Cell Lung Cancer Brain Metastases Research Articles

Hypofractionated stereotactic radiotherapy for brain metastases in lung cancer patients: dose‒response effect and toxicity

BackgroundLung cancer is a common cause of brain metastases, approximately 40% of patients with lung cancer will develop brain metastases at some point during their disease. Hypofractionated stereotactic radiotherapy (HSRT) has been demonstrated to be effective in controlling limited brain metastases. However, there is still no conclusive on the optimal segmentation of HSRT. The aim of our study was to explore the correlation between the HSRT dosage and its treatment effect and toxicity.MethodsA retrospective analysis was conducted on patients with non-small cell lung cancer (NSCLC) brain metastasis at Hangzhou Cancer Hospital from 1 January 2019 to 1 January 2021. The number of brain metastases did not exceed 10 in all patients and the number of fractions of HSRT was 5. The prescription dose ranges from 25 to 40 Gy. The Kaplan–Meier method was used for estimation of the localised intracranial control rate (iLC). Adverse radiation effects (AREs) were evaluated according to CTCAE 5.0. This study was approved by the Institutional Ethics Review Board of the Hangzhou Cancer Hospital (#73/HZCH-2022).ResultsForty eligible patients with a total of 70 brain metastases were included in this study. The 1-year iLC was 76% and 89% in the prescribed dose ≤ 30 Gy and > 30 Gy group, respectively (P < 0.05). For patients treated with HSRT combined with targeted therapy, immunotherapy and chemotherapy, the 1-year iLC was 89%, 100%, and 45%, respectively. No significant associations were observed between the number, maximum diameter, location, and type of pathology of brain metastases. The rate of all-grade AREs was 33%. Two patients who received a total dose of 40 Gy developed grade 3 headache, the rest of the AREs were grade 1–2.ConclusionsIncreasing the prescription dose of HSRT improves treatment effect but may also exacerbate the side effects. Systemic therapy might impact the iLC rate, and individualized treatment regimens need to be developed.

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

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. 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. 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). 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.

A Review of the Molecular Determinants of Therapeutic Response in Non-Small Cell Lung Cancer Brain Metastases.

Lung cancer is a leading cause of cancer-related morbidity and mortality worldwide. Metastases in the brain are a common hallmark of advanced stages of the disease, contributing to a dismal prognosis. Lung cancer can be broadly classified as either small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC). NSCLC represents the most predominant histology subtype of lung cancer, accounting for the majority of lung cancer cases. Recent advances in molecular genetics, coupled with innovations in small molecule drug discovery strategies, have facilitated both the molecular classification and precision targeting of NSCLC based on oncogenic driver mutations. Furthermore, these precision-based strategies have demonstrable efficacy across the blood-brain barrier, leading to positive outcomes in patients with brain metastases. This review provides an overview of the clinical features of lung cancer brain metastases, as well as the molecular mechanisms that drive NSCLC oncogenesis. We also explore how precision medicine-based strategies can be leveraged to improve NSCLC brain metastases.

Prognostic Nomograms for Elderly Patients with Small Cell Lung Cancer Brain Metastasis: A Surveillance, Epidemiology, and End Results Population-Based Study with Temporal External Validation

This study aimed to pinpoint independent predictors influencing overall survival (OS) and cancer-specific survival (CSS) in elderly patients with small cell lung cancer (SCLC) brain metastasis (BM), and to create and validate nomograms for OS and CSS prediction. Data from elderly SCLC BM patients were extracted out of the Surveillance, Epidemiology, and End Results database, including 1200 patients identified from 2010 and 2015 who were randomly allocated into a training set and an internal validation set at a proportion of 7:3, and 666 patients diagnosed between 2018 and 2020 as a temporal external validation set. Independent predictors for OS and CSS were determined through univariate Cox analysis, least absolute shrinkage and selection operator analysis, and multivariate Cox analysis sequentially. Nomograms for OS and CSS were constructed, and validated by the internal and temporal external validation sets. Age, N stage, chemotherapy, and liver metastasis were determined as independent predictors of OS and CSS, while radiotherapy and surgery were not. Nomograms were constructed based on these independent predictors. The results of the receiver operator characteristic curves, the areas under the curve and calibration curve demonstrated that the nomograms exhibited commendable discriminative ability and calibration. Moreover, decision curve analysis, net reclassification improvement, and integrated discrimination improvement also suggested that the nomograms possessed superior clinical usefulness and predictive capability relative to the TNM system. Prognostic nomograms for elderly patients with SCLC BM have been developed, demonstrating good performance in terms of accuracy, reliability, and practicality.

Stereotactic radiosurgery in the management of non-small cell lung cancer brain metastases: a prospective study using the NeuroPoint Alliance Stereotactic Radiosurgery Registry.

The literature on non-small cell lung cancer (NSCLC) brain metastases (BMs) managed using stereotactic radiosurgery (SRS) relies mainly on single-institution studies or randomized controlled trials (RCTs). There is a literature gap on clinical and radiological outcomes of SRS for NSCLC metastases in real-world practice. The objective of this study was to benchmark mortality and progression outcomes in patients undergoing SRS for NSCLC BMs and identify risk factors for these outcomes using a national quality registry. The SRS Registry of the NeuroPoint Alliance was used for this study. This registry included patients from 16 enrolling sites who underwent SRS from 2017 to 2022. Data are prospectively collected without a prespecified research purpose. The main outcomes of this analysis were overall survival (OS), out-of-field recurrence, local progression, and intracranial progression. All time-to-event investigations included Kaplan-Meier analyses and multivariable Cox regressions. Two hundred sixty-four patients were identified, with a mean age of 66.7 years and a female proportion of 48.5%. Most patients (84.5%) had a Karnofsky Performance Status (KPS) score of 80-100, and the mean baseline EQ-5D score was 0.539 quality-adjusted life years. A single lesion was present in 53.4% of the patients, and 29.1% of patients had 3 or more lesions. The median OS was 28.1 months, and independent predictors of mortality included no control of primary tumor (hazard ratio [HR] 2.1), KPS of 80 (HR 2.4) or lower (HR 2.4), coronary artery disease (HR 2.8), and 5 or more lesions present at the time of SRS treatment (HR 2.3). The median out-of-field progression-free survival (PFS) was 24.8 months, and the median local PFS was unreached. Intralesional hemorrhage was an independent risk factor of local progression, with an HR of 6.0. The median intracranial PFS was 14.0 months and was predicted by the number of lesions at the time of SRS (3-4 lesions, HR 2.2; 5-14 lesions, HR 2.5). In this real-world prospective study, the authors used a national quality registry and found favorable OS in patients with NSCLC BMs undergoing SRS compared with results from previously published RCTs. The intracranial PFS was mainly driven by the emergence of new lesions rather than local progression. A greater number of lesions at baseline was associated with out-of-field progression, while intralesional hemorrhage at baseline was associated with local progression.

Short-term predictors of stereotactic radiosurgery outcome for untreated single non-small cell lung cancer brain metastases: a restrospective cohort study.

Stereotactic radiosurgery (SRS) is an option for brain metastases (BM) not eligible for surgical resection, however, predictors of SRS outcomes are poorly known. The aim of this study is to investigate predictors of SRS outcome in patients with BM secondary to non-small cell lung cancer (NSCLC). The secondary objective is to analyze the value of volumetric criteria in identifying BM progression. This retrospective cohort study included patients >18 years of age with a single untreated BM secondary to NSCLC. Demographic, clinical, and radiological data were assessed. The primary outcome was treatment failure, defined as a BM volumetric increase 12 months after SRS. The unidimensional measurement of the BM at follow-up was also assessed. One hundred thirty-five patients were included, with a median BM volume at baseline of 1.1 cm3 (IQR 0.4-2.3). Fifty-two (38.5%) patients had SRS failure at follow-up. Only right BM laterality was associated with SRS failure (p=0.039). Using the volumetric definition of SRS failure, the unidimensional criteria demonstrated a sensibility of 60.78% (46.11%-74.16%), specificity of 89.02% (80.18%-94.86%), positive LR of 5.54 (2.88-10.66) and negative LR of 0.44 (0.31-0.63). SRS demonstrated a 61.5% local control rate 12 months after treatment. Among the potential predictors of treatment outcome analyzed, only the right BM laterality had a significant association with SRS failure. The volumetric criteria were able to identify more subtle signs of BM increase than the unidimensional criteria, which may allow earlier diagnosis of disease progression and use of appropriate therapies.

CLO24-085: Precision Medicine Drivers in Non-Small Cell Lung Cancer Brain Metastases.

CLO24-085: Precision Medicine Drivers in Non-Small Cell Lung Cancer Brain Metastases.

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

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). 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. 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). 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.

Abstract 1797: Investigating the significance of OXPHOS activity in non-small cell lung cancer brain metastases

Abstract Background: Brain metastasis is a common and devastating occurrence for patients with non-small cell lung cancer (NSCLC). NSCLC patients with brain metastases have a poor median overall survival of 2-3 months, highlighting the urgency for novel treatment strategies. One approach to understanding and potentially targeting metastasis is via cancer metabolism. During the metastatic cascade, cancer cells must survive and adapt to the differential nutrient environments they encounter, including the brain. The blood brain barrier limits the availability of many metabolites, leading metastatic cells to alter their nutrient use to survive. RNA sequencing analyses of NSCLC brain metastases suggest that increased oxidative phosphorylation (OXPHOS) may be one such metabolic adaptation in the brain. The aim of this study was to determine the necessity of OXPHOS activity as a metabolic adaptation for NSCLC cells to proliferate in the unique metabolic environment of the brain. Materials and Methods: NSCLC cells were cultured in media mimicking the metabolic environments of the brain and blood. Expression of mitochondrial markers were evaluated by immunoblot in cells cultured across media conditions. The effects of the OXPHOS inhibitor IACS-010759 were assessed by cell growth as well as stable isotope tracing with [U-13C] glucose. Patient derived xenografts (PDXs) were derived from a cohort of patients with NSCLC who underwent stable isotope tracing with [U-13C] glucose. Mice bearing subcutaneously implanted PDXs were treated daily with 5mg/kg IACS-010759 and metastatic burden was measured by flow cytometry and histology. Results: Tracing studies in patients revealed that high enrichment in OXPHOS-related metabolites in the primary tumor correlated with worse patient outcomes. Compared with other media conditions, cells cultured in media replicating the metabolic environment of the brain have increased expression of mitochondrial proteins, increased 13C glucose labeling in the TCA cycle, and a larger reduction in proliferation with IACS-010759 treatment. Using our PDX models, inhibition of OXPHOS with IACS-010759 had little effect on subcutaneous tumor growth but reduced metastasis in the lung and the brain. Conclusions: OXPHOS activity may be enhanced in NSCLC brain metastases due to the unique metabolic environment of the brain. This elevated OXPHOS activity may be necessary for NSCLC brain metastasis growth, as OXPHOS inhibition reduced metastasis in the brain. NSCLC cells may undergo mitochondrial biogenesis to support survival in this unique metabolic environment, and this may represent an area of therapeutic vulnerability for brain metastases. Citation Format: Nia G. Hammond, Massar Alsamraae, Mayher Kaur, Rachel Zuckerman, Brianna Chang, Robert Cameron, Aaron Dyas, Brandon Faubert. Investigating the significance of OXPHOS activity in non-small cell lung cancer brain metastases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1797.

Durable response to first-line treatment with AZD3759 (zorifertinib) in a patient with epithelial growth factor receptor mutated non-small cell lung cancer and untreated multiple brain metastasis

Central nervous system (CNS) metastases, including brain and leptomeningeal metastasis, are associated with poor prognosis in epidermal growth factor receptor (&lt;i&gt;EGFR&lt;/i&gt;)-mutated non-small cell lung cancer (NSCLC) patients. CNS metastasis occurs in more than 50% of &lt;i&gt;EGFR&lt;/i&gt;-mutated NSCLC cases during the treatment course. The treatment options for CNS metastases in these patients are limited, and there have been ongoing efforts to develop targeted agents with enhanced CNS penetration. AZD3759 (zorifertinib) is a novel &lt;i&gt;EGFR&lt;/i&gt; tyrosine kinase inhibitor with a high capability of CNS penetration and proven efficacy with tolerable safety profiles. In this report, we describe a case of a patient with &lt;i&gt;EGFR&lt;/i&gt;-mutant NSCLC that was initially diagnosed with multiple brain metastasis who demonstrated prolonged response of both intra- and extracranial lesions over 7 years with AZD3759 as first-line treatment.

Current approaches in the diagnosis and management of non-small cell lung cancer brain metastases

Brain metastases are a frequent consequence of “non-small cell lung cancer (NSCLC)”, one of the most prevalent cancers with a poor prognosis. For the best possible patient outcomes, detecting and treating NSCLC brain metastases involve substantial hurdles and calls for a multidisciplinary approach. This article intends to provide an overview of current methods for diagnosing and treating NSCLC brain metastases. It examines the various available treatment options, diagnostic techniques, and their effects on patient outcomes. A thorough literature review was done to find pertinent studies, clinical suggestions, and professional advice about the specialized management of NSCLC. The chosen articles were examined to learn about molecular screening techniques, individualized treatment plans, and diagnostic procedures. For individualized treatment, precise NSCLC identification and prognosis are essential. Techniques such as imaging and endoscopy are used to collect tissue samples. It is advised to do a molecular screening for oncogenic changes. Evaluation of PD-L1 expression informs therapy decisions. The molecular profile determines the first line of treatment, followed by chemotherapy and immunotherapy, and cancer tissue samples help to detect resistance mechanisms. For the best possible patient results, NSCLC therapy must be personalized and incorporate precise pathology evaluation, molecular assessment, and precision therapeutic approaches. To progress in precision medicine in lung cancer treatment, further research is required to find novel molecular markers, especially those that predict the effectiveness of immunotherapy.

Long-Term Intracranial Outcomes With Combination Dual Immune-Checkpoint Blockade and Stereotactic Radiosurgery in Patients With Melanoma and Non-Small Cell Lung Cancer Brain Metastases

The intracranial benefit of offering dual immune-checkpoint inhibition (D-ICPI) with ipilimumab and nivolumab to patients with melanoma or non-small cell lung cancer (NSCLC) receiving stereotactic radiosurgery (SRS) for brain metastases (BMs) is unknown. We hypothesized that D-ICPI improves local control compared with SRS alone. Patients with melanoma or NSCLC treated with SRS from 2014 to 2022 were evaluated. Patients were stratified by treatment with D-ICPI, single ICPI (S-ICPI), or SRS alone. Local recurrence, intracranial progression (IP), and overall survival were estimated using competing risk and Kaplan-Meier analyses. IP included both local and distant intracranial recurrence. Two hundred eighty-eight patients (44% melanoma, 56% NSCLC) with 1,704 BMs were included. Fifty-three percent of patients had symptomatic BMs. The median follow-up was 58.8 months. Twelve-month local control rates with D-ICPI, S-ICPI, and SRS alone were 94.73% (95% CI, 91.11%-96.90%), 91.74% (95% CI, 89.30%-93.64%), and 88.26% (95% CI, 84.07%-91.41%). On Kaplan-Meier analysis, only D-ICPI was significantly associated with reduced local recurrence (P = .0032). On multivariate Cox regression, D-ICPI (hazard ratio [HR], 0.4003; 95% CI, 0.1781-0.8728; P = .0239) and planning target volume (HR, 1.022; 95% CI, 1.004-1.035; P = .0059) correlated with local control. One hundred seventy-three (60%) patients developed IP. The 12-month cumulative incidence of IP was 41.27% (95% CI, 30.27%-51.92%), 51.86% (95% CI, 42.78%-60.19%), and 57.15% (95% CI, 44.98%-67.59%) after D-ICPI, S-ICPI, and SRS alone. On competing risk analysis, only D-ICPI was significantly associated with reduced IP (P = .0408). On multivariate Cox regression, D-ICPI (HR, 0.595; 95% CI, 0.373-0.951; P = .0300) and presentation with >10 BMs (HR, 2.492; 95% CI, 1.668-3.725; P < .0001) remained significantly correlated with IP. The median overall survival after D-ICPI, S-ICPI, and SRS alone was 26.1 (95% CI, 15.5-40.7), 21.5 (16.5-29.6), and 17.5 (11.3-23.8) months. S-ICPI, fractionation, and histology were not associated with clinical outcomes. There was no difference in hospitalizations or neurologic adverse events between cohorts. The addition of D-ICPI for patients with melanoma and NSCLC undergoing SRS is associated with improved local and intracranial control. This appears to be an effective strategy, including for patients with symptomatic or multiple BMs.

Using machine learning-based radiomics to differentiate between glioma and solitary brain metastasis from lung cancer and its subtypes

ObjectiveTo establish a machine learning-based radiomics model to differentiate between glioma and solitary brain metastasis from lung cancer and its subtypes, thereby achieving accurate preoperative classification.Materials and methodsA retrospective analysis was conducted on MRI T1WI-enhanced images of 105 patients with glioma and 172 patients with solitary brain metastasis from lung cancer, which were confirmed pathologically. The patients were divided into the training group and validation group in an 8:2 ratio for image segmentation, extraction, and filtering; multiple layer perceptron (MLP), support vector machine (SVM), random forest (RF), and logistic regression (LR) were used for modeling; fivefold cross-validation was used to train the model; the validation group was used to evaluate and assess the predictive performance of the model, ROC curve was used to calculate the accuracy, sensitivity, and specificity of the model, and the area under curve (AUC) was used to assess the predictive performance of the model.ResultsThe accuracy and AUC of the MLP differentiation model for high-grade glioma and solitary brain metastasis in the validation group was 0.992, 1.000, respectively, while the sensitivity and specificity were 1.000, 0.968, respectively. The accuracy and AUC for the MLP and SVM differentiation model for high-grade glioma and small cell lung cancer brain metastasis in the validation group was 0.966, 1.000, respectively, while the sensitivity and specificity were 1.000, 0.929, respectively. The accuracy and AUC for the MLP differentiation model for high-grade glioma and non-small cell lung cancer brain metastasis in the validation group was 0.982, 0.999, respectively, while the sensitivity and specificity were 0.958, 1.000, respectively.ConclusionThe application of machine learning-based radiomics has a certain clinical value in differentiating glioma from solitary brain metastasis from lung cancer and its subtypes. In the HGG/SBM and HGG/NSCLC SBM validation groups, the MLP model had the best diagnostic performance, while in the HGG/SCLC SBM validation group, the MLP and SVM models had the best diagnostic performance.

Abstract LB_A04: Quantitative digital spatial protein profiling of non-small cell lung cancer brain metastasis

Abstract Metastatic brain tumor is the most common form of adult central nervous system (CNS) tumor, and the majority of the cerebral metastasis originate from lung cancer. Along with recent combination strategies applying immune checkpoint inhibitor, evaluating tumor microenvironment of the brain metastasis (BM) needs to be unveiled. In this study, we tried to disclose immune context information of BM of non-small cell lung cancer (NSCLC) by using highly multiplex NanoString digital spatial profiling (DSP) method. Seven cases of NSCLC and metastatic brain tumor were evaluated. To detect proteins at quantitative and high multiplex with spatial resolution, NanoString optical barcoding technology was used to digitally profile protein expression in FFPE samples. Immuno-oncology protein targets, including immune cell markers and checkpoint proteins are included. DSP identified differentially expressed proteins between primary NSCLC and BM. Proteins associated with immune regulation, evasion, and adaptive immunity, such as IDO-1, PD1, PDL1, STAT3, PTEN, and CD44 revealed decreased expression in patients with BM (P&amp;lt;0.01). The expression of pS6 was significantly increased in BM (P&amp;lt;0.01), which is associated with activation induced T-cell death. This study demonstrated differentially expressed proteins in BM associated with immune regulation and evasion via NanoString DSP platform. This study highlighted the localized expression of immune-related proteins of BM in patients with NSCLC. Moreover, our results presented the possibility of using digitally quantified and spatially allocated novel method in BM eliminating the subjectivity and variability associated with the immunohistochemistry techniques. Citation Format: Tae Jung Kim. Quantitative digital spatial protein profiling of non-small cell lung cancer brain metastasis [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr LB_A04.

Use of comprehensive genomic profiling for biomarker discovery for the management of non-small cell lung cancer brain metastases.

Clinical biomarkers for brain metastases remain elusive. Increased availability of genomic profiling has brought discovery of these biomarkers to the forefront of research interests. In this single institution retrospective series, 130 patients presenting with brain metastasis secondary to Non-Small Cell Lung Cancer (NSCLC) underwent comprehensive genomic profiling conducted using next generation circulating tumor deoxyribonucleic acid (DNA) (Guardant Health, Redwood City, CA). A total of 77 genetic mutation identified and correlated with nine clinical outcomes using appropriate statistical tests (general linear models, Mantel-Haenzel Chi Square test, and Cox proportional hazard regression models). For each outcome, a genetic signature composite score was created by summing the total genes wherein genes predictive of a clinically unfavorable outcome assigned a positive score, and genes with favorable clinical outcome assigned negative score. Seventy-two genes appeared in at least one gene signature including: 14 genes had only unfavorable associations, 36 genes had only favorable associations, and 22 genes had mixed effects. Statistically significant associated signatures were found for the clinical endpoints of brain metastasis velocity, time to distant brain failure, lowest radiosurgery dose, extent of extracranial metastatic disease, concurrent diagnosis of brain metastasis and NSCLC, number of brain metastases at diagnosis as well as distant brain failure. Some genes were solely associated with multiple favorable or unfavorable outcomes. Genetic signatures were derived that showed strong associations with different clinical outcomes in NSCLC brain metastases patients. While these data remain to be validated, they may have prognostic and/or therapeutic impact in the future. Using Liquid biopsy in NSCLC brain metastases patients, the genetic signatures identified in this series are associated with multiple clinical outcomes particularly these ones that lead to early or more numerous metastases. These findings can be reverse-translated in laboratory studies to determine if they are part of the genetic pathway leading to brain metastasis formation.

2004P PD-L1 Inhibitors combined with whole brain radiotherapy in patients with small cell lung cancer brain metastases: Real-world evidence

2004P PD-L1 Inhibitors combined with whole brain radiotherapy in patients with small cell lung cancer brain metastases: Real-world evidence

1419P TACSTD2 (Trop-2) constitutes a promising antibody-drug conjugate target for patients with non-small cell lung cancer brain metastases

1419P TACSTD2 (Trop-2) constitutes a promising antibody-drug conjugate target for patients with non-small cell lung cancer brain metastases

Hippocampal Avoidance Whole Brain Radiotherapy with Reduced Whole Brain Dose in Patients with Non-Small Cell Lung Cancer Brain Metastases

Hippocampal avoidance whole brain radiation (HA-WBRT) results in improved neurocognitive function (NCF) compared to standard WBRT, but > 50% of patients still experience NCF failure. We examined whether gentler fractionation of HA-WBRT with lower biologically effective dose (BED), typically delivering 30 Gy over 15 versus 10 fractions, may allow for better hippocampal sparing without impacting intracranial disease control in patients with non-small cell lung cancer (NSCLC). We conducted a retrospective study of patients with NSCLC receiving HA-WBRT between 2014-2022. Endpoints were distant brain failure free survival (DBFFS), local brain failure free survival (LBFFS), left and right hippocampal mean BED2 and BED21%. Kaplan-Meier survival analysis and Welch's t-test were performed. NCF outcomes were graded with CTCAEv5. The IRB approved this study. Sixty-nine consecutive patients treated with HA-WBRT were included, with median follow up of 51.2 weeks. Median age was 63 years and 29% had a targetable mutation. Thirty-six patients received standard HA-WBRT with median dose of 30 Gy (range 30-35 Gy) in 10 fractions (range 10-14). Thirty-three patients received reduced BED HA-WBRT, with median dose of 30 Gy (range 23-30) in 15 fractions (range 9-15) to the radiographically uninvolved brain. All patients in the reduced BED (RD) group had a simultaneous integrated boost (SIB) to gross disease (median 37.5 Gy (range 36-37.5 Gy)), while 18/36 in the standard dose (SD) group had an SIB (median 35 Gy (range 34-39 Gy)). There were no significant differences between SD and RD cohorts in age, systemic therapy use before WBRT or targetable mutations. There was no significant difference in median DBFFS of the SD [23.1 weeks (IQR 11.3-49.3)] and RD groups [40 weeks, (IQR 20.9-109.1)] (p = 0.27). There was also no difference in LBFFS of the SD (median 26.4 weeks, IQR 11.3-76.2) and RD groups (median 40 weeks, IQR (21-71.4) (p = 0.84). For the left and right hippocampi, both mean BED2 and D1% were significantly lower in the RD group (Table 1). Median cognitive disturbance was Grade (G) 0 (range 0-3) in both groups, with 4 G>2 events in the SD cohort vs. 3 in the RD cohort. In this single-institution cohort, HA-WBRT using a gentler fractionation with SIB was associated with improved hippocampal sparing without compromising intracranial control in patients with NSCLC. We suggest that further optimization of HA-WBRT dose and schedule may improve both intracranial control and NCF outcomes. This study is limited by its retrospective nature and potential selection bias. A phase II prospective study to test these concepts is ongoing.

Immune Checkpoint Inhibition and Single Fraction Stereotactic Radiosurgery in Non-Small Cell Lung Cancer Brain Metastases: An International Multicenter Study of 395 Patients

Brain metastases most commonly arise from non-small cell lung cancer (NSCLC). In recent years, immune checkpoint inhibitors (ICI) have demonstrated improvements in overall survival (OS) in NSCLC. However, concerns remain about the risk of radiation necrosis (RN) when ICI are administered with stereotactic radiosurgery (SRS). Logistic regression was used to evaluate prognostic factors associated with the development of any grade RN and symptomatic RN. Cumulative incidence of RN was evaluated using competing risks analysis and the Fine and Gray model, where the null hypothesis was rejected for p < 0.05. There were 395 patients with 2,513 brain metastases treated across 11 international institutions included in the analysis. The median follow-up was 14.2 months. Median patient age was 67 years (Interquartile Range [IQR]: 61-73), 53.4% were male, the median Karnofsky Performance Status was 80 (IQR: 80-90), and 88.6% has active extracranial disease at the time of SRS. The median margin dose was 19 Gy (IQR: 18-20), 97.5% of patients were treated on the Gamma Knife ®, 3.8% underwent prior whole brain radiation therapy (WBRT). The median V12 Gy was 5.2 cm3 and 36.5% of patients had a V12 Gy ≥ 10 cm3, anti-PD-1 agents were administered in 91.6% of patients. A V12 Gy ³ 10 cm3 was associated with an increased risk of developing any grade RN; odds ratio (OR): 2.12, p = 0.04 and OR: 2.18; p = 0.03 on univariable and multivariable analysis, respectively. Similarly, a V12 Gy ≥ 10 cm3 was associated with an increased risk of developing symptomatic RN; OR: 3.80, p = 0.003 and OR: 3.95; p = 0.003 on univariable and multivariable analysis, respectively. Receipt of concurrent ICI and prior WBRT were not statistically significant. At 1-year, the cumulative incidence of any grade and symptomatic RN was 4.8% and 3.8%, respectively. The cumulative incidence of any grade RN was 3.8% vs. 5.3% for the concurrent and non-concurrent groups at 1-year, respectively (p = 0.35). The cumulative incidence of symptomatic RN was 3.8% vs. 3.6% for the concurrent and non-concurrent groups at 1-year, respectively (p = 0.95). The risk of any grade and symptomatic RN following SRS and ICI administration for NSCLC brain metastases increases as the V12 Gy exceeds 10 cm3. Concurrent ICI and SRS does not appear to increase this risk. Radiosurgical planning techniques should aim to minimize the V12 Gy.

The Impact of Time Interval on Prognosis in Patients with Non-Small Cell Lung Cancer Brain Metastases After Metastases Surgery

Non-small cell lung cancer (NSCLC) is a prominent malignancy often linked to the development of brain metastases (BM), which commonly appear at diverse time intervals (TI) following the lung cancer diagnosis. This study endeavors to determine the prognostic significance of the time interval in patients with NSCLC who undergo BM surgery. Through this investigation, we aim to improve our understanding of the factors impacting the prognosis of BM cases originating from NSCLC. We analyzed data from 74 patients (2011-2021) who underwent BM surgery at our institution. The relationship between various clinical, radiological, and histopathological factors, as well as TI and overall survival (OS), was examined. The median TI from initial NSCLC diagnosis to BM surgery was 19months (range: 9-36months). Notably, a shorter TI of less than 23months was found to be independently associated with postoperative survival (adjusted odds ratio [aOR] 2.87, 95% confidence interval [CI] 1.03-8.02, P= 0.045). Additionally, a shorter TI was independently correlated with the absence of adjuvant chemotherapy for NSCLC (aOR 0.25, 95% CI 0.07-0.83, P= 0.023) and lack of targeted therapy (aOR 0.02, 95% CI 0.00-0.16, P<0.001). Late-onset BM (TI≥36months) was observed in 15 cases (20.3%), in this subgroup, patients aged 60years or older at the time of lung cancer diagnosis exhibited a significant independent correlation with late-onset BM (aOR 7.24, 95% CI 1.59-32.95, P= 0.011). NSCLC patients who underwent adjuvant chemotherapy displayed a notable correlation with late-onset BM (aOR 6.46, 95% CI 1.52-27.43, P= 0.011), while those who received targeted therapy also exhibited an independent association (aOR 2.27, 95% CI 1.70-3.03, P < 0.001). Multiple factors contribute to the variability in the onset interval of BM subsequent to NSCLC diagnosis. The occurrence of BM within TI<23months following the initial diagnosis of NSCLC was demonstrated as an independent factor associated with an unfavorable prognosis following BM surgery. Furthermore, patients with NSCLC who did not receive adjuvant chemotherapy and lacked targeted therapy were shown to have an elevated likelihood of developing BM after a long progression-free survival.