PD-1/PD-L1 Inhibitor Combined with Chemotherapy Can Improve the Survival of Non-Small Cell Lung Cancer Patients with Brain Metastases

The safety and efficacy of anti-PD-1/PD-L1 monoclonal antibodies for lung cancer brain metastasis: a systematic review and meta-analysis on brain metastasis

Individuals with non-small cell lung cancer (NSCLC) who develop brain metastases face a poor prognosis and limited treatment options. Programmed cell death protein 1 (PD-1) inhibitors, such as pembrolizumab and nivolumab, have emerged as a promising immunotherapy for treating lung cancer with brain metastases. This systematic review and meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline and evaluate the safety and efficacy of anti-PD-1/PD-L1 monoclonal antibodies in treating lung cancer patients with brain metastases. A comprehensive literature search was conducted to identify relevant studies up to 27 August 2023. Data on overall survival (OS), progression-free survival, radiological response rates, and adverse events were extracted. All statistical analysis was performed using STATA v.17. Our literature search yielded 39 eligible studies involving 15,428 patients. The overall response rate for PD-1 inhibitors was substantial, with pooled rates of 39% for overall response, 7% for complete response (CR), 27% for partial response (PR), and 31% for stable disease (SD). The pooled 6-month OS rate was 77%, and the 1-year OS rate was 61%. Subgroup analyses revealed higher PD-L1 expression levels and the use of platinum-based chemotherapy alongside immunotherapy were associated with improved outcomes. PD-1/PD-L1 inhibitors have demonstrated promising efficacy and safety in treating lung cancer patients with brain metastases, as evidenced by significant improvements in OS, PFS, and response rates. Incorporating PD-1/PD-L1 inhibitors into the treatment regimen, particularly for patients with high PD-L1 expression, has the potential to improve clinical outcomes in this patient population.

Evaluation of the effectiveness and safety of combining PD-1/PD-L1 inhibitors with anti-angiogenic agents in unresectable hepatocellular carcinoma: a systematic review and meta-analysis

BACKGROUND

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality globally, particularly when diagnosed at an unresectable stage. Traditional treatments for advanced HCC have limited efficacy, prompting the exploration of combination therapies. This systematic review and meta-analysis evaluate the effectiveness and safety of combining PD-1/PD-L1 inhibitors with anti-angiogenic agents in patients with unresectable HCC.

METHODS

A comprehensive literature search was conducted in PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science, including studies up to June 2024. Randomized controlled trials (RCTs) comparing combination therapy (PD-1/PD-L1 inhibitors with anti-angiogenic agents) to monotherapy or standard treatments in unresectable HCC patients were included. Data were synthesized using random-effects models, with pooled hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS), and risk ratios (RRs) for objective response rate (ORR) and adverse events (AEs).

RESULTS

Five Phase III RCTs involving 1515 patients were included. Combination therapy significantly improved OS (HR: 0.71, 95% CI: 0.60-0.85) and PFS (HR: 0.64, 95% CI: 0.53-0.77) compared to monotherapy or standard treatments. The pooled OR for ORR was 1.27 (95% CI: 1.57-2.11), indicating a higher response rate with combination therapy. However, the risk of AEs was also higher in the combination therapy group (RR: 1.04, 95% CI: 1.02-1.06). Subgroup analyses revealed consistent benefits across different types of PD-1/PD-L1 inhibitors and anti-angiogenic agents, with no significant publication bias detected.

CONCLUSIONS

The combination of PD-1/PD-L1 inhibitors with anti-angiogenic agents offers significant benefits in improving OS and PFS in patients with unresectable HCC, although it is associated with an increased risk of adverse events.

Efficacy of different therapies for brain metastases of non-small cell lung cancer: a systematic review and meta-analysis

Background

As one of the most common causes of death in advanced non-small cell lung cancer (NSCLC), brain metastases (BM) have attracted attention and debate about treatment options, especially for patients with negative driver genes or resistance to targeted agents. Therefore, we conducted a meta-analysis to investigate the potential benefit of different therapeutic regimens for intracranial lesions in non-targeted therapy NSCLC patients.

Methods

A comprehensive search was conducted in databases including PubMed, Embase, and the Cochrane Library. The primary endpoints included the intracerebral objective response rate (icORR) and intracerebral progression-free survival (iPFS) in patients with BM.

Results

Thirty-six studies involving 1,774 NSCLC patients with baseline BM were included in this meta-analysis. Antitumor agents plus radiotherapy (RT) showed the most significant synergistic effects; the highest pooled icORR that appeared in the combination of immune checkpoint inhibitor (ICI) and RT was 81% [95% confidence interval (CI): 16-100%], and the median iPFS was 7.04 months (95% CI: 2.54-11.55 months). The pooled icORR and median iPFS of RT plus chemotherapy were 46% (95% CI: 34-57%) and 5.7 months (95% CI: 3.90-7.50 months), respectively. The highest median iPFS in nivolumab plus ipilimumab plus chemotherapy was 13.5 months (95% CI: 8.35-18.65 months). ICI plus chemotherapy also showed potent antitumor activity in BM, with a pooled icORR of 56% (95% CI: 29-82%) and a median iPFS of 6.9 months (95% CI: 3.20-10.60 months). Notably, the subgroup analysis indicated that the pooled icORR of patients in programmed cell death-ligand 1 (PD-L1) (≥50%) who received ICI was 54% (95% CI: 30-77%), and that of patients who received first-line ICI was 69.0% (95% CI: 51-85%).

Conclusions

ICI-based combination treatment provides a long-term survival benefit for non-targeted therapy patients, with the most significant benefits observed in improving icORR and prolonging overall survival (OS) and iPFS. In particular, patients who received first-line treatment or who were PD-L1-positive had a more significant survival benefit from aggressive ICI-based therapies. For patients with a PD-L1-negative status, chemotherapy plus RT led to better clinical outcomes than other treatment regimens. These innovative findings could help clinicians to better select therapeutic strategies for NSCLC patients with BM.

Immune checkpoint inhibitors for the treatment of non-small cell lung cancer brain metastases

ABSTRACT

Lung cancer has the highest risk of brain metastasis (BM) among all solid carcinomas. The emergence of BM has a significant impact on the selection of oncologic treatment for patients. Immune checkpoint inhibitors (ICIs) are the most promising treatment option for patients without druggable mutations and have been shown to improve survival in patients with non-small cell lung cancer (NSCLC) BM in clinical trials with good safety. Moreover, ICI has shown certain effects in NSCLC BM, and the overall intracranial efficacy is comparable to extracranial efficacy. However, a proportion of patients showed discordant responses in primary and metastatic lesions, suggesting that multiple mechanisms may exist underlying ICI activity in BM. According to studies pertaining to tumor immune microenvironments, ICIs may be capable of provoking immunity in situ. Meanwhile, systematic immune cells activated by ICIs can migrate into the central nervous system and exert antitumor effects. This review summarizes the present evidence for ICI treatment efficacy in NSCLC BM and proposes the possible mechanisms of ICI treatment for NSCLC BMs based on existing evidence.

Efficacy of PD-1/PD-L1 Inhibitors versus Chemotherapy in Lung Cancer with Brain Metastases: A Systematic Review and Meta-Analysis

Immune checkpoint inhibitors (ICIs) are widely used to treat local or metastatic lung cancer. However, the efficacy of ICI in patients with brain metastases (BM) from lung cancer is unknown. This study aimed to evaluate the efficacy of PD-1/PD-L1 ICIs compared with chemotherapy for patients with lung cancer with BM. Electronic databases (PubMed, Embase, The Cochrane Library, and Web of Science) were searched. The meta-analysis assessed overall survival (OS) and progression-free survival (PFS) of the PD-1/PD-L1 inhibitors axis and its relationship with pathological type, drug modality, and the treatment line number in patients with BM from lung cancer. We included 694 patients with BM from lung cancer from 11 randomized controlled trials. Statistical analysis showed that compared with chemotherapy, PD-1/PD-L1 inhibitors could significantly prolong OS (hazard ratio (HR) = 0.75, 95%confidence interval (95%CI) = 0.51–0.99) and PFS (HR = 0.65, 95%CI = 0.51–0.80). In the subgroup analysis, ICIs plus chemotherapy improved PFS (HR = 0.60, 95%CI = 0.40–0.80), but not OS (HR = 0.75, 95%CI = 0.30–1.19). The efficacy of ICI monotherapy in patients with BM was significantly different between OS and PFS: OS pooled HR = 0.81 (95%CI = 0.57–1.05) and PFS = 0.78 (95%CI = 0.62–0.94). Among different pathological types, the OS pooled HR was 0.67 (95%CI = 0.39–0.95) for non-small cell lung cancer (NSCLC) and 0.94 (95%CI = 0.56–1.33) for small cell lung cancer (SCLC); the PFS pooled HR was 0.58 (95%CI = 0.39–0.76) for NSCLC and 0.79 (95%CI = 0.65–0.93) for SCLC. Subgroups analysis of treatment line showed that no advantage for OS with ICIs as first-line or subsequent-line therapy, whereas ICIs as first-line (HR = 0.63, 95%CI = 0.53–0.74) and second-line (HR = 0.62, 95%CI = 0.62–0.96) benefitted PFS. This meta-analysis implied that compared with chemotherapy, PD-1/PD-L1 inhibitors significantly improved efficacy treatment of patients with BM from lung cancer. Further studies are needed to confirm the role of ICIs in different pathological types and drug treatment modalities.

Tumor Immune Microenvironment and Immunotherapy in Brain Metastasis From Non-Small Cell Lung Cancer

Brain metastasis (BM), a devastating complication of advanced malignancy, has a high incidence in non-small cell lung cancer (NSCLC). As novel systemic treatment drugs and improved, more sensitive imaging investigations are performed, more patients will be diagnosed with BM. However, the main treatment methods face a high risk of complications at present. Therefore, based on immunotherapy of tumor immune microenvironment has been proposed. The development of NSCLC and its BM is closely related to the tumor microenvironment, the surrounding microenvironment where tumor cells live. In the event of BM, the metastatic tumor microenvironment in BM is composed of extracellular matrix, tissue-resident cells that change with tumor colonization and blood-derived immune cells. Immune-related cells and chemicals in the NSCLC brain metastasis microenvironment are targeted by BM immunotherapy, with immune checkpoint inhibition therapy being the most important. Blocking cancer immunosuppression by targeting immune checkpoints provides a suitable strategy for immunotherapy in patients with advanced cancers. In the past few years, several therapeutic advances in immunotherapy have changed the outlook for the treatment of BM from NSCLC. According to emerging evidence, immunotherapy plays an essential role in treating BM, with a more significant safety profile than others. This article discusses recent advances in the biology of BM from NSCLC, reviews novel mechanisms in diverse tumor metastatic stages, and emphasizes the role of the tumor immune microenvironment in metastasis. In addition, clinical advances in immunotherapy for this disease are mentioned.

Efficacy of PD-1/PD-L1 inhibitors in patients with non-small cell lung cancer and brain metastases: A real-world retrospective study in China

BACKGROUND

There is only limited knowledge of the treatment responses and clinical outcomes of immune checkpoint inhibitors (ICIs) in driver gene-negative non-small cell lung cancer (NSCLC) patients with brain metastases (BM). This study aims to assess the efficacy of immunotherapy in these patients in a real world setting.

METHODS

NSCLC-BM patients without driver gene mutations who received ICIs were retrospectively identified between July 2017 and December 2019. The primary observation endpoint was intracranial objective response rate (iORR), and secondary objectives were objective response rate (ORR), intracranial and systemic progression-free survival (iPFS, PFS), and overall survival (OS).

RESULTS

We reviewed 1578 patients with lung cancer and BM. According to the exclusion criteria, 41 patients were finally enrolled. Among these 41 patients, iORR was 36.6% (95% confidence interval [CI] = 21.2%-52.0%), whereas iPFS was 6.8 (95% CI = 3.32-10.35) months. Additionally, ORR, PFS, and OS were 24.4% (95% CI = 10.7%-38.1%), 6.2 (95% CI = 4.57-7.83) months and 13.7 (95% CI = 11.20-16.26) months, respectively. ICIs combined with concurrent radiotherapy group exhibited preferred iORR (p = 0.030) compared with no radiotherapy group, and ICIs plus chemotherapy showed improved OS (p = 0.024) compared to ICI monotherapy. Moreover, the lines of ICI treatment ≥2 (p = 0.005) and derived neutrophil-to-lymphocyte ratio (dNLR) ≥3 (p = 0.010) were independently negative factors for OS.

CONCLUSION

In NSCLC-BMs patients lacking driver genes, ICIs exhibited an effective drug regime. A combination of ICIs with concurrent radiotherapy showed a better intracranial response, whereas ICIs plus chemotherapy were associated with superior OS.