Epstein-Barr virus-associated lymphoepithelioma-like gastric carcinoma

Lymphoepithelioma-like gastric adenocarcinoma. Descriptive case series

Lymphoepithelioma-like gastric adenocarcinoma is characterised by a large reactive lymphoplasmacytic infiltrate in the stroma and islets of undifferentiated cells, which express intense and widespread Epstein-Barr virus (EBV). This tumour type has higher survival rates than other gastric cancers, a more proximal location and less lymphatic spread. Our aim is to describe the clinical and pathological characteristics of our series of lymphoepithelioma-like gastric adenocarcinoma. We selected patients who underwent surgery for gastric adenocarcinoma lymphoepithelioma-like variant from 2014 onwards. The results of the following variables were collected: age (years), sex, pre-diagnostic clinical time (months), gastric tumour location, endoscopic biopsy histology, surgical technique, in situ hybridisation for EBER region (Epstein-Barr virus-associated non-coding RNA), microsatellite instability, degree of differentiation, level of resection, tumour size (cm), TNM T value, lymphadenopathy/resected node ratio, overall survival (months) and vital status. Our experience in the lymphoepithelioma-like variant presents as an advanced gastric cancer, possibly related to long-standing prediagnostic symptoms. It behaves as a tumour with expansive local growth with little capacity for lymphatic or metastatic involvement, which could be explained by the prominent intratumoral lymphoid stroma that acts as an antimetastatic barrier.

Prognosis of EBV-positive gastric cancer with lymphoid stroma: systematic review and meta-analysis

BACKGROUND

Although gastric cancer with lymphoid stroma (GCLS) presents better prognosis, uncertainty still exists regarding the association of Epstein-Barr virus (EBV) infection with prognosis of GCLS. Therefore, it is urgent to evaluate the outcome and characteristics of EBV-positive GCLS via a systematic review and meta-analysis.

METHODS

Three medical databases, with a period ranging from 2000 to so far, were searched for observational studies on EBV infection, clinical characteristics and prognosis. Odds ratio (OR) was used to evaluate the mortality and clinical characteristics of EBV-positive GCLS patients. Egger's test and subgroup analysis were conducted to identify the source of heterogeneity.

RESULTS

Nine retrospective studies were finally identified, which involved 618 EBV-positive and 153 EBV-negative GCLS patients. The forest plot indicated that EBV-positive GCLS patients had lower mortality (p = .009; 95% CI: 0.15-0.77; I2 = 48.6%). Both of funnel plot and Egger's tests suggested that there was no publication bias. Nonetheless, subgroup analysis indicated that T1-2 stage ratio more than 50% (p < .001; I2 = 6.7%) and male ratio more than 80% (p < .001; I2 = 0.0%) were valuable for eliminating the heterogeneity. Seven studies including valid information showed that TNM stage of EBV-positive and negative GCLS patients was not statistically different (p = .644; 95% CI: 0.50-1.53; I2 = 0.0%).

CONCLUSIONS

EBV-positive GCLS tends to have lower mortality, suggesting that detection of EBV infection is necessary to predict prognosis of GCLS.

Epstein-Barr Virus-Positive Lymphoepithelioma-Like Carcinoma in Celiac Disease

Lymphoepithelioma-like carcinoma (LELC) is a rare lymphoproliferative malignancy that has been described in many organs over the years. LELC in the duodenum has rarely been described in literature. This article aims to present a rare cause of melena in a young man and the diagnostic challenge that ensued to throw more light on this rare disease. In this article, we describe a 43-year-old man who presented with melena and weight loss and was subsequently diagnosed with LELC after multiple endoscopic biopsies. The patient was also found to have celiac disease in association with his LELC.

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.

Epstein-Barr Virus-associated Mixed Lymphoepithelioma-like Carcinoma and Adenocarcinoma of the Gall Bladder: An Unusual Entity

Schmincke described lymphoepithelioma as an undifferentiated carcinoma with abundant lymphoid stroma in the nasopharynx. Tumors with a similar histomorphology in extrapharyngeal areas have been referred to as lymphoepithelioma-like carcinoma (LELC). The association of an Ebstein-Barr virus (EBV) infection with lymphoepithelioma is well established in the nasopharynx but not so well at the extrapharyngeal sites. Only four cases of LELC have been reported in the gall bladder, of which all were negative for the EBV. This paper reports the first case of an EBV-associated mixed gall bladder carcinoma exhibiting a distinct phenotype of LELC and adenocarcinoma with mucinous differentiation. The EBV was confirmed by the strong granular membranous and cytoplasmic expression of LMP-1 (latent membrane protein-1) on immunohistochemistry and nuclear EBER RNA on chromogen in-situ hybridization in the tumor. This is the first case of LELC positive for EBV in the gall bladder. LELC has a more favorable prognosis than conventional adenocarcinoma or squamous cell carcinoma, irrespective of the site. Although a higher T stage and nodal metastasis were exceptional in the present case in contrast to the previous cases, the EBV-associated lymphocytic response might limit the disease spread and confer better overall survival and prognosis in these patients. Nevertheless, more prospective studies with a larger cohort will be needed to understand the pathogenesis, biological behavior, and prognosis of this rare entity.

Very low risk of lymph node metastasis in Epstein-Barr virus-associated early gastric carcinoma with lymphoid stroma

Background

Epstein-Barr virus-associated early gastric carcinoma with lymphoid stroma (EBV-GCLS) is a rare variant of early gastric carcinomas. Clinicopathological features of this variant remain obscure, especially in Chinese patients. Therefore, we collected EBV-GCLS cases and studied clinicopathology and prognosis.

Methods

By a retrospective review of 595 consecutive radical gastrectomies for early gastric carcinoma from 2006 to 2018, we identified 8 (1.3%, 8/595) EBV-GCLS cases. Clinicopathologic characteristics were compared between EBV-GCLSs and 109 conventional early gastric carcinomas, which were divided into intramucosal, SM1, and SM2 subgroups. The latter 2 subgroups were classified according to the submucosal invasion depth below or over 500 μm.

Results

All 8 EBV-GCLSs occurred in male patients and invaded deep submucosa (SM2) without lymph node metastasis (LNM), four (50%) of which had synchronous non-gastric malignant tumors (3 gastric gastrointestinal stromal tumors and 1 primary clear cell renal cell carcinoma), and four (50%) arose in the proximal stomach. Compared to conventional early gastric carcinomas, EBV-GCLS was significantly more frequent with SM2 invasion, poor differentiation, and synchronous non-gastric carcinoma tumor, but not with age, gender, macroscopic type, location, size, perineural invasion, lymphovascular invasion, and pathologic stage. In invasion-depth stratified comparisons in the SM2 subgroup, the frequency of LNM in EBV-GCLS was significantly lower than that in conventional early gastric carcinomas (p < 0.05) and the 5-year survival rate of patients with EBV-GCLS was better than that with conventional early gastric carcinomas in 3 subgroups (100% vs 91.5, 85.7, 83.9%, respectively), although the differences did not reach a statistically significant level due to the small sample size. Significant differences among 4 subgroups were found in tumor grade, lymphovascular invasion, LNM, pathological stage, and synchronous tumor, but not in age, gender, macroscopic type, tumor size, location, perineural invasion.

Conclusions

Even with poor differentiation and SM2 invasion, EBV-GCLS showed very low risk of LNM and may be a candidate for endoscopic therapy such as endoscopic submucosal dissection.

CT findings and clinical features of Epstein-Barr virus-associated lymphoepithelioma-like gastric carcinoma

Epstein-Barr virus (EBV)-associated lymphoepithelioma-like gastric carcinoma (LELGC) is a rare primary stomach tumor, which has overlapping imaging features with mass forming gastric carcinoma (GC). The aim of our study was to present the computed tomography (CT) findings and clinical features of EBV-associated LELGC to increase awareness of this entity.The CT findings and clinical features of 4 patients with pathologically documented EBV-associated LELGC were retrospectively analyzed.Among the 4 patients, 3 were male, and 1 was female. The medium age was 51 years old. All cases were single lesions including 1 was in the gastric cardia, 1 was in the gastric body, and 2 were in the gastric antrum. A focal thickening of the gastric wall was conducted, with a large thickness-to-length ratio. The low-density stripe of the normal gastric wall abruptly terminated at the edge of the lesion. The CT images of 4 cases showed inhomogeneous density with the radiodensity values ranging from 25 to 48 HU. In addition, an ulcer was demonstrated with an irregular base and slightly raised borders in all cases. Enhancement after injection of contrast material was heterogeneous enhancement (n = 3) or homogeneous (n = 1). After enhancement, obvious enhancement was seen in 1 case, moderate enhancement was seen in 3 cases, with the peak value of the tumor in the portal phase. No evidence of lymph node involvement and distant invasion was observed.Although LELGC is quite rare, it should be considered in differential diagnosis of early GC, advanced GC, and lymphoma. The relatively typical CT appearance, combined the age and sex of patients, can suggest the diagnosis of LELGC.

Gastric Carcinomas With Lymphoid Stroma: An Evaluation of the Histopathologic and Molecular Features

Gastric carcinoma with lymphoid stroma is an uncommon variant enriched for mutually exclusive Epstein-Barr virus (EBV) positivity and mismatch repair (MMR) deficiency. We performed this study to evaluate molecular alterations in this morphologically homogeneous subtype and compare them with 295 conventional gastric cancers analyzed in The Cancer Genome Atlas study. We identified 31 study cases and subjected them to in situ hybridization for EBV-encoded RNAs and assessment for MMR status. Immunostains for PD-L1, β-catenin, and HER2 were performed; extracted DNA was sequenced with a Comprehensive Cancer Panel. Most study patients were older adult men with stage I or II disease (76%). Tumors were classified as EBV/MMR-proficient (MMR-P) (n=7), EBV/MMR deficient (n=12), and EBV/MMR-P (n=12). EBV/MMR-P tumors were usually located in the proximal stomach (83%) and showed heterogenous growth patterns with glandular differentiation (83%). Tumors in all groups showed numerous tumor infiltrating lymphocytes and PD-L1 expression, infrequent nuclear β-catenin accumulation (10%), and lacked both membranous HER2 staining and HER2 amplification. EBV/MMR-deficient tumors showed significantly higher tumor mutation burden (P=0.001) and KRAS alterations (56%) compared with EBV/MMR-P tumors (9%, P=0.05). TP53 variants were more common among EBV/MMR-P tumors (82%) compared with EBV/MMR proficient (0%, P=0.01) and EBV/MMR-deficient (11%, P<0.01) tumors. Alterations in KRAS, ARID1A, PIK3CA, and TP53 followed similar patterns of distribution compared with The Cancer Genome Atlas dataset. We conclude that gastric carcinomas with lymphoid stroma show a spectrum of molecular changes and frequent PD-L1 expression, raising the possibility that this subgroup of tumors may be susceptible to checkpoint inhibitors and/or agents that target receptor tyrosine kinase-mediated signaling.

Gastric Carcinomas With Lymphoid Stroma: Categorization and Comparison With Solid-Type Colonic Carcinomas

OBJECTIVES

To determine whether histologic features could help identify gastric carcinomas with lymphoid stroma associated with microsatellite instability (MSI) (ie, "medullary carcinomas"), Epstein-Barr virus (EBV) infection (termed lymphoepithelioma-like carcinomas in other organ systems), or neither.

METHODS

We identified 17 solid-type gastric carcinomas with lymphoid stroma, assessed EBV and MSI status, and compared features across groups. We also compared them with 51 solid-type colorectal adenocarcinomas.

RESULTS

In the stomach, EBV-associated carcinomas (n = 8) contained intratumoral germinal centers (P = .024) and eosinophils (P = .030) and lacked necrosis (P = .019) compared with MSI-associated carcinomas (n = 5) and non-EBV, non-MSI carcinomas (n = 4). In the colon, MSI-driven carcinomas (n = 40) more frequently contained intratumoral lymphocytes (P = .017) and neutrophils (P = .0050) and less often metastasized to distant sites (P = .0040) than poorly differentiated carcinomas lacking MSI (n = 11).

CONCLUSIONS

Morphology may help classify gastric carcinomas with lymphoid stroma, although ancillary testing appears more reliable. Lymphoepithelioma-like carcinoma and medullary carcinoma should not be used interchangeably.

Lymphoepithelioma-like carcinoma of the upper urinary tract

In this report, we summarized the clinicopathologic features of ten cases of lymphoepithelioma-like carcinoma (LELC) of the upper urinary tract (ureter n = 6; renal pelvis n = 4), a rare variant of urothelial cancer characterized by a malignant epithelial component densely infiltrated by lymphoid cells. The initial diagnosis was made on radical nephrectomy in five cases, nephroureterectomy in three cases, and ureterectomy in two others. Four patients had pathologic stage T1 (n = 2) or T2 (n = 2) tumors, and six patients had stage pT3 disease. Microscopically, all tumors contained pure (n = 3) or predominant (n = 7) LELC, which composed 60 to 80% of the entire tumor. Non-LELC tumor component was adenocarcinoma (n = 2), spindle cell carcinoma (n = 1), or high-grade conventional urothelial carcinoma (n = 4). The LELC component was characterized by indistinct cytoplasmic borders and a syncytial growth pattern. Immunohistochemical staining showed LELC to be positive for cytokeratin AE1/AE3, CK7, CK34ßE12 (rare cells), CK5/6 (rare cells), and CK20 (rare cells); rare cells were p40 positive. GATA 3 was positive in all cases in a variable proportion of cells (20-80%). Lymphoid markers showed a polyclonal proliferation of predominant T cells admixed with B cells. In situ hybridization for the HPV genome was negative in all ten cases. Survival analysis showed no differences between LELC and conventional upper urinary tract urothelial carcinoma, pT classification being the only significant prognostic parameter. Morphologic recognition and distinction from other (non-)neoplastic lesions with prominent lymphoid stroma are critical for its clinical management.

Lymphoepithelioma-like gastric carcinoma: clinicopathological characteristics and infection status

BACKGROUND

Lymphoepithelioma-like gastric carcinoma (LLGC) is a rare subtype of gastric carcinoma (GC) characterized by prominent lymphocytic infiltration. LLGC may be associated with latent Epstein-Barr virus (EBV) infection or microsatellite instability (MSI). This study aims to assess the clinicopathological characteristics, EBV infection, and MSI status in LLGC.

METHODS

A retrospective analysis of GC patients submitted to potentially curative resection between 2009 and 2014 was performed. The LLGC subtype specimens were examined for EBV by in situ hybridization and MSI by immunohistochemical analysis. The LLGC profile was analyzed accordingly to clinicopathological parameters.

RESULTS

From 255 patients, seven were identified on the pathological report as LLGC. Six cases were EBV-positive and one had MSI, showing loss of MLH1 and PMS2 expression. LLGC was more frequently seen in men, and the mean age was 69 years. When compared to non-LLGC, LLGC cases were larger (∼5.8 cm) poorly differentiated tumors and had lower incidence of lymph node metastasis (P = 0.045). Mean number of lymph nodes dissected in the LLGC group was 39.5, and only one patient had a single positive lymph node. In addition, two patients presented associated lesions. LLGC was not associated with HER-2, chromogranin and synaptophysin positivity or Helicobacter pylori infection.

CONCLUSIONS

Distinct pathological aspects and clinical behavior of LLGC reinforce the need for proper recognition of this histological subtype to choose better therapeutic approaches.

Epstein-Barr virus gene expression and latency pattern in gastric carcinomas: a systematic review

METHODS

A systematic review of literature was conducted to identify all published reports regarding the expression of Epstein-Barr Virus (EBV) proteins/transcripts and EBV latency patterns in EBV-associated gastric carcinomas (EBVaGC).

RESULTS

The literature search retrieved 247 papers, of which 25 papers matched the inclusion criteria. The analysis reveals that the most frequently expressed EBV latent proteins are EBNA1 (98.1%) and LMP2A (53.8%), while LMP1 and LMP2B are present in only 10% of cases. Lytic proteins, such as BARF0 and BARF1, and other lytic transcripts are present in almost half of cases.

CONCLUSION

EBVaGC seems to display a unique transcription/latency pattern that does not fit the 'standard' EBV latency patterns and therefore should be further studied to better understand EBVaGC carcinogenesis.

Epstein-Barr virus infection serves as an independent predictor of survival in patients with lymphoepithelioma-like gastric carcinoma

BACKGROUND

The pathogenesis and clinicopathologic characteristics of Epstein-Barr virus (EBV)-negative lymphoepithelioma-like gastric carcinoma (LELC) are still unclear. In addition, it remains controversial whether EBV infection itself affects the prognosis of LELC.

METHODS

Between 1995 and 2011, 145 LELC patients (124 patients with EBV infection and 21 patients without EBV infection) underwent radical gastrectomy with D2 lymph node dissection. The clinicopathologic features and prognosis of EBV-negative LELC cases were compared with those of EBV-positive LELC cases. The median duration of follow-up after surgery was 55 months. Microsatellite instability (MSI) analysis was performed on 20 EBV-negative LELC cases.

RESULTS

EBV-negative LELC accounted for 14.5 % of the total LELC cases. EBV-negative LELC was significantly associated with older age, female sex, advanced T stage, and advanced American Joint Committee on Cancer (AJCC) tumor stage compared with EBV-positive LELC. In univariate analysis, patients with EBV-negative LELC had significantly shorter overall, disease-specific, and recurrence-free survival than those with EBV-positive LELC. The 5-year overall survival rates were 81.0 % for patients with EBV-negative LELC and 96.2 % for patients with EBV-positive LELC. In a Cox proportional hazards model, EBV infection, age, and AJCC tumor stage were identified as independent predictors of overall survival. MSI-high, MSI-low, and microsatellite-stable tumors accounted for 25, 10, and 65 % of EBV-negative LELC cases, respectively. MSI status did not affect the prognosis of EBV-negative LELC cases.

CONCLUSIONS

EBV infection serves as an independent predictor of survival in patients with LELC. EBV-negative LELC exhibited clinicopathologic features and prognosis distinct from those of EBV-positive LELC.

Primary Pulmonary Lymphoepithelioma-like Carcinoma on FDG PET/CT

A 69-year-old male smoker was referred to ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) with the indication of a suspicious solitary pulmonary nodule. FDG PET/CT determined a 2.5 × 2-cm soft-tissue lesion (SUVmax, 16.2) with spiculated margins in the hilum of the right lung. A 1-cm diameter lymphadenopathy on the right hilum with an SUVmax of 3.2 was also determined. Transbronchial biopsy of the right hilar lymphadenopathy did not reveal any malignant features in histopathologic examination, and it was determined to be reactive. The patient underwent a right upper lobe segmentectomy, and the histopathologic evaluation revealed that the tumor was a primary lymphoepithelioma-like carcinoma (LELC) of the lung with negative Epstein-Barr virus (EBV) on in situ hybridization studies. In this case report, we mainly focus on the FDG avidity of this very rare kind of tumor comparatively with previous reports and possible explanations of discordancy in FDG avidity in relation to histopathologic characteristics.

Lymphoepithelioma-like gastric carcinoma in a patient with rectal laterally spreading tumor: A case report

Lymphoepithelioma-like gastric carcinoma (LELGC) is a rare neoplasm of the stomach that accounts for 1-4% of all gastric cancer cases. It is characterized by the presence of a lymphoid stroma with cells arranged primarily in micro alveolar, thin trabecular and primitive tubular patterns or isolated cells. In the present study, the case of a 50-year-old male patient with LELGC and rectal laterally spreading tumor is presented. Following endoscopic submucosal dissection, a diagnosis of carcinoma was reached and the patient underwent total radical gastrectomy. The postoperative pathological stage was IA T1bN0cM0 according to the Tumor-Node-Metastasis classification of gastric carcinoma, and the patient recovered well. The present case is reported to summarize the endoscopic and pathological characteristics of LELGC.

Is gastric lymphoepithelioma-like carcinoma a special subtype of EBV-associated gastric carcinoma? New insight based on clinicopathological features and EBV genome polymorphisms

BACKGROUND

Gastric lymphoepithelioma-like carcinoma (LELC) is a rare entity that is closely associated with Epstein-Barr virus (EBV). However, the EBV latency pattern and genome polymorphisms in gastric LELC have not been systematically explored.

METHODS

The clinicopathological features, EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC in Guangzhou, southern China were investigated and compared with those of ordinary EBV-associated gastric carcinoma (EBVaGC) in the same area.

RESULTS

Ten (1.42%) of 702 gastric carcinoma cases were identified as gastric LELC, in which eight (80%) cases were EBV-positive. The clinicopathological characteristics and EBV latency pattern of EBV-positive gastric LELC were similar to those of ordinary EBVaGC. In EBV genotype analysis, type A strain, type F, I, mut-W1/I, XhoI- and del-LMP1 variants were predominant among EBV-positive gastric LELCs, accounting for eight (100%), six (75%), eight (100%), seven (87.5%), five (62.5%) and six (75%) cases, respectively, which are similar to those in ordinary EBVaGC. For EBNA1 polymorphisms, the V-leu and P-ala subtypes were predominant in EBV-positive gastric LELC, which is different from the predominant V-val subtype in ordinary EBVaGC. EBV-positive gastric LELC has a favorable prognosis when compared to ordinary EBVaGC (median survival time 43.0 vs. 18.0 months).

CONCLUSIONS

Gastric LELC is strongly associated with EBV and EBV-positive gastric LELC should be regarded as a special subtype of EBVaGC. This, to our best knowledge, is the first time in the world that the EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC are systematically revealed.

Lymphoepithelioma-like carcinoma: a distinct type of gastric cancer

BACKGROUND

Lymphoepithelioma-like carcinoma (LELC) is a rare type of gastric carcinoma and has histologic features of intense lymphocytic infiltration. In this study, we attempted to analyze the clinicopathologic characteristics and survival outcome of patients with LELC compared with those with non-lymphoepithelioma-like carcinoma (NLELC).

METHODS

We studied 4282 patients who underwent gastrectomies to treat gastric cancer at the Department of Surgery of the Samsung Medical Center in Seoul, between January 2008 and December 2010. The clinicopathologic features and clinical outcomes of patients with LELC (n = 46) were compared with those with NLELC (n = 4236). In situ hybridization for Epstein-Barr virus (EBV) positivity was performed on the tissue of patients with LELC (n = 46) and NLELC (n = 1247).

RESULTS

The patients with LELC are male predominant and had more upper locations, more indeterminate Lauren classifications, lower T stages, less lymphatic invasion, and more positive EBV in situ hybridization compared with those of the NLELC group (80.4% versus 6.5%). Age, histologic type, Lauren type, the location of the tumor, the depth of the invasion, lymph node metastasis, and venous invasion were independent prognostic factors; however, the LELC type itself was not predictive of outcome. The 5-y survival rate of the LELC group (97.7%) was better than that of the NLELC group (89.4%); however, this difference was not statistically significant (P = 0.127).

CONCLUSIONS

The results of our study suggest that LELC is a less advanced disease than NLELC in terms of depth of invasion and lymphatic invasion at diagnosis. However, our study does not examine LELC as an independent prognostic factor of gastric cancer. Further studies are needed to explore its associations with EBV and a distinct pathway of carcinogenesis from NLELC.

Evidence of Epstein-Barr virus association with gastric cancer and non-atrophic gastritis

Different lines of evidence support an association between Epstein-Barr virus (EBV) and gastric cancer (GC). The main understood risk factor to develop GC is infection by Helicobacter pylori (H. pylori), which triggers a local inflammatory response critical for progression from gastritis to GC. The role of EBV in early inflammatory gastric lesions has been poorly studied. A recent study proposed a cutoff value of 2000 EBV particles to identify patients with increased chances of infection of the gastric epithelium, which may favor the inflammatory process. To better understand the role of EBV in cancer progression, we analyzed 75 samples of GC, 147 control samples of non-tumor gastric tissue derived from GC patients and 75 biopsies from patients with non-atrophic gastritis (NAG). A first-round PCR was used for EBV detection in tumor and non-tumor controls and a more sensitive nested PCR for gastritis samples; both PCRs had lower detection limits above the proposed cutoff value. With this strategy 10.67% of GC, 1.3% of non-tumor controls and 8% of gastritis samples were found positive. An EBER1 in situ hybridization showed EBV infection of epithelial cells in GC and in a third of NAG samples, while in the other NAGs infection was restricted to the mononuclear cell infiltrate. EBV-positive GCs were enriched in lace and cribriform patterns, while these rare patterns were not observed in EBV negative samples. Our results support a role for EBV in GC and early precursor lesions, either as directly oncogenic infecting epithelial cells or indirectly as an inflammatory trigger.

Epstein-Barr Virus Associated Lymphoepithelioma-like Carcinoma at the Lesser Curvature of the Upper Gastric Body: A Case Report

Lymphoepithelioma-like gastric carcinoma (LELGC) is a rare neoplasm of the stomach with dense lymphocytic infiltration. More than 80% of LELGCs are positive for the Epstein-Barr virus (EBV). Here, we report a 64-year old Chinese man with swallowing discomfort while eating food. Endoscopy and computed tomography both showed a submucosal lesion at the lesser curvature of the upper gastric body. The first diagnostic impression was a gastrointestinal stromal tumour. Subsequently, the patient received a wedge resection of the stomach. On histopathological examination, the tumour was found to consist of small nests of neoplastic cells within dense lymphocytic infiltration. Additionally, most of the neoplastic cells were positive for cytokeratin and Epstein-Barr virus-encoded RNA (EBER). Subsequently, the diagnosis of LELGC was made. We believe that physicians should be aware of the diagnosis of submucosal gastric lesions, particularly in older male patients.

Lymphoepithelioma-like hepatocellular carcinoma: a case report and a review of the literature

We report a rare case of lymphoepithelioma-like hepatocellular carcinoma. A 79-year-old Japanese man had undergone curative resection of extrahepatic bile ducts because of bile duct cancer 9 years prior. The bile duct cancer was diagnosed as mucosal adenocarcinoma, and the patient had been followed up every 6 months for the last 9 years. A recent computed tomography examination revealed a tumor, 4.2 cm in size, in the lateral segment of the liver. Based on the imaging findings, the tumor was diagnosed as hepatocellular carcinoma. Serology tests were negative for hepatitis B and C viruses. Chest and abdominal image analyses showed no evidence of metastasis, but a swollen lymph node was noted around the abdominal aorta. The patient subsequently underwent extended lateral segmentectomy and resection of the swollen lymph node. Microscopically, the tumor had the characteristic appearance of poorly differentiated hepatocellular carcinoma. Moreover, an abundant infiltration of inflammatory cells was observed in the tumor. Therefore, we diagnosed the tumor as lymphoepithelioma-like hepatocellular carcinoma. The resected para-aortic lymph node also had a carcinoma with features similar to those of the main tumor. The patient has been alive for 20 months since performance of the surgery. Since the first report of lymphoepithelioma-like hepatocellular carcinoma in 2000, only nine cases have been reported in the medical literature, and the clinicopathological features of the disease have not been well documented. Herein, we describe the clinicopathological features of this case for further understanding of the disease and review past cases in the literature.

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.

Molecular Pathology of Gastrointestinal Cancer

The purpose of this review is to discuss important molecular changes that aid decision making in patient management and play a role in emerging treatment strategies for gastrointestinal malignancies. Although screening and surveillance practices have had an impact on the natural history of some tumor types, gastric carcinoma is a major cause of morbidity and mortality in high prevalence regions and colorectal carcinoma is still the fourth leading cause of cancer related death in the United States.

Lymphoepithelioma-like carcinoma of the breast: a diagnostic and therapeutic challenge

We present a patient with lymphoepithelioma-like carcinoma (LELC) of the breast whose diagnosis is illustrative of the pathology nuances that must be taken into account to successfully reach correct identification of the disease. We also present an overview of our patient's proposed treatment in the context of 16 other reported LELC cases. Although LELC cases are rare, a sufficient number have been reported to discern the natural history of this pathologic entity and to undertake a review of those cases and of the application of oncologic first principles in their management. Given the potential for locoregional spread and distant metastases in LELC, adjuvant therapy has a role in the treatment of this entity.

Coexistence of borderline ovarian epithelial tumor, primary pelvic hydatid cyst, and lymphoepithelioma-like gastric carcinoma

OBJECTIVES

Borderline ovarian tumors (BOTs) represent a heterogeneous group of ovarian epithelial neoplasms. Despite a favorable prognosis, 10-20% of BOTs exhibit progressively worsening clinic. Primary involvement of pelvic organs with echinococcus is very rare. Lymphoepithelioma-like gastric carcinoma is a rare neoplasm of the stomach.

CASE REPORT

A 58-year-old woman referred with abdominal swelling and gastric complaints. Imaging studies revealed a huge cystic mass with multiple septations and solid component, another cystic mass with an appearance of cyst hydatid in the pelvis, and thickening of the small curvature of stomach. Gastroscopy revealed an ulcer with a suspicious malignant appearance, and histology of the endoscopic specimen showed severe chronic inflammation and lymphocytic infiltration. No other involvement of hydatid cyst was detected. In the exploration, there was a 25cm cystic lesion with solid components arising from right ovary, another 6cm cyst over the former, 7cm cystic lesion arising from left ovary, and 10cm mass near the small curvature of the stomach. Excision of the masses; total gastrectomy with esophagojejunal anastomosis; total abdominal hysterectomy; bilateral salpingo-oophorectomy; omentectomy; appendectomy; splenectomy; and pelvic, paraaortic, and coeliac lympadenectomy were performed. Final pathology revealed lymphoepithelioma-like gastric carcinoma, bilateral serous BOT, and hydatid cyst.

DISCUSSION

Hydatid cyst should always be considered in the differential diagnosis of abdominopelvic masses in endemic regions of the world. Preoperative diagnosis of primary pelvic hydatid disease is difficult and awareness of its possibility is very important especially in patients residing in or coming from endemic areas.

Expression of Epstein-Barr Virus Gene and Clonality of Infiltrated T Lymphocytes in Epstein-Barr Virus-associated Gastric Carcinoma

Background

Epstein-Barr virus associated gastric lymphoepithelioma-like carcinoma (LELC) is characterized by the intensive infiltration of lymphoid cells, the presence of EBV, and the better prognosis over typical adenocarcinoma. Thus, it was assumable that viral latent proteins may be responsible for the recruitment of a certain T cell repertoire to EBV-associated gastric carcinoma.

Methods

To examine above possibility, EBV gene expression in gastric carcinoma tissues and usage of TCR among the tumor infiltrating lymphocytes were analyzed.

Results

EBV specific DNA and EBERs RNA were detected in 4 out of 30 patients. RT-PCR analysis revealed that all 4 of EBV-positive tumor tissues expressed EBNA1 mRNA and BARTs and LMP2a was detected only one sample out of 4. However, the EBNA2 and LMP-1 transcripts were not detected in these tissues. CD8⁺ T cells were the predominant population of infiltrating lymphocytes in the EBV-positive gastric carcinoma. According to spectra type analysis of infiltrating T cells, 10 predominant bands were detected by TCR Vβ CDR3 specific RT-PCR from 4 EBV-positive tumor tissues. Sequence analysis of these bands revealed oligoclonal expansion of T cells.

Conclusion

These findings suggest that clonally expanded T cells in vivo might be a population of cytotoxic T cells reactive to EBV-associated gastric 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.

Lymphoepithelioma-like carcinoma of the stomach associated with adenosquamous carcinoma

Lymphoepithelioma-like carcinoma and adenosquamous carcinoma of the stomach are relatively rare tumors. To date, there are no reports on lymphoepithelioma-like carcinoma of the stomach associated with adenosquamous carcinoma. We report herein the first case of such a tumor. A 67-year-old Japanese man presented with dull epigastralgia. The gastric endoscopy revealed an ulcerative cancerous lesion of the upper portion. Histological examination of the gastric tumor showed the coexistence of lymphoepithelioma-like carcinoma and adenosquamous carcinoma. The former showed a positive reaction for Epstein-Barr virus-encoded RNA (EBER). Neoplastic cells of the latter were immunoreactive for p63 and keratin 903, and Alcian blue stain detected acid mucin in glandular lumens. This pattern resembled mucoepidermoid carcinoma in the salivary gland. Finally, this is the first case of gastric lymphoepithelioma-like carcinoma associated with adenosquamous carcinoma, and clinicians and pathologists should recognize the presence of such a tumor.

Lymphoepithelioma-Like Carcinoma of the Stomach with Epithelioid Granulomas

An 83-year-old Japanese man was admitted to our hospital for gastric adenocarcinoma mimicking a submucosal tumor in the gastric body. Considering his general condition, partial resection of the stomach and dissection of regional lymph nodes were performed; a dome-shaped tumor that was largely covered by normal mucosa and having a shallow central stellate ulcer was removed. Histopathologically, the carcinoma cell nests were surrounded by prominent lymphoid stroma. Sarcoid-like epithelioid granulomas were noted both in the tumor stroma and in the regional lymph node with metastasis. Epstein-Barr virus (EBV)-encoded RNA (EBER) in situ hybridization showed an intense and diffuse positive reaction in the carcinoma cells and no reaction in the surrounding gastric and lymphoid tissues. While the presence of lymphoid stroma is a characteristic finding in EBV-associated lymphoepithelioma-like carcinoma, sarcoid-like epithelioid granulomas might be associated with latent EBV infection.

Host inflammatory response predicts survival of patients with Epstein-Barr virus-associated gastric carcinoma

BACKGROUND & AIMS

Lymphoepithelioma-like carcinoma (LELC) is a rare subtype of gastric carcinoma (GC) with a better survival rate than other GCs; most cases of LELC are associated with Epstein-Barr virus (EBV) infection. We investigated whether the survival advantage of LELC is related to the EBV infection itself or to associated inflammatory immune responses.

METHODS

From 1994 to 2008, 123 EBV-associated GCs were identified and compared with 405 EBV-negative GCs. EBV-associated GCs were subclassified, based on the pattern of host inflammatory immune responses, into 3 histologic subtypes: typical LELC (n = 53, 43.1%), Crohn's disease-like lymphocytic reaction (CLR) (n = 52, 42.3%), and conventional adenocarcinoma (n = 18, 14.6%). Patients with curatively resected EBV-negative GC were controls. Univariate and multivariate analyses were used, with Bonferroni correction.

RESULTS

Patients with EBV-associated GC had tumors of proximal location, lower N stage (P < .0001), and lower T stage (P = .02) and were older than controls (P = .0003). Upon univariate analysis, patients with EBV-associated GC had longer survival times than controls (P < .004); this difference was not significant in a multivariate analysis with Cox proportional hazards. Stratification of EBV-associated GCs by host cellular immune responses showed that patients with LELC and LELC+CLR have significantly longer overall survival time (hazard ratio, 0.09 and 0.42, respectively) and disease-free survival (hazard ratio, 0.05 and 0.46, respectively; P < .02).

CONCLUSIONS

Prognosis of EBV-associated GCs depends on the patient's inflammatory response. The definition of LELC should be expanded to include EBV-associated GCs with CLR because these have a prognosis similar to LELC.

Lymphoepithelioma-like carcinoma of the prostate

In this report, we summarized the clinicopathologic features of 5 cases of lymphoepithelioma-like carcinoma of the prostate, a rare variant of prostate cancer characterized by a malignant epithelial component densely infiltrated by lymphoid cells. In all 5 patients, there were obstructive symptoms and elevated prostate-specific antigen; one patient had also hematuria. Their ages ranged from 69 to 82 years (mean age, 76 years). The initial diagnosis of lymphoepithelioma-like carcinoma of the prostate was made on transurethral resection in 3 cases and radical prostatectomy in 2 others. In one case the diagnosis of lymphoepithelioma-like carcinoma admixed with conventional acinar adenocarcinoma was an unexpected finding at time of transurethral resection for benign prostatic hyperplasia. Three patients had clinical stage T3 tumors and another had stage T4 disease; stage T1b was present in the remaining case. Microscopically, all tumors contained lymphoepithelioma-like carcinoma, which comprised 10% to 90% of the entire tumor. All cases were associated with adenocarcinoma, either as the sole pattern in 5 cases or with an additional ductal component in 3 cases. One case had additional features of adenosquamous carcinoma. The lymphoepithelioma-like carcinoma component was characterized by indistinct cytoplasmic borders and a syncytial growth pattern. The stroma was densely infiltrated by lymphoid cells admixed with some plasma cells and neutrophils; one case had a prominent infiltration of eosinophils. Immunohistochemical staining demonstrated that lymphoepithelioma-like carcinoma was positive for prostate-specific antigen, prostate acid phosphatase, alpha-methylacyl coenzyme A racemase, and epithelial membrane antigen; several cytokeratins (AE1/AE3, 7, 8, and 20 [rare cells]) were also immunoreactive. The mean Ki-67 labeling index was 53% (range, 40%-70%), and the p53 expression in all cases was low (10%-20%). The lymphoid component was mainly composed of T with a minor subset of B cells, admixed with some dendritic cells and histiocytes as seen by S100 and CD68 immunoreactivity. Latent membrane protein 1 immunostaining and in situ hybridization for Epstein-Barr virus were negative in all 5 lymphoepithelioma-like carcinoma cases. DNA ploidy of lymphoepithelioma-like carcinoma tumors gave DNA histograms with aneuploid peaks. DNA ploidy of the concurrent adenocarcinoma gave DNA aneuploid peaks except in one DNA diploid case. Four patients died of disease from 8 to 26 months; one patient was lost to follow-up. In summary, lymphoepithelioma-like carcinoma of the prostate arise in aggressive prostate cancers at advanced clinical stage. Morphologic recognition and distinction from other prostatic lesions and tumors with prominent lymphoid stroma is critical for its clinical management.