Cumulative incidence and risk factors of brain metastases in metastatic non-small cell lung cancer without baseline brain metastasis: Pooled analysis of individualized patient data from IMpower130, IMpower131, and IMpower150.

BACKGROUND: The objective of this study was to explore the abilities of atezolizumab plus chemotherapy in preventing brain metastases (BMs) among metastatic non-small cell lung cancer (NSCLC) without initial BMs, as well as the risk factors of BMs. METHODS: Individual patient data from three trials involving first-line atezolizumab for metastatic NSCLC (IMpower130, IMpower131, and IMpower150) were pooled. Among patients without baseline BMs and without epidermal growth factor receptor (EGFR) and/or anaplastic lymphoma kinase (ALK) mutations, those receiving atezolizumab + chemotherapy ± bevacizumab were classified as the atezolizumab plus chemotherapy group and those receiving placebo + chemotherapy ± bevacizumab were classified as the chemotherapy group. The cumulative incidences of BM (CI-BMs) between the two groups were compared. Other factors associated with the CI-BM were analyzed by Cox regression analyses. RESULTS: With a median follow-up of 17.6 months (range, 0.03-33.64 months), 74 (3.1%) of the 2380 enrolled patients developed BMs, including 50 (3.1%) and 24 (3.0%) in the atezolizumab plus chemotherapy group (n = 1589) and the chemotherapy group (n = 791), respectively. The CI-BMs at 6, 12, and 24 months were 1.7%, 2.8%, and 3.3%, respectively. After taking competing risk events into account, there was no significant difference in the CI-BMs between the two groups (p = .888). Nevertheless, the use of bevacizumab and the histology of nonsquamous NSCLC were found to be independently associated with the risk of BMs. CONCLUSIONS: In patients with metastatic EGFR/ALK wild-type NSCLC without baseline BMs, adding atezolizumab in the first-line treatment might not reduce the CI-BM. However, the administration of bevacizumab may reduce the risk of BMs.

Laser interstitial thermal therapy followed by consolidation stereotactic radiosurgery (LITT-cSRS) in patients with newly diagnosed brain metastasis.

INTRODUCTION: The efficacy and safety of laser interstitial thermal therapy followed by consolidation radiosurgery (LITT-cSRS) was previously studied in brain metastasis that recurs locally after initial radiosurgery (BMRS). Here, we characterize the clinical outcome of LITT-cSRS in patients with newly diagnosed brain metastasis. METHODS: Between 2017 and 2023, ten consecutive cancer patients with newly diagnosed brain mass of unclear etiology who underwent stereotactic needle biopsy (SNB) and LITT in the same setting followed by consolidation SRS (cSRS) with > 6 months follow-up were identified retrospectively. Clinical and imaging outcomes were collected. RESULTS: The histology of the BM were: breast cancer (n = 3), melanoma (n = 3), non-cell cell lung cancer (n = 3), colon (n = 1). There were no wound or procedural complications. All patients were discharged home, with a median one-day hospital stay (range: 1-2 days). All patients were off corticosteroid therapy by the one-month follow-up. cSRS were carried out 12-27 days (median of 19 days) after SNB + LITT. There were no subsequent emergency room presentation, 30-day or 90-day re-admission. The Karnofsky Performance Score (KPS) remains stable or improved at the 3 months-follow-up. With a median follow-up of 416 days (13.8 mo; range: 199-1,096 days), there was one local recurrence at 384 days (12.8 mo) post-LITT-cSRS. With exception of this patient with local recurrence, all patients showed decreased FLAIR volume surrounding the LITT-cSRS treated BMRS by the six-month follow-up. CONCLUSIONS: To our awareness, this case series represent the first to describe LITT-cSRS in the setting of newly diagnosed BM. The results presented here provide pilot data to support the safety and efficacy of LITT-cSRS and lay the foundation for future studies.

Management strategies for intracranial progression in ALK-positive non-small cell lung cancer: a real-world cohort study.

PURPOSE: ALK-positive NSCLC patients exhibit a particularly high propensity for the development of brain metastases. Current guidelines suggest transit to next-line therapy (SysTx) or local radiotherapy (RadTx) including whole-brain radiotherapy and radiosurgery. However, the clinical impact of these two strategies remains unclear. METHODS: We conducted a retrospective analysis focusing on patients with stage IV ALK-positive NSCLC who underwent first-line ALK TKI treatment. Patients with intracranial progression may receive two different treatment strategies: SysTx and RadTx. Our objective was to investigate the outcomes associated with these two distinct treatment pathways. RESULTS: A total 20 patients of ALK-positive NSCLC who received first-line ALK TKI therapy and subsequently developed intracranial progression were enrolled. About 55% of patients had brain metastasis initially. Nine patients (45%) were treated with crizotinib at first. Patients treated with crizotinib demonstrated a significantly shorter intracranial PFS1 (crizotinib: 8.27 months vs. others: 27.0 months, p = 0.006). Following intracranial progression, approximately 60% of patients transitioned to the next line of systemic treatment (SysTx), while the remaining 40% opted for local cranial radiotherapy (RadTx). Intriguingly, our analysis revealed no statistically significant difference in intracranial progression-free survival (PFS2) between these two distinct treatment strategies. (SysTx: 20.87 months vs. RadTx: 28.23 months, p = 0.461). CONCLUSION: The intracranial progression-free survival showed no difference between the two strategies suggesting that both local radiotherapy and systemic therapy may be valid options. Individualized strategy, molecular analysis, and multidisciplinary conferences may all play a pivotal role in decision-making.

Stereotactic Laser Ablation (SLA) followed by consolidation stereotactic radiosurgery (cSRS) as treatment for brain metastasis that recurred locally after initial radiosurgery (BMRS): a multi-institutional experience.

INTRODUCTION: The optimal treatment paradigm for brain metastasis that recurs locally after initial radiosurgery remains an area of active investigation. Here, we report outcomes for patients with BMRS treated with stereotactic laser ablation (SLA, also known as laser interstitial thermal therapy, LITT) followed by consolidation radiosurgery. METHODS: Clinical outcomes of 20 patients with 21 histologically confirmed BMRS treated with SLA followed by consolidation SRS and > 6 months follow-up were collected retrospectively across three participating institutions. RESULTS: Consolidation SRS (5 Gy × 5 or 6 Gy × 5) was carried out 16-73 days (median of 26 days) post-SLA in patients with BMRS. There were no new neurological deficits after SLA/cSRS. While 3/21 (14.3%) patients suffered temporary Karnofsky Performance Score (KPS) decline after SLA, no KPS decline was observed after cSRS. There were no 30-day mortalities or wound complications. Two patients required re-admission within 30 days of cSRS (severe headache that resolved with steroid therapy (n = 1) and new onset seizure (n = 1)). With a median follow-up of 228 days (range: 178-1367 days), the local control rate at 6 and 12 months (LC6, LC12) was 100%. All showed diminished FLAIR volume surrounding the SLA/cSRS treated BMRS at the six-month follow-up; none of the patients required steroid for symptoms attributable to these BMRS. These results compare favorably to the available literature for repeat SRS or SLA-only treatment of BMRS. CONCLUSIONS: This multi-institutional experience supports further investigations of SLA/cSRS as a treatment strategy for BMRS.

Where Are We Now and Where Might We Be Headed in Understanding and Managing Brain Metastases in Colorectal Cancer Patients?

OPINION STATEMENT: Compared to liver and lung metastases, brain metastases (BMs) from colorectal cancer (CRC) are rare and remain poorly investigated despite the anticipated rise in their incidence. CRC patients bearing BM have a dismal prognosis with a median survival of 3-6 months, significantly lower than that of patients with BM from other primary tumors, and of those with metastatic CRC manifesting extracranially. While liver and lung metastases from CRC have more codified treatment strategies, there is no consensus regarding the treatment of BM in CRC, and their management follows the approaches of BM from other solid tumors. Therapeutic strategies are driven by the number and localisation of the lesion, consisting in local treatments such as surgery, stereotactic radiosurgery, or whole-brain radiotherapy. Novel treatment modalities are slowly finding their way into this shy unconsented armatorium including immunotherapy, monoclonal antibodies, tyrosine kinase inhibitors, or a combination of those, among others.This article reviews the pioneering strategies aiming at understanding, diagnosing, and managing this disease, and discusses future directions, challenges, and potential innovations in each of these domains. HIGHLIGHTS: • With the increasing survival in CRC, brain and other rare/late-onset metastases are rising. • Distal colon/rectal primary location, long-standing progressive lung metastases, and longer survival are risk factors for BM development in CRC. • Late diagnosis and lack of consensus treatment strategies make BM-CRC diagnosis very dismal. • Liquid biopsies using circulating tumor cells might offer excellent opportunities in the early diagnosis of BM-CRC and the search for therapeutic options. • Multi-modality treatment including surgical metastatic resection, postoperative SRS with/without WBRT, and chemotherapy is the best current treatment option. • Recent mid-sized clinical trials, case reports, and preclinical models show the potential of unconventional therapeutic approaches as monoclonal antibodies, targeted therapies, and immunotherapy. Graphical abstract.

Mesothelin promotes brain metastasis of non-small cell lung cancer by activating MET.

BACKGROUND: Brain metastasis (BM) is common among cases of advanced non-small cell lung cancer (NSCLC) and is the leading cause of death for these patients. Mesothelin (MSLN), a tumor-associated antigen expressed in many solid tumors, has been reported to be involved in the progression of multiple tumors. However, its potential involvement in BM of NSCLC and the underlying mechanism remain unknown. METHODS: The expression of MSLN was validated in clinical tissue and serum samples using immunohistochemistry and enzyme-linked immunosorbent assay. The ability of NSCLC cells to penetrate the blood-brain barrier (BBB) was examined using an in vitro Transwell model and an ex vivo multi-organ microfluidic bionic chip. Immunofluorescence staining and western blotting were used to detect the disruption of tight junctions. In vivo BBB leakiness assay was performed to assess the barrier integrity. MET expression and activation was detected by western blotting. The therapeutic efficacy of drugs targeting MSLN (anetumab) and MET (crizotinib/capmatinib) on BM was evaluated in animal studies. RESULTS: MSLN expression was significantly elevated in both serum and tumor tissue samples from NSCLC patients with BM and correlated with a poor clinical prognosis. MSLN significantly enhanced the brain metastatic abilities of NSCLC cells, especially BBB extravasation. Mechanistically, MSLN facilitated the expression and activation of MET through the c-Jun N-terminal kinase (JNK) signaling pathway, which allowed tumor cells to disrupt tight junctions and the integrity of the BBB and thereby penetrate the barrier. Drugs targeting MSLN (anetumab) and MET (crizotinib/capmatinib) effectively blocked the development of BM and prolonged the survival of mice. CONCLUSIONS: Our results demonstrate that MSLN plays a critical role in BM of NSCLC by modulating the JNK/MET signaling network and thus, provides a potential novel therapeutic target for preventing BM in NSCLC patients.

Potential synergistic effects of cranial radiotherapy and atezolizumab in non-small cell lung cancer: an analysis of individual patient data from seven prospective trials.

Background: The impact of cranial radiotherapy (RT) on overall survival (OS) of patients with brain metastasis (BM) from non-small cell lung cancer (NSCLC) receiving programmed death 1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors remains unclear. We aimed to examine the effect of previous cranial RT on the efficacy and neurological toxicity of PD-1/PD-L1 inhibitors in the treatment of patients with NSCLC. Methods: Patient-level data from seven prospective trials involving atezolizumab for the treatment of NSCLC [BIRCH (NCT02031458), FIR (NCT01846416), IMpower130 (NCT02367781), IMpower131 (NCT02367794), IMpower150 (NCT02366143), OAK (NCT02008227), and POPLAR (NCT01903993)] were pooled. Patients with baseline BM were divided into two subgroups based on previous cranial RT before initiation of treatment: patients with previously irradiated BM (iBM) and patients with non-irradiated BMs (niBM). Results: The per-protocol population consisted of 4,714 patients, including 3,176 in the atezolizumab group and 1,538 in the comparator chemotherapy group. In the atezolizumab group, OS was better in patients with BM (n=308) compared to patients without BM (n=2,868) [hazard ratio (HR): 0.83; 95% confidence interval (CI): 0.70-0.98; P=0.028]. Among patients with BM, patients with iBM (n=280) had a numerically longer OS (HR: 0.66; 95% CI: 0.41-1.07; P=0.090) than those with niBM (n=28). Intriguingly, OS was longer in patients with iBM than those without BM before (HR: 0.83; 95% CI: 0.70-0.99; P=0.043) and after (HR: 0.40; 95% CI: 0.32-0.49; P<0.0001) propensity score matching, while OS was similar between patients with niBM and those without BM. The survival advantage of patients with iBM over those without BM was not observed in the chemotherapy group. Atezolizumab-related serious neurological adverse events occurred in 16 (0.6%) patients without BM, none in those with niBM, and 2 (0.7%) patients with iBM. Conclusions: These data suggest potential synergistic effects of cranial RT and anti-PD-(L)1 therapy in NSCLC patients, which warrants further validation.

Intracranial response pattern, tolerability and biomarkers associated with brain metastases in non-small cell lung cancer treated by tislelizumab plus chemotherapy.

Background: Programmed cell death protein-1/programmed cell death protein-ligand 1 (PD-1/PD-L1) inhibitor and chemotherapy are the standard treatment for advanced non-small cell lung cancer (NSCLC) without sensitizing mutations. However, patients with untreated, symptomatic or recently-irradiated brain metastases (BMs) are mostly excluded from immunochemotherapy trials. This study aims to evaluate the intracranial response pattern, tolerability and biomarkers of tislelizumab plus chemotherapy in NSCLC with untreated, symptomatic or recently-irradiated BM. Methods: This multicenter, single-arm, phase 2 trial enrolled patients with treatment-naïve, brain-metastasized NSCLC. BM could be untreated or irradiated. Symptomatic or recently-irradiated BMs that were deemed clinically stable were allowed. Patients received tislelizumab (200 mg) plus pemetrexed (500 mg/m2) and carboplatin (AUC =5) on day 1 every 3 weeks for 4 cycles, followed by maintenance with tislelizumab plus pemetrexed. Primary endpoint was 1-year progression-free survival (PFS) rate. Secondary endpoints included intracranial efficacy and tolerability. PD-L1 expression, tumor mutational burden (TMB) and genomic alterations were evaluated as potential biomarkers. Results: A total of 36 patients were enrolled, 19.2% had prior brain radiotherapy, 8.3% had symptomatic BMs that required corticosteroids ≤10 mg/d or antiepileptics. Confirmed systemic and intracranial ORR (iORR) was 43.8% and 46.7%, respectively. One-year systematic PFS rate and One-year iPFS rate was 36.8% and 55.8%, respectively. About 41.7% patients had neurological adverse events, 90% patients had concordant intracranial-extracranial responses. No intracranial pseudoprogression or hyperprogression occurred. Patients with prior brain radiation trended towards higher systemic (83.3% vs. 34.6%) and iORR (75.0% vs. 42.3%). Similar intracranial efficacy was observed in tumors with different PD-L1 and TMB levels, while alterations in cytokine receptors pathway predicted higher iORR (P=0.081), prolonged systematic PFS [hazard ratio (HR) =0.16, P=0.021] and overall survival (OS) (HR =0.71, P=0.029). Conclusions: Untreated or irradiated BMs in NSCLC follows a conventional response and progression pattern under immunochemotherapy with altered cytokine receptors pathway being a potential biomarker for systemic and intracranial outcomes.

Immune checkpoint inhibitors as subsequent treatment in older adults with non-small cell lung cancer and synchronous brain metastases.

Background: Immune checkpoint inhibitors (ICIs) have become the mainstay treatment for non-small cell lung cancer (NSCLC). However, there is a lack of studies assessing ICIs as subsequent treatment in older adults with NSCLC and brain metastasis (BM). This retrospective cohort study compared the real-world survival of older patients with NSCLC and BM at diagnosis [synchronous BM (SBM)] previously treated with chemotherapy receiving ICI versus chemotherapy as subsequent treatment. Methods: Patients with NSCLC and SBM ≥65 years previously treated with chemotherapy were identified using the SEER-Medicare database (2010-2019). Patients receiving new chemotherapy and/or Food and Drug Administration (FDA)-approved ICIs as second/third-line treatment were included, excluding those ever-receiving targeted therapies. Each ICI patient was matched to one chemotherapy patient by time to subsequent treatment (within ±30 days) from diagnosis. Overall survival (OS) time was measured from the start of subsequent treatment to death, censored at disenrollment from Medicare Part A/B, enrollment in Part C, or end of study (December 31, 2019), whichever came first. OS curves were estimated and compared using the Kaplan-Meier (KM) method and log-rank test. Hazard ratio (HR) was estimated using a multivariable-adjusted Cox proportional hazards model. Results: Matched cohorts included 546 patients [273 in each group; median age 71 (range, 65-87) years]. ICI patients were older, more likely non-Hispanic, with squamous cell carcinoma, and liver metastasis compared to chemotherapy. KM estimated better survival in ICI than chemotherapy {median survival: 209 days [95% confidence interval (CI): 160-275] vs. 155 days (95% CI: 135-187); log-rank P<0.001}. ICI was associated with a lower adjusted hazard of death [HR =0.63; 95% CI: 0.52-0.75; P<0.001] compared to subsequent chemotherapy treatment. Conclusions: In this population-based study of older patients with NSCLC and SBM previously treated with chemotherapy, subsequent treatment with ICI was associated with improved survival compared to chemotherapy.

A model for predicting clinical prognosis based on brain metastasis-related genes in patients with breast cancer.

Background: Brain metastasis (BM) is a clinically relevant cause of death in patients with breast cancer (BRCA). This study was designed to develop a clinical model capable of predicting BRCA patients' prognostic outcomes according to the expression of BM-related genes (BMRGs). Methods: The public Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases served as data sources. BMRGs of BRCA were selected from previous literature. Differences among BRCA molecular subtypes were compared using R 'limma' package. The impact of BM-related differentially expressed genes (BM_DEGs) on BRCA patients' outcomes was explored with a risk score model, after which the relationship between these risk scores and immune cell infiltration was examined. Risk scores were also used to judge the predicted efficacy of immunotherapeutic interventions. The utility of risk scores in combination with clinicopathological characteristics was evaluated as a predictor of patient's survival through univariate and multivariate analyses. Results: The R limma package was used to explore differential gene expression, after which 12 BM_DEGs were incorporated into a risk scoring model. The resultant risk scores were able to predict immunotherapeutic treatment efficacy. In addition, a nomogram incorporating risk scores, stage, and age was established. The nomogram was able to reliably predict the overall survival (OS) of BRCA patients, yielding predictive outcomes that aligned well with actual observations. Conclusions: In summary, a predictive clinical model for BRCA patients was successfully established in this study, providing a valuable tool that may be particularly helpful for the assessment of patients facing a risk of BM development.

The emerging potential of quantitative MRI biomarkers for the early prediction of brain metastasis response after stereotactic radiosurgery: a scoping review.

Background: At present, the simple prognostic models based on clinical information for predicting the treatment outcomes of brain metastases (BMs) are subjective and delayed. Thus, we performed this systematic review of multiple studies to assess the potential of quantitative magnetic resonance imaging (MRI) biomarkers for the early prediction of treatment outcomes of brain metastases with stereotactic radiosurgery (SRS). Methods: We systematically searched the PubMed, Embase, Cochrane, Web of Science, and Clinical Trials.gov databases for articles published between February 1, 1991, and April 11, 2022, with no language restrictions. We included studies involving patients with BMs receiving SRS; the included patients were required to have definite pathology of a primary tumor and complete imaging data (pre- and post-SRS). We excluded the articles that included patients who had undergone previous surgery and those that did not include regular follow-up or corresponding MRI scans. Results: We identified 2,162 studies, of which 26 were included in our analysis, involving a total of 1,362 participants. All 26 studies explored the relevant MRI parameters to predict the prognosis of patients with BMs who received SRS. The outcomes were generalized according to the relationships between the anatomical/morphological, microstructural, vascular, and metabolic changes and SRS. Generally, with traditional MRI, there are several quantitative prognostic models based on preradiosurgical radiomics that predict the outcome of SRS treatment in local BM control. With the implementation of advanced MRI, the relative apparent diffusion coefficient (ADC), perfusion fraction (f), relative cerebral blood volume (rCBV), relative regional cerebral blood flow (rrCBF), interstitial fluid pressure (IFP), quadratic of time-dependent leakage (Ktrans 2), extracellular extravascular volume (ve), choline/creatine (Cho/Cr), nuclear Overhauser effect (NOE) peak, and intraextracellular water exchange rate constant (kIE ) were confirmed to be indicative of the therapeutic effect of SRS for BMs. Conclusions: Quantitative MRI biomarkers extracted from traditional or advanced MRI at different time points, which can represent the anatomical/morphological, microstructural, vascular, and metabolic changes, respectively, have been proposed as promising markers for the early prediction of SRS response in those with BMs. There are some limitations in this review, including the risk of selection bias, the limited number of study objects, the incomparability of the total data, and the subjectivity of the review process.

Real-world analysis of first-line afatinib in patients with EGFR-mutant non-small cell lung cancer and brain metastasis: survival and prognostic factors.

Background: Overall survival (OS) in patients with non-small cell lung cancer (NSCLC) and brain metastases (BMs) is poor. We aimed to identify prognostic factors and ascertain treatment outcomes of first-line afatinib for patients with epidermal growth factor receptor (EGFR)-mutant NSCLC with BM in a real-world setting. Methods: This retrospective observational study reviewed electronic records of patients with EGFR-mutant NSCLC who received first-line afatinib treatment between October 2014 and October 2019 in 16 hospitals across South Korea. The Kaplan-Meier method estimated time on treatment (TOT) and OS; multivariate analyses were performed using Cox proportional hazards (PH) models. Results: Among 703 patients who received first-line afatinib, 262 (37.3%) had baseline BM. Of 441 patients without baseline BM, 92 (20.9%) developed central nervous system (CNS) failure. Compared with patients without CNS failure, those with CNS failure during afatinib treatment were younger (P=0.012), had a higher Eastern Cooperative Oncology Group (ECOG) performance status (PS) (P<0.001), increased metastatic site involvement (P<0.001), advanced stage disease (P<0.001), with liver metastasis (P=0.008) and/or bone metastasis (P<0.001) at baseline. Cumulative incidence of CNS failure in years 1, 2 and 3 was 10.1%, 21.5% and 30.0%, respectively. In multivariate analysis, cumulative incidence was significantly higher in patients with ECOG PS ≥2 (P<0.001), uncommon EGFR mutations (P=0.001), and no baseline pleural metastasis (P=0.017). Median TOT was 16.0 months (95% CI: 14.8-17.2) and, in patients with CNS failure, without CNS failure, and with baseline BM was 12.2, 18.9, and 14.1 months, respectively (P<0.001). Median OS was 52.9 months (95% CI: 45.4-60.3) and, in patients with CNS failure, without CNS failure, and with baseline BM was 29.1, 67.3 and 48.5 months, respectively (P<0.001). Conclusions: First-line afatinib in the real-world setting showed clinically meaningful effectiveness in patients with EGFR-mutant NSCLC and BM. CNS failure was a poor prognostic factor for TOT and OS correlating with younger age, poor ECOG PS, higher metastatic number, advanced disease stage, uncommon EGFR mutations, and baseline liver and/or bone metastases.

Whole brain atlas-based diffusion kurtosis imaging parameters for the evaluation of multiple cognitive-related brain microstructure injuries after radiotherapy in lung cancer patients with brain metastasis.

Background: Whole brain radiation therapy (WBRT) can cause cognitive dysfunctions in lung cancer patients with brain metastasis (BM). Diffusion kurtosis imaging (DKI) can detect brain microstructural alterations sensitivly. We aimed to identify the potential of DKI parameters for early radiation-induced brain injury and investigate the association between microstructure changes and neurocognitive function (NCF) decline. Methods: Lung cancer patients with BM (n=35) who underwent WBRT in a single center in Zhejiang, China, were consecutively and prospectively enrolled between June 24th, 2020 and December 22nd, 2021, and the median follow-up time was 6.0 months (3.6-6.6 months). DKI and T1-weighted (T1W) MRI scans were acquired prior to and following WBRT. Diffusivity-based (mean diffusivity, MD; fractional anisotropy, FA) and kurtosis-based (mean kurtosis, MK; axial kurtosis, AK) parameters were calculated within the automated anatomical labeling (AAL) atlas-based regions. Reliable change indices practice effects (RCI-PE) scores of the Mini-Mental State Examination (MMSE) were calculated to determine significant neurocognitive decline by a one-sample t-test from baseline to 2-6 months post-WBRT. To assess the subacute induced effects within the whole brain, percentage changes of DKI parameters were evaluated at 170 atlas-based regions by a one-sample t-test. Linear regression analyses were used to evaluate the association between DKI parameter changes and RCI-PE scores. Results: Finally, the study included 19 patients in the longitudinal follow-up. RCI-PE scores declined at 2-6 months post-WBRT (mean RCI-PE =-0.842, 95% CI, -0.376 to -1.310; P=0.002). With the atlas-based analysis of subacute effects after post-WBRT, a total of 28 regions changed in at least one diffusion parameter, revealing region-wise microstructural alterations in the brain. Significant correlations of at least one diffusion parameters with RCI-PEs were observed in 9 regions, such as the right orbital part of the inferior frontal gyrus [right IFGorb, r(AK) =0.47, P=0.03] and left middle temporal gyrus [left MTG, r(MK) =-0.49, P=0.03]. Conclusions: DKI parameters can be used to detect early microstructure changes and represent important imaging predictors for cognitive decline. The reported 9 regions are more particularly vulnerable to neurocognitive radiation-induced impairment for lung cancer patients with BM, representing potential dose-avoidance targets for cognitive function preservation.

Identification of distinct tumor cell patterns with single-cell RNA sequencing integrating primary lung adenocarcinoma and brain metastasis tumor.

Background: Lung adenocarcinoma (LUAD) is the most common form of lung cancer and is often accompanied by brain metastasis (BM). The heterogeneity of the tumor renders all current conventional treatments less effective. This study aims to dissect tumor cell heterogeneity and identify potential therapeutic targets. Methods: We conducted single-cell RNA-sequencing (scRNA-seq) in 8 patients with treatment-naïve LUAD BM and included scRNA-seq data of 10 primary LUAD samples and their matched adjacent normal tissue from GSE131907 to determine the tumor cell heterogeneity. Results: Our analyses revealed tumor cells derived from brain metastases were more heterogeneous. Tumor cells from BM harbored significantly more copy number variants (CNVs), and cells of magnoid subtype were the critical source of malignant cells both in BM and the primary lung tumor. Pseudo-time trajectory analysis revealed that malignant cells had upregulated genes enriched for cell cycle and cell division. Integrated analysis of tumor cells revealed 2 distinct malignant cell clusters (cluster 4 and cluster 6) and their marker genes. The signatures identified in the single-cell profile had prognostic value in the bulk tumor profiles. Moreover, the signature of cluster 4 had significant prognostic value in predicting patients surviving longer than 3.5 years, while the signature of cluster 6 showed better predictive ability within 1 year. Magnoid-type cells are most likely to develop into the riskiest cell type and potentially promote tumor progression. Conclusions: scRNA profiling that integrates LUAD BM and primary LUAD can provide information on those malignant cells with BM potential, offering additional prognostic information at cellular level, and may serve as a foundational resource for further tumor cell dissection and therapeutic target exploration.

Development and validation of nomograms to predict early death in non-small cell lung cancer patients with brain metastasis: a retrospective study in the SEER database.

Background: Throughout the course of non-small cell lung cancer (NSCLC), a lot of patients would develop brain metastasis (BM) associated with the poor prognosis and high rate of mortality. However, there have been few models to predict early death (ED) from NSCLC patients with BM. We aimed to develop nomograms to predict ED in NSCLC patients with BM. Methods: The NSCLC patients with BM between 2010 and 2015 were selected from the Surveillance, Epidemiology, and End Result (SEER) database. Our inclusion criteria were as follows: (I) patients were pathologically diagnosed as NSCLC; (II) patients who suffered from BM. The patients were randomly divided into 2 cohorts at the ratio of 7:3, for training and validation cohorts, respectively. The univariate and multivariate logistic regression methods were managed to identify risk factors for ED in NSCLC patients with BM. Two nomograms were established and validated by calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA). The follow-up data included survival months, causes of death, vital status. Death that occurred within 3 months of initial diagnosis is defined as ED and the endpoints were all-cause ED and cancer-specific ED. Results: A total of 4,920 NSCLC patients with BM were included and randomly divided into 2 cohorts (7:3), including the training (n=3,444) and validation (n=1,476) cohorts. The independent prognostic factors for all-cause ED and cancer-specific ED included age, sex, race, tumor size, histology, T stage, N stage, grade, surgical operation, radiotherapy, chemotherapy, bone metastasis, and liver metastasis. All these variables were used to establish the nomograms. In the nomograms of all-cause and cancer-specific ED, the areas under the ROC curves were 0.813 (95% CI: 0.799-0.837) and 0.808 (95% CI: 0.791-0.830) for the training dataset as well as 0.835 (95% CI: 0.805-0.862) and 0.824 (95% CI: 0.790-0.849) for the validation dataset, respectively. Besides, the calibration curves proved that the predicted ED was consistent with the actual value. DCA suggested a good clinical application. Conclusions: The nomograms can be used to predict the specific probability of a patient's death, which aids in treatment decisions and focused care, as well as in physician-patient communication.

Identification of key genes in HER2-positive breast cancer with brain metastasis via bioinformatics methods.

Background: Brain metastasis (BM) represents one of the most common advanced disease states in breast cancer (BC), especially in human epidermal growth factor receptor 2 (HER2)-positive BC, and is associated with poor survival outcomes. Methods: In this study, in-depth analysis of the microarray data from the GSE43837 dataset with 19 BM samples of HER2-positive BC patients and 19 HER2-positive nonmetastatic primary BC samples was conducted. The differentially expressed genes (DEGs) between BM and primary BC samples were identified and function enrichment analysis of the DEGs was conducted to identify potential biological functions. The hub genes were identified by constructing the protein-protein interaction (PPI) network using STRING and Cytoscape. UALCAN and Kaplan-Meier plotter online tools were used to verify the clinical roles of the hub DEGs in HER2-positive BC with BM (BCBM). Results: A total of 1,056 DEGs including 767 downregulated and 289 upregulated genes were identified by comparing the microarray data of the HER2-positive BM and primary BC samples. Functional enrichment analysis demonstrated that the DEGs were mainly enriched in pathways related to extracellular matrix (ECM) organization, cell adhesion, and collagen fibril organization. PPI network analysis identified 14 hub genes. Among these, CD44, COL1A2, MMP14, POSTN, and SOX9 were associated with the survival outcomes of HER2-positive patients. Conclusions: In summary, 5 BM-specific hub genes were identified in the study; those are potential prognostic biomarkers and therapeutic targets for HER2-positive BCBM patients. However, further investigations are necessary to unravel the mechanisms by which these 5 hub genes regulate BM in HER2-positive BC.

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.

Therapeutic strategies for HER2-positive breast cancer with central nervous system involvement: a literature review and future perspectives.

Background and Objective: Brain metastases (BMs) are present in approximately 55% of patients with HER2-positive breast cancer (HER2+ BC). The introduction of anti-HER2 agents has radically changed the prognosis of these patients by prolonging overall survival. Methods: In this review, we describe the biology of central nervous system (CNS) spreading in patients with HER2+ BC. We also provide a literature review of current treatment strategies of brain metastatic BC, focusing on HER2+ disease, and future perspectives. Key Content and Findings: Treatment of symptomatic BMs includes traditionally neurosurgery and/or radiotherapy, depending on the number of metastases, performance status and systemic disease control. Local treatments, such as surgical excision of BM and stereotactic radiosurgery (SRS), when feasible, are preferred over whole-brain radiotherapy, because of related cognitive impairment. These treatments can lead to a local control of the disease, however, systemic relapses can affect the prognosis of these patients. Recently, new anti-HER2 agents have demonstrated to be effective on BMs, thereby leading to improved survival outcomes with an acceptable quality of life. Despite the clinical benefit of these approaches, BMs still represent a cause of death and effective therapeutic strategies are needed. Conclusions: Different targeted agents have demonstrated significant efficacy with tolerable safety profiles in HER2+ BC patients with BM, and have already been approved for clinical use in this setting. A better understanding of the molecular mechanisms underlying the onset of BMs could suggest novel targeted approaches in order to prevent CNS localization or delay progression to CNS in HER-2 metastatic patients.

Resection of supratentorial brain metastases with intraoperative radiotherapy. Is it safe? Analysis and experiences of a single center cohort.

Introduction: Intraoperative Radiotherapy (ioRT) is an emerging treatment option in oncologic surgery for various diseases including intraaxial brain lesions to improve surgical outcome and accelerate the adjuvant oncologic therapy. Despite its use in glioma surgery, the application and data regarding ioRT in the treatment of brain metastases (BMs) is sparse. Here were report the largest series of supratentorial BMs treated with resection and ioRT according to functional outcome and adverse events. Methods: We performed a retrospective chart review analysis of patients undergoing surgery for BMs following an interdisciplinary tumor board decision in every case with ioRT at our institution. Patient properties, functional status (Karnofsky Performance Score/KPS) before and after surgery as well as oncologic (disease, recursive partitioning analysis, lesion size) and operative parameters were analyzed until hospital discharge. Adverse events (AE) were recorded until 30 days after surgery and rated according to the Clavien Dindo Grading (CDG) scale. Results: 70 patients (40 female) with various oncologic diseases were identified and analyzed. Six underwent prior RT. Mean age was 66 ± 11 years. Preoperative median KPS was 80% with a mean BM volume of 3.2 ± 1.2 cm3. Nine patients (13%) experienced in total 14 AEs, including 2 cases (3%) of postoperative death (CDG5) and 2 with new postoperative epilepsy necessitating additional pharmacotreatment (CDG2). Five patients suffered from new neurologic deficit (CDG1) not needing further surgical or medical treatment. After surgery, the neurological status in 7 patients (10%) deteriorated while it improved in 21 cases (30%). Patients experiencing AEs had longer hospitalization and poorer postoperative KPS mdn. 90 vs. 80%. There was no statistically significant deterioration of the functional status during the immediate postoperative course in the whole patient cohort. Conclusion: Surgery for supratentorial BMs with ioRT seems safe and feasible. Further studies on the benefit regarding oncologic outcome need to be performed.

Micro-ribonucleic acids (miRNAs) and a proteomic profile in lung adenocarcinoma cases with brain metastasis.

Background: Brain metastasis (BM) is the main cause of death of individuals with lung adenocarcinoma (LAC). Biomarkers with high sensitivity and specificity for the early detection and treatment of BM of LAC urgently need to be identified. In this study, we analyzed the pathogenesis of LAC-induced BM by detecting micro-ribonucleic acid (miRNA) and proteome expression differences between primary LAC lesion and BM tissue specimens to identify biomarkers of LAC-associated BM and develop potential therapeutic targets. Methods: The miRNA and protein profiles of non-metastatic primary LAC and BM cases were examined to further explore the mechanism of BM. The roles and interactions of differential miRNAs and proteins were subject to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The interactions of differential miRNAs and proteins were analyzed by R software and depicted using Cytoscape. Results: Compared to the LAC tissue specimens, 16 and 4 miRNAs showed increased and reduced levels, respectively, in the BM tissue specimens, and 53 proteins were upregulated, and 35 proteins were downregulated. The enrichment pathway analysis showed the nuclear factor kappa B (NF-κB) signaling and the primary immunodeficiency pathways played important roles in the pathogenetic mechanisms of BM in LAC. Conclusions: This study extended understandings of the regulatory network of miRNAs and proteins and provided novel insights into the pathogenic mechanisms of BM in LAC at the miRNA and protein levels.