Immune Checkpoint Inhibitors for the Treatment of Unresectable Stage III Non-Small Cell Lung Cancer: Emerging Mechanisms and Perspectives

Comparison of post-chemoradiotherapy pneumonitis between Asian and non-Asian patients with locally advanced non-small cell lung cancer: a systematic review and meta-analysis

Background

Pneumonitis is a common complication for patients with locally advanced non-small cell lung cancer undergoing definitive chemoradiotherapy (CRT). It remains unclear whether there is ethnic difference in the incidence of post-CRT pneumonitis.

Methods

PubMed, Embase, Cochrane Library, and Web of Science were searched for eligible studies from January 1, 2000 to April 30, 2023. The outcomes of interest were incidence rates of pneumonitis. The random-effect model was used for statistical analysis. This meta-analysis was registered with PROSPERO (CRD42023416490).

Findings

A total of 248 studies involving 28,267 patients were included. Among studies of CRT without immunotherapy, the pooled rates of pneumonitis for Asian patients were significantly higher than that for non-Asian patients (all grade: 66.8%, 95% CI: 59.2%-73.9% vs. 28.1%, 95% CI: 20.4%-36.4%; P < 0.0001; grade ≥2: 25.1%, 95% CI: 22.9%-27.3% vs. 14.9%, 95% CI: 12.0%-18.0%; P < 0.0001; grade ≥3: 6.5%, 95% CI: 5.6%-7.3% vs. 4.6%, 95% CI: 3.4%-5.9%; P = 0.015; grade 5: 0.6%, 95% CI: 0.3%-0.9% vs. 0.1%, 95% CI: 0.0%-0.2%; P < 0.0001). Regarding studies of CRT plus immunotherapy, Asian patients had higher rates of all-grade (74.8%, 95% CI: 63.7%-84.5% vs. 34.3%, 95% CI: 28.7%-40.2%; P < 0.0001) and grade ≥2 (34.0%, 95% CI: 30.7%-37.3% vs. 24.6%, 95% CI: 19.9%-29.3%; P = 0.001) pneumonitis than non-Asian patients, but with no significant differences in the rates of grade ≥3 and grade 5 pneumonitis. Results from subgroup analyses were generally similar to that from the all studies. In addition, the pooled median/mean of lung volume receiving ≥20 Gy and mean lung dose were relatively low in Asian studies compared to that in non-Asian studies.

Interpretation

Asian patients are likely to have a higher incidence of pneumonitis than non-Asian patients, which appears to be due to the poor tolerance of lung to radiation. Nevertheless, these findings are based on observational studies and with significant heterogeneity, and need to be validated in future large prospective studies focusing on the subject.

Funding

None.

The Meaning of Lymphadenopathies During Adjuvant Durvalumab After Chemoradiotherapy for Lung Cancer: Thinking Beyond Disease Progression

Immune-checkpoint inhibitors (ICIs) have become the mainstay of treatment for many malignancies. With this new strategy, relevant immune-related adverse events (irAEs) have been reported, some of which can be mistaken for disease progression. To better illustrate the current challenges in diagnosing and managing a patient under adjuvant ICI treatment, we present the case of a 67-year-old female patient with stage IIIB unresectable, epidermal growth factor receptor (EGFR)-mutated, non-small-cell lung cancer who was initially treated with chemoradiotherapy, followed by immunotherapy with durvalumab. During the course of immunotherapy, the patient presented with madarosis and erythematous and endured skin lesions, in addition to lymphadenopathies and pulmonary infiltrates. She was started on first-line palliative treatment with an EGFR tyrosine kinase inhibitor. After reviewing the case, a multidisciplinary team meeting suggested diagnostic procedures, including a transbronchial needle aspiration from mediastinal lymph nodes. The histologic examination showed chronic systemic inflammation and non-caseating granulomas of the sarcoid type. In this case, palliative treatment was suspended and systemic therapy with prednisolone was initiated. The patient became asymptomatic and the previously observed radiologic abnormalities resolved. This case highlights the importance of early recognition and appropriate treatment of irAEs, mainly because these conditions remain poorly understood and are probably underdiagnosed. Considering differential diagnosis is paramount to guide clinical management, despite curative or palliative treatment intent.

Real-World Journey of Unresectable Stage III NSCLC Patients: Current Dilemmas for Disease Staging and Treatment

Daily-practice challenges in oncology have been intensified by the approval of immune checkpoint inhibitors (ICI). We aimed to outline current therapy policies and management of locally advanced unresectable stage III non-small-cell lung cancer (NSCLC) in different countries. One thoracic oncologist from each of the following countries—Belgium, Croatia, Greece, Israel, the Netherlands, Norway, Poland, Portugal, Romania, Slovenia, and Switzerland—participated in an electronic survey. Descriptive statistics were conducted with categorical variables reported as frequencies and continuous variables as median and interquartile range (IQR) (StataSE-v15). EBUS (endobronchial ultrasound bronchoscopy) was used either upfront or for N2 confirmation. Resectability is still a source of disagreement; thus, decisions vary within each multidisciplinary team. Overall, 66% of stage III patients [IQR 60–75] undergo chemoradiation therapy (CRT); concurrent CRT (cCRT) accounts for most cases (~70%). Performance status is universally used for cCRT eligibility. Induction chemotherapy is fairly weighted based on radiotherapy (RT) availability. Mean time to evaluation after RT completion is less than a month; ICI consolidation is started within six weeks. Durvamulab expenditures are reimbursed in all countries, yet some limiting criteria exist (PD-L1 ≥ 1%, cCRT). No clear guidance on therapies at Durvamulab progression exist; experts agree that it depends on progression timing. Given the high heterogeneity in real-world practices, standardized evidence-based decisions and healthcare provision in NSCLC are needed.

Identification and Validation of a Tumor Microenvironment-Related Gene Signature for Prognostic Prediction in Advanced-Stage Non-Small-Cell Lung Cancer

The development of immunotherapy has greatly changed the advanced-stage non-small-cell lung cancer (NSCLC) treatment landscape. The complexity and heterogeneity of tumor microenvironment (TME) lead to discrepant immunotherapy effects among patients at the same pathologic stages. This study is aimed at exploring potential biomarkers of immunotherapy and accurately predicting the prognosis for advanced NSCLC patients. RNA-seq data and clinical information on stage III/IV NSCLC were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). In TCGA-NSCLC with stage III/IV (n = 192), immune scores and stromal scores were calculated by using the ESTIMATE algorithms. Univariate, LASSO, and multivariate Cox regression analyses were performed to screen prognostic TME-related genes (TMERGs) and constructed a gene signature risk score model. It was validated in external dataset including GSE41271 (n = 91) and GSE81089 (n = 36). Additionally, a nomogram incorporating TMERG signature risk score and clinical characteristics was established. Further, we accessed the proportion of 22 types of tumor-infiltrating immune cells (TIIC) from the CIBERSORT website and analyzed the difference between two risk groups. OS of patients with high immune/stromal scores were higher (log-rank P = 0.044/log-rank P = 0.048). Multivariate Cox regression identified six prognostic TMERGs, including CD200, CHI3L2, CNTN1, CTSL, FYB1, and SLC52A1. We developed a six-gene risk score model, which was validated as an independent prognostic factor for OS (HR: 3.32, 95% CI: 2.16-5.09). Time-ROC curves showed useful discrimination for TCGA-NSCLC cohort (1-, 2-, and 3-year AUCs were 0.718, 0.761, and 0.750). The predictive robustness was validated in the external dataset. The C-index and 1-, 2-, and 3-year AUCs of nomogram were the largest, which demonstrated the nomogram had the greatest predictive accuracy and effectiveness and could be used for clinical guidance. Besides, the increased infiltration of T cells regulatory (Tregs) and macrophages M2 in the high-risk group suggested that chronic inflammation may reduce survival probability in patients with advanced NSCLC. We conducted a comprehensive analysis of the tumor microenvironment and identified the TMERG signature, which could predict prognosis accurately and provide a reference for the personalized immunotherapy for advanced NSCLC patients.

Tissue MicroRNA Expression as a Predictor of Response to Immunotherapy in NSCLC Patients

Introduction

Expression of PD-L1 protein on tumor cells, which is so far the only validated predictive factor for immunotherapy, is regulated by epigenetic and genetic factors. Among the most important ones that regulate gene expression are microRNAs.

Materials and Methods

The study included 60 patients with NSCLC who underwent first or second line immunotherapy with pembrolizumab or nivolumab. FFPE materials were collected before the start of immunotherapy. We examined relative expression of microRNAs (miR-141, miR-200a, miR-200b, miR-200c, miR-429, miR-508-3p, miR-1184, miR-1255a) and PD-L1 mRNA expression. Copy number variation (CNV) of PD-L1 gene by qPCR and FISH methods were assessed. Two single nucleotide polymorphisms (SNPs) in promoter region of PD-L1 gene (rs822335 and rs822336) were examined. Expression of PD-L1 protein on tumor cells was assessed by immunohistochemistry (IHC). The response rate to immunotherapy and progression free survival (PFS) measured in weeks and overall survival (OS) measured in months from the start of immunotherapy were evaluated.

Results

Response to immunotherapy was observed in nine patients (15%, including one complete response), disease stabilization in 22 patients (36.7%), and progression in 29 patients (48.3%). Significantly higher (p=0.015) expression of miR-200b and significantly lower (p=0.043) expression of miR-429 were observed in responders compared to patients who did not respond to immunotherapy. The median PFS in the whole group of patients was 16 weeks, and the median OS was 10.5 month. In univariate analysis, the median PFS was significantly higher in patients with high miR-200b expression (HR=0.4253, 95%CI: 0.1737–1.0417, p=0.05) and high miR-508 expression (HR=0.4401, 95%CI: 0.1903–1.0178, p=0.05) and with low expression of miR-429 (HR=0.1288, 95%CI: 0.01727–0.9606, p=0.0456) compared to patients with low and high expression of these molecules, respectively. The median OS was higher in patients with low expression of miR-429 (HR=0,6288, 95%CI: 0,3053–1,2949, p=0.06) compared with patients with high expression of this microRNA. In multivariate analysis, we found that patients with PD-L1 expression on ≥1% of tumor cells compared to patients without PD-L1 expression on cancer cells had a significantly lower risk of progression (HR=0.3857, 95%CI: 0.1612–0.9226, p=0.0323) and death (HR=0.377, 95%CI: 0.1636–0.8688, p=0.022).

Conclusion

The miR-200b and miR-429 molecules in tumor cells seem to have greatest impact on the effectiveness of immunotherapy in NSCLC patients.

Efficacy and safety of immune checkpoint inhibitor consolidation after chemoradiation in patients of Asian ethnicity with unresectable stage III non-small cell lung cancer: Chinese multicenter report and literature review

BACKGROUND

The PACIFIC study has defined a new standard of care for patients with unresectable stage III non-small cell lung cancer (NSCLC) in the form of immune checkpoint inhibitor (ICI) consolidation therapy. However, there is little specific data pertaining to the safety and efficacy of this approach in Chinese NSCLC patients.

METHODS

This was a prospective multicenter cohort study. Between September 2018 and January 2020, patients with unresectable stage III NSCLC that had undergone chemoradiation therapy (CRT) and ICI consolidation treatment were enrolled in this study. The short-term safety, tolerability, and efficacy of ICI combination with CRT were evaluated in these patients.

RESULTS

Of the 20 Chinese patients eligible for inclusion, 17 (85.0%) underwent concurrent CRT treatment. In these patients, a median period of 40.5 days (range: 1-85 days) passed between the end of CRT and initiation of consolidation therapy. Pneumonitis occurred in 80.0% of patients, with seven (35.0%) being diagnosed with grade 1 pneumonitis and nine (45.0%) with grade 2 pneumonitis. No patients experienced grade 3 or higher pneumonitis or other ICI-related toxicities. Lung V20 ≥ 20% was associated with higher grade 2 pneumonitis (77.8%; ≥20% vs. 18.2%; <20%, P = 0.027). The overall response rate (ORR) in these patients was 95.0%. Over a median follow-up period of 11.3 months (range: 6.2-21.8 months), 12-month PFS of these patients were 89.5% (95% CI: 76.7-100.0%), and 12 months OS was 100.0%.

CONCLUSIONS

These data indicate that ICI consolidation therapy can achieve favorable short-term efficacy, while exhibiting good safety and acceptable toxicity profiles in Chinese patients with unresectable stage III NSCLC.

KEY POINTS

Significant findings of the study This is the first report evaluating the safety and efficacy of ICI consolidation therapy after chemoradiotherapy in China. Our results indicate that ICI consolidation is associated with favorable efficacy and no severe pneumonitis incidence in Chinese patients undergoing both anti-PD-1 and anti-PD-L1 monoclonal antibody consolidation. What this study adds Post-hoc analysis of the Japanese subgroup in the PACIFIC study suggested that consolidation therapy may be associated with increased pneumonitis incidence in Asian patients. However, our findings indicate that consolidation therapy is safe and tolerable in Chinese patients with unresectable stage III NSCLC.

Circular RNA circSLC25A16 contributes to the glycolysis of non-small-cell lung cancer through epigenetic modification

Growing evidence has highlighted the roles of circular RNAs (circRNAs) in non-small-cell lung cancer (NSCLC), however, their roles in NSCLC glycolysis remains poorly understood. CircRNAs microarray profiles discovered a novel exon-derived circRNA, circSLC25A16 (hsa_circ_0018534), in NSCLC tissue samples. In NSCLC samples, high-expression of circSLC25A16 was associated with unfavorable prognosis. Cellular experiments revealed that circSLC25A16 accelerated the glycolysis and proliferation of NSCLC cells. Besides, circSLC25A16 knockdown repressed the in vivo growth by xenograft assays. RNA-fluorescence in situ hybridization (RNA-FISH) illustrated that circSLC25A16 and miR-488-3p were both located in cytoplasm. Mechanistic experiments demonstrated that circSLC25A16 interacts with miR-488-3p/HIF-1α, which activates lactate dehydrogenase A (LDHA) by facilitating its transcription. Collectively, present research reveals the crucial function of circSLC25A16 on NSCLC glycolysis through miR-488-3p/HIF-1α/LDHA, suggesting the underlying pathogenesis for NSCLC and providing a therapeutic strategy for precise treatment.