Navigate Towards the Immunotherapy Era: Value of Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer Patients With Brain Metastases

Case report: Long-term intracranial effect of zimberelimab monotherapy following surgical resection of high PD-L1-expressing brain metastases from NSCLC

Non-small cell lung cancer (NSCLC) accounted for the majority of lung cancer cases worldwide. Brain metastases (BM) frequently complicate NSCLC and portend a dismal prognosis. To control neurological symptoms, surgical resection is commonly followed by brain radiotherapy (RT). However, RT is often complicated by neurotoxicity. For patients with tumors that harbor positive driver genes, tyrosine kinase inhibitors are considered the standard of care. Nevertheless, treatment options for those without driver gene mutations are still debated. Programmed death receptor 1 (PD-1)/ligand 1 (PD-L1) inhibition has emerged as a novel therapeutic strategy for NSCLC patients with PD-L1-positive tumors, as well as for those with asymptomatic BM. However, the effect of anti-PD-1 antibodies on active BM within such specific populations is undetermined. Herein we present a case of a 65-year-old patient with NSCLC and high PD-L1-expressing BM. The patient underwent surgical resection of BM followed by first-line monotherapy with 31 cycles of zimberelimab, a novel anti-PD-1 antibody, and has already achieved 24 months of progression-free survival and intracranial recurrence-free survival. To our knowledge, this is the first report regarding the intracranial effect of zimberelimab on BM from primary lung cancer. This case report might facilitate an understanding of the intracranial effects of different anti-PD-1 antibodies for such populations.

Coordination of anti-CTLA-4 with whole-brain radiation therapy decreases tumor burden during treatment in a novel syngeneic model of lung cancer brain metastasis

Lung cancer is the most common primary tumor to metastasize to the brain. Although advances in lung cancer therapy have increased rates of survival over the past few decades, control and treatment of lung cancer brain metastasis remains an urgent clinical need. Herein, we examine the temporal coordination of α-CTLA-4 administration in combination with whole-brain radiation therapy in a syngeneic preclinical model of lung cancer brain metastasis in both C57Bl/6 and athymic nude mice. Brain tumor burden, survival, and weight loss were monitored. Immunotherapy administration 24 h prior to irradiation resulted in increased brain tumor burden, while administration of immunotherapy 12 h after radiation decreased tumor burden. Neither of the treatments affected survival outcomes or weight loss due to brain tumor recurrence. These findings suggest that the coordination of α-CTLA-4 administration in addition to whole-brain radiation therapy may be a viable strategy for reduction of tumor burden for the management of lung cancer brain metastasis.

Brain metastases and lung cancer: molecular biology, natural history, prediction of response and efficacy of immunotherapy

Brain metastases stemming from lung cancer represent a common and challenging complication that significantly impacts patients' overall health. The migration of these cancerous cells from lung lesions to the central nervous system is facilitated by diverse molecular changes and a specific environment that supports their affinity for neural tissues. The advent of immunotherapy and its varied combinations in non-small cell lung cancer has notably improved patient survival rates, even in cases involving brain metastases. These therapies exhibit enhanced penetration into the central nervous system compared to traditional chemotherapy. This review outlines the molecular mechanisms underlying the development of brain metastases in lung cancer and explores the efficacy of novel immunotherapy approaches and their combinations.

Choice of radiotherapy modality for the combined treatment of non-small cell lung cancer with brain metastases: whole-brain radiation therapy with simultaneous integrated boost or stereotactic radiosurgery

Purpose

To compare Whole-brain radiation therapy with simultaneous integrated boost (WBRT+SIB) to stereotactic radiosurgery (SRS)for non-small cell lung cancer (NSCLC)with brain metastases (BMs)in terms of overall survival (OS), intracranial progression-free-survival(iPFS), toxicity and objective response rate (ORR).

Methods

A retrospective review was performed in our hospital of 90 patients diagnosed with NSCLC- BM who received either SRS (n = 48) or WBRT+SIB (n = 42) from January 2016 to January 2022. 76 (84.44%) patients received systemic drug therapy after radiotherapy, including chemotherapy(n=53), targeted therapy(n=40), immunotherapy(n=23), and anti-vascular drug therapy(n=45). OS and iPFS were estimated by the Kaplan-Meier method and compared using the log-rank test. Univariate and Multivariate analysis of the prognostic factors was performed using the Cox proportional hazard regression model.

Results

The WBRT+SIB cohort had a longer median iPFS (20.0 versus (VS) 12.0 months, P = 0.0069) and a similar median OS (32.0 vs 28.0 months, P = 0.195) than the SRS cohort. Intracranial objective response rates in WBRT +SIB and SRS cohorts were 76.19% and 70.09%, respectively (P = 0.566). Disease control rates were 88.09% and 83.33%, respectively (P = 0.521). Multivariate analysis showed that WBRT+SIB is the only factor affecting iPFS(hazard ratio (HR):0.597 {95%confidence interval(CI):0.370-0.966}, P=0.035). Sex, Liver metastasis and Lymph node metastasis are risk factors for NSCLC-BM.

Conclusion

In the context of systemic drug therapy, WBRT+SIB may have better intracranial local control than SRS in NSCLC-BM patients.

Advances in the Management of Central Nervous System Metastases in Non-Small Cell Lung Cancer

Central nervous system (CNS) metastases are common among patients with non-small cell lung cancer (NSCLC). While the presence of brain metastases has historically portended poor prognosis, recent advances in local and systemic therapies have greatly improved outcomes for NSCLC patients with CNS involvement. Stereotactic radiology surgery (SRS) has emerged as an effective radiotherapy technique with fewer toxicities compared to whole brain radiotherapy (WBRT). Furthermore, multi-generation tyrosine kinase inhibitors (TKIs) with CNS overall response rates (ORR) of up to 70-80% are now an accepted first-line approach for a subset of advanced NSCLC patients with targetable molecular alterations. In addition, while the CNS was once considered an immunologic sanctuary site, growing evidence shows that immune checkpoint inhibitors (ICIs) can induce durable responses in brain metastases as well. Ongoing efforts to optimize CNS metastases management are necessary to refine multimodal treatment approaches and develop new therapeutics with better CNS penetrance.

Advances in the Molecular Landscape of Lung Cancer Brain Metastasis

Lung cancer is one of the most frequent tumors that metastasize to the brain. Brain metastasis (BM) is common in advanced cases, being the major cause of patient morbidity and mortality. BMs are thought to arise via the seeding of circulating tumor cells into the brain microvasculature. In brain tissue, the interaction with immune cells promotes a microenvironment favorable to the growth of cancer cells. Despite multimodal treatments and advances in systemic therapies, lung cancer patients still have poor prognoses. Therefore, there is an urgent need to identify the molecular drivers of BM and clinically applicable biomarkers in order to improve disease outcomes and patient survival. The goal of this review is to summarize the current state of knowledge on the mechanisms of the metastatic spread of lung cancer to the brain and how the metastatic spread is influenced by the brain microenvironment, and to elucidate the molecular determinants of brain metastasis regarding the role of genomic and transcriptomic changes, including coding and non-coding RNAs. We also present an overview of the current therapeutics and novel treatment strategies for patients diagnosed with BM from NSCLC.

Immunotherapy in NSCLC Patients with Brain Metastases

Approximately 40% of unselected non-small cell lung cancer (NSCLC) patients develop brain metastases (BMs) during their disease, with considerable morbidity and mortality. The management of BMs in patients with NSCLC is a clinical challenge and requires a multidisciplinary approach to gain effective intracranial disease control. Over the last decade, immune checkpoint inhibitors (ICIs) have emerged as a game-changer in the treatment landscape of advanced NSCLC, with significant improvements in survival outcomes, although patients with BMs are mostly underrepresented in randomized clinical trials. Moreover, the safety and activity of ICIs and radiotherapy combinations compared with single-agent or sequential modalities is still under evaluation to establish the optimal management of these patients. The aim of this review is to summarize the state-of-the-art of clinical evidence of ICIs intracranial activity and the main challenges of incorporating these agents in the treatment armamentarium of NSCLC patients with BMs.