Multidisciplinary management of brain metastases

Brain Metastases in Sarcomas: A Multicenter Retrospective Cohort Study

PURPOSE

Brain metastases (BM) in sarcomas occur rarely and are associated with poor prognosis. This study is a large retrospective cohort describing the demographic and clinical characteristics of these patients, treatment strategies, and survival outcomes.

METHODS

In total, 81 patients with BM from sarcomas were identified across five sarcoma centers. Demographic data, clinical presentation, and treatment modalities were analyzed.

RESULTS

The most common histologies were leiomyosarcoma (12.3%) and undifferentiated pleomorphic sarcoma (12.3%). The median time from sarcoma diagnosis to brain metastases was 1.9 years. Upon presentation, 88.9% of patients with BM from sarcomas were symptomatic with the most common presenting symptom being focal neurological deficits (37.9%) and headaches (22.1%). Higher-grade sarcomas were more likely to metastasize and were usually preceded by metastases to other sites, most commonly the lungs. One-year overall survival was 31% from initial sarcoma diagnosis, and the median time from diagnosis of BM until death was 6.0 months. For treatment, 60 (74.1%) patients had radiation, 39 (48.1%) patients had systemic therapy, and 29 (35.8%) patients had surgery. In a multivariate analysis, surgery (HR 0.30) and chemotherapy (HR 0.23) were found to be significantly correlated with improved survival outcomes. Although radiation as a whole was not found to significantly correlate with survival, improved outcomes were seen with stereotactic radiosurgery (SRS, mOS 11.6 mo) as opposed to whole-brain radiation therapy (WBRT, mOS 8.3 mo). Additionally, patients with leptomeningeal disease were significantly less likely to survive more than one year compared to patients with brain metastases only.

CONCLUSIONS

Our findings identify that patients with metastatic sarcoma to the brain have poor prognoses, often have concurrent metastasis, and have a median survival of only 6 months. Additionally, our study found that leptomeningeal metastases is a rare presentation with poor survival outcomes. There are various treatment modalities for sarcomas with BM; however, there are no guidelines, unlike in other malignancies. Further research is necessary to evaluate the role of therapeutic measures in terms of type, timing, and outcomes.

Optimizing Drug Delivery to the Brain for Breast Metastasis: A Novel Method for Tumor Targeting

INTRODUCTION

Brain metastases are difficult to treat due to the blood-brain barrier limiting the delivery of therapeutic agents to the brain effectively. Intraventricular drug delivery has not been well studied for intra-axial pathologies. However, our prior work demonstrated that intraventricular drug delivery in a hyperosmolar vehicle showed preferential accumulation of drug within breast cancer tissue compared to surrounding brain parenchyma. The focus of this study was to explore the molecular parameters of intraventricular drug administration that may optimize drug delivery to intra-axial brain metastases. Our hypothesis was that a low molecular weight drug with a high osmolarity solution would increase drug delivery to tumor tissue.

METHODS

We used an intracerebral breast cancer tumor model in adult female nude rats divided into six experimental groups. We examined three iron-labeled dextran molecules (3 kD, 5 kD, and 10 kD) in 337 mOsm/L solution and three different osmolarities of delivery solution (307, 353, and 368 mOsm/L) with 10 kD dextran. 7T magnetic resonance imaging (MRI) was used to analyze dextran distribution at different time points. All animals were sacrificed after two hours, and the quantity of dextran particles was determined by histopathology.

RESULTS

Breast cancer tumor cells were successfully implanted in all rats. The MRI quantification of dextran concentration was well corroborated by histopathology. Varying the molecular size of dextran resulted in the smallest molecule reaching peak levels in tumor tissue earlier than the larger molecules, but the larger molecules remained concentrated in tumor tissue for a longer time. Varying the osmolarity of the delivery solution resulted in the preferential accumulation of 10 kD dextran in tumor tissue except for when dextran was delivered in 368 mOsm/L solution where no preferential distribution was seen.

CONCLUSION

Hyperosmolar intraventricular delivery of chemotherapeutic drugs could be effective in preferentially delivering drugs to abnormal tumor tissues.

MicroRNA-522-3p promotes brain metastasis in non-small cell lung cancer by targeting Tensin 1 and modulating blood-brain barrier permeability

Brain metastases account for more than 50 % of intracranial central nervous system tumors. The blood-brain barrier (BBB) is mainly composed of endothelial cells, which exhibit low endocytosis and high efflux pumps. Although they are connected by continuous tight junctions and serve as a protective insulation, the BBB does not prevent the development of brain metastases from non-small cell lung cancer (NSCLC). Improving understanding on the mechanisms underlying the development of brain metastasis and the differential molecular characteristics relative to the primary tumor are therefore key in the treatment of brain metastases. This study evaluated the differential expression of miR-522-3p in NSCLC and brain metastases using the Gene Expression Omnibus database. NSCLC brain metastasis model was constructed to screen for cell lines that demonstrated high potential for brain metastasis; We also observed differential expression of miRNA-522-3p in the paraffin-embedded specimens of non-small cell lung cancer and brain metastases from our hospital. The molecular biological functions of miRNA-522-3p were verified using 5-ethynyl-2'-deoxyuridine (EdU) proliferation assay and Transwell invasion assays. RNA-seq was employed to identify downstream target proteins, and the dual-luciferase reporter assay confirmed Tensin 1 (TNS1), a protein that links the actin cytoskeleton to the extracellular matrix, as the downstream regulatory target protein. In vitro blood-brain barrier models and co-culture models were constructed to further identify the role of miRNA-522-3p and TNS1; the expression of BBB-related proteins (ZO-1 and OLCN) was also identified. In vivo experiments were performed to verify the effects of miRNA-522-3p on the time and incidence of NSCLC brain metastasis. The results showed significantly high expression in GSE51666; consistent results were obtained in brain metastasis cells and paraffin samples. RNA-seq combined with miRNA target protein prediction demonstrated TNS1 to be directly downstream of miR-522-3p and to be associated with cell proliferation and invasion. By regulating ZO-1 and OCLN expression, mi-522-3p/TNS1 may increase tumor cell penetration through the BBB while decreasing its permeability. In vivo, miR-522-3p was further demonstrated to significantly promote the formation of brain metastases. miR-522-3p/TNS1 can affect BBB permeability and encourage the growth of brain metastases by modifying the BBB TJ proteins. This axis offers new therapeutic targets for the prevention of brain metastasis.

Individualized trajectories in postradiotherapy neurocognitive functioning of patients with brain metastases

Background

The increasing incidence of brain metastases (BMs) and improved survival rates underscore the necessity to investigate the effects of treatments on individuals. The aim of this study was to evaluate the individual trajectories of subjective and objective cognitive performance after radiotherapy in patients with BMs.

Methods

The study population consisted of adult patients with BMs referred for radiotherapy. A semi-structured interview and comprehensive neurocognitive assessment (NCA) were used to assess both subjective and objective cognitive performance before, 3 months and ≥ 11 months after radiotherapy. Reliable change indices were used to identify individual, clinically meaningful changes.

Results

Thirty-six patients completed the 3-month follow-up, and 14 patients completed the ≥ 11-months follow-up. Depending on the domain, subjective cognitive decline was reported by 11-22% of patients. In total, 50% of patients reported subjective decline in at least one cognitive domain. Intracranial progression 3 months postradiotherapy was a risk-factor for self-reported deterioration (P = .031). Objective changes were observed across all domains, with a particular vulnerability for decline in memory at 3 months postradiotherapy. The majority of patients (81%) experienced both a deterioration as well as improvement (eg, mixed response) in objective cognitive functioning. Results were similar for the long-term follow-up (3 to ≥11 months). No risk factors for objective cognitive change 3 months postradiotherapy were identified.

Conclusions

Our study revealed that the majority of patients with BMs will show a mixed cognitive response following radiotherapy, reflecting the complex impact. This underscores the importance of patient-tailored NCAs 3 months postradiotherapy to guide optimal rehabilitation strategies.

Does 5-ALA Fluorescence Microscopy Improve Complete Resectability in Cerebral/Cerebellar Metastatic Surgery? A Retrospective Data Analysis from a Cranial Center

(1) Background: In this study, the intraoperative fluorescence behavior of brain metastases after the administration of 5-aminolevulinic acid (5-ALA) was analyzed. The aim was to investigate whether the resection of brain metastases using 5-ALA fluorescence also leads to a more complete resections and thus to a prolongation of survival; (2) Methods: The following variables have been considered: age, sex, number of metastases, localization, involvement of eloquent area, correlation between fluorescence and primary tumor/subtype, resection, and survival time. The influence on the degree of resection was determined with a control MRI within the first three postoperative days; (3) Results: Brain metastases fluoresced in 57.5% of cases. The highest fluorescence rates of 73.3% were found in breast carcinoma metastases and the histologic subtype adenocarcinoma (68.1%). No correlation between fluorescence behavior and localization, primary tumor, or histological subtype was found. Complete resection was detected in 82.5%, of which 56.1% were fluorescence positive. There was a trend towards improved resectability (increase of 12.1%) and a significantly longer survival time (p = 0.009) in the fluorescence-positive group; (4) Conclusions: 5-ALA-assisted extirpation leads to a more complete resection and longer survival and can therefore represent a low-risk addition to modern surgery for brain metastases.

Simultaneous targeting of peripheral and brain tumors with a therapeutic nanoparticle to disrupt metabolic adaptability at both sites

Brain metastasis of advanced breast cancer often results in deleterious consequences. Metastases to the brain lead to significant challenges in treatment options, as the blood-brain barrier (BBB) prevents conventional therapy. Thus, we hypothesized that creation of a nanoparticle (NP) that distributes to both primary tumor site and across the BBB for secondary brain tumor can be extremely beneficial. Here, we report a simple targeting strategy to attack both the primary breast and secondary brain tumors utilizing a single NP platform. The nature of these mitochondrion-targeted, BBB-penetrating NPs allow for simultaneous targeting and drug delivery to the hyperpolarized mitochondrial membrane of the extracranial primary tumor site in addition to tumors at the brain. By utilizing a combination of such dual anatomical distributing NPs loaded with therapeutics, we demonstrate a proof-of-concept idea to combat the increased metabolic plasticity of brain metastases by lowering two major energy sources, oxidative phosphorylation (OXPHOS) and glycolysis. By utilizing complementary studies and genomic analyses, we demonstrate the utility of a chemotherapeutic prodrug to decrease OXPHOS and glycolysis by pairing with a NP loaded with pyruvate dehydrogenase kinase 1 inhibitor. Decreasing glycolysis aims to combat the metabolic flexibility of both primary and secondary tumors for therapeutic outcome. We also address the in vivo safety parameters by addressing peripheral neuropathy and neurobehavior outcomes. Our results also demonstrate that this combination therapeutic approach utilizes mitochondrial genome targeting strategy to overcome DNA repair-based chemoresistance mechanisms.

Genetic Silencing of AKT Induces Melanoma Cell Death via mTOR Suppression

Aberrant activation of the PI3K-AKT pathway is common in many cancers, including melanoma, and AKT1, 2 and 3 (AKT1-3) are bona fide oncoprotein kinases with well-validated downstream effectors. However, efforts to pharmacologically inhibit AKT have proven to be largely ineffective. In this study, we observed paradoxical effects following either pharmacologic or genetic inhibition of AKT1-3 in melanoma cells. Although pharmacological inhibition was without effect, genetic silencing of all three AKT paralogs significantly induced melanoma cell death through effects on mTOR. This phenotype was rescued by exogenous AKT1 expression in a kinase-dependent manner. Pharmacological inhibition of PI3K and mTOR with a novel dual inhibitor effectively suppressed melanoma cell proliferation in vitro and inhibited tumor growth in vivo. Furthermore, this single-agent-targeted therapy was well-tolerated in vivo and was effective against MAPK inhibitor-resistant patient-derived melanoma xenografts. These results suggest that inhibition of PI3K and mTOR with this novel dual inhibitor may represent a promising therapeutic strategy in this disease in both the first-line and MAPK inhibitor-resistant setting.

Hippocampal sparing in whole-brain radiotherapy for brain metastases: controversy, technology and the future

Whole-brain radiotherapy (WBRT) plays an irreplaceable role in the treatment of brain metastases (BMs), but cognitive decline after WBRT seriously affects patients' quality of life. The development of cognitive dysfunction is closely related to hippocampal injury, but standardized criteria for predicting hippocampal injury and dose limits for hippocampal protection have not yet been developed. This review systematically reviews the clinical efficacy of hippocampal avoidance - WBRT (HA-WBRT), the controversy over dose limits, common methods and characteristics of hippocampal imaging and segmentation, differences in hippocampal protection by common radiotherapy (RT) techniques, and the application of artificial intelligence (AI) and radiomic techniques for hippocampal protection. In the future, the application of new techniques and methods can improve the consistency of hippocampal dose limit determination and the prediction of the occurrence of cognitive dysfunction in WBRT patients, avoiding the occurrence of cognitive dysfunction in patients and thus benefiting more patients with BMs.

Efficacy of apatinib+radiotherapy vs radiotherapy alone in patients with advanced multiline therapy failure for non small cell lung cancer with brain metastasis

OBJECTIVE

Lung cancer is the leading cause of cancer-associated mortality worldwide. Central nervous system (CNS) metastasis is a prevalent and serious complication. The most common treatment for brain metastasis (BM) is still radiation therapy (RT). An increasing number of drugs have been shown to have intracranial activity or to sensitize tumours to radiotherapy.

METHODS

Consecutive advanced multiline therapy failure in patients with non-small-cell lung cancer (NSCLC) with BM at the authors' hospital were retrospectively reviewed. Eligible patients were divided into two groups: Apatinib+RT group and RT group. Intracranial progression-free survival (PFS) and overall survival (OS) were analysed using the Kaplan-Meier method.

RESULTS

The median intracranial PFS for the RT group and Apatinib+RT group was 5.83 months and 11.81 months (p = 0.034). The median OS for the RT group and Apatinib+RT group was 9.02 months and 13.62 months (p = 0.311). The Apatinib+RT group had a better intracranial PFS, but there were no significant differences between the two arms in OS. The Apatinib+RT group had significantly reduced symptoms caused by BM.

CONCLUSION

RT combined with apatinib could help to control intracranial metastases. The Apatinib+RT group had significantly reduced symptoms caused by BM and improved quality of life for patients, the safety of the two treatments was similar.

ADVANCES IN KNOWLEDGE

Here, we propose that RT combined with apatinib can significantly relieve brain symptoms and tolerate side-effects without affecting OS in patients with BM following failure of multiline therapy for NSCLC. Of course, this paper is a retrospective origin study, and more powerful evidence is needed to demonstrate.

Evaluating Physiological MRI Parameters in Patients with Brain Metastases Undergoing Stereotactic Radiosurgery-A Preliminary Analysis and Case Report

Brain metastases occur in ten to thirty percent of the adult cancer population. Treatment consists of different (palliative) options, including stereotactic radiosurgery (SRS). Sensitive MRI biomarkers are needed to better understand radiotherapy-related effects on cerebral physiology and the subsequent effects on neurocognitive functioning. In the current study, we used physiological imaging techniques to assess cerebral blood flow (CBF), oxygen extraction fraction (OEF), cerebral metabolic rate of oxygen (CMRO2) and cerebrovascular reactivity (CVR) before and three months after SRS in nine patients with brain metastases. The results showed improvement in OEF, CBF and CMRO2 within brain tissue that recovered from edema (all p ≤ 0.04), while CVR remained impacted. We observed a global post-radiotherapy increase in CBF in healthy-appearing brain tissue (p = 0.02). A repeated measures correlation analysis showed larger reductions within regions exposed to higher radiotherapy doses in CBF (rrm = -0.286, p < 0.001), CMRO2 (rrm = -0.254, p < 0.001), and CVR (rrm = -0.346, p < 0.001), but not in OEF (rrm = -0.004, p = 0.954). Case analyses illustrated the impact of brain metastases progression on the post-radiotherapy changes in both physiological MRI measures and cognitive performance. Our preliminary findings suggest no radiotherapy effects on physiological parameters occurred in healthy-appearing brain tissue within 3-months post-radiotherapy. Nevertheless, as radiotherapy can have late side effects, larger patient samples allowing meaningful grouping of patients and longer follow-ups are needed.

Efficacy of Stereotactic Radiosurgery as Single or Combined Therapy for Brain Metastasis: A Systematic Review and Meta-Analysis

To determine the efficacy of stereotactic radiosurgery (SRS) in treating patients with brain metastases (BMs), a network meta-analysis (NMA) of randomized controlled trials (RCTs) and a direct comparison of cohort studies were performed. Relevant literature regarding the effectiveness of SRS alone and in combination with whole-brain radiotherapy (WBRT) and surgery was retrieved using systematic database searches up to April 2019. The patterns of overall survival (OS), one-year OS, progression-free survival (PFS), one-year local brain control (LBC), one-year distant brain control (DBC), neurological death (ND), and complication rate were analyzed. A total of 18 RCTs and 37 cohorts were included in the meta-analysis. Our data revealed that SRS carried a better OS than SRS+WBRT (p= 0.048) and WBRT (p= 0.041). Also, SRS+WBRT demonstrated a significantly improved PFS, LBC, and DBC compared to WBRT alone and SRS alone. Finally, SRS achieved the same LBC as high as surgery, but intracranial relapse occurred considerably more frequently in the absence of WBRT. However, there were not any significant differences in ND and toxicities between SRS and other groups. Therefore, SRS alone may be a better alternative since increased patient survival may outweigh the increased risk of brain tumor recurrence associated with it.

The Economic Burden of Malignant Brain Tumors

Malignant brain tumors consist of primary malignant tumors and metastatic brain tumors. The global incidence and prevalence of CNS cancers are increasing, their mortality and morbidity are relatively higher than other cancers (e.g., bladder cancer), and the management of disease utilizes sophisticated and expensive diagnostic and therapeutic technology. Therefore, malignant brain tumors, both primary and metastatic, impose a significant economic burden on patients, their families, and healthcare systems all around the world. To the best of our knowledge, there is no comprehensive and global systematic review for examining the costs of brain tumors, though sporadic reports highlight the importance of the problem. Besides, each study takes place in a setting with different methods (e.g., different treatment methods) and costs to manage brain tumors; therefore, we are unable to compare the costs between countries. Nevertheless, the general patterns seem to suggest that, among all, gliomas and glioblastomas are the most financially burdensome types of malignant brain cancer. Finally, most of the available studies have examined the economic burden of all gliomas or only glioblastoma. Hence, we are left with a substantial gap in knowledge to understand the actual economic burden of metastatic brain tumors, and there is a need for further accurate and internationally comparable studies on the subject, particularly with a focus on indirect and intangible costs.

Neurocognitive functioning after Gamma Knife and LINAC stereotactic radiosurgery in patients with brain metastases

PURPOSE

Brain metastases (BM) themselves and treatment with stereotactic radiosurgery (SRS) can influence neurocognitive functioning. This prospective study aimed to assess neurocognitive decline in patients with BM after SRS.

METHODS

A neuropsychological test battery was assessed yielding ten test outcomes. Neurocognitive decline at 3 and 6 months post SRS was compared to measurement prior to Gamma Knife (GK) or linear accelerator (LINAC) SRS. Reliable change indices with correction for practice effects were calculated to determine the percentage of neurocognitive decline (defined as decline on ≥ 2 test outcomes). Risk factors of neurocognitive decline were analyzed with binary logistic regression.

RESULTS

Of 194 patients pre-SRS, 40 GK and 29 LINAC patients had data accessible at 6 months. Compared to baseline, 38% of GK patients declined at 3 months, and 23% declined at 6 months. GK patients declined on attention, executive functioning, verbal memory, and fine motor skill. Of LINAC patients, 10% declined at 3 months, and 24% at 6 months. LINAC patients declined on executive functioning, verbal memory, and fine motor skills. Risk factors of neurocognitive decline at 3 months were high age, low education level and type of SRS (GK or LINAC). At 6 months, high age was a risk factor. Karnofsky Performance Scale, BM volume, number of BM, tumor progression and neurocognitive impairment pre-SRS were no risk factors.

CONCLUSION

Neurocognitive decline occurs in a considerable proportion of patients with BM treated with GK or LINAC SRS. Overall, high age appears to be a risk factor for neurocognitive decline after SRS.

miR-596-3p suppresses brain metastasis of non-small cell lung cancer by modulating YAP1 and IL-8

Brain metastasis (BM) frequently occurs in advanced non-small cell lung cancer (NSCLC) and is associated with poor clinical prognosis. Due to the location of metastatic lesions, the surgical resection is limited and the chemotherapy is ineffective because of the existence of the blood brain barrier (BBB). Therefore, it is essential to enhance our understanding about the underlying mechanisms associated with brain metastasis in NSCLC. In the present study, we explored the RNA-Seq data of brain metastasis cells from the GEO database, and extracted RNA collected from primary NSCLC tumors as well as paired brain metastatic lesions followed by microRNA PCR array. Meanwhile, we improved the in vivo model and constructed a cancer stem cell-derived transplantation model of brain metastasis in mice. Our data indicated that the level of miR-596-3p is high in primary NSCLC tumors, but significantly downregulated in the brain metastatic lesion. The prediction target of microRNA suggested that miR-596-3p was considered to modulate two genes essential in the brain invasion process, YAP1 and IL-8 that restrain the invasion of cancer cells and permeability of BBB, respectively. Moreover, in vivo experiments suggested that our model mimics the clinical aspect of NSCLC and improves the success ratio of brain metastasis model. The results demonstrated that miR-596-3p significantly inhibited the capacity of NSCLC cells to metastasize to the brain. Furthermore, these finding elucidated that miR-596-3p exerts a critical role in brain metastasis of NSCLC by modulating the YAP1-IL8 network, and this miRNA axis may provide a potential therapeutic strategy for brain metastasis.

Evolution in endoscopic endonasal approach for the management of hypothalamic–pituitary region metastasis: A single-institution experience

Introduction

Endonasal endoscopic surgery has changed the treatment perspectives for different lesions of the hypothalamic–pituitary region. The metastases of the hypothalamic–pituitary region represent 0.4% of all intracranial metastatic tumors and account for only 1.8% of surgically managed pituitary lesions. The aim of tshis study is to describe a single-center institutional experience with 13 cases of hypothalamic–pituitary metastasis focused on presurgical workup, the evolution of the surgical technique, and postsurgical management according to our protocols, showing effects on progression-free and overall survival rates for this relatively uncommon location.

Material and Methods

We retrospectively reviewed the whole series of patients that received the endoscopic endonasal approach at the Division of Neurosurgery at the University of Naples “Federico II” undergoing surgery from January 1997 to December 2021. We identified 13 cases whose pathology reports revealed a metastatic lesion. Statistical analysis was performed to determine the Kaplan–Meier survival function and assess for log-rank differences in survival based on gender, surgical treatment, and postoperative therapy (p-value &lt; 0.02*).

Results

The pathology report disclosed lung adenocarcinoma (six cases, 46%), breast adenocarcinoma (two cases, 15.4%), clear cell renal carcinoma (one case, 7%), melanoma (one case, 7%), colorectal adenocarcinoma (one case, 7%), uterine cervix carcinoma (one case, 7%), and follicular thyroid carcinoma (one case, 7%). A standard endoscopic endonasal approach was performed in 10 patients (76.9%), while an extended endonasal procedure was performed in only three cases (23%). Biopsy was the surgical choice in five patients with infiltrative and invasive lesions and a poor performance status (38%), while in the cases where neurovascular decompression was necessary, a subtotal resection was achieved in five patients (38%) and partial resection in three patients (23%). Recovery of visual field defect was observed in six of seven patients with visual loss (85.7%), improvement of oculomotor nerve palsy occurred in four of seven patients with this defect (57.1%), while the impairment of oculomotor palsy was observed in three patients (42.9%). Visual function was stable in the other patients. The median progression-free survival and overall survival were 14 and 18 months, respectively. There were statistically significant differences in PFS and OS in patients who underwent adjuvant radiotherapy (p=0.019 is referred to OS and p=0.017 to PFS, respectively; p-value = 0.02).

Conclusions

The endoscopic endonasal approach is a viable approach for the management of hypothalamic–pituitary metastases as this surgery provides an adequate opportunity to obtain tissue sample and neurovascular decompression, both being crucial for continuing the integrated adjuvant therapy protocols.

ASCEND-7: Efficacy and Safety of Ceritinib Treatment in Patients with ALK-Positive Non-Small Cell Lung Cancer Metastatic to the Brain and/or Leptomeninges

PURPOSE

Central nervous system metastases are a prominent cause of morbidity and mortality in patients with ALK-positive (ALK+) non-small cell lung cancer (NSCLC). The phase II ASCEND-7 (NCT02336451) study was specifically designed to assess the efficacy and safety of the ALK inhibitor (ALKi) ceritinib in patients with ALK+ NSCLC metastatic to the brain and/or leptomeninges.

PATIENTS AND METHODS

Patients with active brain metastases were allocated to study arms 1 to 4 based on prior exposure to an ALKi and/or prior brain radiation (arm 1: prior radiotherapy/ALKi-pretreated; arm 2: no radiotherapy/ALKi-pretreated; arm 3: prior radiotherapy/ALKi-naïve; arm 4: no radiotherapy/ALKi-naïve). Arm 5 included patients with leptomeningeal carcinomatosis. Patients received ceritinib 750 mg once daily (fasted condition). Primary endpoint was investigator-assessed whole-body overall response rate (ORR) per RECIST v1.1. Secondary endpoints included disease control rate (DCR) and intracranial/extracranial responses.

RESULTS

Per investigator assessment, in arms 1 (n = 42), 2 (n = 40), 3 (n = 12), and 4 (n = 44), respectively: whole-body ORRs [95% confidence interval (CI)] were 35.7% (21.6-52.0), 30.0% (16.6-46.5), 50.0% (21.1-78.9), and 59.1% (43.2-73.7); whole-body DCR (95% CI): 66.7% (50.5-80.4), 82.5% (67.2-92.7), 66.7% (34.9-90.1), and 70.5% (54.8-83.2); intracranial ORRs (95% CI): 39.3% (21.5-59.4), 27.6% (12.7-47.2), 28.6% (3.7-71.0), and 51.5% (33.5-69.2). In arm 5 (n = 18), whole-body ORR was 16.7% (95% CI, 3.6-41.4) and DCR was 66.7% (95% CI, 41.0-86.7). Paired cerebrospinal fluid and plasma sampling revealed that ceritinib penetrated the human blood-brain barrier.

CONCLUSIONS

Ceritinib showed antitumor activity in patients with ALK+ NSCLC with active brain metastases and/or leptomeningeal disease, and could be considered in the management of intracranial disease. See related commentary by Murciano-Goroff et al., p. 2477.

Survival Benefit from Surgical Resection in Lung Cancer Patients with Brain Metastases: a Single-Center, Propensity-Matched Analysis Cohort Study

BACKGROUND

Brain metastases (BMs) are the most serious complication of lung cancer, affecting the prognosis of lung cancer patients, and pose distinct clinical challenges. This study was designed to explore the prognostic factors related to lung cancer BM and the value of surgical resection in BMs from lung cancer.

METHODS

A retrospective analysis was performed on 714 patients with lung cancer BMs screened between January 2010 and January 2018 at the Sun Yat-sen University Cancer Center. A 1:1 propensity score matching analysis was performed to reduce the potential bias between the surgery and the nonsurgery group. In both the raw and the propensity-score matched dataset, univariate and multivariate Cox proportional hazards regression analyses were used to evaluate risk factors for survival.

RESULTS

After matching, 258 patients (129 surgery, 129 no surgery) were analyzed. Multivariate analyses after propensity score matching demonstrated that surgical resection was an independent protective factor for overall survival (OS), and older age, lower Karnofsky Performance Scale (KPS) score, and extracranial metastases were independent risk factors for worse OS. Patients without extracranial metastases, without synchronous BM and with a single BM had a better prognosis.

CONCLUSIONS

The findings showed that surgical resection, age, KPS score, and extracranial metastases are independent prognostic factors for predicting the OS of patients with lung cancer BMs, and surgical resection for brain metastatic lesions could significantly improve the OS. However, only certain groups of patients with BMs can benefit from intracranial lesion resection, such as no extracranial metastases and metachronous metastases.

Modern possibilities of neurosurgical treatment of brain metastases

Despite significant progress in neuroimaging and introduction of new combined treatments for solid tumors, brain metastases are still adverse factor for overall survival. Brain metastases are diagnosed in 8-10% of patients and associated with extremely poor prognosis. These lesions result focal and general cerebral symptoms. Literature review highlights the current principles of surgical treatment of metastatic brain lesions in patients with solid tumors.

Brain metastases: increasingly precision medicine-a narrative review

Objective

To broadly review the modern management of brain metastases.

Background

Brain metastases are the commonest neurological manifestation of cancer and a major cause of morbidity in cancer patients. Brain metastases are increasing in frequency, as a result of longer life expectancy of cancer patients, more sensitive methods for brain metastasis detection and an ageing population. The proportional incidence of brain metastases according to cancer of origin, from greatest to least, is lung cancer, melanoma, renal, breast and colorectal cancers. Patients with lung cancer and melanoma are most likely to have brain metastases at diagnosis. Brain metastases cause a variety of symptoms, depending on their size and location, whether they cause mass effect and oedema, compression of the brain parenchyma, or focal neurological deficits. The major differential diagnoses of brain metastases include primary tumours and vascular/inflammatory lesions. Prognosis is dependent on the site, number and volume of lesions, the patients’ performance status, age and the activity and extent of extracranial disease.

Methods

English literature articles in PubMed from 1950 to June 2021 were reviewed. Article bibliographies provided further references.

Conclusions

Treatment of brain metastasis patients has moved from considering them as a homogenous population of patients, to individualised treatment. In those brain metastases patients of satisfactory performance status with a solitary lesion, especially one in a non-eloquent/accessible area causing significant mass effect and/or raised intracranial pressure or for whom the diagnosis is in doubt (histology needed), surgical resection is usually the treatment of choice. For multiple brain metastases, radiotherapy with or without systemic therapies are usually employed. For relatively fit patients with limited numbers of brain metastases (e.g., 4 or less), stereotactic radiosurgery is standard of care. Current clinical trials are testing the efficacy of stereotactic treatment alone for >4 brain metastases (although it is increasingly used for such patients in many centres) as well as integration of local therapies with targeted and immunological therapies in appropriately selected cases. In certain circumstances, cranial irradiation can be omitted.

Advances in radiotherapy for brain metastases

As novel systemic therapies yield improved survival in metastatic cancer patients, the frequency of brain metastases continues to increase. Over the years, management strategies have continued to evolve. Historically, stereotactic radiosurgery has been used as a boost to whole-brain radiotherapy (WBRT) but is increasingly being used as a replacement for WBRT. Given its capacity to treat both macro- and micro-metastases in the brain, WBRT has been an important management strategy for years, and recent research has identified technologic and pharmacologic approaches to delivering WBRT more safely. In this review, we outline the current landscape of radiotherapeutic treatment options and discuss approaches to integrating radiotherapy advances in the contemporary management of brain metastases.

Evolving Landscape of Long Non-coding RNAs in Cerebrospinal Fluid: A Key Role From Diagnosis to Therapy in Brain Tumors

Long non-coding RNAs (lncRNAs) are a type of non-coding RNAs that act as molecular fingerprints and modulators of many pathophysiological processes, particularly in cancer. Specifically, lncRNAs can be involved in the pathogenesis and progression of brain tumors, affecting stemness/differentiation, replication, invasion, survival, DNA damage response, and chromatin dynamics. Furthermore, the aberrations in the expressions of these transcripts can promote treatment resistance, leading to tumor recurrence. The development of next-generation sequencing technologies and the creation of lncRNA-specific microarrays have boosted the study of lncRNA etiology. Cerebrospinal fluid (CSF) directly mirrors the biological fluid of biochemical processes in the brain. It can be enriched for small molecules, peptides, or proteins released by the neurons of the central nervous system (CNS) or immune cells. Therefore, strategies that identify and target CSF lncRNAs may be attractive as early diagnostic and therapeutic options. In this review, we have reviewed the studies on CSF lncRNAs in the context of brain tumor pathogenesis and progression and discuss their potential as biomarkers and therapeutic targets.

Pituitary metastasis: From pathology to clinical and radiological considerations

PURPOSE

A review of the literature with respect to pituitary metastases (PM) with clinical and radiological considerations are summarized to facilitate clinical decision making in the management of PM METHODS: A review of literature associated with PM and tumour to tumour metastases in the English literature was reviewed and summarized RESULTS: Pituitary metastases account for 1.0-3.6% of all surgically treated pituitary lesions. Often identified in parallel with extensive disseminated disease, once diagnosed, the prognosis is generally poor, although survival is highly heterogeneous and dependent on the primary tumor histology. Within this anatomical region is also the observation of tumor-to-tumor metastases and collision tumours. Both the tumor macro- and microenvironment play central roles to the progression of disease with distinctive radiological features that may suggest a metastatic sellar lesion as opposed to a primary pituitary lesion. Surgical resection is the first line of therapy followed by adjuvant chemoradiotherapy and endocrinological evaluation for hormonal supplementation CONCLUSION: PMs are relatively rare but important oncological entities representing disseminated disease in the majority of cases. Careful consideration of the relevant clinical history and radiological features can aid the clinician differentiate between a metastatic lesion to the pituitary region and a primary pituitary tumor. While surgical resection is first line therapy, stereotactic radiosurgery in carefully selected patients is emerging as a viable alternative.

The Impact of Stereotactic or Whole Brain Radiotherapy on Neurocognitive Functioning in Adult Patients with Brain Metastases: A Systematic Review and Meta-Analysis

Background & Objectives: Radiotherapy is standard treatment for patients with brain metastases (BMs), although it may lead to radiation-induced cognitive impairment. This review explores the impact of whole-brain radiotherapy (WBRT) or stereotactic radiosurgery (SRS) on cognition.

METHODS

The PRISMA guidelines were used to identify articles on PubMed and EmBase reporting on objective assessment of cognition before, and at least once after radiotherapy, in adult patients with nonresected BMs.

RESULTS

Of the 867 records screened, twenty articles (14 unique studies) were included. WBRT lead to decline in cognitive performance, which stabilized or returned to baseline in patients with survival of at least 9-15 months. For SRS, a decline in cognitive performance was sometimes observed shortly after treatment, but the majority of patients returned to or remained at baseline until a year after treatment.

CONCLUSIONS

These findings suggest that after WBRT, patients can experience deterioration over a longer period of time. The cognitive side effects of SRS are transient. Therefore, this review advices to choose SRS as this will result in lowest risks for cognitive adverse side effects, irrespective of predicted survival. In an already cognitively vulnerable patient population with limited survival, this information can be used in communicating risks and aid in making educated decisions.

Delivering Antisense Oligonucleotides across the Blood-Brain Barrier by Tumor Cell-Derived Small Apoptotic Bodies

The blood-brain barrier (BBB) is the most restrictive and complicated barrier that keeps most biomolecules and drugs from the brain. An efficient brain delivery strategy is urgently needed for the treatment of brain diseases. Based on the studies of brain-targeting extracellular vesicles (EVs), the potential of using small apoptotic bodies (sABs) from brain metastatic cancer cells for brain-targeting drug delivery is explored. It is found that anti-TNF-α antisense oligonucleotide (ASO) combined with cationic konjac glucomannan (cKGM) can be successfully loaded into sABs via a transfection/apoptosis induction process and that the sABs generated by B16F10 cells have an extraordinarily high brain delivery efficiency. Further studies suggest that ASO-loaded sABs (sCABs) are transcytosed by b. End3 (brain microvascular endothelial cells, BMECs) to penetrate the BBB, which is mediated by CD44v6, and eventually taken up by microglial cells in the brain. In a Parkinson's disease (PD) mouse model, sCABs dramatically ameliorate PD symptoms via the anti-inflammatory effect of ASO. This study suggests that sABs from brain metastatic cancer cells are excellent carriers for brain-targeted delivery, as they have not only an extraordinary delivery efficiency but also a much higher scale-up production potential than other EVs.

BET inhibition increases βIII-tubulin expression and sensitizes metastatic breast cancer in the brain to vinorelbine

Metastases from primary breast cancer result in poor survival. βIII-tubulin (TUBB3) has been established as a therapeutic target for breast cancer metastases specifically to the brain. In this study, we conducted a systematic analysis to determine the regulation of TUBB3 expression in breast cancer metastases to the brain and strategically target these metastases using vinorelbine (VRB), a drug approved by the U.S. Food and Drug Administration (FDA). We found that human epidermal growth factor receptor 2 (HER2) signaling regulates TUBB3 expression in both trastuzumab-sensitive and trastuzumab-resistant neoplastic cells. We further discovered that bromodomain and extra-terminal domain (BET) inhibition increases TUBB3 expression, rendering neoplastic cells more susceptible to apoptosis by VRB. Orthotopic xenograft assays using two different breast cancer cell models revealed a reduction in tumor volume with BET inhibition and VRB treatment. In addition, in vivo studies using a model of multiple brain metastasis (BM) showed improved survival with the combination of radiation + BET inhibitor (iBET-762) + VRB (75% long-term survivors, P < 0.05). Using in silico analysis and BET inhibition, we found that the transcription factor myeloid zinc finger-1 (MZF-1) protein binds to the TUBB3 promoter. BET inhibition decreases MZF-1 expression and subsequently increases TUBB3 expression. Overexpression of MZF-1 decreases TUBB3 expression and reduces BM in vivo, whereas its knockdown increases TUBB3 expression in breast cancer cells. In summary, this study demonstrates a regulatory mechanism of TUBB3 and provides support for an application of BET inhibition to sensitize breast cancer metastases to VRB-mediated therapy.

WBRT for brain metastases from non-small cell lung cancer: for whom and when?-Contemporary point of view

The incidence of brain metastases (BM) is estimated between 20% and 40% of patients with solid cancer. The most common cause of this failure is lung cancer, and in locally advanced non-small cell lung cancer (NSCLC) BM represent a common site of relapse in 30-55% cases. The basic criteria of therapeutic decision-making are based on the significant prognostic factors which are components of prognostic scores. The standard approach to treatment of BM from NSCLC include whole brain radiotherapy (WBRT) which is used as adjuvant modality after local therapy (surgery or stereotactic radiosurgery) or as primary treatment and it remains the primary modality of treatment for patients with multiple metastases. WBRT is also used in combination with systemic therapy. The aim of presented review of literature is trying to answer which patients with BM from NSCLC should receive WBRT and when it could be omitted. There were presented the aspects of application of WBRT in relation to (I) choice between WBRT or the best supportive care and (II) employment of WBRT in combination with local treatment modalities [surgical resection or stereotactic radio-surgery (SRS)] and/or with systemic therapy. According to data from literature we concluded that the most important factor that needs to be considered when assessing the suitability of a patient for WBRT is the patient's prognosis based on the Lung-molGPA score. WBRT should be applied in treatment of multiple BM from lung cancer in patients with favourable prognosis and in in patients with presence of EML4-ALK translocation before therapy with crizotinib. Whereas WBRT could be omitted in patients with poor prognosis and after primary SRS.

At the Bench: Pre-clinical evidence for multiple functions of CXCR4 in cancer

Signaling through chemokine receptor, C-X-C chemokine receptor type 4 (CXCR4) regulates essential processes in normal physiology, including embryogenesis, tissue repair, angiogenesis, and trafficking of immune cells. Tumors co-opt many of these fundamental processes to directly stimulate proliferation, invasion, and metastasis of cancer cells. CXCR4 signaling contributes to critical functions of stromal cells in cancer, including angiogenesis and multiple cell types in the tumor immune environment. Studies in animal models of several different types of cancers consistently demonstrate essential functions of CXCR4 in tumor initiation, local invasion, and metastasis to lymph nodes and distant organs. Data from animal models support clinical observations showing that integrated effects of CXCR4 on cancer and stromal cells correlate with metastasis and overall poor prognosis in >20 different human malignancies. Small molecules, Abs, and peptidic agents have shown anticancer efficacy in animal models, sparking ongoing efforts at clinical translation for cancer therapy. Investigators also are developing companion CXCR4-targeted imaging agents with potential to stratify patients for CXCR4-targeted therapy and monitor treatment efficacy. Here, pre-clinical studies demonstrating functions of CXCR4 in cancer are reviewed.

Foundations of Neuro-Oncology: A Multidisciplinary Approach

Neuro-oncology is a branch of medicine focused on the diagnosis and treatment of primary and secondary tumors of the nervous system as well as the neurologic complications of cancer and cancer treatments. In practice, neuro-oncologists require an intimate knowledge of the neurologic presentation and management of central nervous system tumors, including gliomas, meningiomas, primary central nervous system lymphoma, metastases to the nervous system, and others. The mainstays of treatment for most nervous system tumors include surgical intervention, radiation therapy, and medical treatment with chemotherapy, immunotherapy, and/or targeted therapy. Interdisciplinary collaboration is thus critical to neuro-oncology. The prognosis for many central nervous system tumors, including gliomas and brain metastases, is often poor despite the advent of novel medical therapies. Efforts to develop more effective therapies are ongoing, and patient enrollment in clinical trials assessing the efficacy of new treatments is crucial to improve outcomes.

Effects of systemic therapy and local therapy on outcomes of 873 breast cancer patients with metastatic breast cancer to brain: MD Anderson Cancer Center experience

Outcomes of treatments for patients with breast cancer brain metastasis (BCBM) remain suboptimal, especially for systemic therapy. To evaluate the effectiveness of systemic and local therapy (surgery [S], stereotactic radiosurgery [SRS] and whole brain radiotherapy [WBRT]) in BCBM patients, we analyzed the data of 873 BCBM patients from 1999 to 2012. The median overall survival (OS) and time to progression in the brain (TTP-b) after diagnosis of brain metastases (BM) were 9.1 and 7.1 months, respectively. WBRT prolonged OS in patients with multiple BM (hazard ratio [HR], 0.68; 95% CI, 0.52-0.88; P = .004). SRS alone, and surgery or SRS followed by WBRT (S/SRS + WBRT), were equivalent in OS and TTP-b (median OS, 14.9 vs 17.2 months; median TTP-b, 8.2 vs 8.6 months). Continued chemotherapy prolonged OS (HR, 0.35; 95% CI, 0.30-0.41; P < .001) and TTP-b (HR, 0.48; 95% CI, 0.33-0.70; P < .001), however, with no advantage of capecitabine over other chemotherapy agents used (median OS, 11.8 vs 12.4 months; median TTP-b, 7.2 vs 7.4 months). Patients receiving trastuzumab at diagnosis of BM, continuation of anti-HER2 therapy increased OS (HR, 0.53; 95% CI, 0.34-0.83; P = .005) and TTP-b (HR, 0.41; 95% CI, 0.23-0.74; P = .003); no additional benefit was seen with switching over between trastuzumab and lapatinib (median OS, 18.4 vs 22.7 months; median TTP-b: 7.4 vs 8.7 months). In conclusion, SRS or S/SRS + WBRT were equivalent for patients' OS and local control. Continuation systemic chemotherapy including anti-HER2 therapy improved OS and TTP-b with no demonstrable advantage of capecitabine and lapatinib over other agents of physicians' choice was observed.

Neurosurgical Interactive Teaching Series: Multidisciplinary Educational Approach

OBJECTIVE

The goal of this manuscript is to investigate the effects of a multidisciplinary multinational web-based teaching conference on trainee education, research, and patient care.

METHODS

We present the structure, case selection, and presentation of our educational lectures. We retrospectively reviewed our database to gather data on the number of presentations, type of presentation, and the pathology diagnosis from November 11, 2016 until February 28, 2020. To investigate attendee satisfaction, we analyzed our yearly continuing medical education evaluation survey results to report the impact that this series may have had on our attendees. We assigned a numeric value to the answers, and the mean overall scores were compared through an analysis of variance. Further analysis on specific questions was performed with a Fisher exact test.

RESULTS

We have hosted 150 lectures, in which we have presented 208 neurosurgical cases corresponding to 133 general session, 59 pituitary, and 16 spine cases, as well as 28 distinct lectures by guest speakers from institutions across the globe. We received 61 responses to our yearly continuing medical education evaluations over the course of 3 years. On these evaluations, we have maintained an excellent overall rating from 2017-2019 (two-sided P > 0.05) and received significantly less suggestions to improve the series comparing 2017 with 2019 (two-sided, P= 0.04).

CONCLUSIONS

As the world of medicine is constantly changing, we are in need of developing new tools to enhance our ability to relay knowledge through accredited and validated methods onto physicians in training, such as the implementation of structured, multidisciplinary, case-based lectures as presented in this manuscript.

Lapatinib Plus Local Radiation Therapy for Brain Metastases From HER-2 Positive Breast Cancer Patients and Role of Trastuzumab: A Systematic Review and Meta-Analysis

Background

Intracranial activity of lapatinib has been demonstrated in several studies in patients with human epidermal growth factor receptor-2 positive breast cancers (HER-2+ BC). Stereotactic radiosurgery (SRS) has been increasingly used as the local therapy for brain metastases in breast cancer patients. Increased objective response rate was observed for lapatinib plus whole brain radiotherapy (WBRT) is such patients with high toxicity.

Objective

We seek to obtain clinical evidence of synergistic efficacy of lapatinib in combination with radiation therapy, in particular, SRS.

Materials and methods

We carried out a comprehensive research using the following databases: PubMed; Medline; EMBASE; Cochrane library. These databases were searched until 10 June 2020. PRISMA guidelines were followed step by step for carrying out this systematic review and meta-analysis. Review Manager v 5.4 software was used for statistical evaluation of data.

Results

Overall 6 studies with 843 HER-2 positive breast cancer patients (442 HER-2 amplified disease, 399 luminal B disease) were included in this systematic review and meta-analysis. A total 279 patients had received lapatinib in addition to HER-2 antibody (trastuzumab) plus/minus chemoradiotherapy, while 610 patients had received trastuzumab-based management or only chemoradiotherapy. Lapatinib-based management of BM was associated with significant increase in overall survival (HR 0.63 [0.52, 0.77], p < 0.00001). Combination of the two (trastuzumab plus lapatinib) was associated with increased survival advantage compared to each agent alone (0.55 [0.32, 0.92], p = 0.02). SRS in combination with lapatinib was associated with increased local control (HR 0.47 [0.33, 0.66], p = 0.0001). Ever use of lapatinib with SRS was associated an increased survival as reported in two studies (Shireen et al.: 27.3 vs. 19.5 months, p = 0.03; Kim et al.: 33.3 vs. 23.6 months, p = 0.009). Kim et al. also revealed significant increase in intracranial activity with concurrent lapatinib reporting 57% complete response compared to 38% (p < 0.001) and lower progressive disease rate of 11 vs. 19% (p < 0.001). Risk of radiation necrosis was decreased with lapatinib use.

Conclusions

Lapatinib has shown intracranial activity and yielded better survival for HER-2+ BC patients with BMs. SRS in combination with ever use of lapatinib had better local control and were associated with better survival. Radiation necrosis risk was reduced with the use of lapatinib.

Central Nervous System Cancers, Version 3.2020, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Central Nervous System (CNS) Cancers focus on management of adult CNS cancers ranging from noninvasive and surgically curable pilocytic astrocytomas to metastatic brain disease. The involvement of an interdisciplinary team, including neurosurgeons, radiation therapists, oncologists, neurologists, and neuroradiologists, is a key factor in the appropriate management of CNS cancers. Integrated histopathologic and molecular characterization of brain tumors such as gliomas should be standard practice. This article describes NCCN Guidelines recommendations for WHO grade I, II, III, and IV gliomas. Treatment of brain metastases, the most common intracranial tumors in adults, is also described.

Single-Isocenter Volumetric Modulated Arc Therapy (VMAT) Radiosurgery for Multiple Brain Metastases: Potential Loss of Target(s) Coverage Due to Isocenter Misalignment

Purpose A single-isocenter volumetric modulated arc therapy (VMAT) treatment to multiple brain metastatic patients is an efficient stereotactic radiosurgery (SRS) option. However, the current clinical practice of single-isocenter SRS does not account for patient setup uncertainty, which degrades treatment delivery accuracy. This study quantifies the loss of target coverage and potential collateral dose to normal tissue due to clinically observable isocenter misalignment. Methods and materials Nine patients with 61 total tumors (2-16 tumors/patient) who underwent Gamma Knife® SRS were replanned in Eclipse™ using 10 megavoltages (MV) flattening-filter-free (FFF) bream (2400 MU/min), using a single-isocenter VMAT plan, similar to HyperArc™ VMAT plan. Isocenter was placed in the geometric center of the tumors. The prescription was 20 Gy to each tumor. Average gross tumor volume (GTV) and planning target volume (PTV) were 1.1 cc (0.02-11.5 cc) and 1.9 cc (0.11-18.8 cc), respectively, derived from MRI images. The average isocenter to tumor distance was 5.5 cm (1.6-10.1 cm). Six-degrees of freedom (6DoF) random and systematic residual set up errors within [±2 mm, ±2o] were generated using an in-house script in Eclipse based on our pre-treatment daily cone-beam CT imaging shifts and recomputed for the simulated VMAT plan. Relative loss of target coverage as a function of tumor size and distance to isocenter were evaluated as well as collateral dose to organs-at risk (OAR). Results The average beam-on time was less than six minutes. However, loss of target coverage for clinically observable setup errors were, on average, 7.9% (up to 73.1%) for the GTV (p < 0.001) and 21.5% for the PTV (up to 93.7%; p < 0.001). The correlation was found for both random and systematic residual setup errors with tumor sizes; there was a greater loss of target coverage for small tumors. Due to isocenter misalignment, OAR doses fluctuated and potentially receive higher doses than the original plan. Conclusion A single-isocenter VMAT SRS treatment (similar to HyperArc™ VMAT) to multiple brain metastases was fast with < 6 min of beam-on time. However, due to small residual set up errors, single-isocenter VMAT, in its current use, is not an accurate SRS treatment modality for multiple brain metastases. Loss of target coverage was statistically significant, especially for smaller lesions, and may not be clinically acceptable if left uncorrected. Further investigation of correction strategies is underway.

Novel Treatment For Non-Small Cell Lung Cancer With Brain Metastases

Brain metastases is common in patients with non-small cell lung cancer (NSCLC) and it is associated with poorer prognosis. Several options to control the secondary brain tumors in the context include chemotherapy, whole-brain radiation, stereotactic surgery, surgery. However, chemotherapy is ineffective to those patients because of poor penetration through the blood-brain barrier. Whole-brain radiation therapy used to be a standard option for brain metastases. However, it potentially damages normal brain tissues and causes neurocognitive decline. Stereotactic radiotherapy has been considered in cases of three or fewer lesions, and the lesions less than 3 cm. In selective cases, surgical removal of brain metastases can be done. These local therapies were accompanied by systemic treatment due to spreading of the cancer. Recently, molecular targeted therapy has opened up a new era in cancer treatment, especially NSCLC with brain metastases. In this review, we discuss brain metastases occurring in NSCLC patients with driver gene mutations with some briefly demonstrated cases.

Impact of Tyrosine Kinase Inhibitors (TKIs) Combined With Radiation Therapy for the Management of Brain Metastases From Renal Cell Carcinoma

Background: Targeted therapy has transformed the outcome for patients with metastatic renal cell carcinoma. Their efficacy and safety have also been demonstrated in brain metastatic RCC. Preclinical evidence suggests synergism of radiation and tyrosine kinase inhibitors. Consequently, several studies have compared their efficacy in the treatment of RCC brain metastases to the era of brain management with surgery/radiation only.

Objectives: We seek to systematically review and meta-analyze the results of those studies that involved comparative intervention groups of brain management; TKIs, and never used TKIs.

Methods and Materials: Online databases (PubMed, EMBASE, Cochrane library, and ClinicalTrials.gov) were searched for comparative studies. Overall survival as the primary outcome of interest, and local brain control, distant control, and adverse events as secondary outcomes of interest were recorded for meta-analysis. Hazard ratios were pooled together using Review Manager 5.3. Fixed effects or random effects model were adopted according to the level of heterogeneity. Subgroup analysis included studies that involved SRS as the local treatment of management.

Results: Overall 7 studies (n = 897) were included for meta-analysis. TKI use was associated with better survival (HR 0.60 [0.52, 0.69], p < 0.00001) and local brain control (HR 0.34 [0.11, 0.98], p = 0.05). SRS subgroup also revealed significantly better survival (HR 0.61 [0.44, 0.83], p = 0.002) and local brain control (HR 0.19 [0.08, 0.45], p = 0.0002). Distant brain control (HR 0.95 [0.67, 1.35], p = 0.79) and brain progression free survival were unaffected (HR 0.94 [0.56, 1.56], p = 0.80). Only one study (n = 376) reported significantly greater 12-months cumulative incidence of radiation necrosis with TKI use within 30 days of SRS (10.9 vs. 6.4%, p = 0.04).

Conclusions: TKIs use in combination with SRS is safe and effective for treating RCC brain metastases. Larger randomized controlled trials are warranted to validate the results.

Can stress promote the pathophysiology of brain metastases? A critical review of biobehavioral mechanisms

Chronic stress can promote tumor growth and progression through immunosuppressive effects and bi-directional interactions between tumor cells and their microenvironment. β-Adrenergic receptor signaling plays a critical role in mediating stress-related effects on tumor progression. Stress-related mechanisms that modulate the dissemination of tumor cells to the brain have received scant attention. Brain metastases are highly resistant to chemotherapy and contribute considerably to morbidity and mortality in various cancers, occurring in up to 20% of patients in some cancer types. Understanding the mechanisms promoting brain metastasis could help to identify interventions that improve disease outcomes. In this review, we discuss biobehavioral, sympathetic, neuroendocrine, and immunological mechanisms by which chronic stress can impact tumor progression and metastatic dissemination to the brain. The critical role of the inflammatory tumor microenvironment in tumor progression and metastatic dissemination to the brain, and its association with stress pathways are delineated. We also discuss translational implications for biobehavioral and pharmacological interventions.

SNORA71B promotes breast cancer cells across blood-brain barrier by inducing epithelial-mesenchymal transition

Background

Brain metastasis (BM) is a dreadful complication that significantly impacts the quality of life in breast cancer patients. A key process during brain metastasis is the migration of cancer cells across blood–brain barrier (BBB). However, the role of snoRNAs regulating BBB in BM is still unknown.

Methods

Here SNORic and GEO databases were used to identify differentially expressed snoRNAs between brain metastatic and non-metastatic breast cancer (BC) tissues. The effects of SNORA71B on the capacities of proliferation, migration, invasion, epithelial-mesenchymal transition (EMT), and BBB invasion of BC cells were evaluated by CCK8, transwell, western blot, and BBB model, respectively.

Results

SNORA71B was highly expressed in high BM BC tissues and cells compared to low BM BC controls. Survival analysis revealed high expression of SNORA71B was significantly associated with poor PPS and OS in breast cancer patients. ROC curve showed that SNORA71B might act as biomarker for breast cancer. Moreover, SNORA71B significantly promoted proliferation, migration, and invasion of BC cells with different BM abilities. Importantly, SNORA71B promoted the EMT process of low BM BC cells. SNORA71B knockdown inhibited the high BM BC cells across BBB, while EMT activator dramatically abrogated this inhibited effect.

Conclusions

In conclusion, SNORA71B promotes BC cells across the BBB partly via inducing EMT.

Tyrosine Kinase Inhibitors Could Be Effective Against Non-small Cell Lung Cancer Brain Metastases Harboring Uncommon EGFR Mutations

Background: The significance of uncommon epidermal growth factor receptor (EGFR) mutations in patients with non-small cell lung cancer (NSCLC) and brain metastasis (BM) remains unclear. Cerebrospinal fluid (CSF) liquid biopsy is a novel tool for assessing EGFR mutations in BM. This study aimed to evaluate the EGFR mutations in patients with NSCLC and newly diagnosed BM and to examine the effect of EGFR tyrosine kinase inhibitors (TKI) on BM harboring CSF-tested uncommon EGFR mutations.

Methods: This was a prospective study of 21 patients with NSCLC and BM diagnosed between 04/2018 and 01/2019. CSF was obtained to detect the BM EGFR mutations by next-generation sequencing. BM characteristics at magnetic resonance imaging (MRI) and EGFR-TKI response were examined.

Results: Of 21 patients with NSCLC, 10 (47.6%) had leptomeningeal metastasis (LM), while 11 (52.4%) had brain parenchymal metastasis (BPM); 13 (61.9%) had confirmed EGFR mutation-positive primary tumors. The uncommon mutation rate in CSF ctDNA was 33.3% (7/21). Among those with EGFR mutation-positive primary tumors, the rate of uncommon EGFR mutations in CSF was 53.8% (7/13). Uncommon EGFR mutations were more common in patients with LM than in patients with PBM (6/11, 54.5% vs. 1/10, 10%), and included G719A, L861Q, L703P, and G575R. TKI was effective for four patients with BMs harboring uncommon EGFR mutations.

Conclusion: In patients with NSCLC and LM, the rate of uncommon EGFR mutation was high. The BMs with uncommon EGFR mutations seem to respond to EGFR-TKI treatment. CSF liquid biopsy could reveal the EGFR genetic profile of the BM and help guide treatment using small-molecule TKI.

Antibodies for the Treatment of Brain Metastases, a Dream or a Reality?

The incidence of brain metastases (BM) in cancer patients is increasing. After diagnosis, overall survival (OS) is poor, elicited by the lack of an effective treatment. Monoclonal antibody (mAb)-based therapy has achieved remarkable success in treating both hematologic and non-central-nervous system (CNS) tumors due to their inherent targeting specificity. However, the use of mAbs in the treatment of CNS tumors is restricted by the blood-brain barrier (BBB) that hinders the delivery of either small-molecules drugs (sMDs) or therapeutic proteins (TPs). To overcome this limitation, active research is focused on the development of strategies to deliver TPs and increase their concentration in the brain. Yet, their molecular weight and hydrophilic nature turn this task into a challenge. The use of BBB peptide shuttles is an elegant strategy. They explore either receptor-mediated transcytosis (RMT) or adsorptive-mediated transcytosis (AMT) to cross the BBB. The latter is preferable since it avoids enzymatic degradation, receptor saturation, and competition with natural receptor substrates, which reduces adverse events. Therefore, the combination of mAbs properties (e.g., selectivity and long half-life) with BBB peptide shuttles (e.g., BBB translocation and delivery into the brain) turns the therapeutic conjugate in a valid approach to safely overcome the BBB and efficiently eliminate metastatic brain cells.

Extracranial systemic antitumor response through the abscopal effect induced by brain radiation in a patient with metastatic melanoma

The abscopal effect is a term that has been used to describe the phenomenon in which localized radiation therapy treatment of a tumor lesion triggers a spontaneous regression of metastatic lesion(s) at a non-irradiated distant site(s). Radiation therapy induced abscopal effects are believed to be mediated by activation and stimulation of the immune system. However, due to the brain's distinctive immune microenvironment, extracranial abscopal responses following cranial radiation therapy have rarely been reported. In this report, we describe the case of 42-year-old female patient with metastatic melanoma who experienced an abscopal response following her cranial radiation therapy for her brain metastasis. The patient initially presented with a stage III melanoma of the right upper skin of her back. Approximately 5 years after her diagnosis, the patient developed a large metastatic lesion in her upper right pectoral region of her chest wall and axilla. Since the patient's tumor was positive for BRAF and MEK, targeted therapy with dabrafenib and trametinib was initiated. However, the patient experienced central nervous system (CNS) symptoms such as headache and disequilibrium and developed brain metastases prior to the start of targeted therapy. The patient received radiation therapy to a dose of 30 Gy delivered in 15 fractions to her brain lesions while the patient was on dabrafenib and trametinib therapy. The patient's CNS metastases improved significantly within weeks of her therapy. The patient's non-irradiated large extracranial chest mass and axilla mass also shrank substantially demonstrating the abscopal effect during her CNS radiation therapy. Following radiation therapy of her residual chest lesions, the patient was disease free clinically and her CNS lesions had regressed. However, when the radiation therapy ended and the patient continued her targeted therapy alone, recurrence outside of her previously treated fields was noted. The disease recurrence could be due to the possibility of developing BRAF resistance clones to the BRAF targeted therapy. The patient died eventually due to wide spread systemic disease recurrence despite targeted therapy.

Targeting the PI3K/Akt/mTOR pathway with the pan-Akt inhibitor GDC-0068 in PIK3CA-mutant breast cancer brain metastases

BACKGROUND

Activating mutations in the pathway of phosphatidylinositol-3 kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) occur in 43-70% of breast cancer brain metastasis patients. To date, the treatment of these patients presents an ongoing challenge, mainly because of the lack of targeted agents that are able to sufficiently penetrate the blood-brain barrier. GDC-0068 is a pan-Akt inhibitor that has shown to be effective in various preclinical tumor models as well as in clinical trials. The purpose of this study was to analyze the efficacy of GDC-0068 in a breast cancer brain metastases model.

METHODS

In in vitro studies, antitumor activity of GDC-0068 was assessed in breast cancer cells of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA)-mutant and PIK3CA-wildtype breast cancer cell lines using cell viability and apoptosis assays, cell cycle analysis, and western blots. In vivo, the efficacy of GDC-0068 was analyzed in a PIK3CA-mutant breast cancer brain metastasis orthotopic xenograft mouse model and evaluated by repeated bioluminescent imaging and immunohistochemistry.

RESULTS

GDC-0068 decreased cell viability, induced apoptosis, and inhibited phosphorylation of proline rich Akt substrate 40 kDa and p70 S6 kinase in a dose-dependent manner in PIK3CA-mutant breast cancer brain metastatic cell lines compared with PIK3CA-wildtype cell lines. In vivo, treatment with GDC-0068 notably inhibited the growth of PIK3CA-mutant tumors and resulted in a significant survival benefit compared with sham, whereas no effect was detected in a PIK3CA-wildtype model.

CONCLUSIONS

This study suggests that the Akt inhibitor GDC-0068 may be an encouraging targeted treatment strategy for breast cancer brain metastasis patients with activating mutations in the PI3K pathway. These data provide a rationale to further evaluate the efficacy of GDC-0068 in patients with brain metastases.

Systemic high-dose intravenous methotrexate in patients with central nervous system metastatic breast cancer

Background

Infusion of high-dose intravenous methotrexate (MTX) has been demonstrating to penetrate the blood-brain barrier. The aim of this present study was to assess the efficacy and safety of high dose MTX in patients with central nervous system (CNS) metastases of breast cancer.

Methods

Twenty-two patients with CNS metastases treated by MTX (3 g/m2) between April 2004 and October 2009 were enrolled. Clinical response rate, time to progression (TTP), overall survival (OS), and safety were assessed.

Results

In terms of brain metastases, 2 patients (9%) achieved a partial response, 10 patients (45%) had disease stabilization, and 10 patients (45%) had disease progression. In others metastatic sites, 7 patients (39%) achieved a disease stabilization, and 11 patients (61%) had disease progression. TTP and OS were 2.1 (95%CI 1.4–2.9) and 6.3 (95%CI 1.8–10) months, respectively.

Conclusion

High-dose MTX demonstrated a moderate activity at 3 g/m². Nonetheless, the favorable toxicity profile should suggest the possibility to increase the dosage and further study are planned.

Predictive value of a nomogram for melanomas with brain metastases at initial diagnosis

BACKGROUND

Estimation of incidence and prognosis of melanomas with brain metastases (MBM) at initial diagnosis based on a large cohort is lacking in current research. This study aims to construct an effective prognostic nomogram for newly diagnosed MBM.

MATERIALS AND METHODS

Patients diagnosed with melanomas from Surveillance, Epidemiology, and End Results program between 2010 and 2014 were enrolled in our study. Risk factors predicting brain metastases (BM) were identified using logistic regression analysis. Cox regression analysis was performed to identify prognostic factors of overall survival (OS). Nomogram for estimating 6-, 9-, and 12-month OS was established based on Cox regression analysis. The discriminative ability and calibration of the nomogram were tested using C statistics, calibration plots, and Kaplan-Meier curves.

RESULTS

Sixty-two thousand three hundred and sixty-nine melanoma patients were enrolled, including 928 with BM. Sex, marital status, insurance status, subsite, surgery of primary sites, radiation, chemotherapy, bone metastases, liver metastases, and lung metastases were associated with MBM at initial diagnosis. On multivariable Cox regression, the following eight variables were incorporated in the prediction of OS: age, unmarried status, absence of surgery to primary sites or unknown, absence of radiation or unknown, absence of chemotherapy or unknown, with bone metastases, with liver metastases, and with lung metastases. The nomogram showed good predictive ability as indicated by discriminative ability and calibration, with the C statistics of 0.716 (95% CI, 0.695-0.737).

CONCLUSIONS

The incidence and prognosis of MBM patients were well estimated in this study based on a large cohort. The nomogram performed well and could be a useful tool to predict prognosis.

Superior Prognostic Value of Cumulative Intracranial Tumor Volume Relative to Largest Intracranial Tumor Volume for Stereotactic Radiosurgery-Treated Brain Metastasis Patients

BACKGROUND

Two intracranial tumor volume variables have been shown to prognosticate survival of stereotactic-radiosurgery-treated brain metastasis patients: the largest intracranial tumor volume (LITV) and the cumulative intracranial tumor volume (CITV).

OBJECTIVE

To determine whether the prognostic value of the Scored Index for Radiosurgery (SIR) model can be improved by replacing one of its components-LITV-with CITV.

METHODS

We compared LITV and CITV in terms of their survival prognostication using a series of multivariable models that included known components of the SIR: age, Karnofsky Performance Score, status of extracranial disease, and the number of brain metastases. Models were compared using established statistical measures, including the net reclassification improvement (NRI > 0) and integrated discrimination improvement (IDI). The analysis was performed in 2 independent cohorts, each consisting of ∼3000 patients.

RESULTS

In both cohorts, CITV was shown to be independently predictive of patient survival. Replacement of LITV with CITV in the SIR model improved the model's ability to predict 1-yr survival. In the first cohort, the CITV model showed an NRI > 0 improvement of 0.2574 (95% confidence interval [CI] 0.1890-0.3257) and IDI of 0.0088 (95% CI 0.0057-0.0119) relative to the LITV model. In the second cohort, the CITV model showed a NRI > 0 of 0.2604 (95% CI 0.1796-0.3411) and IDI of 0.0051 (95% CI 0.0029-0.0073) relative to the LITV model.

CONCLUSION

After accounting for covariates within the SIR model, CITV offers superior prognostic value relative to LITV for stereotactic radiosurgery-treated brain metastasis patients.