Pleural effusions associated with squamous cell lung carcinoma have a low diagnostic yield and a poor prognosis

Contribution of crosstalk of mesothelial and tumoral epithelial cells in pleural metastasis of lung cancer

Background

Tumor metastasis commonly affects pleura in advanced lung cancer and results in malignant pleural effusion (MPE). MPE is related to poor prognosis, but without systematic investigation on different cell types and their crosstalk at single cell resolution.

Methods

We conducted single-cell RNA-sequencing (scRNA-seq) of lung cancer patients with pleural effusion. Next, our data were integrated with 5 datasets derived from individuals under normal, non-malignant disease and lung carcinomatous conditions. Mesothelial cells were re-clustered and their interactions with epithelial cells were comprehensively analyzed. Taking advantage of inferred ligand-receptor pairs, a prediction model of prognosis was constructed. The co-culture of mesothelial cells and malignant epithelial cells in vitro and RNA-seq was performed. Epidermal growth factor receptor (EGFR) antagonist cetuximab was utilized to prevent the lung cancer cells' invasiveness. Spatial distribution of cells in lung adenocarcinoma patients' samples were also analyzed to validate our findings.

Results

The most distinctive transcriptome profiles between tumor and control were revealed in mesothelial cells, which is the predominate cell type of pleura. Five subtypes were divided, including one predominately identified in MPE which was characterized by enriched cancer-related pathways (e.g., cell migration) along evolutionary trajectory from normal mesothelial cells. Cancer-associated mesothelial cells (CAMCs) exhibited varied interactions with different subtypes of malignant epithelial cells, and multiple ligands/receptors exhibited significant correlation with poor prognosis. Experimentally, mesothelial cells can increase the migration ability of lung cancer cells through co-culturing. EGFR was the only affected gene in cancer cells that exhibited interaction with mesothelial cells and was associated with poor prognosis. Using EGFR antagonist cetuximab prevented the lung cancer cells' increased invasiveness caused by mesothelial cells. Moreover, epithelial mitogen (EPGN)-EGFR interaction was supported through spatial distribution analysis, revealing the significant proximity between EPGN+ mesothelial cells and EGFR+ epithelial cells.

Conclusions

Our findings highlighted the important role of mesothelial cells and their interactions with cancer cells in pleural metastasis of lung cancer, providing potential targets for treatment.

High Yield of Pleural Cell-Free DNA for Diagnosis of Oncogenic Mutations in Lung Adenocarcinoma

BACKGROUND

Pleural cytology is currently used to assess targetable mutations in patients with advanced lung adenocarcinoma. However, it is fraught with low diagnostic yield.

RESEARCH QUESTION

Can pleural cell-free DNA (cfDNA) be used to assess targetable mutations in lung adenocarcinoma patients with malignant pleural effusions (MPE)?

STUDY DESIGN AND METHODS

Patients with lung adenocarcinoma MPE were recruited prospectively between January 2017 and September 2021. Oncogenic mutations were assessed by treating providers using pleural fluid cytology or lung cancer biopsies. Pleural and plasma cfDNA were used to assess the mutations using next-generation sequencing (NGS).

RESULTS

Fifty-four pleural fluid samples were collected from 42 patients. The diagnostic yield to detect oncogenic mutations for pleural cfDNA, pleural cytology, biopsy, and plasma cfDNA was 49/54 (90.7%), 16/33 (48.5%), 22/25 (88%), and 24/32 (75%), respectively, P < .001. The agreement of mutations in positive samples between pleural cfDNA and pleural cytology was 100%, whereas the agreement of pleural cfDNA with biopsies was 89.4%. The median concentration (interquartile range) of pleural cfDNA was higher than plasma: 28,444 (4,957-67,051) vs 2,966.5 (2,167-5,025) copies of amplifiable DNA per mL, P < .01. Median of 5 mL (interquartile range, 4.5-5) of pleural fluid supernatant was adequate for cfDNA testing.

INTERPRETATION

The diagnostic yield of pleural cfDNA NGS for oncogenic mutations in lung adenocarcinoma patients is comparable to tumor biopsies and higher than pleural cytology and plasma cfDNA. The pleural cfDNA can be longitudinally collected, can be readily incorporated in clinical workflow, and may decrease the need for additional biopsies.

NSCLC in the Era of Targeted and Immunotherapy: What Every Pulmonologist Must Know

The treatment of non-small cell lung cancer has dramatically changed over the last decade through the use of targeted therapies and immunotherapies. Implementation of these treatment regimens relies on detailed knowledge regarding each tumor’s specific genomic profile, underscoring the necessity of obtaining superior diagnostic tissue specimens. While these treatment approaches are commonly utilized in the metastatic setting, approval among earlier-stage disease will continue to rise, highlighting the importance of early and comprehensive biomarker testing at the time of diagnosis for all patients. Pulmonologists play an integral role in the diagnosis and staging of non-small cell lung cancer via sophisticated tissue sampling techniques. This multifaceted review will highlight current indications for the use of targeted therapies and immunotherapies in non-small cell lung cancer and will outline the quality of various diagnostic approaches and subsequent success of tissue biomarker testing. Pulmonologist-specific methods, including endobronchial ultrasound and guided bronchoscopy, will be examined as well as other modalities such as CT-guided transthoracic biopsy and more.

Association between clinical outcomes and local treatment in stage IV non-small cell lung cancer patients with single extrathoracic metastasis

Background

Local treatment (LT) such as radiotherapy and metastasectomy on metastatic sites may improve outcomes in oligometastatic NSCLC patients, but more data are necessary to support LT in oligometastatic diseases. Patients with single extrathoracic metastatic lesion are more likely to benefit from local therapy. In this study, we evaluated the impact of LT in NSCLC patients with a single extrathoracic metastatic lesion.

Methods

Data were obtained from the Korean Association for Lung Cancer Registry (KALC‐R), a database created using a retrospective sampling survey by the Korean Central Cancer Registry (KCCR) and the Lung Cancer Registration Committee.

Results

A total of 787 NSCLC patients with a single extrathoracic metastatic lesion were evaluated. In the multivariate analysis for OS, age, female sex, poor performance score, squamous histological subtype, LT, and initial treatment modality showed significant associations. Regarding LT, groups that underwent curative LT were significantly associated with better OS compared to groups that did not undergo LT (p = 0.011, HR 0.448, 95% CI: 0.242–0.829). In the multivariate analysis of patients who underwent LT, poor performance score, initial treatment modality, and T stage were independently associated with poor OS. Compared to the T1 stage, T3 stage showed an HR of 2.470 (95% CI: 1.309–4.663; p = 0.005) and T4 stage showed an HR of 2.063 (95% CI: 1.093–3.904; p = 0.026).

Conclusion

In NSCLC with a single extrathoracic metastatic lesion, LT, especially for curative purposes, has an independent association with OS. Moreover, among the patients who received LT, factors such as T stage, poor performance score, and initial treatment modality were significantly associated with OS.

Diagnostic value of periostin in lung cancer-related malignant pleural effusion

BACKGROUND

Periostin (POSTN) is an extracellular matrix protein that is overexpressed in lung cancer and is considered an effective diagnostic and prognostic biomarker for lung cancer. The purpose of this study was to investigate the diagnostic performance of POSTN and to further evaluate the diagnostic value of POSTN combined with carcinoembryonic antigen (CEA) and cancer ratio [CR: serum lactate dehydrogenase (LDH)/pleural effusion adenosine deaminase (PE ADA)] in lung cancer-related malignant PE (MPE).

METHODS

A total of 108 patients with PE, including 54 with lung cancer and 54 with benign lung disease, were enrolled in this study. The POSTN levels of PE and serum were detected using an enzyme-linked immunosorbent assay. Information on the expression of PE and serum CEA, serum LDH, and PE ADA was collected from medical records.

RESULTS

The levels of PE POSTN in MPE of patients with lung cancer were significantly higher than those in patients with benign PE (p < 0.0001). The receiver operating characteristic (ROC) curve indicated that the diagnostic sensitivity and specificity of PE POSTN for lung cancer-related MPE were respectively 77.78% and 68.52% when the cutoff value was determined to be 53.45 ng/ml. The ROC curve analysis demonstrated that PE POSTN has a high diagnostic value in MPE associated with lung cancer [area under the curve (AUC) = 0.764], and the combination of PE POSTN, PE CEA, and CR can improve the diagnostic accuracy of lung cancer-related MPE (AUC = 0.948).

CONCLUSION

POSTN can be used as a potential marker for lung cancer-related MPE diagnosis.