Clinical observation of pulmonary lymphoepithelioma-like carcinoma

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.

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.