The risk factors for brain metastases in patients with non-small cell lung cancer

Assessing survival in non-small cell lung cancer brain metastases after stereotactic radiosurgery: before and after the start of the targetable mutation era

PURPOSE

Targeted treatment options for non-small cell lung cancer (NSCLC) brain metastases (BMs) may be combined with stereotactic radiosurgery (SRS) to optimize survival. We assessed patient outcomes after SRS for NSCLC BMs, identifying survival trajectories associated with targetable mutations.

METHODS

In this retrospective time-dependent analysis, we analyzed median overall survival of patients who received ≥ 1 SRS courses for BM from NSCLC from 2001 to 2021. We compared survival of patients with and without targetable mutations based on clinical variables and treatment.

RESULTS

Among the 213 patients included, 87 (40.8%) had targetable mutations-primarily EGFR (22.5%)-and 126 (59.2%) did not. Patients with targetable mutations were more often female (63.2%, p <.001) and nonsmokers (58.6%, p <.001); had higher initial lung-molGPA (2.0 vs. 1.5, p <.001) and lower cumulative tumor volume (3.7 vs. 10.6 cm3, p <.001); and received more concurrent (55.2% vs. 36.5%, p =.007) and total (median 3 vs. 2, p <.001) systemic therapies. These patients had lower mortality rates (74.7% vs. 91.3%, p <.001) and risk (HR 0.298 [95%CI 0.190-0.469], p <.001) and longer median overall survival (20.2 vs. 7.4 months, p <.001), including survival ≥ 3 years (p =.001). Survival was best predicted by SRS with tumor resection in patients with non-targetable mutations (HR 0.491 [95%CI 0.318-757], p =.001) and by systemic therapy with SRS for those with targetable mutations (HR 0.124 [95%CI 0.013-1.153], p =.067).

CONCLUSION

The presence of targetable mutations enhances survival in patients receiving SRS for NSCLC BM, particularly when used with systemic therapies. Survival for patients without targetable mutations was longest with SRS and surgical resection. These results inform best practices for managing patients with NSCLC BM based on driver mutation status.

Clinical Management of Patients with Non-Small Cell Lung Cancer, Brain Metastases, and Actionable Genomic Alterations: A Systematic Literature Review

INTRODUCTION

Nearly 60% of patients with non-small cell lung cancer (NSCLC) present with metastatic disease, and approximately 20% have brain metastases (BrMs) at diagnosis. During the disease course, 25-50% of patients will develop BrMs. Despite available treatments, survival rates for patients with NSCLC and BrMs remain low, and their overall prognosis is poor. Even with newer agents for NSCLC, options for treating BrMs can be limited by their ineffective transport across the blood-brain barrier (BBB) and the unique brain tumor microenvironment. The presence of actionable genomic alterations (AGAs) is a key determinant of optimal treatment selection, which aims to maximize responses and minimize toxicities. The objective of this systematic literature review (SLR) was to understand the current landscape of the clinical management of patients with NSCLC and BrMs, particularly those with AGAs.

METHOD

A Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA)-compliant SLR was conducted to identify studies in patients with BrMs in NSCLC. Searches used the EMBASE and MEDLINE® databases, and articles published between January 1, 2017 and September 26, 2022 were reviewed.

RESULTS

Overall, 179 studies were included in the SLR. This subset review focused on 80 studies that included patients with NSCLC, BrMs, and AGAs (19 randomized controlled trials [RCTs], two single-arm studies, and 59 observational studies). Sixty-four of the 80 studies reported on epidermal growth factor receptor (EGFR) mutations, 14 on anaplastic lymphoma kinase (ALK) alterations, and two on both alterations. Ninety-five percent of studies evaluated targeted therapy. All RCTs allowed patients with previously treated, asymptomatic, or neurologically stable BrMs; the percentage of asymptomatic BrMs varied across observational studies.

CONCLUSIONS

Although targeted therapies demonstrate systemic benefits for patients with NSCLC, BrMs, and AGAs, there remains a continued need for effective therapies to treat and prevent BrMs in this population. Increased BBB permeability of emerging therapies may improve outcomes for this population.

Survival Predictive Nomograms for Non-Surgical Brain Metastases Patients From Non-Small Cell Lung Cancer Receiving Radiotherapy: A Population-Based Study

OBJECTIVE

A high number of Non-Small Cell Lung Cancer (NSCLC) patients with brain metastasis who have not had surgery often have a negative outlook. Radiotherapy remains a most common and effective method. Nomograms were developed to forecast the cancer-specific survival (CSS) and overall survival (OS) in NSCLC individuals with nonoperative brain metastases who underwent radiotherapy.

METHODS

Information was gathered from the Surveillance, Epidemiology, and End Results (SEER) database about patients diagnosed with NSCLC who had brain metastases not suitable for surgery. Nomograms were created and tested using multivariate Cox regression models to forecast CSS and OS at intervals of 1, 2, and 3 years.

RESULTS

The research involved 3413 individuals diagnosed with NSCLC brain metastases who had undergone radiotherapy but had not experienced surgery. These participants were randomly divided into two categories. The analysis revealed that gender, age, ethnicity, marital status, tumor location, tumor laterality, tumor grade, histology, T stage, N stage, chemotherapy, tumor size, lung metastasis, bone metastasis, and liver metastasis were significant independent predictors for OS and CSS. The C-index for the training set for predicting OS was .709 (95% CI, .697-.721), and for the validation set, it was .705 (95% CI, .686-.723), respectively. The C-index for predicting CSS was .710 (95% CI, .697-.722) in the training set and .703 (95% CI, .684-.722) in the validation set, respectively. The nomograms model, as suggested by the impressive C-index, exhibits outstanding differentiation ability. Moreover, the ROC and calibration curves reveal its commendable precision and distinguishing potential.

CONCLUSIONS

For the first time, highly accurate and reliable nomograms were developed to predict OS and CSS in NSCLC patients with non-surgical brain metastases, who have undergone radiotherapy treatment. The nomograms may assist in tailoring counseling strategies and choosing the most effective treatment method.

Interim survival analysis of the randomized phase III GEMSTONE-302 trial: sugemalimab or placebo plus chemotherapy as first-line treatment for metastatic NSCLC

The randomized, double-blinded, multi-center, phase III GEMSTONE-302 ( NCT03789604 ) study evaluated the efficacy and safety of sugemalimab versus placebo in combination with chemotherapy as first-line treatment for metastatic non-small-cell lung cancer (NSCLC). In this study, 479 treatment-naive patients with stage IV squamous or non-squamous NSCLC without known EGFR sensitizing mutations, ALK, ROS1 or RET fusions were randomized (2:1) to receive 1,200 mg of sugemalimab (n = 320) or placebo (n = 159) every 3 weeks in combination with platinum-based chemotherapy for up to four cycles, followed by maintenance therapy with sugemalimab or placebo for squamous NSCLC and sugemalimab or placebo plus pemetrexed for non-squamous NSCLC. Placebo-treated patients could cross over to receive sugemalimab monotherapy on disease progression. The primary endpoint was investigator-assessed progression-free survival (PFS) and the secondary endpoints included overall survival (OS) and objective response rate. Sugemalimab plus chemotherapy has demonstrated significant PFS prolongation in the primary analysis as reported previously. As of 22 November 2021, the prespecified interim OS analysis showed significant improvement with the addition of sugemalimab to chemotherapy (median OS = 25.4 versus 16.9 months; hazard ratio = 0.65; 95% confidence interval = 0.50-0.84; P = 0.0008). Sugemalimab plus chemotherapy provided superior PFS and OS compared to placebo plus chemotherapy, supporting the use of sugemalimab as a first-line treatment option for metastatic NSCLC.

Brain Metastasis Incidence and Patterns of Presentation After Definitive Treatment of Locally Advanced Non-Small Cell Lung Cancer: A Potential Argument for Brain Magnetic Resonance Imaging Surveillance

Purpose

Brain metastases (BMs) are a common source of morbidity and mortality. Guidelines do not advise brain surveillance for locally advanced non-small cell lung cancer (LA-NSCLC). We describe the incidence, time to development, presentation, and management of BMs after definitive chemoradiotherapy (CRT).

Methods and Materials

We reviewed records of patients with LA-NSCLC treated with CRT within the period from 2013 to 2020. Descriptive statistics were used to characterize the population and the Kaplan-Meier method was used to estimate time to BM. Fisher exact tests and Wilcoxon rank-sum tests were used to compare outcomes between symptomatic and asymptomatic patients.

Results

A total of 219 patients were reviewed including 96 with squamous cell carcinoma, 88 with adenocarcinoma, and 35 with large cell/not otherwise specified (LC/NOS). Thirty-nine patients (17.8%) developed BMs: 35 (90%) symptomatic and 4 (10%) asymptomatic. The rate of BM was highest in LC/NOS (34.3%) and adenocarcinoma (23.9%). Ninety percent of BMs occurred within 2 years. All asymptomatic patients underwent stereotactic radiosurgery alone, compared with 40% of symptomatic patients (P = .04). Symptomatic patients were more likely to require hospitalization (65.7% vs 0%, P = .02), craniotomy (25.7% vs 0%, not significant), and steroids (91.4% vs 0%, P < .001). Cumulative BM volume was higher for symptomatic patients (4 vs 0.24 cm³, P < .001) as was median greatest axial dimension (2.18 vs 0.52 cm, P < .001).

Conclusions

We identified a high rate of BMs, particularly in LC/NOS and adenocarcinoma histology NSCLC. The majority were symptomatic. These results provide rationale for post-CRT magnetic resonance imaging brain surveillance for patients at high risk of BM.

Imaging of brain metastasis in non-small-cell lung cancer: indications, protocols, diagnosis, post-therapy imaging, and implications regarding management

Increased survival (due to the use of targeted therapies based on genomic profiling) has resulted in the increased incidence of brain metastasis during the course of disease, and thus, made it essential to have proper imaging guidelines in place for brain metastasis from non-small-cell lung cancer (NSCLC). Brain parenchymal metastases can have varied imaging appearances, and it is pertinent to be aware of the various molecular risk factors for brain metastasis from NSCLC along with their suggestive imaging appearances, so as to identify them early. Leptomeningeal metastasis requires additional imaging of the spine and an early cerebrospinal fluid (CSF) analysis. Differentiation of post-therapy change from recurrence on imaging has a bearing on the management, hence the need for its awareness. This article will provide in-depth literature review of the epidemiology, aetiopathogenesis, screening, detection, diagnosis, post-therapy imaging, and implications regarding the management of brain metastasis from NSCLC. In addition, we will also briefly highlight the role of artificial intelligence (AI) in brain metastasis screening.

Brain parenchymal and leptomeningeal metastasis in non-small cell lung cancer

Patients with advanced non-small cell lung cancer (NSCLC) are prone to brain metastases (BM), which essentially include brain parenchymal metastases (PM) and leptomeningeal metastases (LM). We conducted a retrospective study to comprehensively assess the clinical characteristics and risk factors of patients with advanced NSCLC who develop PM and LM. Patients with advanced NSCLC were enrolled. These patients were then divided into three groups for analysis: patients without BM (No-BM), patients with PM and patients with LM. Data on clinical characteristics of each patient at the time of diagnosis advanced NSCLC were extracted and analyzed. In addition, prediction models were developed and evaluated for PM and LM. A total of 592 patients were enrolled in the study. BM was present in 287 patients (48.5%). Among them, 185 and 102 patients had PM or LM. Patients with LM had a higher proportion of EGFR exon 21point mutations (L858R) compared to patients with No-BM and PM (p < 0.0001). The median time to the onset of PM and LM from the diagnosis of advanced NSCLC was 0 months and 8.3 months, respectively. Patients with LM had a statistically shorter over survival (OS) compared to either No-BM or PM patients (p < 0.0001). Based on independent predictive variables, two nomogram models were constructed to predict the development of PM and LM in advanced NSCLC patients, and the C-indexes were 0.656 and 0.767, respectively. Although both considered as BM, PM and LM had different clinical characteristics. And the nomogram showed good performance in predicting LM development, but not PM.

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.

Adult brain tumors in Sub-Saharan Africa: A scoping review

BACKGROUND

Sub-Saharan African (SSA) neuro-oncologists report high workloads and challenges in delivering evidence-based care; however, these reports contrast with modeled estimates of adult neuro-oncology disease burden in the region. This scoping review aimed to better understand the reasons for this discrepancy by mapping out the SSA adult brain tumor landscape based on published literature.

METHODS

Systematic searches were conducted in OVID Medline, Global Index Medicus, African Journals Online, Google Scholar, and faculty of medicine libraries from database inception to May 31 st, 2021. The results were summarized quantitatively and narratively. English and French peer-reviewed articles were included (title, abstract, and full text).

RESULTS

Of the 819 records identified, 119 articles by 24 SSA countries (42.9%) were included in the final review. Odeku published the first article in 1967, and nine of the ten most prolific years were in the 21 st century. The greatest contributing region was Western Africa (n=58, 48.7%) led by Nigeria (n=37, 31.1%). Central Africa had fewer articles published later than the other SSA regions (p=0.61). Most studies were non-randomized (n=75, 63.0%) and meningiomas (n=50, 42.0%) were the most common brain tumors reported. Less than 30 studies reported on adjuvant treatment or patient outcomes.

CONCLUSIONS

Most publications were hospital-based, and there was significant heterogeneity in the quality of evidence and reporting. This study highlights the need for rapid and sustainable investments and brain tumor research capacity in SSA.

Association between PD-L1 expression and initial brain metastasis in patients with non-small cell lung cancer and its clinical implications

Background

Brain metastases frequently occur in patients with non‐small cell lung cancer (NSCLC) resulting in a poor prognosis. Here, we investigated the association between PD‐L1 expression and brain metastasis in patients with NSCLC and its clinical significance.

Methods

A total of 270 patients diagnosed with metastatic NSCLC who underwent PD‐L1 testing on their tumor tissue between January 2017 and March 2019 were retrospectively reviewed. The VENTANA PD‐L1 (SP263) assay was used, and positive PD‐L1 expression was defined as staining in ≥1% of tumor cells.

Results

Positive PD‐L1 expression was observed in 181 (67.0%) patients, and 74 (27.4%) patients had brain metastasis at diagnosis. Synchronous brain metastases were more frequently observed in PD‐L1‐positive compared with PD‐L1‐negative patients (31.5% vs. 19.1%, p = 0.045). Multiple logistic regression analysis identified positive PD‐L1 expression (odds ratio [OR]: 2.24, p = 0.012) as an independent factor associated with synchronous brain metastasis, along with the histological subtype of nonsquamous cell carcinoma (OR: 2.84, p = 0.003). However, the incidence of central nervous system (CNS) progression was not associated with PD‐L1 positivity, with a two‐year cumulative CNS progression rate of 26.3% and 28.4% in PD‐L1‐positive and PD‐L1‐negative patients, respectively (log rank p = 0.944). Furthermore, positive PD‐L1 expression did not affect CNS progression or overall survival in patients with synchronous brain metastasis (long rank p = 0.513 and 0.592, respectively).

Conclusions

Initial brain metastases are common in NSCLC patients with positive PD‐L1 expression. Further studies are necessary to understand the relationship between early brain metastasis and cancer immunity.

The construction and validation of the model for predicting the incidence and prognosis of brain metastasis in lung cancer patients

BACKGROUND

Brain metastasis (BM) causes high morbidity and mortality rates in lung cancer (LC) patients. The present study aims to develop models for predicting the development and prognosis of BM using a large LC cohort.

METHODS

A total of 266,522 LC cases diagnosed between 2010 and 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) Program cohort. Risk factors for developing BM and prognosis were calculated by univariable and multivariable logistic and Cox regression analysis, respectively, and nomograms were constructed based on risk factors. Nomogram performance was evaluated with receiver operating characteristics (ROC) curve, or C-index and calibration curve.

RESULTS

The prevalence of BM was 13.33%. Associated factors for developing BM include: advanced age; Asian or Pacific Islander race; uninsured status; primary tumor site; higher T stage; higher N stage; poorly differentiated grade; the presence of lung, liver, and bone metastases; and adenocarcinoma histology. Median overall survival (OS) was 4 months; associated prognosis factors were similar to risk factors plus female gender, unmarried status, and surgery. The calibration curve showed good agreement between predicted and actual probability, and the AUC/C-index was 73.1% (95% CI: 72.6-73.6%) and 0.88 (95% CI: 0.87-0.89) for risk and prognosis predictive models, respectively.

CONCLUSIONS

BM was highly developed in LC patients, and homogeneous and heterogeneous factors were found between risk and prognosis for BM. The nomogram showed good performance in predicting BM development and prognosis.

Response of Pembrolizumab Alone for Non-small Cell Lung Cancer With Brain Metastasis: A Case Report and Literature Review

Treatment of brain metastases often includes surgical resection, chemotherapeutics and radiotherapy. Given the difficulty in obtaining therapeutic levels of medications within the immune-privileged central nervous system, chemotherapy as a stand-alone treatment modality for brain metastases is an uncommon option. However, there is a growing body of evidence to suggest that immunomodulatory agents can induce a robust immune response in the central nervous system. Here, we describe a 68-year old male who presented with radiographic evidence of new and enlarging lung nodules with mediastinal adenopathy. Lung biopsy was consistent with adenocarcinoma. Immunohistochemical staining demonstrated high expression of programmed cell death protein 1 with a tumor proportion score of 100%. Surveillance magnetic resonance imaging of the brain demonstrated a single enhancing 11 × 7 × 12 mm lesion along the mesial surface of the right frontal lobe. The patient deferred surgical resection as well as stereotactic radiosurgery but agreed to treatment with pembrolizumab. Repeat magnetic resonance imaging at 3-months after initiation of treatment demonstrated complete radiographic resolution of the brain lesion. To our knowledge, this is one of only a few reports in the current literature to document complete resolution of non-small cell lung cancer brain metastasis with pembrolizumab alone. We discuss the emerging literature regarding the efficacy of pembrolizumab in the treatment of brain metastases, central nervous system penetration, and emerging new treatment paradigms involving novel immunotherapy agents.