Primary pulmonary lymphoepithelioma-like carcinoma

A Novel Inflammation-Marker-Based Prognostic Model for Advanced Pulmonary Lymphoepithelioma-Like Carcinoma

Purpose

This study aimed to investigate the prognostic value of inflammation markers for advanced pulmonary lymphoepithelioma-like carcinoma (PLELC) and develop an effective prognostic model based on inflammation markers to predict the overall survival (OS) of this population.

Methods

Cox regression analysis was performed on 18 clinical and inflammation features, and a nomogram was created to predict overall survival (OS). The nomogram was evaluated by the concordance index (C-index), the time-dependent area under the receiver operating (ROC) curves (AUCs), calibration curves, and Decision Curve Analysis (DCA).

Results

This study included a training cohort (n = 177) and a validation cohort (n = 77). The following variables were found to be independent prognostic factors for OS and used in the nomogram: Hepatitis B virus surface antigen status, gender, neutrophil-to-lymphocyte ratio (NLR), and C-reactive protein-to-albumin ratio (CAR). The C-indexes of the nomogram in the training and validation cohort were 0.740 (95% CI: 0.706-0.747) and 0.733 (95% CI: 0.678-0.788), respectively. Furthermore, time-dependent AUCs and well-fitted calibration curves showed good discriminative ability in both cohorts. Additionally, among the subset of EBV DNA data (n = 111), both ROC curve and DCA curve analysis demonstrated that the nomogram plus EBV DNA provided superior predictive performance compared to EBV DNA or the nomogram alone. Patients who received chemoimmunotherapy as the first-line treatment had better OS (not reached vs 44.4 months, P = 0.015) than those with chemotherapy alone and those who received immunotherapy at any line had better OS than those who never received it (not reached vs 31.0 months, P < 0.001).

Conclusion

This study established and validated a prognostic nomogram model for patients with advanced PLELC. Combining the nomogram with EBV DNA more effectively predicted the prognosis of patients than the nomogram alone. Immunotherapy was found to be a critical treatment option for PLELC.

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.

N6-methyladenosine methylation regulatory pattern of pulmonary lymphoepithelioma-like carcinoma based on exosomal transcriptome analysis

Pulmonary lymphoepithelioma-like carcinoma (pLELC) is a rare malignancy that lacks specific biomarkers. N6-methyladenosine (m6 A) is the most widespread internal modification of messenger RNA (mRNA), and its dysregulation is involved in the development of many cancers. However, the expression of m6 A genes in pLELC and their roles are unknown. We obtained an exosomal transcriptome data set of patients diagnosed with pLELC and healthy controls using RNA sequencing and identified differentially expressed genes (DEGs) in the two groups using R software. The differential expression of the 37 m6 A genes in the two sets of samples was further analyzed, and receiver operating characteristic (ROC) curves were plotted for each gene to identify their grouping ability. The STRING database was used to construct a protein-protein interaction network for m6 A genes. An mRNA-miRNA regulatory network of m6 A-related DEGs was constructed using the miRNet database, and a prediction score formula was established. A nomogram was constructed based on the candidate m6 A genes and prediction scores. The expression of key genes was determined through the immunohistochemical (IHC) staining of clinical tissue sections. Using ROC curves, nine m6 A genes were revealed to have classification efficacy in both groups of samples. We screened seven m6 A-related DEGs (MAN2C1, HNRNPCL1, FUS, EIF6, DIP2A, COA3, and BUD13) that were beneficial for grouping and constructed nomogram models. Through IHC, we identified FUS and EIF6 as being possibly involved in the occurrence and development of pLELC. The m6 A gene expression patterns in pLELC-derived exosomes were significantly different from those in healthy controls. We screened several key genes to facilitate the development of diagnostic markers for pulmonary lymphoepithelioma.

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.

Novel Multimodal Management of Post-Partum Synchronous Metastatic Pulmonary EBV-Associated Lymphoepithelioma-Like Carcinoma (LELC)-A Case Report

Primary Epstein-Barr-Virus (EBV)-associated pulmonary lymphoepithelioma-like carcinoma (LELC) is an aggressive rare cancer. Higher incidences have been observed in Asian sub-populations. Multimodal treatment paradigms have emerged as promising novel strategies in the management of advanced NSCLC. In this report, we describe the case of a 34-year-old female patient of Asian origin with a post-partum initial diagnosis of pulmonary LELC. Multimodal treatment with chemoimmunotherapy and hypofractionated irradiation to the primary tumour and main metastatic sites led to a favourable response demonstrating that radiotherapy may potentially augment anti-tumour immunity. To the best of our knowledge, this is the first case report on this novel therapy strategy of multi-site hypofractionated radiotherapy and chemoimmunotherapy for metastatic pulmonary EBV-associated LELC.

Immune Checkpoint Blockade Therapy May Be a Feasible Option for Primary Pulmonary Lymphoepithelioma-like Carcinoma

Primary pulmonary lymphoepithelioma-like carcinoma (PPLELC) is a rare subtype of non-small cell lung cancer (NSCLC) for which there is currently no recognized treatment. Recently, favorable immune checkpoint blockade responses have been observed in PPLELC. This study aimed to review the effects of this regimen in patients with advanced PPLELC. PPLELC patients treated with immune checkpoint inhibitors at West China Hospital between January 2008 and December 2019 were retrospectively identified. Demographic parameters and antitumor treatment details were retrieved and reviewed. Among 128 patients diagnosed with PPLELC, 5 who received immune checkpoint inhibitors at advanced stages were included in the analysis. All of these patients were female nonsmokers with a median age of 55.6 (range 53-58) years at diagnosis. Their median PD-L1 expression was 40% (range, 30-80%). Although the patients underwent surgeries, chemotherapy and radiotherapy, all the treatments failed. Immune checkpoint inhibitors were administered palliatively, and three patients responded favorably, with the best overall response being partial remission (PR). Thus, immune checkpoint inhibitors may be a promising treatment for advanced PPLELC, and large clinical trials are warranted to obtain more evidence regarding this regimen.

Molecular characteristics of primary pulmonary lymphoepithelioma-like carcinoma based on integrated genomic analyses

Primary pulmonary lymphoepithelioma-like carcinoma (pLELC) is a rare non-small cell lung cancer (NSCLC) subtype. Clinical features have been described in our previous report, but molecular characteristics remain unclear. Herein, pLELC genomic features were explored. Among 41,574 lung cancers, 128 pLELCs and 162 non-pLELC NSCLCs were enrolled. Programmed cell death ligand 1 (PD-L1) and protein 53 (p53) expression was detected in 47 surgically resected pLELC samples by immunohistochemical assays. Multiomics genomic analyses, including whole-genome sequencing (WGS), RNA whole-transcriptome sequencing (RNA-seq), and Epstein-Barr virus (EBV) integration analyses, were performed on eight frozen pLELC tissues and compared with 50 lung adenocarcinomas (LUADs) and 50 lung squamous cell carcinomas (LUSCs) from The Cancer Genome Atlas (TCGA) and another 26 EBV-positive nasopharynx cancers (EBV⁺-NPCs). Progression-free survival (PFS) and overall survival (OS) of pLELC patients were better than those of non-pLELC patients. High PD-L1 or p53 expression was associated with extended disease-free survival (DFS). pLELC had 14 frequently mutated genes (FMGs). Somatically mutated genes and enrichment of genetic lesions were found, which differed from observations in LUAD, LUSC, and EBV⁺-nasopharyngeal carcinoma (NPC). Three tumor-associated genes, zinc finger and BTB domain-containing 16 (ZBTB16), peroxisome proliferator activated receptor gamma (PPARG), and transforming growth factor beta receptor 2 (TGFBR2), were downregulated with copy number variation (CNV) loss. EBV was prone to integrating into intergenic and intronic regions with two upregulated miR-BamH1-A rightward transcripts (BARTs), BART5-3P and BART20-3P. Our findings reveal that pLELC has a distinct genomic signature. Three tumor-associated genes with CNV loss and two miR-BARTs might be involved in pLELC tumorigenesis.

SSTR2a is constantly expressed in lymphoepithelioma-like carcinoma with squamous differentiation other than that with glandular differentiation

AIMS

Somatostatin receptor 2a (SSTR2a) is an important diagnostic marker of meningioma and neuroendocrine tumours and is frequently expressed in primary and metastatic non-keratinising nasopharyngeal carcinoma (NK-NPC). Since NK-NPC cases are considered a kind of lymphoepithelioma-like carcinoma (LELCs) which originate from the nasopharynx, information on the expression profile of SSTR2a in LELC in other sites with squamous and glandular differentiations is still lacking. This study aimed to assess the expression of SSTR2a in LELC of various organs and clarify its expression profile.

METHODS

Expression of SSTR2a in 164 cases of LELC was retrospectively analysed by immunohistochemistry in paraffin-embedded tissues, including 146 cases of LELC with squamous differentiation (120 cases of the nasopharynx, 21 cases of the lung and 5 cases of the parotid gland) and 18 cases of LELC with glandular differentiation (15 cases of the stomach and 3 cases of the liver).

RESULTS

We found that all (100%) cases of LELC of the lung (21/21) and parotid gland (5/5), and 93.3% (112/120) cases of LELC of the nasopharynx showed a diffused and strong expression of SSTR2a, while cases of gastric (0/15) and biliary (0/3) showed no SSTR2a expression.

CONCLUSION

SSTR2a is constantly expressed in LELC with squamous differentiation, but not expressed in LELC with glandular differentiation. However, the selective expression mechanism of SSTR2a remains unknown, which needs further investigation. Our novel findings might provide potential therapeutic approaches for the treatment of LELC with squamous cell differentiation.