The genomic landscape of Epstein-Barr virus-associated pulmonary lymphoepithelioma-like carcinoma

Efficacy and safety of immunotherapy in locally advanced or metastatic pulmonary lymphoepithelioma-like carcinoma: a multicenter retrospective study

Background

Pulmonary lymphoepithelioma-like carcinoma (pLELC) is a rare subtype of non-small-cell lung cancer that predominantly affects younger, non-smoking individuals in southern and southeast Asia, where Epstein-Barr virus (EBV) prevalence is high. The efficacy and safety of immunotherapy in pLELC, especially in second-line settings, remain inadequately explored.

Objectives

This study aimed to evaluate the efficacy of immunotherapy, either alone or in combination with chemotherapy, in improving progression-free survival (PFS) and overall survival (OS) in patients with advanced pLELC.

Design

This was a multicenter retrospective study.

Methods

A retrospective analysis was conducted on 252 patients with stage IIIB-IV pLELC treated across six centers. Patients received chemotherapy, immunotherapy, or a combination of both (chemoimmunotherapy). The primary outcomes measured were PFS and OS across different treatment regimens.

Results

Chemoimmunotherapy significantly improved both PFS and OS compared to chemotherapy alone, in both first- and second-line settings. In first-line treatment, chemoimmunotherapy resulted in a median PFS of 17.6 months and OS of 26.1 months, compared to chemotherapy alone (PFS 8.7 months, OS 19.2 months). In the second-line setting, chemoimmunotherapy achieved a median PFS of 5.1 months and OS of 13.5 months, surpassing the outcomes with chemotherapy alone (PFS 3.3 months, OS 8.9 months). High baseline EBV-DNA levels (>2000 copies/mL) and low programmed death ligand 1 (PD-L1) expression (<50%) were associated with poorer outcomes. In addition, patients with high baseline serum tumor markers (STMs) and a dynamic reduction of ⩽20% in STMs exhibited significantly worse PFS and OS.

Conclusion

The study suggests that immunotherapy, particularly when combined with chemotherapy, offers significant survival benefits for patients with advanced pLELC. Baseline EBV-DNA levels, PD-L1 expression, and both baseline and dynamic STM changes serve as important predictors of treatment response, highlighting the need for personalized therapeutic approaches in this unique subtype of lung cancer.

Molecular characterization of EBV-associated primary pulmonary lymphoepithelial carcinoma by multiomics analysis

BACKGROUND

Primary pulmonary lymphoepithelial carcinoma (pLEC) is a subtype of non-small cell lung cancer (NSCLC) characterized by Epstein-Barr virus (EBV) infection. However, the molecular pathogenesis of pLEC remains poorly understood.

METHODS

In this study, we explored pLEC using whole-exome sequencing (WES) and RNA-whole-transcriptome sequencing (RNA-seq) technologies. Datasets of normal lung tissue, other types of NSCLC, and EBV-positive nasopharyngeal carcinoma (EBV+-NPC) were obtained from public databases. Furthermore, we described the gene signatures, viral integration, cell quantification, cell death and immune infiltration of pLEC.

RESULTS

Compared with other types of NSCLC and EBV+-NPC, pLEC patients exhibited a lower somatic mutation burden and extensive copy number deletions, including 1p36.23, 3p21.1, 7q11.23, and 11q23.3. Integration of EBV associated dysregulation of gene expression, with CNV-altered regions coinciding with EBV integration sites. Specifically, ZBTB16 and ERRFI1 were downregulated by CNV loss, and the FOXD family genes were overexpressed with CNV gain. Decreased expression of the FOXD family might be associated with a favorable prognosis in pLEC patients, and these patients exhibited enhanced cytotoxicity.

CONCLUSION

Compared with other types of NSCLC and NPC, pLEC has distinct molecular characteristics. EBV integration, the aberrant expression of genes, as well as the loss of CNVs, may play a crucial role in the pathogenesis of pLEC. However, further research is needed to assess the potential role of the FOXD gene family as a biomarker.

Perioperative immunotherapy plus chemotherapy versus chemotherapy alone for patients with resectable pulmonary lymphoepithelioma-like carcinoma

BACKGROUND

Primary pulmonary lymphoepithelioma-like carcinoma (PLELC) is a rare subtype of non-small-cell lung cancer. This study aims to compare the efficacy and safety of perioperative PD-1/PD-L1 inhibitor plus chemotherapy versus chemotherapy alone in stage II-IIIB PLELC patients.

PATIENTS AND METHODS

This retrospective study included stage II-IIIB PLELC patients. Patients received either perioperative immuno-chemotherapy (IO-Chemo) or chemotherapy alone (Chemo). Data on patient characteristics, treatments, efficacy, toxicities, and pathology were collected. Primary endpoints were major pathological response (MPR) and event-free survival (EFS). Secondary endpoints included objective response rate (ORR), overall survival (OS), and adverse events (AEs).

RESULTS

A total of 72 patients were included in this retrospective study. The ORR was 75.0 % in the IO-Chemo group and 58.3 % in the Chemo group (odds ratio [OR] 0.47 [95 % CI 0.15-1.42]; P = 0.200). The percentage of patients achieving major pathological response (MPR) was 54.2 % in the IO-Chemo group and 12.5 % in the Chemo group (OR 1.91 [95 % CI 1.22-2.99]; P < 0.001). Pathological complete response (pCR) was achieved by 33.3 % of patients in the IO-Chemo group compared to 4.2 % in the Chemo group (OR 1.44 [95 % CI 1.08-1.92]; P = 0.002). The median EFS was not reached in the IO-Chemo group, whereas it was 35.0 months in the Chemo group (95 % CI 14.2-55.8; hazard ratio [HR] 0.42 [95 % CI 0.19-0.93]; P = 0.031). Median overall survival (OS) was not reached after a median follow-up of 47.0 months. Multivariate analysis indicated that the PD-1/PD-L1 inhibitor combination was independently associated with longer EFS (HR = 0.32 [95 % CI 0.11-0.95]; P = 0.043). AEs of any grade occurred in 91.7 % of the patients in the IO-Chemo group versus 89.6 % in the Chemo group.

CONCLUSIONS

In patients with resectable PLELC, perioperative PD-1/PD-L1 inhibitor plus chemotherapy resulted in significantly longer EFS and a higher percentage of patients achieving MPR and pCR than chemotherapy alone, with a tolerable safety profile.

Genomic and clinical characterization of pediatric lymphoepithelioma-like carcinoma

BACKGROUND

Pediatric lymphoepithelioma-like carcinoma (pLELC) is a rare neoplasm with unclear prognosis, genome, and tumor microenvironment. Our study aims to elucidate its genomic and clinical characteristics.

METHODS

Forty-one pLELC patients were enrolled at Sun Yat-sen University Cancer Center from 2012 to 2023. Kaplan-Meier analysis was utilized to estimate progression-free survival (PFS) and overall survival (OS). Baseline plasma protein levels from 16 patients and 9 health controls were analyzed using a Olink proteomic platform and whole exon sequence (WES) was performed on 11 tumor samples from 10 pediatric patients. Immunohistochemistry (IHC) for PD-L1was performed, and the infiltration of CD4+ or CD8+ T cells was evaluated.

RESULTS

Patients receiving anti PD-1 in combination with chemotherapy had a 1-year PFS of 100%, while the 2-year PFS was 72.92% (95%CI: 46.80‒100%). The 1-year OS for patients receiving anti PD-1 in combination with chemotherapy was 100%, and the 2-year OS was 87.5% (95%CI: 67.34-100%). Significant upregulation of immune checkpoint molecules was detected including LAG-3, PD-L1, and galectin-9 in LELC group by proteomic analysis (P < 0.05). The mutational landscape of pediatric LELC presented more genes mutated in pathways associated with immune, DNA repair, cell cycle and NOTCH. Pathway analysis of mutational profiles indicated DNA repair pathway and SWI/SNF complex were potential drug targets for pLELC patients. All the pediatric LELC patients evaluated exhibited positive PD-L1 expression and CD4+/CD8+ T cells infiltration.

CONCLUSIONS

Our findings indicate a promising response rate associated with the combination of PD-1 antibody treatment and chemotherapy in pediatric patients with LELC, providing a theoretical basis for targeting DNA repair pathways. These outcomes suggest that clinical trials involving immune checkpoint inhibitors are warranted in pediatric patients with LELC.

Clinicopathological Features of Epstein-Barr Virus-Positive Neuroendocrine Carcinoma: Analysis of Twenty-Two Cases

Epstein-Barr Virus (EBV)-positive neuroendocrine carcinoma (NEC) is a rare neoplasm with limited histopathological and therapeutic data. This report presents 22 cases of EBV-positive NEC, analyzing age distribution, morphology, and immunophenotype. The median patient age was 47 years (range: 27-67 years), with a male-to-female ratio of 17:5. Most cases (86%, 19/22) were localized to the nasal cavity or nasopharynx, while the remaining three (14%, 3/22) involved the lung, eyelid, and chest wall. Tumors were identified as small cell neuroendocrine carcinoma (SCNEC) or large cell neuroendocrine carcinoma (LCNEC) based on cellular morphology. Immunohistochemical analysis showed positivity for at least one, but generally, two neuroendocrine markers and INI1, while negativity for NUT and squamous cell carcinoma markers, such as p63, p40, and CK5/6. In situ hybridization consistently revealed EBV early RNAs (EBERs) in all cases. Notably, eight patients benefited from chemoradiotherapy. Recognizing this rare tumor is essential for optimizing treatment strategies.

The Treatment of Primary Lymphoepithelioma-Like Carcinoma in the Head and Neck and Nasopharyngeal Carcinoma

BACKGROUND

An uncommon cancer, lymphoepithelioma-like carcinoma (LELC) resembles undifferentiated nasopharyngeal carcinoma (NPC) histologically. The aim is mainly to introduce the diagnosis and treatment of LELC and compare it with NPC in our descriptive study.

METHODS

A total of 278 patients with NPC and 157 patients with head and neck LELC had their medical records examined in this study. The propensity score matching (PSM) approach was employed to attain a 1:1 match between the LELC and NPC groups. Kaplan-Meier analysis was performed for overall survival (OS) of LELC and NPC. To determine their predictive values for OS, univariate and multivariate Cox regression analyses with significant survival differences (p < 0.05) were carried out.

RESULTS

Similar to NPC, 107 (68.2%) LELC cases had Epstein-Barr virus (EBV) infection. LELC of the parotid glands was present in nearly 46.5% of patients with head and neck LELC. Most patients were treated with surgery with neck dissection. After PSM, LELC had similar 5-year OS rates to NPC (81.6% vs. 79.0%). LELC was less prone to distant metastasis compared to NPC. Age, T stage, N stage, and distant metastases were found to be substantially correlated with the outcome of LELC, according to the multivariate Cox regression analysis (p < 0.05).

CONCLUSIONS

EBV infection in the head and neck has been associated with LELC and NPC. When compared to NPC, LELC is more likely to arise in the salivary glands and has a lower incidence of distant metastasis. Surgery with neck dissection is the primary treatment for LELC.

Lymphoepithelial Carcinoma of the Lung: A Case Report and Review of the Literature

Lymphoepithelial or lymphoepithelioma-like carcinoma is a poorly differentiated carcinoma located outside the nasopharynx with similar morphologic characteristics to its nasopharyngeal counterpart. Lymphoepithelial carcinoma of the lung is a rare subtype of squamous cell lung carcinoma frequently associated with Epstein-Barr virus (EBV) infection, accounting for approximately 1% of non-small cell lung carcinomas (NSCLC). We herewith present a case of a 78-year-old female patient who was diagnosed with lymphoepithelial carcinoma of the lung, emphasizing its distinct epidemiological features, clinical workup, and histopathological characteristics. Furthermore, we discuss its histologic differential diagnosis. Finally, we refer to this tumor's unique molecular and immunological profile and its treatment modalities, and we review the literature.

Plasma EBV quantification is associated with the efficacy of immune checkpoint blockade and disease monitoring in patients with primary pulmonary lymphoepithelioma-like carcinoma

Objectives

Primary pulmonary lymphoepithelioma-like carcinoma (PLELC) is a subtype of lung carcinoma associated with the Epstein-Barr virus (EBV). The clinical predictive biomarkers of immune checkpoint blockade (ICB) in PLELC require further investigation.

Methods

We prospectively analysed EBV levels in the blood and immune tumor biomarkers of 31 patients with ICB-treated PLELC. Viral EBNA-1 and BamHI-W DNA fragments in the plasma were quantified in parallel using quantitative polymerase chain reaction.

Results

Progression-free survival (PFS) was significantly longer in EBNA-1 high or BamHI-W high groups. A longer PFS was also observed in patients with both high plasma EBNA-1 or BamHI-W and PD-L1 ≥ 1%. Intriguingly, the tumor mutational burden was inversely correlated with EBNA-1 and BamHI-W. Plasma EBV load was negatively associated with intratumoral CD8+ immune cell infiltration. Dynamic changes in plasma EBV DNA level were in accordance with the changes in tumor volume. An increase in EBV DNA levels during treatment indicated molecular progression that preceded the imaging progression by several months.

Conclusions

Plasma EBV DNA could be a useful and easy-to-use biomarker for predicting the clinical activity of ICB in PLELC and could serve to monitor disease progression earlier than computed tomography imaging.

Metastatic stomach lymphoepithelioma-like carcinoma and immune checkpoint inhibitor therapy: A case report

BACKGROUND

Pulmonary lymphoepithelioma-like carcinoma (PLELC) is a rare type of non-small-cell lung cancer. Stomach lymphoepithelioma-like carcinoma (LELC) metastasis secondary to PLELC has not been reported recently.

CASE SUMMARY

A 64-year-old female was admitted to our hospital for a regular gastroscopy examination with a 6-year history of surgical resection for left PLELC. Positron emission tomography/computed tomography suggested high accumulation of 18F-fludeoxyglucose in the gastric cardia region. Upper gastrointestinal endoscopy confirmed a large mass at the stomach fundus. Immunohistochemistry (IHC) of the biopsy suggested metastatic stomach LELC. Proximal gastrectomy showed that this 6.5 cm × 5.0 cm mass was located in the stomach fundus near the cardia. Histopathological examination showed a poorly differentiated carcinoma with prominent lymphoplasmacytic infiltration. IHC demonstrated that the tumor was positive for CK (AE1/AE3), p63, p40, p53, Ki-67 (70%), and EGFR (3+) and negative for CK7, CK20, Her2, and CD10. In situ hybridization analysis showed positive staining Epstein-Barr virus-encoded RNA. Tumor programmed cell death ligand 1 (PD-L1) expression score was 98%, and the combined positive score was 100, with no evidence of microsatellite instability. Thus, the patient was unequivocally diagnosed with metastatic stomach LELC secondary to pulmonary LELC. After discharge, this patient underwent PD-1 inhibitor treatment (toripalimab, 240 mg) every 3 wk for ten cycles, and she has had no tumor recurrence.

CONCLUSION

For gastric LELC metastasis, PD-1 inhibitor therapy could become a new therapeutic approach, though there is still no evidence from large data sets to support this.

EBV DNA methylation profiles and its application in distinguishing nasopharyngeal carcinoma and nasal NK/T-cell lymphoma

BACKGROUND

As an oncovirus, EBV is associated with multiple cancers, including solid tumors and hematological malignancies. EBV methylation plays an important role in regulating tumor occurrence. However, the EBV methylation profiles in EBV-associated tumor tissues are poorly understood.

RESULTS

In this study, EBV methylation capture sequencing was conducted in several different tumor tissue samples, including NPC, EBVaGC, lung LELC and parotid LELC. Besides, EBV capture sequencing and following qMSP were performed on nasopharyngeal brushing samples from NPC and nasal NKTCL patients. Our results showed that the EBV genome among different types of tumors displayed specific methylation patterns. Among the four types of tumors from epithelial origin (NPC, EBVaGC, lung LELC and parotid LELC), the most significant differences were found between EBVaGC and the others. For example, in EBVaGC, all CpG sites within 1,44,189-1,45,136 bp of the EBV genome sequence on gene RPMS1 were hyper-methylated compared to the others. Differently, significant differences of EBV CpG sites, particularly those located on gene BILF2, were observed between NPC and nasal NKTCL patients in nasopharyngeal brushing samples. Further, the methylated level of BILF2 was further detected using qMSP, and a diagnostic model distinguishing NPC and nasal NKTCL was established. The AUC of the model was 0.9801 (95% CI 0.9524-1.0000), with the sensitivity and specificity of 98.81% (95% CI 93.63-99.94%) and 76.92% (95% CI 49.74-91.82%), respectively.

CONCLUSIONS

Our study reveals more clues for further understanding the pathogenesis of EBV, and provides a possibility for distinguishing EBV-related tumor by detecting specific EBV CpG sites.

Pulmonary squamous cell carcinoma and lymphoepithelial carcinoma - morphology, molecular characteristics and differential diagnosis

Squamous cell carcinoma (SCC) comprises one of the major groups of non-small-cell carcinoma of the lung, and is subtyped into keratinising, non-keratinising and basaloid SCC. SCC can readily be diagnosed using histomorphology alone in keratinising SCC. Confirmatory immunohistochemical analyses should always be applied in non-keratinising and basaloid tumours to exclude differential diagnoses, most prominently adenocarcinoma and high-grade neuroendocrine carcinoma, which may have important therapeutic consequences. According to the World Health Organisation (WHO) classification 2015, the diagnosis of SCC can be rendered in resections of morphologically ambiguous tumours with squamous immunophenotype. In biopsies and cytology preparations in the same setting the current guidelines propose a diagnosis of 'non-small-cell carcinoma, favour SCC' in TTF1-negative and p40-positive tumours to acknowledge a possible sampling bias and restrict extended immunohistochemical evaluation in order to preserve tissue for molecular testing. Most SCC feature a molecular 'tobacco-smoke signature' with enrichment in GG > TT mutations, in line with the strong epidemiological association of SCC with smoking. Targetable mutations are extremely rare but they do occur, in particular in younger and non- or light-smoking patients, warranting molecular investigations. Lymphoepithelial carcinoma (LEC) is a poorly differentiated SCC with a syncytial growth pattern and a usually prominent lymphoplasmacytic infiltrate and frequent Epstein-Barr virus (EBV) association. In this review, we describe the morphological and molecular characteristics of SCC and LEC and discuss the most pertinent differential diagnoses.

Clinical significance of baseline Epstein-Barr virus DNA for recurrent or metastatic primary pulmonary lymphoepithelioma-like carcinoma

Background: This study aimed to evaluate the clinical significance of baseline Epstein-Barr virus (EBV) DNA in recurrent or metastatic primary pulmonary lymphoepithelioma-like carcinoma (PLELC). Methods: 75 patients with baseline EBV DNA were included. The relationships between baseline EBV DNA and clinical characteristics, survival and objective response rate were analyzed. Results: The baseline EBV DNA levels were related to the liver, chest wall, distant lymph node(s) or multiple sites of distant metastasis. The high baseline EBV DNA group (≥41,900 copies/ml) was related to shorter progression-free and overall survival in univariate analysis and remained significant for progression-free survival in multivariate analysis. Conclusion: The baseline EBV DNA is a valuable biomarker for predicting prognosis and reflecting tumor burden in recurrent or metastatic PLELC.

Treatment options for stage III-N2 pulmonary lymphoepithelioma-like carcinoma: A retrospective cohort study

BACKGROUND AND PURPOSE

Pulmonary lymphoepithelioma-like carcinoma (PLELC) is a rare form of non-small cell lung carcinoma (NSCLC) that shares similarities with nasopharyngeal carcinoma. The optimal treatment for stage III-N2 PLELC remains controversial.

METHODS AND MATERIALS

We conducted a retrospective analysis from stage III-N2 PLELC patients between 2009 and 2022 in our center. The patients were categorized into three groups: Group 1 (G1, definitive chemoradiotherapy), Group 2 (G2, radical surgery plus adjuvant chemoradiotherapy), and Group 3 (G3, radical surgery plus adjuvant chemotherapy).

RESULTS

A total of 103 patients were included in the study, with 34, 25, and 44 patients in G1, G2, and G3, respectively. The median follow-up time was 47.4 months. The overall median PFS was 66.6 months, with 3-year PFS and 3-year OS rates of 66.0% and 92.4%, respectively, for all patients. Multivariate analysis revealed no significant difference in PFS between G1 and G2 (p = 0.354), while both groups exhibited significantly longer PFS than G3 (p < 0.001; p = 0.039). Similarly, no significant difference in OS was observed between G1 and G2 (p = 0.649), but both tended to demonstrate improved OS compared to G3 (p = 0.081; p = 0.092). Only one case of grade 3 radiation esophagitis was observed in G1, and no grade 3 or higher radiation pneumonitis were reported.

CONCLUSIONS

Patients with stage III-N2 PLELC have a favorable prognosis, with radiotherapy playing a crucial role in treatment. Both definitive chemoradiotherapy and radical surgery followed by chemoradiotherapy demonstrate favorable efficacy and manageable toxicity.

DNA dioxygenases TET2 deficiency promotes cigarette smoke induced chronic obstructive pulmonary disease by inducing ferroptosis of lung epithelial cell

Chronic obstructive pulmonary disease (COPD) is a significant global cause of morbidity and mortality currently. Long-term exposure of cigarette smoke (CS) inducing persistent inflammation, small airway remodeling and emphysematous lung are the distinguishing features of COPD. Ferroptosis, occurred in lung epithelial cells has recently been reported to be associated with COPD pathogenesis. DNA dioxygenase ten-eleven translocation 2 (TET2) is an important demethylase and its genetic mutation is associated with low forced expiratory volume in 1 s (FEV1) of lung function. However, its role in COPD remains elusive. Here, we found that TET2 regulates CS induced lipid peroxidation through demethylating glutathione peroxidase 4 (GPx4), thus alleviating airway epithelial cell ferroptosis in COPD. TET2 protein levels were mainly reduced in the airway epithelia of COPD patients, mouse models, and CS extract-treated bronchial epithelial cells. The deletion of TET2 triggered ferroptosis and further exaggerated CS-induced airway remodeling, inflammation, and emphysema in vivo. Moreover, we demonstrated that TET2 silencing intensified ferroptosis, while TET2 overexpression inhibited ferroptosis in airway epithelial cell treated with CSE. Mechanically, TET2 protected airway epithelial cells from CS-induced lipid peroxidation and ferroptosis through demethylating the promoter of glutathione peroxidase 4 (GPx4). Finally, co-administration of methylation inhibitor 5'-aza-2'-deoxycytidine (5-AZA) and the antioxidant N-acetyl-cysteine (NAC) have more protective effects on CS-induced COPD than either administration alone. Overall, our study reveals that TET2 is an essential modulator in the lipid peroxidation and ferroptosis of airway epithelial cell, and could act as a potential therapeutic target for CS-induced COPD.

Pathogenesis and therapeutic implications of EBV-associated epithelial cancers

Epstein-Barr virus (EBV), one of the most common human viruses, has been associated with both lymphoid and epithelial cancers. Undifferentiated nasopharyngeal carcinoma (NPC), EBV associated gastric cancer (EBVaGC) and lymphoepithelioma-like carcinoma (LELC) are amongst the few common epithelial cancers that EBV has been associated with. The pathogenesis of EBV-associated NPC has been well described, however, the same cannot be said for primary pulmonary LELC (PPLELC) owing to the rarity of the cancer. In this review, we outline the pathogenesis of EBV-associated NPC and EBVaGCs and their recent advances. By drawing on similarities between NPC and PPLELC, we then also postulated the pathogenesis of PPLELC. A deeper understanding about the pathogenesis of EBV enables us to postulate the pathogenesis of other EBV associated cancers such as PPLELC.

Clinicopathological features and survival of rare primary pulmonary lymphoepithelial carcinoma: A cohort from a single center

BACKGROUND

Primary pulmonary lymphoepithelial carcinoma (PLEC) is a rare subtype of nonsmall cell lung cancer. This study aimed to investigate the clinicopathological and prognostic characteristics of resected primary PLEC.

MATERIALS AND METHODS

In this retrospective study, 95 consecutive patients with primary PLEC, who received radical surgical resection treatment, were examined from October 2009 to January 2022. The clinicopathological features and their association with survival outcomes were analyzed.

RESULTS

Primary PLEC predominated in relatively younger patients and nonsmokers, who lacked driver mutations and were always positive for immunohistochemical markers of the squamous cell lineage. Further, 21.1% of patients had abnormally elevated preoperative serum marker fragments of cytokeratin 19 (Cyfra21-1). The median follow-up time was 43.5 months. The 1-, 3-, and 5-year recurrence-free survival (RFS) rates were 96.5%, 81.8%, and 64.3%, respectively. The median RFS time was not reached. Cox univariate survival analysis showed that patients with positive lymph nodes had significantly worse RFS than those with negative ones (p = 0.017). The patients with open surgery experienced significantly worse RFS than those with video-assisted thoracoscopic surgery (p = 0.038). The multivariate survival analysis confirmed that only lymph node involvement (hazard ratio: 2.769; 95% confidence interval: 1.171-6.548, p = 0.020) was an independent prognostic factor.

CONCLUSIONS

Primary PLEC is a rare type of lung cancer with a favorable outcome, more common in young and nonsmoking Asian populations. Driver gene mutations are rare. Regional lymph node metastasis is an independent prognostic factor for RFS after radical surgical resection.

Comparison of first-line immunotherapy efficacy between advanced lung squamous cell carcinoma and pulmonary lymphoepithelioma-like carcinoma: A propensity score matching multicenter study

Background

Compared with other lung squamous cell carcinomas (LUSC), pulmonary lymphoepithelioma-like carcinoma (pLELC) is closely associated with Epstein-Barr virus (EBV) infections with a unique molecular profile and immune microenvironment. This study was thus established to compare the treatment response and effectiveness of immunotherapy between pLELC and LUSC.

Material and Methods

We enrolled 31 patients with pLELC and 116 with LUSC receiving first-line immunotherapy at three centers in China and compared the treatment response and effectiveness of immunotherapy. Propensity score matching (PSM) was used to balance the differences in baseline data between the two groups.

Results

Before PSM, progression-free survival and overall survival were longer in the pLELC group than in the LUSC group (progression-free survival: hazard ratio (HR), 1.67, 95% CI: 1.05-2.63, P = 0.028; overall survival: HR, 1.90, 95% CI: 1.06-3.40, P = 0.028). This remained unchanged after PSM (progression-free survival: HR, 1.79, 95% CI: 1.02-3.15, P = 0.044; overall survival: HR, 2.20; 95% CI: 1.10-4.37, P = 0.022).

Conclusion

pLELC showed a clinically meaningful survival benefit compared with traditional LUSC following immunotherapy. Subsequent studies should consider the role of the EBV in the tumor immune microenvironment of pLELC.

Targeted therapy for rare lung cancers: Status, challenges, and prospects

Lung cancer causes the most cancer-related deaths worldwide. In recent years, molecular and immunohistochemical techniques have rapidly developed, further inaugurating an era of personalized medicine for lung cancer. The rare subset of lung cancers accounts for approximately 10%, each displaying distinct clinical characteristics. Treatments for rare lung cancers are mainly based on evidence from common counterparts, which may lead to unsolid clinical benefits considering intertumoral heterogeneity. The increasing knowledge of molecular profiling of rare lung cancers has made targeting genetic alterations and immune checkpoints a powerful strategy. Additionally, cellular therapy has emerged as a promising way to target tumor cells. In this review, we first discuss the current status of targeted therapy and preclinical models for rare lung cancers, as well as provide mutational profiles by integrating the results of existing cohorts. Finally, we point out the challenges and future directions for developing targeted agents for rare lung cancer.

Detection of Epstein-Barr virus infection in thymic epithelial tumors by nested PCR and Epstein-Barr-encoded RNA ISH

BACKGROUND

Epstein-Barr virus (EBV) is well known to be associated with a lot of tumors, including lymphoma, nasopharyngeal carcinoma, EBV-associated gastric carcinoma, and some other carcinomas with similar lymphoepithelioma-like features. However, the association between EBV and thymic epithelial tumors (TETs) is inconclusive as reports in this regard are not entirely consistent and the methods employed are of different sensitivity and specificity. The geographical difference of the patients is also one of the reasons for the different points of view.

METHODS

In our study, we examined 72 thymomas, including 3 cases of type A thymomas, 27 cases of type AB, 6 cases of type B1, 26 cases of type B2 and 10 cases of type B3 thymomas, and 15 thymic carcinomas to detect the viral genome at both DNA and RNA levels. The genome DNA of fresh tissues was first screened by nested polymerase chain reaction (PCR), which could be regarded as the most sensitive method to detect small amounts of DNA. Then all the tissue blocks were further submitted for viral localization by Epstein-Barr-encoded RNA (EBER) ISH. Group parameters were assessed using the chi-square test at a significance level of p < 0.05.

RESULTS

Nested PCR results showed that none of type A, eight (29.6%) type AB, one (16.7%) type B1, fifteen (57.7%) type B2, and four (40.0%) type B3 were positive for EBV genome. However, none of them detected EBER expression except for one case of type B2 thymoma. Fourteen (93.3%) thymic carcinomas were positive for EBV by nested PCR, of which three displayed weak nuclear signals within the tumor cells by EBER ISH.

CONCLUSIONS

These results showed that nested PCR was a sensitive method for screening the EBV genome in thymic epithelial tumors. As the malignancy of thymoma increases, the rate of EBV infection became higher. Thymic carcinomas were well associated with the Epstein-Barr virus.There was significant association between the EBV infection rate and thymoma type (p < 0.05). We further analyzed the association between EBV infection and myasthenia gravis. However, it showed no significant difference(p = 0.2754), although the EBV infection rate was higher in the thymomas with myasthenia gravis.

Clinicopathologic features, tumor immune microenvironment and genomic landscape of EBV-related and EBV-unrelated poorly differentiated nonkeratinizing squamous cell carcinoma of the thymus

OBJECTIVES

Knowledge regarding thymic EBV-related poorly differentiated nonkeratinizing squamous cell carcinoma (PDNKSCC), also known as lymphoepithelial carcinoma (LEC), is extremely limited due to its rarity.

MATERIALS AND METHODS

This multi-institutional study enrolled 85 patients with thymic PDNKSCC. DNA in situ hybridization was performed to evaluate the EBV status of all 85 cases. Immunohistochemistry and next generation sequencing were performed to compare the differences in the clinicopathological and molecular features between EBV-related and EBV-unrelated PDNKSCC. Tumor-infiltrating lymphocytes (TILs) were also analyzed by these methods.

RESULTS

The 85 cases were classified into 27 EBV-related PDNKSCCs (31.8 %) and 58 EBV-unrelated PDNKSCCs (68.2 %) according to the EBV status, and 35 Lymphoepithelioma pattern (LP) (41.2 %) and 50 desmoplastic pattern (DP) (58.8 %) according to the histological characteristics. Compared to the EBV-unrelated PDNKSCC, EBV-related PDNKSCC showed a younger patient predominance and more commonly displayed a LP subtype. Additionally, LP-type cases were divided into two groups: Group 1 (EBV-related, 20/85) and Group 2 (EBV-unrelated, 15/85); the DP-type cases were divided into Group 3 (EBV-unrelated, 43/85) and Group 4 (EBV-related, 7/85). The four Groups showed a significant association with patients' OS and PFS. EBV-related PDNKSCC had significantly higher PD-L1 + tumor cells (TCs) and PD-L1 + and CD8 + immune cells (ICs) than EBV-unrelated PDNKSCC. The tumor microenvironment immune type (TMIT) I (PDL1-Tumor+/CD8-High) was more common in EBV-related PDNKSCC, especially in Group 1(LP and EBV related) with more than 90 % cases belonged to TMIT I. Molecular analysis demonstrated that EBV-related PDNKSCC had a significantly higher tumour mutational burden and frequency of somatic mutations than EBV-unrelated cases.

CONCLUSIONS

EBV-related PDNKSCC, especially the Group 1, could be a candidate for immunotherapy and EBV positivity may provide an indication for the selection of targeted therapy due to their high tumour mutational burden.

Neoadjuvant immunotherapy in patients with pulmonary lymphoepithelioma-like carcinoma

OBJECTIVES

Neoadjuvant immunotherapy can be used to treat early-stage non-small-cell lung cancer; however, their effects on pulmonary lymphoepithelioma-like carcinomas (LELC) remain unclear.

MATERIALS AND METHODS

Thirty-nine patients with stages I-III LELC were treated with chemotherapy (Chemo) or neoadjuvant immune-checkpoint inhibitors (ICIs) with or without chemo (IO) before radical-intent surgery. Short-term outcomes included objective response rate (ORR), major pathologic response (MPR), pathologic complete response (PCR), and event-free survival. For comparison, we used IO to treat 63 patients with pulmonary squamous cell carcinomas (SQC) and 47 with adenocarcinomas (ADC). Propensity score matching was analyzed to minimize bias.

RESULTS

ORRs of the LELC-IO and LELC-Chemo groups were 62.5% and 42.9%, respectively (odds ratio, 2.2, 95% confidence interval, 0.423-11.678, p = 0.346). Seven (21.9%) and zero patients in LELC-IO and LELC-Chemo groups, respectively, reached PCR. MPR was identified in five (15.6%) of the 32 patients with LELC-IO. The 1-year progression-free survival rates were 96.9% and 71.4% in IO and Chemo groups, respectively (p > 0.05). However, no difference was observed in ORR, PCR, and MPR between LELC and SQC groups (ORR, 63.2% vs. 68.4%, p > 0.05; PCR, 21.1% vs. 47.4, p > 0.05; MPR, 42.1% vs. 57.9%, p > 0.05) and LELC and ADC groups (ORR, 58.8% vs. 41.2%, p > 0.05; PCR, 17.6% vs. 23.5%, p = 0.672; MPR, 29.4% vs. 47.1%, p > 0.05). The plasma Epstein-Barr virus (EBV) DNA level in a patient was altered posttreatment.

CONCLUSION

Patients with LELC could be benefit from neoadjuvant immunotherapy. Distinct histological subtypes demonstrated comparable efficacy with respect to neoadjuvant immunotherapy.

Anti-angiogenic therapy for advanced primary pulmonary lymphoepithelioma-like carcinoma: a retrospective multicenter study

PURPOSE

Primary pulmonary lympho-epithelioma-like carcinoma (PPLELC) is a rare subtype of primary non-small cell lung cancer (NSCLC). Currently, there is still lack of research data on anti-angiogenic therapy of advanced PPLELC. The purpose of this study was to investigate the efficacy and safety of anti-angiogenic therapy combined with chemotherapy compared with traditional chemotherapy for these patients.

METHODS

Advanced PPLELC patients admitted to six grade A hospitals from January 2013 to January 2021 were selected. The patients received anti-angiogenic therapy combined with chemotherapy (AT group) or chemotherapy (CT group) alone.

RESULTS

A total of 65 patients were included in this study, including 31 patients in the AT group treated with anti-angiogenic therapy combined with chemotherapy and 34 patients in the CT group treated with chemotherapy alone. As of October 1, 2021, the median progression-free survival (PFS) in the AT group was 11.2 months [95% confidence interval (CI), 5.9-16.5]. The median PFS in the CT group was 7.0 months [95%CI, 5.1-8.9] [Hazard Ratio (HR), 0.49; 95%CI, 0.29-0.83; P = 0.008]. The 1-year PFS rates were 41.9% and 17.6%, respectively. The overall response rates (ORR) of two groups were 45.2% (95% CI, 0.27-0.64), 38.2% (95% CI, 0.21-0.56), (P = 0.571). The disease control rates (DCR) of two groups were 93.5% (95% CI, 0.84-1.03), 88.2% (95% CI, 0.77-1.00), (P = 0.756).

CONCLUSION

Among patients with advanced PPLELC, the PFS of patients with anti-angiogenic therapy combined with chemotherapy is better than that of patients with chemotherapy alone. Anti-angiogenic therapy combined with chemotherapy is an optional treatment scheme.

Efficacy and safety of gemcitabine and capecitabine combination for patients with previously treated advanced primary pulmonary lymphoepithelioma-like carcinoma: a retrospective single-arm cohort study

Background

Primary pulmonary lymphoepithelioma-like carcinoma (PLELC) is a rare and unique subtype of non-small cell lung cancer (NSCLC). Studies reporting on salvage treatment for pretreated PLELC are limited. Positive interactions between gemcitabine (GEM) and capecitabine (CAP) have been demonstrated in preclinical studies. In addition, the clinical benefit of the combination has been reported for other malignancies. However, the efficacy and safety of the combination for pretreated PLELC remain unclear. Therefore, we conducted this retrospective study to examine the activity and safety of gemcitabine plus capecitabine (GEM/CAP) combination for previously treated PLELC.

Methods

Patients with PLELC at Sun Yat-sen University Cancer Center who received GEM combined with CAP between May 2013 and January 2021 as the second-line therapy or beyond were retrospectively enrolled. Treatment consisted of intravenous GEM (1,000 mg/m² on days 1 and 8) and oral CAP (1,000 mg/m² twice daily on days 1-14) every 3 weeks. Evaluation of response was performed every 2 cycles in accordance with Response Evaluation Criteria in Solid Tumors version 1.1. Safety was assessed in accordance with Common Terminology Criteria for Adverse Events version 5.0. Clinical characteristics were collected from medical records. The survival data were obtained by medical records or telephone. Follow-ups were performed until February 3^rd, 2021.

Results

A total of 16 patients were enrolled in this study. There were 5, 4, 4, and 3 patients treated with GEM/CAP combination as the second-, third-, fourth-, and fifth-line settings, respectively. There were 8 patients with partial response (PR) (50.00%), 6 with stable disease (SD) (37.50%), 2 with progressive disease (PD) (12.50%), and none with complete response (CR). The objective response rate and disease control rate (DCR) were 50.00% and 87.50%, respectively. The most common hematological and nonhematological adverse events (AEs) at any grade were neutropenia (31.25%) and hand-foot syndrome (43.75%). At a median follow-up of 29.3 months with 95% confidence interval (CI) of 20.3 to 38.3 months, the median progression-free survival (PFS) was 9.3 months (95% CI: 6.5-12.1 months). The median overall survival (OS) was 41.5 months (95% CI: 3.1-79.8 months).

Conclusions

This retrospective study demonstrated the potential clinical benefit of GEM in combination with CAP for pretreated PLELC. Future multicenter large-scale, prospective studies are warranted.

Prognostic significance of circulating Epstein-Barr virus DNA in pulmonary lymphoepithelioma-like carcinoma: A meta-analysis and validation study

In small-scale studies, circulating Epstein-Barr virus (EBV) DNA levels have prognostic value in patients with pulmonary lymphoepithelioma-like carcinoma (LELC). Therefore, we performed a comprehensive meta-analysis to evaluate the prognostic significance of circulating EBV DNA levels in patients with pulmonary LELC. Studies that discussed the prognostic significance of circulating EBV DNA detection in pulmonary LELC were eligible for inclusion in this study. The overall survival (OS) and progression-free survival (PFS) were the primary outcomes. Pooled hazard ratio (HR), 95% confidence intervals (CIs), and p value were calculated to estimate the prognostic significance of EBV DNA levels. Additionally, we conducted a further observation using an independent cohort. The pooled HR and 95% CI of pretreatment EBV DNA levels for OS and PFS were 3.63 (95% CI: 2.90-4.55) and 2.88 (95% CI: 1.90-4.38), respectively. The pooled HR and 95% CI for Posttreatment EBV DNA levels for OS and PFS were 3.77 (95% CI: 2.96-4.80) and 3.52 (95% CI: 1.91-6.51, p < 0.001), respectively. The independent cohort showed similar results that patients with high pretreatment EBV DNA or positive posttreatment EBV DNA had significantly inferior PFS. Circulating EBV DNA levels provide prognostic values of survival and treatment response in pulmonary LELC patients.

Anti-PD-1 antibodies, a novel treatment option for advanced chemoresistant pulmonary lymphoepithelioma carcinoma

Background

Pulmonary lymphoepithelioma-like carcinoma (LELC) exhibits a unique immune microenvironment, including high PD-L1 expression and abundant infiltrating-immune cells. However, the availability of PD-1/PD-L1 inhibitors in patients with LELC is still not determined.

Methods

A total of 36 cases of pulmonary LELC treated with PD-1/PD-L1 inhibitors were reviewed, including 10 cases from our institute and 26 cases included from the literature. The Kaplan-Meier method and log-rank test were utilized to analyze the survival outcomes of LELC patients receiving immunotherapy, and the factors related to immunotherapy response were further examined.

Results

Of the 10 patients from our institute, the median age was 53.5 years, adrenal glands and distant lymph nodes were the most common metastatic sites, and 4 of 8 (50%) patients had a PD-L1 TPS ≥50%. The median progression-free survival and overall survival in patients from our institute and from the literature were 11.6 and 27.3 months, 17.2 months and not reached, respectively. In all 36 patients, the objective response rate was as high as 57.6%. Patients with higher PD-L1 expression were more likely to have a tumor response, but the association of PD-L1 expression with survival time remains to be determined.

Conclusions

PD-1/PD-L1 inhibitors in patients with pulmonary LELC demonstrated a promising efficacy in retrospective cohorts, and deserve further validation in prospective studies administrating in front-line setting.

Synchronous Diagnosis of Squamous Cell Carcinoma of the Lung and Mixed Cellularity Hodgkin Lymphoma of the Nasopharynx

Hodgkin lymphoma (HL) is a highly curable B cell lymphoproliferative neoplasm with a bimodal age distribution. Lung cancer is the leading cause of cancer-related deaths in both sexes. We present a rare case of synchronous squamous cell carcinoma (SCC) of the lung and mixed cellularity HL of the nasopharynx. A gentleman in his 70s presented with right-sided chest pain and shortness of breath. CT of the chest showed a peripheral lung mass, and a biopsy confirmed SCC of the lung. The patient underwent a positron emission tomography/computed tomography (PET/CT) for staging that revealed an ¹⁸F-fluorodeoxyglucose (FDG)-avid mass in the nasopharynx. Flexible nasal endoscopy and biopsy of the nasopharyngeal mass revealed mixed cellularity classical HL. The patient was started on chemoimmunotherapy for lung cancer. Unfortunately, two months after initiation of treatment, the patient died from COVID-19 pneumonia and multiorgan failure.

Immune checkpoint inhibitors in lung tumors with rare histologies and other thoracic malignancies

In recent years, immunotherapy has significantly changed the treatment of locally advanced/metastatic non-small-cell lung cancer (NSCLC). Conversely, the role of immunotherapy in NSCLC with uncommon histologies remains unclear, while in other rare thoracic malignancies, such as malignant pleural mesothelioma and thymic epithelial tumors, the use of immune checkpoint inhibitors is modifying therapeutic strategies with solid hopes for the future. However, larger prospective studies are urgently needed to define the best treatment strategies and the role of immunotherapy in these orphan tumors. This review provides a comprehensive overview of the emerging role of immunotherapy in the treatment of patients affected by these rare thoracic malignancies.

Favorable response of primary pulmonary lymphoepithelioma-like carcinoma to sintilimab combined with chemotherapy: A case report

BACKGROUND

There is no established treatment for primary pulmonary lymphoepithelioma-like carcinoma (LELC) until now.

CASE SUMMARY

In this study, the patient responded well to sintilimab combined with paclitaxel and carboplatin, showing no obvious side effects. Meantime, the values of carbohydrate antigen 15-3 (CA15-3) and carbohydrate antigen 72-4 (CA72-4) gradually returned to normal.

CONCLUSION

Immunotherapy combined with chemotherapy in advanced-stage LELC may be more effective than immunotherapy or chemotherapy alone. CA15-3 and CA72-4 are biomarkers for evaluating therapeutic effects for LELC.

PD-1/PD-L1 combined with LAG3 is associated with clinical activity of immune checkpoint inhibitors in metastatic primary pulmonary lymphoepithelioma-like carcinoma

Primary pulmonary lymphoepithelioma-like carcinoma (PLELC) is an Epstein–Barr virus (EBV)-related, rare subtype of non-small-cell lung cancer (NSCLC). Immune checkpoint inhibitors (ICI) show durable responses in advanced NSCLC. However, their effects and predictive biomarkers in PLELC remain poorly understood. We retrospectively analyzed the data of 48 metastatic PLELC patients treated with ICI. Pretreated paraffin-embedded specimens (n = 19) were stained for PD-1, PD-L1, LAG3, TIM3, CD3, CD4, CD8, CD68, FOXP3, and cytokeratin (CK) by multiple immunohistochemistry (mIHC). Next-generation sequencing was performed for 33 PLELC samples. Among patients treated with ICI monotherapy (n = 30), the objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), and overall survival (mOS) were 13.3%, 80.0%, 7.7 months, and 24.9 months, respectively. Patients with PD-L1 ≥1% showed a longer PFS (8.4 vs. 2.1 months, p = 0.015) relative to those with PD-L1 &lt;1%. Among patients treated with ICI combination therapy (n = 18), ORR, DCR, mPFS, and mOS were 27.8%, 100.0%, 10.1 months, and 19.7 months, respectively. Patients with PD-L1 ≥1% showed a significantly superior OS than those with PD-L1 &lt;1% (NA versus 11.7 months, p = 0.001). Among the 19 mIHC patients, those with high PD-1/PD-L1 and LAG3 expression showed a longer PFS (19.0 vs. 3.9 months, p = 0.003). ICI also showed promising efficacy for treating metastatic PLELC. PD-L1 may be both predictive of ICI treatment efficacy and prognostic for survival in PLELC. PD-1/PD-L1 combined with LAG3 may serve as a predictor of ICI treatment effectiveness in PLELC. Larger and prospective trials are warranted to validate both ICI activity and predictive biomarkers in PLELC.

This study was partly presented as a poster at the IASLC 20th World Conference on Lung Cancer 2019, 7–10 September 2019, Barcelona, Spain.

PD-1 inhibition plus platinum-based chemotherapy (PBC) or PBC alone in the first-line treatment of locally advanced or metastatic pulmonary lymphoepithelioma-like carcinoma

Background

Pulmonary lymphoepithelioma-like carcinoma (PLELC) is a distinctive subtype of non-small cell lung carcinoma that was not well presented in clinical studies. The management of advanced PLELC remains an important, unmet need due to the paucity of high-grade evidence. Herein, we carried out a multicenter, retrospective study to assess the effectiveness and tolerability of PD-1/PD-L1 inhibitor plus chemotherapy versus chemotherapy alone for patients with advanced PLELC in the first-line setting.

Patients and Methods

This retrospective study enrolled patients with advanced PLELC receiving first-line treatment with PD-1 inhibition plus chemotherapy (IO-Chemo group) or chemotherapy alone (Chemo group) in three medical centers in China. The survival outcomes, efficacy, and safety profile were investigated. The primary endpoint was progression-free survival (PFS). Secondary endpoints included objective response rate (ORR), overall survival (OS), and adverse events (AEs).

Results

A total of 133 patients were enrolled. PFS was significantly longer in the IO-Chemo group (median 12.8 months [95% CI 5.2-20.4]) than that in the Chemo group (median 7.7 months [95% CI 6.8-8.6]; hazard ratio [HR] 0.48 [95% CI 0.31-0.74]; P=0.001). ORR was 74.5% (95% CI, 63.0-86.1) in the IO-Chemo group and 34.6% (95% CI, 24.1-45.2) in the Chemo group (P&lt;0.001). The median OS was not reached in the IO-Chemo group versus 35.7 months (95% CI 26.7-44.8) in the Chemo group (HR 0.47 [95% CI 0.20-1.07]; P=0.065). Multivariate analysis revealed that PD-1/PD-L1 inhibitor combination was independently associated with longer PFS (HR 0.40 [95% CI 0.25-0.63]; P&lt;0.001). Grade 3 or higher AEs occurred in 36 (65.5%) patients in the IO-Chemo group and 56 (71.8%) patients in the Chemo group, respectively.

Conclusions

In patients with advanced PLELC, adding PD-1/PD-L1 inhibitor to platinum-based chemotherapy significantly increased PFS and ORR with a tolerable safety profile.

Clinical features and treatment outcome of lymphoepithelioma-like carcinoma from multiple primary sites: a population-based, multicentre, real-world study

BACKGROUND

Lymphoepithelioma-like carcinoma (LELC) is a rare and unique subtype of cancer that histologically resembles undifferentiated nasopharyngeal carcinoma (NPC). The population-based analysis of LELC and the optimal treatment remains unclear.

MATERIALS AND METHODS

This real-world, retrospective study investigated 770 patients with LELC for primary site, treatment, and survival outcomes from 2005 to 2019 from five cancer centres in China. The overall survival (OS) of different subgroups was appraised by log-rank tests and Kaplan-Meier analysis.

RESULTS

Primary sites LELC included the lung (597 cases, 77.5%), salivary gland (115 cases, 14.9%), and others. The median progression-free survival (PFS) of LELC patients was 47.4 months. The median overall survival (OS) was not reached. The 5-year survival rate for LELC patients was 77.8%. Most patients in stages I and II received surgery. The majority of patients in stage III received surgery and radiotherapy. More than half of the patients in stage IV received chemotherapy. Among relapsed or metastatic cases receiving chemotherapy, patients who received immunotherapy at any time presented with a superior OS than those without immunotherapy (P < 0.0001, HR = 0.39, 95% CI 0.25-0.63). Compared with the SEER database, patients with LELC had a better prognosis than NPC, with a 5-year overall survival of 77.3% vs. 56.8% (P < 0.001).

CONCLUSION

Our data provide treatment patterns and outcomes for LELC from various primary sites. Randomized controlled studies are necessary to further define the standard of care for patients with LELC. Trial registration This clinical trial was registered at ClinicalTrials.gov (No. NCT04614818).

Virus-Mediated Inhibition of Apoptosis in the Context of EBV-Associated Diseases: Molecular Mechanisms and Therapeutic Perspectives

Epstein-Barr virus (EBV), the representative of the Herpesviridae family, is a pathogen extensively distributed in the human population. One of its most characteristic features is the capability to establish latent infection in the host. The infected cells serve as a sanctuary for the dormant virus, and therefore their desensitization to apoptotic stimuli is part of the viral strategy for long-term survival. For this reason, EBV encodes a set of anti-apoptotic products. They may increase the viability of infected cells and enhance their resistance to chemotherapy, thereby contributing to the development of EBV-associated diseases, including Burkitt’s lymphoma (BL), Hodgkin’s lymphoma (HL), gastric cancer (GC), nasopharyngeal carcinoma (NPC) and several other malignancies. In this paper, we have described the molecular mechanism of anti-apoptotic actions of a set of EBV proteins. Moreover, we have reviewed the pro-survival role of non-coding viral transcripts: EBV-encoded small RNAs (EBERs) and microRNAs (miRNAs), in EBV-carrying malignant cells. The influence of EBV on the expression, activity and/or intracellular distribution of B-cell lymphoma 2 (Bcl-2) protein family members, has been presented. Finally, we have also discussed therapeutic perspectives of targeting viral anti-apoptotic products or their molecular partners.

Tumor infiltrating lymphocytes-based subtypes and genomic characteristics of EBV- associated lymphoepithelioma-like carcinoma

Tumor infiltrating lymphocytes (TILs) offer a key for morphological diagnosis of lymphoepithelioma-like carcinoma (LELC) and are the foundation of onco-immunology. To date, no reports have found a specific risk stratification value of TILs and related it to genomic variation in LELC. Based on the stromal TILs (str-TILs) ratio, we classified 105 EBV-associated LELC cases into two subtypes: patients with ≥ 60% str-TILs area ratio in tumor were classified as subtype I, and otherwise as subtype II. Subtype I patients had significantly better progression-free survival (PFS) and overall survival (OS). We also explored genomic characteristics of EBV-associated LELC within different involved organs. We performed whole-exome sequencing for 51 patients with enough tissue and analyzed genomic characteristics of EBV-associated LELC. Overall, EBV-associated LELCs were characterized by low somatic mutation rate and copy number variations; the enriched genetic lesions affected RTK-RAS, PI3K and cell cycle pathways. Moreover, EBV-associated LELCs from different organs were more similar to each other genetically as compared with other traditional carcinomas of the same sites -as evidenced by unsupervised clustering based on the quantitative data from both mutation signature and chromosomal aneuploidies. Notably, EBV-associated LELC patients with oncogenic driver alterations showed a worse prognosis compared with patients without such alterations. This article is protected by copyright. All rights reserved.

Efficacy and predictive biomarkers of immunotherapy in Epstein-Barr virus-associated gastric cancer

Background

Epstein-Barr virus (EBV)-associated gastric cancer (GC) (EBVaGC) is a distinct molecular subtype of GC with a favorable prognosis. However, the exact effects and potential mechanisms of EBV infection on immune checkpoint blockade (ICB) efficacy in GC remain to be clarified. Additionally, EBV-encoded RNA (EBER) in situ hybridization (ISH), the traditional method to detect EBV, could cause false-positive/false-negative results and not allow for characterizing other molecular biomarkers recommended by standard treatment guidelines for GC. Herein, we sought to investigate the efficacy and potential biomarkers of ICB in EBVaGC identified by next-generation sequencing (NGS).

Design

An NGS-based algorithm for detecting EBV was established and validated using two independent GC cohorts (124 in the training cohort and 76 in the validation cohort). The value of EBV infection for predicting ICB efficacy was evaluated among 95 patients with advanced or metastatic GC receiving ICB. The molecular predictive biomarkers for ICB efficacy were identified to improve the prediction accuracy of ICB efficacy in 22 patients with EBVaGC.

Results

Compared with orthogonal assay (EBER-ISH) results, the NGS-based algorithm achieved high performance with a sensitivity of 95.7% (22/23) and a specificity of 100% (53/53). EBV status was identified as an independent predictive factor for overall survival and progression-free survival in patients with DNA mismatch repair proficient (pMMR) GC following ICB. Moreover, the patients with EBV+/pMMR and EBV−/MMR deficient (dMMR) had comparable and favorable survival following ICB. Twenty-two patients with EBV+/pMMR achieved an objective response rate of 54.5% (12/22) on immunotherapy. Patients with EBVaGC with a high cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) level were less responsive to anti-programmed death-1/ligand 1 (PD-1/L1) monotherapy, and the combination of anti-CTLA-4 plus anti-PD-1/L1 checkpoint blockade benefited patients with EBVaGC more than anti-PD-1/L1 monotherapy with a trend close to significance (p=0.074). There were nearly significant differences in tumor mutational burden (TMB) level and SMARCA4 mutation frequency between the ICB response and non-response group.

Conclusions

We developed an efficient NGS-based EBV detection strategy, and this strategy-identified EBV infection was as effective as dMMR in predicting ICB efficacy in GC. Additionally, we identified CTLA-4, TMB, and SMARCA4 mutation as potential predictive biomarkers of ICB efficacy in EBVaGC, which might better inform ICB treatment for EBVaGC.

Comparison of Immunotherapy, Chemotherapy, and Chemoimmunotherapy in Advanced Pulmonary Lymphoepithelioma-Like Carcinoma： A Retrospective Study

Pulmonary lymphoepithelioma-like carcinoma (pLELC) is a rare subtype of lung cancer that is associated with the Epstein-Barr virus in Asia. Due to the lack of prospective studies, the best first-line treatment and survival outcomes remain unclear. Herein, This study investigated the efficacy and safety of different treatment regimens for advanced pLELC. This retrospective study included 68 patients with advanced pLELC from two centers in China. Patients were divided into three groups according to different first-line treatments: chemotherapy (n=49, 72.1%), immunotherapy (n=7, 10.3%), and chemoimmunotherapy (n=12,17.6%). The primary endpoint of this study was the 2-year progression-free survival (PFS) of each group. The results show that the median PFS was 6.9 months (range, 2.3–not estimable) in the chemotherapy group, 11.0 months (range, 2–not estimable) in the immunotherapy group, and 11.8 months (range, 6–not estimable) in the chemoimmunotherapy group. There was a significant difference in 2-year PFS between the chemoimmunotherapy group and the chemotherapy group (hazard ratio, 0.38, 95% confidence interval: 0.18-0.78, log-rank P=0.007). The most frequent grade 3-4 adverse event in the chemotherapy and chemoimmunotherapy groups was myelosuppression (10/49 [22.4%] and 4/12 [33.3%], respectively). The most frequent grade 3-4 adverse events in the immunotherapy group were diarrhea (1/7, 14.8%) and hepatotoxicity (1/7, 14.8%). Chemoimmunotherapy had the highest 2-year PFS as a first-line treatment for advanced pLELC compared to chemotherapy and immunotherapy. This study suggests that chemoimmunotherapy may be the best first-line treatment for patients with advanced pLELC.

Epstein-Barr Virus Infection in Lung Cancer: Insights and Perspectives

Lung cancer (LC) is the leading cause of cancer death worldwide. Tobacco smoke is the most frequent risk factor etiologically associated with LC, although exposures to other environmental factors such as arsenic, radon or asbestos are also involved. Additionally, the involvement of some viral infections such as high-risk human papillomaviruses (HR-HPVs), Merkel cell polyomavirus (MCPyV), Jaagsiekte Sheep Retrovirus (JSRV), John Cunningham Virus (JCV), and Epstein-Barr virus (EBV) has been suggested in LC, though an etiological relationship has not yet been established. EBV is a ubiquitous gamma herpesvirus causing persistent infections and some lymphoid and epithelial tumors. Since EBV is heterogeneously detected in LCs from different parts of the world, in this review we address the epidemiological and experimental evidence of a potential role of EBV. Considering this evidence, we propose mechanisms potentially involved in EBV-associated lung carcinogenesis. Additional studies are warranted to dissect the role of EBV in this very frequent malignancy.

Genome-Wide Profiling of Epstein-Barr Virus (EBV) Isolated from EBV-Related Malignancies

Epstein–Barr virus (EBV) is the cause of certain cancers, such as Burkitt lymphoma, Hodgkin lymphoma, NK/T cell lymphoma, nasopharyngeal carcinoma, and a subset of gastric carcinomas. The genome-wide characteristics of EBV are essential to understand the diversity of strains isolated from EBV-related malignancies, provide the first opportunity to test the general validity of the EBV genetic map and explore recombination, geographic variation, and the major features of variation in this virus. Moreover, understanding more about EBV sequence variations isolated from EBV-related malignancies might give important implications for the development of effective prophylactic and therapeutic vaccine approaches targeting the personalized or geographic-specific EBV antigens in these aggressive diseases. In this chapter, we will mainly focus on the EBV genome-wide profiling in three common EBV-related cancers in Asia, including nasopharyngeal carcinoma, EBV-associated gastric carcinoma, and NK/T-cell lymphoma.

Genomic Landscapes of Epstein-Barr Virus in Pulmonary Lymphoepithelioma-like Carcinoma

Epstein-Barr virus (EBV) infection is associated with multiple malignancies, including pulmonary lymphoepithelioma-like carcinoma (pLELC), a particular subtype of primary lung cancer. However, the genomic characteristics of EBV related to pLELC remain unclear. Here, we obtained the whole-genome dataset of EBV isolated from 78 pLELC patients and 37 healthy controls using EBV-captured sequencing. Compared to the reference genome (NC_007605), a total of 3995 variations were detected across pLELC-derived EBV sequences, with the mutational hotspots located in latent genes. Combined with 180 published EBV sequences derived from healthy people in Southern China, we performed a genome-wide association study and identified 32 variations significantly related to pLELC (p < 2.56×10^-05, Bonferroni correction), with the top signal of SNP coordinate T7327C (OR = 1.22, p = 2.39×10^-15) locating in the origin of plasmid replication (OriP). The results of population structure analysis of EBV isolates in East Asian showed the EBV strains derived from pLELC were more similar to those from nasopharyngeal carcinoma (NPC) than other EBV-associated diseases. In addition, typical latency type-II infection were recognized for EBV of pLELC at both transcription and methylation levels. Taken together, we defined the global view of EBV genomic profiles in pLELC patients for the first time, providing new insights to deepening our understanding of this rare EBV-associated primary lung carcinoma. Importance Pulmonary lymphoepithelioma-like carcinoma (pLELC) is a rarely distinctive subtype of primary lung cancer closely associated with Epstein-Barr virus (EBV) infection. Here, we gave the first overview of pLELC-derived EBV at the level of genome, methylation and transcription. We obtained the EBV sequences dataset from 78 primary pLELC patients, and revealed the sequences diversity across EBV genome and detected variability in known immune epitopes. Genome-wide association analysis combining 217 healthy controls identifies significant variations related to the risk of pLELC. Meanwhile, we characterized the integration landscapes of EBV at the genome-wide level. These results provided new insight for understanding EBV's role in pLELC tumorigenesis.

Epstein–Barr Virus Epithelial Cancers—A Comprehensive Understanding to Drive Novel Therapies

Epstein–Barr virus (EBV) is a ubiquitous oncovirus associated with specific epithelial and lymphoid cancers. Among the epithelial cancers, nasopharyngeal carcinoma (NPC), lymphoepithelioma-like carcinoma (LELC), and EBV-associated gastric cancers (EBVaGC) are the most common. The role of EBV in the pathogenesis of NPC and in the modulation of its tumour immune microenvironment (TIME) has been increasingly well described. Much less is known about the pathogenesis and tumour–microenvironment interactions in other EBV-associated epithelial cancers. Despite the expression of EBV-related viral oncoproteins and a generally immune-inflamed cancer subtype, EBV-associated epithelial cancers have limited systemic therapeutic options beyond conventional chemotherapy. Immune checkpoint inhibitors are effective only in a minority of these patients and even less efficacious with molecular targeting drugs. Here, we examine the key similarities and differences of NPC, LELC, and EBVaGC and comprehensively describe the clinical, pathological, and molecular characteristics of these cancers. A deeper comparative understanding of these EBV-driven cancers can potentially uncover targets in the tumour, TIME, and stroma, which may guide future drug development and cast light on resistance to immunotherapy.

Simiao Qingwen Baidu decoction inhibits Epstein-Barr virus-induced B lymphoproliferative disease and lytic viral replication

CONTEXT

Simiao Qingwen Baidu decoction (SQBD), a traditional Chinese medicine prescription, can ameliorate Epstein-Barr virus (EBV) induced disease. However, its mechanism still remains unknown.

OBJECTIVE

To detect the mechanism of SQBD in EBV-induced B lymphoproliferative disease in vitro.

MATERIALS AND METHODS

Sprague-Dawley (SD) rats (n = 20) were given SQBD (10 mL/kg) by gavage once a day for 7 d. SQBD-containing serum was obtained from abdominal aortic blood of rats, and diluted with medium to obtain 5%, 10% or 20%-medicated serum. SD rats (n = 10) were given normal saline, and normal serum was collected as a control. EBV-transformed B cells (CGM1) were cultured in medium containing 5%, 10% or 20%-medicated serum. CGM1 cells were treated with normal serum as a control. Cell viability and apoptosis were examined. The expression and activity of proteins were assessed.

RESULTS

We found that IC₅₀ (83 ± 26.07%, 24 h; 69.88 ± 4.69%, 48 h) of 10% medicated serum was higher than that of 5% (25.47 ± 6.98%, 24 h; 21.62 ± 7.30%, 48 h) and 20%-medicated serum (51 ± 7.25%, 24 h; 56.03 ± 2.56%, 48 h). Moreover, SQBD promoted apoptosis of CGM1 cells by regulating EBV latency proteins expression. SQBD inhibited EBV-induced lytic viral replication.

CONCLUSIONS

Our data confirmed that SQBD inhibits EBV-induced B lymphoproliferative disease and lytic viral replication. This work provides a theoretical basis for the mechanism of SQBD in EBV-induced B lymphoproliferative disease, and SQBD may be an effectively therapeutic drug for EBV-induced B lymphoproliferative disease.

A Rare Subtype of Non-small Cell Lung Cancer: Report of 159 Resected Pathological Stage I-IIIA Pulmonary Lymphoepithelioma-Like Carcinoma Cases

Background: The current study analyzed resected stage I–IIIA pulmonary lymphoepithelioma-like carcinoma (LELC) cases to define the clinical characteristics, prognosis and long-term outcomes of resected LELC, with the purpose of guiding clinical management for this rare tumor.

Methods: Resected stage I–IIIA LELC, adenocarcinoma (ADC) and squamous cell carcinoma (SCC) cases from our center were enrolled. Propensity score matching (PSM) was applied to minimize the selection bias. Overall survival (OS) and disease-free survival (DFS) were compared between groups. Multivariate analyses were performed to identify the prognostic factors, and a nomogram was developed.

Results: A total of 159 LELCs, 2,757 ADCs, and 1,331 SCCs were included. LELC, dominated among younger patients and non-smokers. LELC was a poorly differentiated disease that lacked driver gene mutations and was positive for immunohistochemistry indicators of squamous cell lineage. Survival analyses revealed that OS was significantly better for LELC than for other common non-small cell lung cancers (NSCLCs) both before PSM (all P < 0.001) and after PSM (all P < 0.05). Further analyses revealed that early pathological node stage and preoperative albumin level ≥35 were identified as independent prognostic factors favoring OS and DFS.

Conclusions: LELC, dominated among younger and non-smoking populations, lacked driver gene mutations and was positive for immunohistochemistry indicators of squamous cell lineage. The survival outcome of LELC was better than other common NSCLCs.

Molecular and Clinical Characteristics of Primary Pulmonary Lymphoepithelioma-Like Carcinoma

Objectives: Primary pulmonary lymphoepithelioma-like carcinoma (PPLELC) is an extremely rare subtype of non-small cell lung cancer (NSCLC). Currently, there are no established treatment protocols due to rarity of the cancer. Thus, this study aimed to explore the molecular and clinical characteristics of PPLELC.

Study design and setting: Data from patients with PPLELC who were admitted to Zhejiang Cancer Hospital from August 2009 to September 2020 were retrospectively collected. Next-generation sequencing was performed to obtain a genomic profile and tumor mutation burden (TMB) value of patients with adequate tissue and divided them into two groups according to the expression level of PD-L1. The correlation of PD-L1 expression and the clinicopathological characteristics was evaluated by Pearson Chi-square test. Kaplan-Meier curves was applied to present the probability of survival between PD-L1 expression level and overall survival (OS). Moreover, the literature on the immunotherapy of advanced PPLELC published in PubMed between 2016 and 2020 were reviewed and the efficacy of immunotherapy were analyzed.

Results: A total of 18 patients pathologically diagnosed as PPLELC were included. After a follow-up period of 8.8–138 months, 14 patients survived, three patients died and one patient lost, the median OS was 45.3 months Seven samples (tissue-available) tested by NGS and the median TMB was 2.5 mutations/Mb. 19 somatic mutated genes were recognized and TP53 (43%) and CYLD (43%) were the two most commonly mutated genes. Only seven patients who underwent NGS were tested for PD-L1. Three patients with high PD-L1 expression (PD-L1≥ 50%) and four patients with low PD-L1 expression (PD-L1 <50%) were included. No significant correlation was observed between PD-L1 expression and clinical characteristics (age, gender, smoking status, tumor stage, lymph node metastasis) (p > 0.05) and OS (p = 1). What’s more, 10 PPLELC patients involved in previous studies and one patient received nivolumab in the current study were collected retrospectively. 4/11 (36.4%) patients achieved PR, 6/11 (54.5%) patients achieved SD, and 1/11 (9.1%) patients achieved PD and the disease control rate (DCR) was 90.9%.

Conclusions: The prognosis of PPLELC is better than that of other NSCLC, and immunotherapy may be a promising treatment to prolong the survival of advanced PPLELC patients. Whether the immunotherapy efficacy of PPLELC can be predicted by PD-L1 and TMB needs further clinical investigation. CYLD genetic alterations may participate in Epstein–Barr virus-mediated tumorigenesis in PPLELC, providing a novel therapeutic target.

Whole-exome Sequencing of Epstein-Barr Virus-associated Pulmonary Carcinoma With Low Lymphocytic Infiltration Shows Molecular Features Similar to Those of Classic Pulmonary Lymphoepithelioma-like Carcinoma: Evidence to Support Grouping Together as One Disease Entity

Pulmonary lymphoepithelioma-like carcinoma (LELC) is a distinct type of Epstein-Barr virus (EBV)-associated non-small cell carcinoma characterized by a syncytial growth pattern with heavy lymphocytic infiltration. We recently identified a group of non-small cell carcinomas, which are also associated with EBV but lack significant lymphocytic infiltration. These EBV-associated pulmonary carcinomas with low lymphocytic infiltration morphologically resemble nonkeratinizing squamous cell carcinoma, but their patient characteristics are more similar to those of LELC, including female sex and nonsmoking status. To clarify the relationships between these disease entities, in this study, we explored the molecular characteristics of the EBV-associated carcinomas with low lymphocytic infiltration using whole-exome sequencing and compared their molecular profiles with those of classic LELC and pulmonary squamous cell carcinoma. We demonstrate that the molecular characteristics of EBV-associated carcinomas with low lymphocytic infiltration are highly similar to those of classic LELC. Both show low tumor mutational burden, lack of commonly mutated driver genes in other types of non-small cell lung cancer, similar mutational signature involving APOBEC-related mutations, and enrichment of CD274 (programmed death-ligand 1) amplification. These molecular characteristics are very different from those of pulmonary squamous cell carcinoma. The unique patient demographics and molecular characteristics shared by EBV-associated carcinomas with low lymphocytic infiltration and classic LELC suggest that these tumors represent one single disease entity defined by EBV association. This study supports the proposal for the usage of the term "EBV-associated pulmonary carcinoma" to encompass the entire morphologic spectrum of this distinct EBV-associated disease entity.

Thymic Lymphoepithelial Carcinoma Associated with Epstein-Barr Virus: Experiences and Literature Review

Thymic lymphoepithelial carcinoma (TLEC) is a primary thymic carcinoma that accounts for about 14% of all thymic epithelial tumors and is classified into 14 types. The histological morphology is similar to lymphoepithelioma, a type of undifferentiated nasopharyngeal carcinoma. It has been reported that squamous carcinoma accounts for approximately 80% of thymic carcinoma, followed by TLEC, which accounts for 6%. TLEC has been reported to be associated with Epstein-Barr virus (EBV), with EBV infection in TLEC tumor cells first noted by Lyvraz et al. in 1985. Tumors shown to be EBV-positive are classified as TLEC if lymphoplasmacytic infiltration is lacking. However, only about 50% of the cases are positive for EBV, which is lower compared to nasopharyngeal lymphoepithelioma. Instances of EBV infection in other types of thymic epithelial tumor have been reported at lower rates, which suggests that EBV infection may have an important influence on the carcinogenesis of TLEC, though the etiology is unknown. TLEC is a highly malignant tumor with poor prognosis, as affected patients have a median survival time of 22 months, according to 58 cases from the literature, while the 5-year survival rate is 34.4%. Presently, prognosis is not considered to be affected by the presence or absence of EBV positivity.

Role of Virus-Induced Host Cell Epigenetic Changes in Cancer

The tumor viruses human T-lymphotropic virus 1 (HTLV-1), hepatitis C virus (HCV), Merkel cell polyomavirus (MCPyV), high-risk human papillomaviruses (HR-HPVs), Epstein-Barr virus (EBV), Kaposi’s sarcoma-associated herpes virus (KSHV) and hepatitis B virus (HBV) account for approximately 15% of all human cancers. Although the oncoproteins of these tumor viruses display no sequence similarity to one another, they use the same mechanisms to convey cancer hallmarks on the infected cell. Perturbed gene expression is one of the underlying mechanisms to induce cancer hallmarks. Epigenetic processes, including DNA methylation, histone modification and chromatin remodeling, microRNA, long noncoding RNA, and circular RNA affect gene expression without introducing changes in the DNA sequence. Increasing evidence demonstrates that oncoviruses cause epigenetic modifications, which play a pivotal role in carcinogenesis. In this review, recent advances in the role of host cell epigenetic changes in virus-induced cancers are summarized.

Prognostic Significance of Regional/Systemic Metabolic Parameters on 18F-FDG PET in Pulmonary Lymphoepithelioma-Like Carcinoma

Background

Pulmonary lymphoepithelioma-like carcinoma (LELC) is a rare subtype of lung cancer with less than 700 cases being reported in the literature, and no specialized treatment guidelines have been established. The prognostic significance of metabolic parameters on ¹⁸F-FDG PET in pulmonary LELC still remains unknown.

Methods

From July 2011 to September 2020, 76 pulmonary LELC patients undergoing pre-treatment ¹⁸F-FDG PET imaging were enrolled, and PET parameters including maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were calculated. In addition, whole-body tumor burdens were categorized into primary tumor lesion (PRL), thoracic lymph-node lesion (TRLN), and distant metastasis (DM) for respective metabolic parameters acquisition. ROC curves were generated to evaluate the predictive performance of the PET parameters, and correlations between tumor burdens of the different regional lesions were analyzed using linear correlation analysis. The prognostic significance for progression-free survival (PFS) and overall survival (OS) was assessed using univariate and multivariate survival analyses.

Results

Tumor stage, pre-/post-treatment serum EBV-DNA copies, SUVmax (cutoff 17.5), MTV, and TLG were significantly associated with PFS and OS in univariate analysis. MTV and TLG (AUC = 0.862 and 0.857, respectively) showed significantly higher predictive value than SUVmax (AUC = 0.754) and remained independent prognostic indicators for PFS in multivariate analysis (P = 0.026 and 0.019, respectively). Besides, non-colinearity was detected between metabolic burdens of the different regional lesions. MTV_-PRL, MTV_-DM, TLG_-PRL, and TLG_-DM were identified to be independent prognostic factors for PFS and OS, whereas MTV_-TRLN and TLG_-TRLN were not.

Conclusion

The study demonstrated that MTV and TLG had independent prognostic significance for pulmonary LELC, which supported the incorporation of ¹⁸F-FDG PET imaging into clinical treatment protocols for pulmonary LELC and implied multi-disciplinary cooperation for primary and distant metastatic lesions to further improve prognosis.