features characteristics and current understanding of EBV-associated gastric carcinoma. EBV-associated gastric carcinoma comprises almost 10% of all gastric carcinoma cases and expresses restricted EBV latent genes (Latency I). Firstly, definition, epidemiology, and clinical features are discussed. Then, the route of infection and carcinogenic role of viral genes are presented. Of particular interest, the association with frequent genomic CpG methylation and role of miRNA for carcinogenesis are topically discussed. Finally, the possibility of therapies targeting EBV-associated gastric carcinoma is proposed.

Pathological and computed tomography findings of lymphoepithelioma-like gastric carcinoma with epithelioid granulomas: A case report

Lymphoepithelioma-like carcinoma is a distinct entity among Epstein-Barr virus (EBV)-associated gastric carcinomas, characterized by the presence of a lymphoid stroma with small nests of cancer cells uniformly distributed throughout. Epithelioid granulomas with multinucleated giant cells are extremely rare in the tumor tissue. The presence of epithelioid granulomas with prominent lymphocyte infiltration is associated with a favorable prognosis. This lesion tends to form a bulging mass in the submucosa. In the present study, we report a lymphoepithelioma-like carcinoma of the stomach with epithelioid granulomas which appeared as a bulging mass in CT scanning and correlate it with the pathology. Clinicians and radiologists should recognize the features of such tumors.

Advances in research of Epstein-Barr virus-associated gastric carcinoma

Epstein-Barr virus (EBV), discovered >40 years ago from a Burkitt's lymphoma biopsy, was the first virus to be directly associated with human cancer. It is a ubiquitous human pathogen that usually maintains a harmonious relationship with its host. Rarely, this host-virus balance is perturbed, causing a diverse group of malignancies in both immunocompetent and immunosuppressed patients. The association of EBV with epithelial cell tumors, specifically nasopharyngeal carcinoma and EBV-positive gastric carcinoma, is less clear and is currently considered to be a consequence of the aberrant establishment of virus latency in epithelial cells displaying pre-malignant genetic changes. About 10% of gastric carcinomas harbor clonal EBV. In this paper, we discuss the roles of EBV in gastric carcinogenesis, reviewing mainly epidemiological and clinicopathological studies.

Pathology of epstein-barr virus-associated gastric carcinoma and its relationship to prognosis

Among Epstein-Barr virus (EBV)-associated neoplasms, EBV-associated gastric carcinoma (EBVaGC) is the most common tumor worldwide. In contrast to the predominant site of occurrence of EBV-negative gastric carcinoma in the antrum, EBVaGC occurs most frequently in the proximal stomach, including the cardia, fundus and body. Microscopically, EBVaGC can be subclassified into three histological subtypes according to the host cellular immune responses: lymphoepithelioma-like carcinoma, carcinoma with Crohn's disease-like lymphoid reaction, and conventional-type adenocarcinoma. Recent studies have shown that patients with the lymphoepithelioma-like carcinoma subtype of EBVaGC have the best overall and disease-free survival, followed by Crohn's disease-like reactions, which in turn have better survival than patients with conventional-type adenocarcinoma. Histologic subclassifications of EBVaGCs are based on the differing degree and pattern of infl ammatory response and the extent of desmoplasia. Because these subclassifications appear to be a powerful prognostic parameter, further research into the underlying mechanisms of the cellular immune reaction in these pathologic subtypes of EBVaGCs may play a key role in understanding the innate immune response of patients with this highly aggressive carcinoma.

Epstein-Barr virus-associated lymphoepithelioma-like gastric carcinoma presenting as a submucosal mass: CT findings with pathologic correlation

A lymphoepithelioma-like carcinoma, characterized by a carcinoma with heavy lymphocyte infiltration, is one of the histological patterns observed in patients with Epstein-Barr virus (EBV)-associated gastric carcinoma. Less than half of invasive carcinomas with lymphoepithelioma-like histology can grow to make a submucosal mass. These tumors generally have a better prognosis than conventional adenocarcinomas. We report a case of an EBV-associated lymphoepithelioma-like gastric carcinoma that presented as a submucosal mass on multi-detector (MD) CT and correlate them with the pathology.

CT appearance of Epstein-Barr virus-associated gastric carcinoma

Epstein-Barr virus (EBV) is associated with pathogenesis of several epithelial neoplasms and lymphoproliferative disorders. A certain percentage of gastric carcinomas are associated with EBV. EBV-associated gastric carcinoma is a distinct entity associated with good prognosis. Multiple carcinomas are highly prevalent in EBV-associated gastric carcinomas, and this warrants thorough endoscopic investigation before determining the extent of surgical resection. Therefore, it is important to consider the presence of Epstein-Barr virus in the preoperative CT evaluation of gastric carcinomas. The purpose of this article is to illustrate the CT features of Epstein-Barr virus-associated gastric carcinoma. The surgically resected gastric carcinomas at our institution from 1998 to 2004 were reviewed and were examined for the presence of EBV, and 13 EBV-associated gastric carcinoma lesions were found in 10 patients. The preoperative CT scans were reviewed in these patients. Radiologic features that may suggest the presence of Epstein-Barr virus in gastric carcinoma includes location in the upper part of the stomach, a large thickness-to-width ratio, and a bulky portion projecting from the gastric wall.

Clinicopathological and molecular characteristics of Epstein-Barr virus-associated gastric carcinoma: a meta-analysis

There is conflicting data regarding the clinicopathological significance of the risk factors associated with Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC). To address this controversy, we performed a meta-analysis for the clinicopathological and molecular characteristics of EBVaGC. The relevant published studies were reviewed according to the defined selection criteria. The effect sizes of the outcome parameters were estimated by an odds ratio or a weighted mean difference. This meta-analysis included 48 studies that encompassed a total of 9738 patients. The frequency of EBVaGC was 8.8%, and EBVaGC was significantly associated with ethnicity. It was more predominant in men and in younger individuals. Interestingly, EBVaGC was more prevalent in Caucasian and Hispanic patients than in Asian ones. EBVaGC developed most often in the cardia and body, and it generally showed the diffuse histological type. EBV was highly prevalent in the patients with lymphoepithelial carcinoma. EBVaGC was closely associated with remnant cancer and a CpG island methylator-high status, but not with Helicobacter pylori infection, a TP53 expression, and p53 mutation. In addition, EBVaGC was not significantly associated with the depth of invasion, lymph node metastasis, or the clinical stage. The clinicopathological and molecular characteristics of EBVaGC are quite different from those of conventional gastric adenocarcinoma. However, further study is needed to determine the effect of EBV on the survival of EBVaGC patients.

Spectrum of Epstein-Barr virus-related diseases: a pictorial review

Epstein-Barr virus (EBV) prevails among more than 90% of the adult population worldwide. Most primary infections occur during young childhood and cause no or only nonspecific symptoms; then the virus becomes latent and resides in lymphocytes in the peripheral blood. Inactive latent EBV usually causes no serious consequences, but once it becomes active it can cause a wide spectrum of malignancies: epithelial tumors such as nasopharyngeal and gastric carcinomas; mesenchymal tumors such as follicular dendritic cell tumor/sarcoma; and lymphoid malignancies such as Burkitt lymphoma, lymphomatoid granulomatosis, pyothorax-associated lymphoma, immunodeficiency-associated lymphoproliferative disorders, extranodal natural killer (NK) cell/T-cell lymphoma, and Hodgkin's lymphoma. The purpose of this article is to describe the spectrum of EBV-related diseases and their key imaging findings. EBV-related lymphoproliferative disorders and lymphomas are especially common in immunocompromised patients. Awareness of their clinical settings and imaging spectrum contributes to early detection and early treatment of possibly life-threatening disorders.

Evaluation of epstein-barr virus DNA load in gastric mucosa with chronic atrophic gastritis using a real-time quantitative PCR assay

PURPOSE

It is hypothesized that Epstein-Barr virus (EBV) has already infected the noncarcinomatous gastric mucosa before carcinogenesis of EBV-associated gastric carcinoma. However, the frequency and distribution of EBV infection in the gastric mucosa of chronic atrophic gastritis (CAG) are still unclear. To clarify these points, we evaluated the EBV DNA load in gastric mucosa with CAG.

METHODS

We tested samples from 35 CAG cases. Paired biopsy specimens from five sites of the stomach were obtained according to the Updated Sydney System. One of each pair of specimens was subjected to areal-time quantitative polymerase chain reaction (Q-PCR) assay to detect EBV. Q-PCR was performed using the LightCycler System (Roche, Mannheim, Germany). The other was subjected to hematoxylin and eosin (H&E) and Giemsa staining. The histological degree of CAG was graded according to the Updated Sydney System. To evaluate the surface distribution of gastric mucosal atrophic changes of CAG, we modified the endoscopic classification of Kimura and Takemoto.

RESULT

EBV DNA was detected in 65.7% (23 of 35 cases) of the gastric biopsy specimens of the cases examined. EBV DNA was detected most frequently (92.3%; 12 of 13 cases) in the cases with endoscopically moderate CAG (p < 0.01). There was a significant association between EBV detection and the presence of inflammatory cell infiltration and atrophy in the stomach with endoscopically moderate CAG.

CONCLUSION

EBV mainly infects the gastric mucosa of patients with moderate CAG.

Epstein-Barr virus association is rare in esophageal squamous cell carcinoma

BACKGROUND

A critical role of Epstein-Barr virus (EBV) in carcinogenesis of nasopharyngeal squamous cell carcinoma and gastric adenocarcinoma is strongly suspected. We analyzed the possible EBV association for Japanese squamous cell carcinoma (SCC)-dominant esophageal cancer cases.

METHODS

We retrospectively screened 36 surgically resected esophageal cancer lesions from 36 patients mainly with SCC using in situ hybridization (ISH) for EBV-encoded small RNA1 (EBER-1). EBV DNA analysis using real-time quantitative polymerase chain reaction (Q-PCR) was performed for three recent cases.

RESULTS

We found no EBER-1-positive cancer cell in any tested esophageal cancer lesion. There were many EBER-1-positive tumor-infiltrating lymphocytes in the basaloid SCC lesion and a small number of positive lymphocytes in the other five advanced SCC lesions (14.7% of SCC). One SCC lesion with a highcopy number of EBV DNA had EBER-1-positive lymphocytes.

CONCLUSIONS

EBV is rarely associated with esophageal SCC, and may appear through tumorinfiltrating lymphocytes in some advanced lesions.

Recurrent genomic aberrations in gastric carcinomas associated with Helicobacter pylori and Epstein-Barr virus

Helicobacter pylori and Epstein-Barr virus (EBV) both have been associated with gastric carcinoma. No specific genomic aberrations have been reported in association with these agents. We studied 20 cases of primary gastric carcinoma (including 11 positive for and 6 for EBV) by comparative genomic hybridization with validation of results by fluorescence in situ hybridization, loss of heterozygosity analysis, and immunohistochemistry. The results were analyzed in respect to presence or absence of and EBV. The tumors were also compared in terms of histologic type, tumor location, and lymph node metastases. The most frequently observed aberrations in the gastric carcinomas were gains of chromosome 19, 17, 1p, 11, 20q, and 22. The more common losses were found in 4q, 6q, 13q, and 15q. Gains in chromosome 19 and losses in 9p23-pter were found more commonly in cases with (P < 0.05). Gains in centromeric region of chromosome 19 were more common in the EBV-negative cases (P < 0.05). Immunohistochemical expression of and correlated with gains in the regions containing these genes. Gains in chromosome 11 and losses in 15q15 were more common in cases with EBV (P < 0.01 and P < 0.001, respectively). There was no significant association between any genomic aberration and histologic type, tumor location, or nodal metastases. and EBV are associated with different genomic imbalances, suggesting that these infectious agents exert different influences in the development of gastric carcinoma.

Low prevalence of Epstein-Barr virus in incident gastric adenocarcinomas from the United Kingdom

Epstein-Barr virus has been associated with a proportion of typical gastric adenocarcinomas. Here we report that the prevalence of Epstein-Barr virus in gastric adenocarcinomas from the United Kingdom is one of the lowest in the World. Gastric adenocarcinoma is another tumour whose association with Epstein-Barr virus varies with the population studied.

Relationship between Epstein-Barr virus and lymphoepithelioma-like carcinoma of the lung: a clinicopathologic study of 6 cases and review of the literature

Lymphoepithelioma-like carcinoma (LELC) is a rare form of lung cancer, usually encountered in Chinese patients. Similar to nasopharyngeal carcinoma, LELC of the lung is strongly associated with Epstein-Barr virus (EBV) infection in Asian patients, but there is controversy over whether an association exists in patients from Western countries. To determine whether such a relationship exists, we retrospectively studied 6 cases of primary LELC of the lung, all of which were in Western patients. There were 4 men and 2 women, ranging in age from 49 to 75 years. The tumors ranged from 1 to 4.5 cm in diameter. Four patients had stage I disease, 1 had stage IIb disease, and 1 had stage IIIa disease. All patients are alive without evidence of disease with a follow-up of 18 to 30 months. Formalin-fixed, paraffin-embedded tissue was stained with hematoxylin-eosin for routine evaluation and immunostained for keratin and leukocyte common antigen (LCA). LCA staining was performed to exclude large-cell lymphoma. Immunoperoxidase staining (1:500 clone CS1-4; Dako, Carpinteria, CA) and in situ hybridization were performed to detect EBV. Tumors consisted of solid nests of undifferentiated tumor cells in a syncytial arrangement surrounded by heavy lymphoplasmacytic infiltrate. Tumor cells stained positively for keratin but negative for LCA. All 6 cases were negative for EBV, suggesting no association between EBV and LELC in the Western population.

Epstein-Barr virus-associated gastric carcinoma and atrophic gastritis

Although Epstein-Barr virus (EBV) has been reported to be present in some 7% of gastric carcinomas, the nature of the background gastric mucosa of carcinoma has not been elucidated. The authors evaluated the degree of gastritis in the background gastric mucosa of EBV-associated gastric carcinoma. EBV was detected using in situ hybridization for EBV-encoded small ribonucleic acid 1 (EBER-1) in carcinoma cells. The authors compared gastritis in surgically resected stomachs with 8 EBER-1-positive and 16 EBER-1-negative gastric carcinomas of a similar histologic type using histologic variables of the Updated Sydney System. All eight lesions of EBER-1-positive gastric carcinomas had intestinal metaplasia in the background. Mild to moderate glandular atrophy was common in both groups. Many of the tested lesions, 87.5% of EBER-1-positive and 62.5% of EBER-1-negative lesions, were located near the mucosal atrophic border. The background gastric mucosa for EBV-associated gastric carcinomas is rich in atrophic changes. EBV-associated gastric carcinomas are located near the mucosal atrophic border.

Epstein-Barr virus infection of the colon with inflammatory bowel disease

OBJECTIVE

Epstein-Barr virus (EBV)-infected cells can evoke severe host immune responses, as shown in infectious mononucleosis and EBV-associated gastric carcinoma. To investigate the possible pathological role of EBV in inflammatory bowel disease (IBD), we tested for the presence of EBV in the colon in IBD patients.

METHODS

Surgically resected colonic specimens of 11 patients with Crohn's disease, five patients with ulcerative colitis, nine noninflammatory controls (disease-free area of the colorectal carcinoma), and 10 appendicitis cases were tested using highly sensitive in situ hybridization for EBV-encoded small RNA1 (EBER-1).

RESULTS

EBER-1 was detected in 63.6% of Crohn's disease cases and 60% of ulcerative colitis cases, but not at all in noninflammatory controls and appendicitis cases. EBER-1-positive cells were very rare in the noninflammatory areas of colonic specimens from IBD patients. EBER-1-positive cells were nonepithelial cells (mainly B lymphocytes and a few histiocyte-shaped cells) located in erosive or ulcerative areas of the colonic specimens.

CONCLUSION

The limited presence of EBV-infected cells in the diseased areas of IBD colonic specimens indicated that EBV infection may be related to such diseases.

Case report: hypoechoic submucosal nodules: a sign of Epstein-Barr virus-associated early gastric cancer

The Epstein-Barr virus (EBV) has been reported to be detectable in about 10% of gastric carcinomas. We performed a comparative study of endosonographic findings of EBV-positive and -negative early gastric carcinomas. Epstein-Barr virus was detected in 11.8% (four of 34) of endosonographically observed early gastric carcinoma lesions. Endoscopic ultrasonography (EUS) revealed a hypoechoic mass in the third layer, which reflected submucosal nodules, in 75% (three of four) of EBV-associated lesions. Endoscopically, in 66.7% (two of three) of EBV-associated carcinomas, the depressed lesion was surrounded by a raised margin covered with normal mucosa and was similar to a submucosal tumour (P < 0.05). Histologically, all three cases of EBV-associated lesions with submucosal tumour invasion had submucosal nodules of carcinoma with lymphoid stroma and 75% (three of four) were located in the gastric body. The ratio of maximal thickness to width of EBV-associated lesions was significantly larger than that of EBV-negative lesions, and this tendency was marked in lesions with submucosal tumour invasion (P < 0.05). This study indicated that EUS and endoscopy are of great use for the determination of EBV association with early gastric carcinoma.