Immune checkpoint inhibitors for brain metastases in non-small-cell lung cancer: from rationale to clinical application

Immune checkpoint inhibitor (ICI) therapy in central nervous system cancers: State-of-the-art and future outlook

Invasive central nervous system (CNS) cancers are an area where the development of breakthrough therapies is urgently needed. For instance, conditions such as glioblastoma multiforme (GBM) are associated with poor clinical prognosis, with the majority of trials offering no improvement to marginally enhanced survival. Unleashing the potential of targeting the immune system in CNS cancers has gained attention in recent years. Inhibition of immune checkpoints such as CTLA-4, PD-1/PD-L1, TIM-3, and LAG-3 has been attempted in recent trials. While potentially offering a notable edge over other immunotherapies, multi-organ adverse events have been found with the administration of immune checkpoint inhibitors (ICIs). The present review captures the state-of-the-art evidence on ICI treatments in different CNS cancers. Also, we discuss the value of combinational therapies involving ICIs as well as next-generation therapeutics such as bispecific antibodies targeting PD-1/LAG-3/TIM-3 and CRISPR-Cas9-edited PD-1-knock-out checkpoint-resistant CAR T-cells.

Advances and challenges in cancer immunotherapy: Strategies for personalized treatment

Cancer immunotherapy has transformed oncology by harnessing the immune system to specifically target cancer cells, offering reduced systemic toxicity compared to traditional therapies. This review highlights key strategies, including adoptive cell transfer (ACT), immune checkpoint inhibitors, oncolytic viral (OV) therapy, monoclonal antibodies (mAbs), and mRNA-based vaccines. ACT reinfuses enhanced immune cells like tumor-infiltrating lymphocytes (TILs) to combat refractory cancers, while checkpoint inhibitors (eg, PD-1 and CTLA-4 blockers) restore T-cell activity. OV therapy uses engineered viruses (eg, T-VEC) to selectively lyse cancer cells, and advanced mAbs improve targeting precision. mRNA vaccines introduce tumor-specific antigens to trigger robust immune responses. Despite significant progress, challenges like immune-related side effects, high costs, and immunosuppressive tumor microenvironments persist. This review underscores the need for combination strategies and precision medicine to overcome these barriers and maximize the potential of immunotherapy in personalized cancer treatment.

Metastatic brain tumors: from development to cutting-edge treatment

Metastatic brain tumors, also called brain metastasis (BM), represent a challenging complication of advanced tumors. Tumors that commonly metastasize to the brain include lung cancer and breast cancer. In recent years, the prognosis for BM patients has improved, and significant advancements have been made in both clinical and preclinical research. This review focuses on BM originating from lung cancer and breast cancer. We briefly overview the history and epidemiology of BM, as well as the current diagnostic and treatment paradigms. Additionally, we summarize multiomics evidence on the mechanisms of tumor occurrence and development in the era of artificial intelligence and discuss the role of the tumor microenvironment. Preclinically, we introduce the establishment of BM models, detailed molecular mechanisms, and cutting-edge treatment methods. BM is primarily treated with a comprehensive approach, including local treatments such as surgery and radiotherapy. For lung cancer, targeted therapy and immunotherapy have shown efficacy, while in breast cancer, monoclonal antibodies, tyrosine kinase inhibitors, and antibody-drug conjugates are effective in BM. Multiomics approaches assist in clinical diagnosis and treatment, revealing the complex mechanisms of BM. Moreover, preclinical agents often need to cross the blood-brain barrier to achieve high intracranial concentrations, including small-molecule inhibitors, nanoparticles, and peptide drugs. Addressing BM is imperative.

An immune scoring system predicts prognosis and immune characteristics in lung adenocarcinoma brain metastases by RNA sequencing

BACKGROUND

Previous studies have reported that the tumor immune microenvironment (TIME) was associated with the prognosis of lung cancer patients and the efficacy of immunotherapy. However, given the significant challenges in obtaining specimens of brain metastases (BrMs), few studies explored the correlation between the TIME and the prognosis in patients with BrMs from lung adenocarcinoma (LUAD).

METHODS

Transcript profiling of archival formalin-fixed and paraffin-embedded specimens of BrMs from 70 LUAD patients with surgically resected BrMs was carried out using RNA sequencing. An immune scoring system, the green-yellow module score (GYMS), was developed to predict prognosis and immune characteristics in both BrMs and primary LUAD using Weighted Correlation Network analysis (WGCNA) and GSVA analysis. We comprehensively evaluated the immunological role of GYMS based on gene expression profile of LUAD BrMs by systematically correlating GYMS with immunological characteristics and immunotherapy responsiveness in the BrMs. Immunohistochemistry was applied for validation.

RESULTS

We found that the high-GYMS group had better clinical prognosis and inflamed immune landscape including high infiltrations of various immune cells, increased immunomodulatory expression, and enriched immune-related pathways by using RNA-seq and immunohistochemical analysis. Low-GYMS group presented a lacked immune infiltration characteristic. Besides, the high-GYMS group had lower TIDE score and higher T-cell inflamed score than low-GYMS group. The GYMS has been validated in independent BrMs cohorts and primary NSCLC cohort treated with anti-PD-1/PD-L1, showing strong reproducibility and stability in both primary LUAD and BrMs. In addition, we construct a GYMS-related risk signature for patients with LUAD BrMs to predict prognosis.

CONCLUSIONS

We identified two immune-related subtypes which used to estimate prognosis and immune characteristics and developed a reliable GYMS-related risk signature in LUAD BrMs. These results will enhance the understanding of the immune microenvironment in LUAD BrMs and lay the theoretical foundation for the development of personalized therapies for LUAD patients with BrMs.

A viral attack on brain tumors: the potential of oncolytic virus therapy

Managing malignant brain tumors remains a significant therapeutic hurdle that necessitates further research to comprehend their treatment potential fully. Oncolytic viruses (OVs) offer many opportunities for predicting and combating tumors through several mechanisms, with both preclinical and clinical studies demonstrating potential. OV therapy has emerged as a potent and effective method with a dual mechanism. Developing innovative and effective strategies for virus transduction, coupled with immune checkpoint inhibitors or chemotherapy drugs, strengthens this new technique. Furthermore, the discovery and creation of new OVs that can seamlessly integrate gene therapy strategies, such as cytotoxic, anti-angiogenic, and immunostimulatory, are promising advancements. This review presents an overview of the latest advancements in OVs transduction for brain cancer, focusing on the safety and effectiveness of G207, G47Δ, M032, rQNestin34.5v.2, C134, DNX-2401, Ad-TD-nsIL12, NSC-CRAd-S-p7, TG6002, and PVSRIPO. These are evaluated in both preclinical and clinical models of various brain tumors.

PD-L1 inhibitors combined with whole brain radiotherapy in patients with small cell lung cancer brain metastases: Real-world evidence

BACKGROUND

Numerous studies have demonstrated that brain metastases patients may benefit from intracranial radiotherapy combined with immune checkpoint inhibitors (ICIs). However, it is unclear whether this treatment is effective for patients with small cell lung cancer brain metastases (SCLC-BMs).

METHODS

We conducted a retrospective study by analyzing medical records of patients with SCLC-BMs from January 1, 2017 to June 1, 2022. Data related to median overall survival (mOS), median progression-free survival (mPFS), and intracranial progression-free survival (iPFS) were analyzed.

RESULTS

A total of 109 patients were enrolled, of which 60 received WBRT and 49 received WBRT-ICI. Compared to the WBRT alone cohort, the WBRT-ICI cohort showed longer mOS (20.4 months vs. 29.3 months, p = 0.021), mPFS (7.9 months vs. 15.1 months, p < 0.001), and iPFS (8.3 months vs. 16.5 months, p < 0.001). Furthermore, WBRT-ICI cohort had a better response rate for both BMs. (p = 0.035) and extracranial diseases (p < 0.001) compared to those receiving WBRT alone. Notably, the use of WBRT before ICI was associated with longer mOS compared to the use of WBRT after ICI (23.3 months for the ICI-WBRT group vs. 34.8 months for the WBRT-ICI group, p = 0.020).

CONCLUSION

Our results indicated that WBRT combined with immunotherapy improved survival in SCLC-BMs patients compared to WBRT monotherapy. Administering WBRT prior to ICI treatment is associated with improved survival outcomes compared to WBRT following ICI treatment, for patients with SCLC-BMs. These findings highlight the significance of conducting further prospective researches on combination strategies of intracranial radiotherapy and ICI in SCLC-BMs patients.

Combination checkpoint blockade and laser interstitial thermal therapy in radiographically progressive non-small cell lung cancer brain metastases

Background

Laser interstitial thermal therapy (LITT) is a minimally invasive surgical treatment being employed frequently for radiographically progressive brain metastases. Considerable interest exists in combining LITT-mediated in situ vaccination to license immune checkpoint blockade (ICB). No studies have examined the clinical feasibility of this combination in brain metastases.

Methods

All patients receiving LITT for radiographically progressive non-small cell lung carcinoma (NSCLC) brain metastases at a single center from 2015 to 2023 were retrospectively reviewed. Combination therapy was defined as ICB within 6 weeks of LITT. Clinical data, post-LITT freedom from local progression, and overall survival (OS) were collected. Adverse events (AEs) were evaluated according to Common Terminology Criteria.

Results

Eighteen patients received LITT + ICB for a total of 19 lesions. The median time between therapies was 2.29 weeks (range 0.85-5.98). In comparison to NSCLC patients receiving LITT alone or with targeted therapy (LITT only) (n = 25), there was no decrement in procedural outcomes. Patients receiving LITT + ICB discontinued steroids at a median of 11 (4-147) days post-LITT vs. 24 (3-242) days for patients receiving LITT only (P = .62). At study cutoff, the local control rate was 18/19 (94.7%) lesions in the LITT + ICB group and 22/25 (88.0%) in the LITT only group. There were 3 and 5 AEs ≥Grade 3 in the LITT + ICB and LITT-only groups, respectively.

Conclusions

Combination of LITT and ICB does not compromise procedural outcomes or time to steroid discontinuation in NSCLC. Prospective studies are needed to assess biomarkers of immune response.

Real-World Survival of First-Line Immune Checkpoint Inhibitor Treatment Versus Chemotherapy in Older Patients With Non-Small-Cell Lung Cancer and Synchronous Brain Metastases

PURPOSE

This study assessed real-world survival among older patients with non-small-cell lung cancer (NSCLC) and brain metastases (BMs) at diagnosis (synchronous BM [SBM]) receiving first-line immune checkpoint inhibitors (ICIs) compared with chemotherapy only.

METHODS

Patients with NSCLC and SBM age 65 years or older at diagnosis from 2010 to 2019 SEER-Medicare database and received US Food and Drug Administration-approved ICIs (pembrolizumab/nivolumab/ipilimumab/atezolizumab/durvalumab/cemiplimab) and/or chemotherapy (platinum-based doublets/taxane/pemetrexed/gemcitabine) as first-line systemic treatment were included, excluding those with no cranial radiation or ever being treated with targeted therapies. Overall survival time was from the start of systemic treatment (ICI/chemotherapy) to death, censored at disenrollment from Medicare part A/B, enrollment in part C, or end of the study period (December 31, 2019). Kaplan-Meier (KM) survival curves were compared between treatment groups using the log-rank test. Multivariable Cox proportional hazards (CPH) model was used to estimate hazard ratio (HR) between groups, adjusting for patients' sociodemographic and clinical characteristics.

RESULTS

The study included 1,481 patients (1,303 chemotherapy and 178 ICI). The median (range) age was 71 (65-91) years. First-line ICI patients were more likely to be older, live in urban areas, and less likely to be non-White than the chemotherapy group. KM estimates showed that survival curves initially overlapped but diverged approximately 6 months after initiating first-line systemic treatment (median survival [95% CI]: ICI, 190 [131 to 303] days versus chemotherapy, 189 [177 to 201] days), with ICI showing a better survival than the chemotherapy group (log-rank test P < .0001). First-line ICI was associated with a lower risk of death compared with chemotherapy in adjusted CPH model (HR [95% CI], 0.67 [0.55 to 0.80]; P < .0001).

CONCLUSION

Among older patients with NSCLC and SBM, first-line ICI use was associated with improved survival occurring 6 months after treatment initiation compared with chemotherapy only.

Optimal timing and sequence of combining stereotactic radiosurgery with immune checkpoint inhibitors in treating brain metastases: clinical evidence and mechanistic basis

Recent evidence has shown that immune checkpoint inhibitors (ICIs) are efficacious for treating brain metastases of various primary tumors. However, the immunosuppressive tumor microenvironment and the blood-brain barrier (BBB) or blood-tumor barrier (BTB) essentially restrict the efficacy of ICIs. Stereotactic radiosurgery (SRS) can be a powerful ally to ICIs due to its trait of disrupting the BBB/BTB and increasing the immunogenicity of brain metastases. The combination of SRS + ICI has shown synergy in brain metastases in several retrospective studies. Nevertheless, the optimal schedule for the combination of SRS and ICI in brain metastases is yet to be determined. In this review, we summarized the current clinical and preclinical evidence on the timing and sequence of SRS + ICI to provide insight into the current state of knowledge about this important area in patient care.

First-line Immuno-chemotherapy for extensive-stage small-cell lung cancer: A network meta-analysis and cost-effectiveness analysis

Introduction

Many randomized controlled trials have indicated that immuno-chemotherapy could generate clinical benefits, though the cost of immuno-chemotherapy was so prohibitive and the options were varied. This investigation aimed at evaluating effectiveness, safety, and cost-effectiveness for immuno-chemotherapy as a first-line therapeutic option for ES-SCLC patients.

Methods

Multiple scientific literature repositories were searched for clinical studies where immuno-chemotherapy was regarded as the first-line treatment for ES-SCLC, which were published in English between Jan 1, 2000, and Nov 30, 2021. This study conducted a network meta-analysis (NMA) and cost-effectiveness analysis (CEA) based upon US-resident payer perspectives. Overall survival (OS), progression-free survival (PFS), and adverse events (AEs) were evaluated through NMA. In addition, costings, life-years (LYs), quality-adjusted life-years (QALYs), and incremental cost–benefit ratio (ICER) were estimated by CEA.

Results

We identified 200 relevant search records, of which four randomized controlled trials (RCTs) (2,793 patients) were included. NMA demonstrated that the effect of atezolizumab plus chemotherapy was ranked at a more elevated position in comparison to other immuno-chemotherapy options and chemotherapy alone, within the general population. The influence of atezolizumab plus chemotherapy and durvalumab plus chemotherapy was ranked higher within populations experiencing non-brain metastases (NBMs) andbrain metastases (BMs), respectively. The CEA revealed that the ICERs of immuno-chemotherapy over chemotherapyalone were higher than the willingness-to-pay (WTP) threshold of $150,000/QALY in any population. However, treatment with atezolizumab plus chemotherapy and durvalumab plus chemotherapy were more favorable health advantages than other immuno-chemotherapy regimens and chemotherapy alone, and the results were 1.02 QALYs and 0.89 QALYs within overall populations and populations with BMs, respectively.

Conclusion

The NMA and cost-effectiveness investigation demonstrated that atezolizumab plus chemotherapy could be an optimal first-line therapeutic option for ES-SCLC when compared with other immuno-chemotherapy regimens. Durvalumab plus chemotherapy is likely to be the most favorable first-line therapeutic option for ES-SCLC with BMs.

Case report: Brain metastasis necrosis with immune checkpoint inhibitors plus chemotherapy for advanced non-small cell lung cancer

The emergence of immune checkpoint inhibitors (ICIs) has reshaped the landscape of advanced lung cancer treatment. The brain is the most common metastatic site for lung cancer. Whether conventional criteria can evaluate the intracranial response of ICIs remains unclear. Here, we report a well-documented case of intracranial necrosis confirmed by post-operative pathology after only one cycle of chemo-immunotherapy without any radiation therapy, which suggests that immunotherapy elicits strong anti-tumor responses for intracranial metastasis and promotes intracranial necrosis, resulting in a temporary increase in size of the target lesions. Still, the specific mechanisms and management strategies need to be further explored.

Impact of Tumour Segmentation Accuracy on Efficacy of Quantitative MRI Biomarkers of Radiotherapy Outcome in Brain Metastasis

Simple Summary

Radiotherapy is a major treatment option for patients with brain metastasis. However, response to radiotherapy is highly varied among the patients, and it may take months before the response of brain metastasis to radiotherapy is apparent on standard follow-up imaging. This is not desirable, especially given the fact that patients diagnosed with brain metastasis suffer from a short median survival. Recent studies have shown the high potential of machine learning methods for analyzing quantitative imaging features (biomarkers) to predict the response of brain metastasis before or early after radiotherapy. However, these methods require manual delineation of individual tumours on imaging that is tedious and time-consuming, hindering further development and widespread application of these techniques. Here, we investigated the impact of using less accurate but automatically generated tumour outlines on the efficacy of the derived imaging biomarkers for radiotherapy response prediction. Our findings demonstrate that while the effect of tumour delineation accuracy is considerable for automatic contours with low accuracy, imaging biomarkers and prediction models are rather robust to imperfections in the produced tumour masks. The results of this study open the avenue to utilizing automatically generated tumour contours for discovering imaging biomarkers without sacrificing their accuracy.

Abstract

Significantly affecting patients’ clinical course and quality of life, a growing number of cancer cases are diagnosed with brain metastasis (BM) annually. Stereotactic radiotherapy is now a major treatment option for patients with BM. However, it may take months before the local response of BM to stereotactic radiation treatment is apparent on standard follow-up imaging. While machine learning in conjunction with radiomics has shown great promise in predicting the local response of BM before or early after radiotherapy, further development and widespread application of such techniques has been hindered by their dependency on manual tumour delineation. In this study, we explored the impact of using less-accurate automatically generated segmentation masks on the efficacy of radiomic features for radiotherapy outcome prediction in BM. The findings of this study demonstrate that while the effect of tumour delineation accuracy is substantial for segmentation models with lower dice scores (dice score ≤ 0.85), radiomic features and prediction models are rather resilient to imperfections in the produced tumour masks. Specifically, the selected radiomic features (six shared features out of seven) and performance of the prediction model (accuracy of 80% versus 80%, AUC of 0.81 versus 0.78) were fairly similar for the ground-truth and automatically generated segmentation masks, with dice scores close to 0.90. The positive outcome of this work paves the way for adopting high-throughput automatically generated tumour masks for discovering diagnostic and prognostic imaging biomarkers in BM without sacrificing accuracy.

Analysis of Immunotherapy Combined with Radiotherapy in Patients with Brain Metastasis of Driver Gene-Negative Non-Small-Cell Lung Cancer

Purpose. To observe the remission rate and side effects of immunotherapy combined with radiotherapy in patients with brain metastasis of driver gene-negative non-small-cell lung cancer (NSCLC). Methods. 152 patients with NSCLC brain metastasis admitted to our hospital from January 2019 to December 2021 were selected as the research objects. Patients were divided into a single group (85 cases) and a combined group (67 cases) according to treatment methods. The therapeutic effects and side effects of the single group and combined group were compared. In addition, the patients who received immunotherapy combined with radiotherapy were divided into three subgroups: A, B, and C, and the therapeutic effects and side effects of different radiotherapy modes were compared among group A [whole brain radiotherapy (WBRT)], group B (WBRT combined with local radiotherapy) and group C (local radiotherapy). Results. The objective response rate (ORR) and disease control rate (DCR) in the combined group were higher than those in the single group ( $P<0.05$ ). The incidence of reactive capillary hyperplasia and immune-related pneumonia in the combined group were higher than that in the single group ( $P<0.05$ ). There was no significant difference in the incidence of other side effects between the two groups ( $P>0.05$ ). ORR and DCR in group B were higher than those in group A ( $P<0.05$ ). There was no significant difference in the incidence of side effects among the three groups ( $P>0.05$ ). Conclusion. Immunotherapy combined with radiotherapy is effective in patients with brain metastasis of driver gene-negative NSCLC, which can improve the disease control rate without increasing the side effects. In addition, WBRT combined with local push radiotherapy is effective and safe. Clinical Study Registration Number. The Clinical study registration number is K2019086.

Efficacy outcomes and prognostic factors from real-world patients with advanced non-small-cell lung cancer treated with first-line chemoimmunotherapy: The Spinnaker retrospective study

BACKGROUND

Efficacy outcomes and prognostic factors of real-world patients with advanced non-small cell lung cancer (aNSCLC) treated with first-line chemoimmunotherapy are still limited.

PATIENTS AND METHODS

In the retrospective Spinnaker study, data was collected from patients in six United Kingdom and one Swiss oncology centres with first-line pembrolizumab plus platinum-based chemotherapy. Efficacy outcomes and potential prognostic factors were estimated aiming at developing a prognostic model.

RESULTS

Three-hundred-eight patients were included, 32% ≥ 70 years, with ≥ 3 metastatic sites in 33%, brain or liver metastases in 10% and 12%, respectively. With a median follow-up of 18.0 months (mo.) (range, 15.9-20.1), median overall survival (OS) and progression-free survival (PFS) were 12.7 mo. (range, 10.2-15.2), and 8.0 mo. (range, 7.1-8.8), respectively. The neutrophils-to-lymphocytes ratio (NLR) and systemic immune-inflammatory index (SII) (i.e., NLR × platelet count) were both significantly higher in ECOG PS 1 (p = 0.0147 and p = 0.0018, respectively), underweight or normal body mass index (p = 0.0456 and p = 0.0062, respectively), ≥3 metastatic sites (p = 0.0069 and p = 0.112), pretreatment steroids (p = 0.0019 and p = 0.0017). By MVA, the number of metastatic sites ≥ 3 (p < 0.001 and p = 0.002), squamous histology (p = 0.033 and p = 0.013) and SII ≥ 1444 (p = 0.031 and p = 0.009, respectively) were associated with both worse OS and PFS and led to a highly discriminating three-class risk prognostic model.

CONCLUSION

Real-world PFS with chemoimmunotherapy in aNSCLC patients is similar to that reported in clinical trials. A high number of metastatic sites, squamous histology and high SII are adverse prognostic factors that might contribute to a clinically useful prognostic model.

Immune Subtypes in LUAD Identify Novel Tumor Microenvironment Profiles With Prognostic and Therapeutic Implications

The six transcriptomic immune subtypes (ISs) (C1 - C6) were reported to have complex and different interplay between TME and cancer cells in TCGA (The Cancer Genome Atlas) pan-cancer cohort. Our study specifically explored how the consequence of interplay determines the prognosis and the response to therapy in LUAD cohorts. Clinical and molecular information of LUAD patients were from TCGA and Gene Expression Omnibus (GEO). The immune cell populations and gene/pathway enrichment analysis were performed to explore the molecular differences among the C3 IS and other ISs in the LUAD population. The proportion of C3 inflammatory IS was identified as the most common IS in both TCGA (N = 457) and GEO (N = 901) cohorts. The C3 IS was also found to be the most accurate prognostic subtype, which was associated with significantly longer OS (p <0.001) and DFS (p <0.001). The C3 IS presented higher levels of CD8 T, M1 macrophage, and myeloid dendritic cells, while lower levels of M2 macrophages and cancer-associated fibroblast cells. Moreover, the C3 subtype was enriched in the antigen process and presenting, interferon-gamma response, T cell receptor signaling, and natural killer cell-mediated cytotoxicity pathways than C1/C2. In contrast, the C1/C2 presented greater activation of pathways related to the cell cycles, DNA repair, and p53 signaling pathways. The immune-related C3 IS had a great ability to stratify the prognosis of LUAD, providing clues for further pathogenic research. This classification might help direct precision medicine screenings of LUAD patients, thus possibly improving their prognoses.

The Long-Term and Short-Term Efficacy of Immunotherapy in Non-Small Cell Lung Cancer Patients With Brain Metastases: A Systematic Review and Meta-Analysis

BACKGROUND

Although immunotherapy has been widely used, there is currently no research comparing immunotherapy for non-small cell lung cancer (NSCLC) patients with brain metastases (BMs). This meta-analysis addresses a gap in the comparison of immunotherapy efficacy, including immune checkpoint inhibitors (ICIs), chemotherapy (CT), radiotherapy (RT), and ICI combined CT or RT.

METHODS

A search of Pubmed, Cochrane, EMBASE, and ClinicalTrial.gov was conducted to identify studies which enrolled NSCLC patients with BM treated with ICIs. The outcomes consisted of intracerebral overall response rate (iORR), intracerebral disease control rate (iDCR), extracranial overall response rate (EORR), distant brain failure (DBF), local control (LC), progression-free survival (PFS), and overall survival (OS).

RESULTS

A total of 3160 participants from 46 trials were included in the final analysis. Patients treated with immunotherapy were associated with a longer PFS (0.48, 95%CI: 0.41-0.56), and a longer OS (0.64, 95%CI: 0.60-0.69) compared with immunotherapy-naive patients. In prospective studies, dual ICI combined CT and ICI combined CT achieved a better OS. The hazard ratio (HR) of dual ICI combined CT versus dual ICI was 0.61, and the HR of ICI combined CT versus ICI monotherapy was 0.58. Moreover, no statistical difference in PFS, OS, EORR, iORR, iDCR, and EDCR was found between patients with ICI monotherapy and ICI combined cranial radiotherapy. Concurrent ICI combined RT was shown to decrease the rate of DBF (OR = 0.15, 95% CI: 0.03-0.73) compared with RT after ICI. Patients treated with WBRT might have an inferior efficacy than those with SRS because the iORR of SRS was 0.75 (0.70, 0.80) and WBRT was 0. Furthermore, no obvious difference in PFS and OS was observed among the three different types of ICI, which targets PD-1, PD-L1, and CTLA-4, respectively.

CONCLUSIONS

Patients treated with ICI got superior efficacy to those without ICI. Furthermore, dual ICI combined CT and ICI combined CT seemed to be optimal for NSCLC patients with BM. In terms of response and survival, concurrent administration of SRS and ICI led to better outcomes for patients with BMs than non-concurrent or non-SRS.

IMPORTANCE OF THE STUDY

In the new era of immunotherapy, our meta-analysis validated the importance of immunotherapy for non-small cell lung cancer (NSCLC) patients with brain metastases (BMs). By comparing the long-term and short-term impacts of various regimens, all immunotherapy treatments had superior efficacy to immunotherapy-naive. At the same time, through pairwise comparison in immunotherapy, our findings can help clinicians to make treatment decisions for NSCLC patients with BMs.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=269621, identifier CRD42021269621.

Brain metastases, patterns of intracranial progression, and the clinical value of upfront cranial radiotherapy in patients with metastatic non-small cell lung cancer treated with PD-1/PD-L1 inhibitors

BACKGROUND

Despite the emergence of programmed death 1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors in the treatment of non-small cell lung cancer (NSCLC) patients with brain metastases (BMs), knowledge gaps remain regarding the impact and timing of cranial radiotherapy for patients receiving anti-PD-1/PD-L1 therapy.

METHODS

Data were collected from 461 consecutive patients who received anti-PD-1/PD-L1 therapy for metastatic NSCLC at three institutions between June 2017 and September 2020. Intracranial progressive disease (PD) at the original disease sites, new sites, or both sites were classified as original-site PD (OPD), new-site PD (NPD), and original-and-new-site PD (ONPD), respectively. Patients with baseline BMs were categorized based on whether they received upfront cranial radiotherapy (uCRT) at any time point between the introduction of anti-PD-1/PD-L1 therapy and the first subsequent progression.

RESULTS

Of the 461 patients enrolled, 110 (23.9%) had BMs at baseline. The presence of BMs did not show independent prognostic value for progression-free survival (PFS) or overall survival (OS). During a median follow-up of 13.2 months, 96 patients with BMs developed PD, of whom 53 (55.2%) experienced intracranial PD. OPD, NPD, and ONPD were observed in 50.9%, 18.9%, and 30.2% of patients, respectively. Patients who received uCRT exhibited a longer median OS than those with BMs who did not receive uCRT (25.4 vs. 14.6 months, HR: 0.52, 95% CI: 0.29-0.91, P=0.041); this survival advantage was more prominent in patients with 1-4 BMs (median OS, 25.4 vs. 17.0 months, HR: 0.42, 95% CI: 0.22-0.81, P=0.024), and uCRT was independently associated with OS among these patients.

CONCLUSIONS

The presence of BMs at baseline was not associated with poorer OS in patients with metastatic NSCLC treated with anti-PD-1/PD-L1 therapy. Intracranial progression on PD-l/PD-L1 inhibitors predominately occurred at the original BM sites. The use of uCRT may improve OS, especially in NSCLC patients with 1-4 BMs.