Treatment of brain metastasis from lung cancer

A systematic review of brain metastases from lung cancer using magnetic resonance neuroimaging: Clinical and technical aspects

INTRODUCTION

Brain metastases (BMs) are common in lung cancer (LC) and are associated with poor prognosis. Magnetic resonance imaging (MRI) plays a vital role in the detection, diagnosis and management of BMs. This review summarises recent advances in MRI techniques for BMs from LC.

METHODS

This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive literature search was conducted in three electronic databases: PubMed, Scopus and the Web of Science. The search was limited to studies published between January 2000 and March 2023. The quality of the included studies was evaluated using appropriate tools for different study designs. A narrative synthesis was carried out to describe the key findings of the included studies.

RESULTS

Sixty-five studies were included. Standard MRI sequences such as T1-weighted (T1w), T2-weighted (T2w) and fluid-attenuated inversion recovery (FLAIR) were commonly used. Advanced techniques included perfusion-weighted imaging (PWI), diffusion-weighted imaging (DWI) and radiomics analysis. DWI and PWI parameters could distinguish tumour recurrence from radiation necrosis. Radiomics models predicted genetic mutations and the risk of BMs. Diagnostic accuracy was improved with deep learning (DL) approaches. Prognostic factors such as performance status and concurrent chemotherapy impacted survival.

CONCLUSION

Advanced MRI techniques and specialised MRI methods have emerging roles in managing BMs from LC. PWI and DWI improve diagnostic accuracy in treated BMs. Radiomics and DL facilitate personalised prognosis and treatment. Magnetic resonance imaging plays a key role in the continuum of care for BMs of patients with LC, from screening to treatment monitoring.

Brain diffusion MRI biomarkers after oncology treatments

In addition to providing a measurement of the tumor's size and dimensions, magnetic resonance imaging (MRI) provides excellent noninvasive radiographic detection of tumor location. The MRI technique is an important modality that has been shown to be useful in the prognosis, diagnosis, treatment planning, and evaluation of response and recurrence in solid cancers. Diffusion-weighted imaging (DWI) is an imaging technique that quantifies water mobility. This imaging approach is good for identifying sub-voxel microstructure of tissues, correlates with tumor cellularity, and has been proven to be valuable in the early assessment of cytotoxic treatment for a variety of malignancies. Diffusion tensor imaging (DTI) is an MRI method that assesses the preferred amount of water transport inside tissues. This enables precise measurements of water diffusion, which changes according to the direction of white matter fibers, their density, and myelination. This measurement corresponds to some related variables: fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD), and others. DTI biomarkers can detect subtle changes in white matter microstructure and integrity following radiation therapy (RT) or chemoradiotherapy, which may have implications for cognitive function and quality of life. In our study, these indices were evaluated after brain chemoradiotherapy.

Can we predict overall survival using machine learning algorithms at 3-months for brain metastases from non-small cell lung cancer after gamma knife radiosurgery?

Gamma knife radiosurgery (GRKS) is widely used for patients with brain metastases; however, predictions of overall survival (OS) within 3-months post-GKRS remain imprecise. Specifically, more than 10% of non-small cell lung cancer (NSCLC) patients died within 8 weeks of post-GKRS, indicating potential overtreatment. This study aims to predict OS within 3-months post-GKRS using machine learning algorithms, and to identify prognostic features in NSCLC patients. We selected 120 NSCLC patients who underwent GKRS at Chungbuk National University Hospital. They were randomly assigned to training group (n = 80) and testing group (n = 40) with 14 features considered. We used 3 machine learning (ML) algorithms (Decision tree, Random forest, and Boosted tree classifier) to predict OS within 3-months for NSCLC patients. And we extracted important features and permutation features. Data validation was verified by physician and medical physicist. The accuracy of the ML algorithms for predicting OS within 3-months was 77.5% for the decision tree, 72.5% for the random forest, and 70% for the boosted tree classifier. The important features commonly showed age, receiving chemotherapy, and pretreatment each algorithm. Additionally, the permutation features commonly showed tumor volume (>10 cc) and age as critical factors each algorithm. The decision tree algorithm exhibited the highest accuracy. Analysis of the decision tree visualized data revealed that patients aged (>71 years) with tumor volume (>10 cc) were increased risk of mortality within 3-months. The findings suggest that ML algorithms can effectively predict OS within 3-months and identify crucial features in NSCLC patients. For NSCLC patients with poor prognoses, old age, and large tumor volumes, GKRS may not be a desirable treatment.

Economic burden in patients with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC), with or without brain metastases, receiving first-line ALK inhibitors

INTRODUCTION

This observational study describes the real-world economic burden in patients with anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer (NSCLC) receiving a first-line ALK inhibitor, and the economic impact of brain metastases (BM).

METHODS

Administrative claims data (Truven Health MarketScan® Commercial Claims and Encounters database and Medicare Supplemental and Coordination of Benefits database; January 1, 2015-March 31, 2020) for adult patients with ALK+ NSCLC who received a first-line ALK inhibitor were retrospectively reviewed. Healthcare costs and resource utilization were calculated on a per-patient-per-month (PPPM) basis and stratified by the presence or absence of BM prior to first-line ALK inhibitor. Factors associated with costs were identified.

RESULTS

A total of 496 patients were eligible for analysis. Mean PPPM total healthcare costs were $21,961 for all patients receiving up to 1 year of a first-line ALK inhibitor. Patients were significantly more likely to have higher mean PPPM total costs if they had BM prior to first-line ALK inhibitor (vs. no BM; odds ratio: 1.11; 95% confidence interval: 1.02, 1.21; p = 0.013). Mean PPPM days of hospital stay (p = 0.0056), and inpatient hospital visits (p = 0.0030) were significantly higher for patients with BM compared to no BM. The main cost drivers for non-inpatient procedures for all patients were medications, radiation therapy, and other diagnostic procedures.

CONCLUSIONS

The economic burden in patients with ALK+ NSCLC receiving a first-line ALK inhibitor was high. Patients with ALK+ NSCLC and BM had higher healthcare costs and resource utilization than patients without BM.

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

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

A study of the prognosis of patients with limited-stage small cell lung cancer who did or did not receive prophylactic cranial irradiation after effective chemoradiotherapy

Objective

To investigate the prognosis of patients with LS-SCLC who responded to chest chemoradiotherapy but did not receive PCI.

Methods

A retrospective analysis was conducted on LS-SCLC patients who had achieved complete remission (CR) or partial remission (PR) after definitive chemoradiotherapy but did not receive PCI. The survival rates were calculated using Kaplan-Meier method. The prognosis was analyzed using Cox proportional hazard regression model. The main endpoint was OS.

Results

Of the 500 patients with LS-SCLC admitted between June 2002 and January 2018, 327 achieved CR or PR after definitive chest chemoradiotherapy, 103 did not receive PCI, and 63 of them developed brain metastases (BM). The 1-year and 3-year OS rates in PCI group were 87.5% and 42.3% respectively, versus 70.4% and 20.9% for non-PCI group(P=0.002). The median survival time after BM was 8.7 months (range: 0.3-48.7), and 3-year OS rate was 15.0%, the median survival time of patients without BM was 20.1 months (range: 2.9-79.4), and 3-year OS was 33.4% (P=0.014). Patients with BM were subsequently treated with palliative therapy. Multivariate analysis showed that compared with no treatment, brain radiotherapy alone (HR: 0.131, 95%CI: 0.035-0.491, P=0.003) and radiotherapy combined with chemotherapy (HR: 0.039, 95%CI: 0.008-0.194, P<0.001) significantly reduced the risk of death. Multiple BM (HR: 2.391, 95%CI: 1.082-5.285, P=0.031) was an independent adverse prognostic factor for OS.

Conclusion

LS-SCLC patients who achieved good response after chest chemoradiotherapy without receiving PCI were prone to develop BM and have a poor prognosis. Multiple BM was an independent adverse prognostic factor. PCI remains the standard of care for LS-SCLC patients.

A study of non small cell lung cancer (NSCLC) patients with brain metastasis: A single centre experience

BACKGROUND

Lung cancer is the leading cause of cancer death with the majority of cases being non-small cell lung cancer (NSCLC) [1]. A common complication of NSCLC is brain metastasis (BM) [2, 3], where the prognosis remains poor despite new treatments. Real world data complements data gained from clinical trials, providing information on patients excluded from prospective research [4]. However, information from patient notes may prove incomplete and difficult to extract. We developed an algorithm to identify patients in our clinical database with brain metastasis from the electronic health record (EHR).

METHODS

We retrospectively extracted data from the EHR of patients managed at a large teaching hospital between 2007 and 2018. Using the ICD-10 code C34, for lung cancer, our algorithm used phrases associated with BMs to search the unstructured text of radiology reports. Summary statistics and univariant analysis was performed for overall survival.

RESULTS

818 patients were identified as potentially having BM and 453 patients were confirmed on clinical review of their records. The median age of patients was 69 years, 50% were female and 66% had a performance status of >2. 12.2% had an identifiable mutation and 11.5% were identified as PD-L1 positive. In the first line setting, 65% of patients received symptomatic treatment, 23% received systemic anticancer therapy (SACT), 6.1% surgery and 10% radiotherapy, of which 6.5% had external beam and 3.5% stereotactic radiosurgery. Regarding those treated with SACT, 35% had an intracranial response to treatment (3% had complete response, 32% had a partial response). Median survival was 2 months (1.9 - 2.4 months 95% CI).

CONCLUSION

The real-world prognosis for NSCLC patients with BMs is poor. By using an algorithm, we have reported outcomes on a comprehensive cohort of patients which helps identify those for whom an active treatment approach is appropriate.

Brain metastases from small cell lung cancer and non-small cell lung cancer: comparison of spatial distribution and identification of metastatic risk regions

PURPOSE

This study aims to investigate the spatial distribution difference of brain metastases (BM) between small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC) and to identify the metastatic risk in brain regions.

METHODS

T1-enhanced MR images of 2997 BM from 728 eligible patients with SCLC and NSCLC were retrospectively reviewed by three independent medical institutions in China. All images were spatially normalised according to the Montreal Neurological Institute space, following BM delineation confirmed by three senior radiologists. The brain regions in the normalised images were identified based on the merged Anatomical Automatic Labeling atlas, and all BM locations were mapped onto these brain regions. Two-tailed proportional hypothesis testing was used to compare the BM observed rate with the expected rate based on the region's volume, and metastatic risk regions were finally identified.

RESULTS

In SCLC and NSCLC, BM was mainly present in the deep white matter (22.51% and 17.96%, respectively), cerebellar hemisphere (9.84% and 7.46%, respectively) and middle frontal gyrus (6.72% and 7.97%, respectively). The cerebellar hemisphere was a high-risk brain region in the SCLC. The precentral gyrus, middle frontal gyrus, paracentral lobule and cerebellar hemisphere were high-risk BM in the NSCLC. The inferior frontal gyrus and the temporal pole were a low-risk brain region in the SCLC and NSCLC, respectively.

CONCLUSION

The spatial BM distribution between SCLC and NSCLC is similar. Several critical brain regions had relatively low BM frequency in both SCLC and NSCLC, where a low-dose radiation distribution can be delivered due to adequate preoperative evaluations.

Principles of Lung Cancer Metastasis to Brain

Lung cancer is a disease associated with significant morbidity and mortality on a global setting. This form of cancer commonly gives raise to metastatic lesions the brain, which can further worsen outcomes. In this focused review, we discuss an overview of lung cancers that metastasize to the brain: known risk factors; means of detection and diagnosis; and options for treatment including a comparison between surgical resection, stereotactic radiosurgery, and whole-brain radiation therapy. These interventions are still being assessed by clinical trials and continue to be modified through evidence-based practice.

Predicting EGFR mutation status by a deep learning approach in patients with non-small cell lung cancer brain metastases

PURPOSE

Non-small cell lung cancer (NSCLC) tends to metastasize to the brain. Between 10 and 60% of NSCLCs harbor an activating mutation in the epidermal growth-factor receptor (EGFR), which may be targeted with selective EGFR inhibitors. However, due to a high discordance rate between the molecular profile of the primary tumor and the brain metastases (BMs), identifying an individual patient's EGFR status of the BMs necessitates tissue diagnosis via an invasive surgical procedure. We employed a deep learning (DL) method with the aim of noninvasive detection of the EGFR mutation status in NSCLC BM.

METHODS

We retrospectively collected clinical, radiological, and pathological-molecular data of all the NSCLC patients who had been diagnosed with BMs and underwent resection of their BM during 2009-2019. The study population was then divided into two groups based upon EGFR mutational status. We further employed a DL technique to classify the two groups according to their preoperative magnetic resonance imaging features. Augmentation techniques, transfer learning approach, and post-processing of the predicted results were applied to overcome the relatively small cohort. Finally, we established the accuracy of our model in predicting EGFR mutation status of BM of NSCLC.

RESULTS

Fifty-nine patients were included in the study, 16 patients harbored EGFR mutations. Our model predicted mutational status with mean accuracy of 89.8%, sensitivity of 68.7%, specificity of 97.7%, and a receiver operating characteristic curve value of 0.91 across the 5 validation datasets.

CONCLUSION

DL-based noninvasive molecular characterization is feasible, has high accuracy and should be further validated in large prospective cohorts.

Osimertinib in EGFR-Mutated Lung Cancer: A Review of the Existing and Emerging Clinical Data

The use of epidermal growth factor receptor (EGFR) inhibitors such as osimertinib has improved outcomes and quality of life for patients with EGFR-mutated non-small cell lung cancer (NSCLC). Osimertinib has become the preferred EGFR tyrosine kinase inhibitor (TKIs) for patients with these mutations after demonstrating superior efficacy compared to first generation EGFR TKIs, such as erlotinib and gefitinib. More recently osimertinib has also shown to be beneficial in patients with resectable NSCLC harboring EGFR mutations irrespective of whether they received adjuvant chemotherapy or not. The drug is now FDA approved in this setting. With osimertinib being used more commonly in earlier stage and front-line settings, we are more likely to see patients who develop resistance to this drug. The aim of this review is to provide a comprehensive review of the data with osimertinib in EGFR mutation positive NSCLC, potential resistance mechanisms and an overview of key ongoing clinical trials.

TRIM28 Selective Nanobody Reduces Glioblastoma Stem Cell Invasion

Glioblastoma (GB), is the most common and aggressive malignant primary brain tumour in adults. Intra- and inter-tumour heterogeneity, infiltrative GB cell invasion and presence of therapy-resistant GB stem cells (GSCs) represent major obstacles to favourable prognosis and poor therapy response. Identifying the biomarkers of the most aggressive tumour cells and their more efficient targeting strategies are; therefore, crucial. Recently, transcription factor TRIM28 has been identified as a GB biomarker and, in this study, we have shown high expression of TRIM28 in GB and in low grade gliomas as well as higher expression in GSCs vs. differentiated GB cells, although in both cases not significant. We demonstrated significant in vitro inhibition of GB cells and GSCs invasiveness and spread in zebrafish brains in vivo by anti-TRIM28 selective nanobody NB237. TRIM28 was also enriched in GB (tumour) core and associated with the expression of stem cell genes, but was not prognostic for overall survival. However, based on the above results, we conclude that TRIM28 nanobody NB237 offers a new opportunity as a GB therapeutic tool.

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.

Differentiating Small-Cell Lung Cancer From Non-Small-Cell Lung Cancer Brain Metastases Based on MRI Using Efficientnet and Transfer Learning Approach

Differentiation between small-cell lung cancer (SCLC) from non-small-cell lung cancer (NSCLC) brain metastases is crucial due to the different clinical behaviors of the two tumor types. We propose the use of a deep learning and transfer learning approach based on conventional magnetic resonance imaging (MRI) for non-invasive classification of SCLC vs. NSCLC brain metastases. Sixty-nine patients with brain metastasis of lung cancer origin were included. Of them, 44 patients had NSCLC and 25 patients had SCLC. Classification was performed with EfficientNet architecture on crop images of lesion areas and based on post-contrast T1-weighted, T2-weighted and FLAIR imaging input data. Evaluation of the model was carried out in a 5-fold cross-validation manner, and based on accuracy, precision, recall, F1 score and area under the receiver operating characteristic curve. The best classification results were obtained with multiparametric MRI input data (T1WI+c+FLAIR+T2WI), with a mean overall accuracy of 0.90 ± 0.04, and F1 score of 0.92 ± 0.05 for NSCLC and 0.87 ± 0.08 for SCLC for the validation data and an accuracy of 0.87 ± 0.05, with an F1 score of 0.88 ± 0.05 for NSCLC and 0.85 ± 0.05 for SCLC for the test dataset. The proposed method provides an automatic noninvasive method for the classification of brain metastasis with high sensitivity and specificity for differentiation between NSCLC vs. SCLC brain metastases. It may be used as a diagnostic tool for improving decision-making in the treatment of patients with these metastases. Further studies on larger patient samples are required to validate the current results.

A Rare Case of Diffuse Subependymal Periventricular Metastases from Small Cell Lung Carcinoma

Small cell lung cancer, whose essence is neuroendocrine tumors, makes up proximately 14-20% of all lung cancer circumstances. Compared to non-small cell lung cancer, its clinical manifestation seems more positive and has a tendency to disseminate earlier in the process of its natural past. About 10% of patients present with brain metastases at the time of provisional diagnosis and sometimes all along the course of their disease, there will be 40-50% of developed brain metastases in addition. Although metastases in the brain parenchyma are often found in patients with advanced lung cancer, periventricular metastases are rare. We report one case of diffuse subependymal periventricular metastases from small cell carcinoma of the lung.

Clinical Perspectives in Brain Metastasis

Brain metastases (BMs) are responsible for decline in neurological function, reduction in overall quality of life, and mortality from recurrent or untreatable lesions. Advances in diagnostics and imaging have led to increased detection of central nervous system (CNS) metastases in patients with progressive cancers. Improved control of extracranial systemic disease, and the limited ability of current therapeutics to cross the blood-brain barrier (BBB) also contribute to the increase in incidence of brain metastases, as tumor cells seek refuge in the brain. Surgery, chemotherapy, and/or radiation (whole-brain radiation therapy and stereotactic radiation surgery [WBRT/SRS]) are a clinically established treatment paradigm for patients with brain metastases. With the advent of genetic and molecular characterization of tumors and their immune microenvironment, clinical trials seek to include targeted drugs into the therapeutic regimen for eligible patients. Several challenges, like treatment of multiple CNS lesions, superior uptake of chemotherapy into the brain, and trials with multidisciplinary approaches, are now being clinically addressed.

Drug resistance occurred in a newly characterized preclinical model of lung cancer brain metastasis

Background

Cancer metastasis and drug resistance have traditionally been studied separately, though these two lethal pathological phenomena almost always occur concurrently. Brain metastasis occurs in a large proportion of lung cancer patients (~ 30%). Once diagnosed, patients have a poor prognosis surviving typically less than 1 year due to lack of treatment efficacy.

Methods

Human metastatic lung cancer cells (PC-9-Br) were injected into the left cardiac ventricle of female athymic nude mice. Brain lesions were allowed to grow for 21 days, animals were then randomized into treatment groups and treated until presentation of neurological symptoms or when moribund. Prior to tissue collection mice were injected with Oregon Green and ¹⁴C-Aminoisobutyric acid followed by an indocyanine green vascular washout. Tracer accumulation was determined by quantitative fluorescent microscopy and quantitative autoradiography. Survival was tracked and tumor burden was monitored via bioluminescent imaging. Extent of mutation differences and acquired resistance was measured in-vitro through half-maximal inhibitory assays and qRT-PCR analysis.

Results

A PC-9 brain seeking line (PC-9-Br) was established. Mice inoculated with PC-9-Br resulted in a decreased survival time compared with mice inoculated with parental PC-9. Non-targeted chemotherapy with cisplatin and etoposide (51.5 days) significantly prolonged survival of PC-9-Br brain metastases in mice compared to vehicle control (42 days) or cisplatin and pemetrexed (45 days). Further in-vivo imaging showed greater tumor vasculature in mice treated with cisplatin and etoposide compared to non-tumor regions, which was not observed in mice treated with vehicle or cisplatin and pemetrexed. More importantly, PC-9-Br showed significant resistance to gefitinib by in-vitro MTT assays (IC50 > 2.5 μM at 48 h and 0.1 μM at 72 h) compared with parental PC-9 (IC50: 0.75 μM at 48 h and 0.027 μM at 72 h). Further studies on the molecular mechanisms of gefitinib resistance revealed that EGFR and phospho-EGFR were significantly decreased in PC-9-Br compared with PC-9. Expression of E-cadherin and vimentin did not show EMT in PC-9-Br compared with parental PC-9, and PC-9-Br had neither a T790M mutation nor amplifications of MET and HER2 compared with parental PC-9.

Conclusion

Our study demonstrated that brain metastases of lung cancer cells may independently prompt drug resistance without drug treatment.

Neurocognitive Decline Following Radiotherapy: Mechanisms and Therapeutic Implications

The brain undergoes ionizing radiation (IR) exposure in many clinical situations, particularly during radiotherapy for malignant brain tumors. Cranial radiation therapy is related with the hazard of long-term neurocognitive decline. The detrimental ionizing radiation effects on the brain closely correlate with age at treatment, and younger age associates with harsher deficiencies. Radiation has been shown to induce damage in several cell populations of the mouse brain. Indeed, brain exposure causes a dysfunction of the neurogenic niche due to alterations in the neuronal and supporting cell progenitor signaling environment, particularly in the hippocampus—a region of the brain critical to memory and cognition. Consequent deficiencies in rates of generation of new neurons, neural differentiation and apoptotic cell death, lead to neuronal deterioration and lasting repercussions on neurocognitive functions. Besides neural stem cells, mature neural cells and glial cells are recognized IR targets. We will review the current knowledge about radiation-induced damage in stem cells of the brain and discuss potential treatment interventions and therapy methods to prevent and mitigate radiation related cognitive decline.

Tumor Mutational Burden Is Site Specific in Non–Small-Cell Lung Cancer and Is Highest in Lung Adenocarcinoma Brain Metastases

PURPOSE

Tumor mutational burden (TMB) is a developing biomarker in non–small-cell lung cancer (NSCLC). Little is known regarding differences between TMB and sample location, histology, or other biomarkers.

METHODS

A total of 3,424 unmatched NSCLC samples, including 2,351 lung adenocarcinomas (LUADs) and 1,073 lung squamous cell carcinomas (LUSCs), underwent profiling, including next-generation sequencing of 592 cancer-related genes, programmed death ligand 1 immunohistochemistry, and TMB. The rate TMB of 10 mutations per megabase (Mb) or greater was compared between primary and metastatic LUAD and LUSC. Molecular alteration frequency was compared at a cutoff of 10 mutations/Mb.

RESULTS

LUAD metastases were more likely to have a TMB of 10 mutations/Mb or greater compared with primary LUADs (38% v 25%; P < .001), and this difference was most pronounced with brain metastases (61% v 35% for other metastases; P < .001). The median TMB for LUAD brain metastases was 13 mutations/Mb compared with six mutations/Mb for primary LUADs. Variability existed for other LUAD metastasis sites, with adrenal metastases most likely to meet the cutoff of 10 mutations/Mb (51%) and bone metastases least likely to meet the cutoff (19%). TMB was more commonly 10 mutations/Mb or greater for LUSC primary tumors than for LUAD primary tumors (35% v 25%, respectively; P < .001). LUSC metastases were more likely to have a TMB of 10 mutations/Mb or greater than LUSC primary tumors. Poorly differentiated disease was more likely have a TMB of 10 mutations/Mb or greater when stratified by histology and primary tumor or metastasis. Site-specific molecular differences existed at this TMB cutoff including programmed death ligand 1 positivity and STK11 and KRAS mutation rate.

CONCLUSION

TMB is a site-specific biomarker in NSCLC with important spatial and histologic differences. TMB is more frequently 10 mutations/Mb or greater in LUAD and LUSC metastases and highest in LUAD brain metastases. Along this TMB cutoff, clinically informative distinctions exist in other tumor profiling characteristics. Further investigation is needed to expand on these findings.

Acute intracranial hypertension management in metastatic brain tumor: A French national survey

BACKGROUND

Brain metastases occur in 15-30% of cancer patients and their frequency has increased over time. They can cause intracranial hypertension, even in the absence of hydrocephalus. Emergency surgical management of brain metastasis-related intracranial hypertension is not guided by specific recommendations.

OBJECTIVE

We aimed to make a French national survey of emergency management of intracranial hypertension without hydrocephalus in the context of cerebral metastasis.

METHODS

A national online survey of French neurosurgeons from 16 centers was conducted, consisting of three clinical files, with multiple-choice questions on diagnostic and therapeutic management in different emergency situations.

RESULTS

In young patients without any previously known primary cancer, acute intracranial hypertension due to a seemingly metastatic single brain tumor indicated emergency surgery for all those interviewed; 61% aimed at complete resection; brain MRI was mandatory for 74%. When a primary cancer was known, 74% of respondents were more likely to propose surgery if an oncologist confirmed the possibility of adjuvant treatment; 27% were more likely to operate on an emergency basis when resection was scheduled after multi-disciplinary discussion, prior to acute degradation.

CONCLUSION

Currently, there is no consensus on the emergency management of intracranial hypertension in metastatic brain tumor patients. In case of previously known primary cancer, a discussion with the oncology team seems necessary, even in emergency. Decision criteria emerge from our literature review, but require analysis in further studies.

Timing of adjuvant radiation therapy and survival outcomes after surgical resection of intracranial non-small cell lung cancer metastases

OBJECTIVE

To investigate if delay of adjuvant radiotherapy (ART) beyond 6 post-operative weeks affects survival outcomes in patients undergoing craniotomy or craniectomy for resection of non-small cell lung cancer (NSCLC) intracranial metastases.

PATIENTS AND METHODS

We performed a retrospective analysis of 28 patients undergoing resection of intracranial metastases and ART at our institution from 2001 to 2016. We assessed survival outcomes for patients who received delayed versus non-delayed ART, as well as associated risk factors.

RESULTS

Among 28 patients, 8 (29%) had delayed ART beyond 6 post-operative weeks. Fifteen received stereotactic radiotherapy (SRT), 8 (29%) received whole brain radiotherapy (WBRT), and 5 (18%) received combination WBRT + SRT. There were no significant differences in ART modality or dosing, age, sex, number of intracranial metastases, primary metastasis volume, rates of chemotherapy, extracranial metastases, or post-operative functional scores between groups. Expected post-operative survival was shorter with delayed ART (7 months versus 28 months, P = 0.01). The most common reason for delayed ART was complicated post-operative course (n = 3.38%). Significant risk factors for delayed ART included non-routine discharge (P = 0.01) and additional invasive procedures between surgery and ART start date (P = 0.02).

CONCLUSIONS

Our results suggest delayed ART in patients undergoing surgical resection of intracranial NSCLC metastases is associated with shorter overall survival. However, risk factors for delayed ART, including non-routine discharge and the need for additional invasive procedures, may have in themselves reflected poorer clinical courses that may have also contributed to the observed survival differences.

Multidisciplinary expert opinion on the treatment consensus for patients with EGFR mutated NSCLC with brain metastases

The presence of an epidermal growth factor receptor (EGFR) mutation is associated with higher incidence of brain metastases in patients with non-small cell lung cancer (NSCLC); however, patients with synchronous brain metastases at diagnosis have generally been excluded from clinical trials. As there is limited clinical evidence for managing this patient population, a multidisciplinary group of Spanish medical and radiation oncologists, and neuro-oncologist with expertise treating brain metastases in lung cancer patients met with the aim of reaching and developing an expert opinion consensus on the management of patients with EGFR mutated NSCLC with brain metastases. This consensus contains 26 recommendations and 20 conclusion statements across 21 questions in 7 areas, as well as a first-line treatment algorithm.

Concurrent versus sequential whole brain radiotherapy and TKI in EGFR-mutated NSCLC patients with brain metastasis: A single institution retrospective analysis

To examine the outcomes of concurrent versus sequential whole-brain radiotherapy (WBRT) and epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) in nonsmall cell lung cancer (NSCLC) patients with EGFR mutation.Retrospectively 105 patients with NSCLC, brain metastasis, and EGFR mutation (Affiliated Hospital of Guangdong Medical University, 01/2011 to 12/2014) were grouped as: EGFR-TKIs alone (n = 39, group A), EGFR-TKIs + concurrent radiotherapy (n = 34, group B), and radiotherapy followed by EGFR-TKIs (n = 32, group C).The intracranial objective response rates of groups A, B, and C were 66.7%, 85.3%, and 75%, respectively (P < .05). The median intracranial progression-free survival of groups A, B, and C were 6.8, 12.4, and 9.1 months, respectively (P < .05). The median extracranial progression-free survival of groups A, B, and C were 7.8, 9.4, and 8.3 months, respectively (P > .05).EGFR-TKIs and WBRT by simultaneous application improved the short- and long-term benefits to patients with NSCLC brain metastasis carrying EGFR mutation compared to concurrent application or EGFR-TKIs alone without additional adverse events.

Lung cancer-associated brain metastasis: Molecular mechanisms and therapeutic options

BACKGROUND

Lung cancer is the most common cause of cancer-related mortality in humans. There are several reasons for this high rate of mortality, including metastasis to several organs, especially the brain. In fact, lung cancer is responsible for approximately 50% of all brain metastases, which are very difficult to manage. Understanding the cellular and molecular mechanisms underlying lung cancer-associated brain metastasis brings up novel therapeutic promises with the hope to ameliorate the severity of the disease. Here, we provide an overview of the molecular mechanisms underlying the pathogenesis of lung cancer dissemination and metastasis to the brain, as well as promising horizons for impeding lung cancer brain metastasis, including the role of cancer stem cells, the blood-brain barrier, interactions of lung cancer cells with the brain microenvironment and lung cancer-driven systemic processes, as well as the role of growth factor/receptor tyrosine kinases, cell adhesion molecules and non-coding RNAs. In addition, we provide an overview of current and novel therapeutic approaches, including radiotherapy, surgery and stereotactic radiosurgery, chemotherapy, as also targeted cancer stem cell and epithelial-mesenchymal transition (EMT)-based therapies, micro-RNA-based therapies and other small molecule or antibody-based therapies. We will also discuss the daunting potential of some combined therapies.

CONCLUSIONS

The identification of molecular mechanisms underlying lung cancer metastasis has opened up new avenues towards their eradication and provides interesting opportunities for future research aimed at the development of novel targeted therapies.

Simultaneous Resection of Multiple Metastatic Brain Tumors with Multiple Keyhole Craniotomies

BACKGROUND

The proper management of symptomatic patients with 2 or more brain metastases is not entirely clear, and the surgical outcomes of these patients undergoing multiple simultaneous craniotomies have not been well described. In this article, we describe patient outcomes after simultaneously resecting metastatic lesions through multiple keyhole craniotomies.

METHODS

We conducted a retrospective review of data obtained for all patients undergoing resection of multiple brain metastases in one operation between 2014 and 2016. We describe a technique for resecting multiple metastatic lesions and share the patient outcomes of this operation.

RESULTS

Twenty patients with 46 tumor resections were included in the study. The primary site of metastases for the majority of patients was lung, followed by melanoma, renal, breast, colon, and testes. Nine of 20 (45%) patients had 2 preoperative intracranial lesions, and 11 (55%) had three or more. Karnofsky performance scales were calculated for 14 patients: postoperatively 10 of 14 (71%) scores improved, 2 of 14 (14%) worsened, and 2 of 14 (14%) remained unchanged. After surgery, 9 of 14 (64%) patients were weaned off steroids by 2-month follow-up. The overall median survival time from date of surgery was 10.8 months.

CONCLUSIONS

We present patient outcomes after simultaneously resecting metastatic brain tumors through multiple keyhole craniotomies in symptomatic patients. Our results suggest comparable outcomes and similar surgical risk compared with those undergoing resection of a single brain metastasis. Resection of multiple brain metastases may improve Karnofsky Performance Scale scores in the early postoperative period and allow patients to be weaned from steroids.

Erlotinib intercalating pemetrexed/cisplatin versus erlotinib alone in Chinese patients with brain metastases from lung adenocarcinoma: a prospective, non-randomised, concurrent controlled trial (NCT01578668)

Objective

Erlotinib has a synergistic effect with pemetrexed for treating non-squamous non-small-cell lung cancer. We investigated the efficacy and safety of erlotinib (E) in combination with pemetrexed/cisplatin (E-P) in Chinese patients with lung adenocarcinoma with brain metastases.

Design

Patients who were erlotinib-naïve or pemetrexed-naïve were assigned in parallel to receive either E or E-P. The primary endpoint was the intracranial overall response rate (ORRi).

Results

Sixty-nine patients with lung adenocarcinoma with brain metastases received E (n=35) or E-P (n=34) from January 2012 to November 2014. Demographics and patient characteristics were well balanced between the two groups, including epidermal growth factor receptor (EGFR) status, sex, age, smoking status, Eastern Cooperative Oncology Group (ECOG) performance status, brain metastases and number of prior treatments. ORRi in the E-P arm was superior to that in the E arm (79% vs 48%, p=0.008). Compared with E as the first-line treatment, E-P was associated with better intracranial progression-free survival (PFSi, median: 9 vs 2 months, p=0.027) and systemic PFS (median: 8 vs 2 months, p=0.006). The most frequent E-related adverse events were higher in the combination arm. No new safety signals were detected. The side effects were tolerable, and there were no drug-related deaths.

Conclusion

Our study suggests that the E-P combination may be effective in Chinese patients with lung adenocarcinoma with brain metastases, with improved PFS in treatment-naïve patients. Toxicities are tolerable, and there are more E-related side effects.

Brain metastasis in non-small cell lung cancer (NSCLC) patients with uncommon EGFR mutations: a report of seven cases and literature review

Brain metastasis (BM) arising from non-small cell lung cancer (NSCLC) with rare epidermal growth factor receptor (EGFR) mutations is quite rare. The prognosis and therapeutic effects of BM remain enigmatic. To the best of our knowledge, this is the first report to make a separate analysis of BM from NSCLC patients with original uncommon EGFR mutations. We retrospectively reviewed 7 cases of BM arising from 42 cases of uncommon EGFR mutated lung cancer in Tianjin Medical University Cancer Institute and Hospital. We also performed a literature review to assess therapeutic features and outcomes.

Mechanisms of radiotherapy-associated cognitive disability in patients with brain tumours

Standard treatment of primary and metastatic brain tumours includes high-dose megavoltage-range radiation to the cranial vault. About half of patients survive >6 months, and many attain long-term control or cure. However, 50-90% of survivors exhibit disabling cognitive dysfunction. The radiation-associated cognitive syndrome is poorly understood and has no effective prevention or long-term treatment. Attention has primarily focused on mechanisms of disability that appear at 6 months to 1 year after radiotherapy. However, recent studies show that CNS alterations and dysfunction develop much earlier following radiation exposure. This finding has prompted the hypothesis that subtle early forms of radiation-induced CNS damage could drive chronic pathophysiological processes that lead to permanent cognitive decline. This Review presents evidence of acute radiation-triggered CNS inflammation, injury to neuronal lineages, accessory cells and their progenitors, and loss of supporting structure integrity. Moreover, injury-related processes initiated soon after irradiation could synergistically alter the signalling microenvironment in progenitor cell niches in the brain and the hippocampus, which is a structure critical to memory and cognition. Progenitor cell niche degradation could cause progressive neuronal loss and cognitive disability. The concluding discussion addresses future directions and potential early treatments that might reverse degenerative processes before they can cause permanent cognitive disability.

Icotinib combined whole brain radiotherapy for patients with brain metastasis from lung adenocarcinoma harboring epidermal growth factor receptor mutation

BACKGROUND

The brain is a metastatic organ that is most prone to lung adenocarcinoma (LAC). However, the prognosis of patients with brain metastasis remains very poor. In this study, we evaluated the efficacy of icotinib plus whole brain radiation therapy (WBRT) for treating patients with brain metastasis from epidermal growth factor receptor (EGFR)-mutated LAC.

METHODS

All patients received standard WBRT administered to the whole brain in 30 Gy in 10 daily fractions. Each patient was also instructed to take 125 mg icotinib thrice per day beginning from the first day of the WBRT. After completing the WBRT, maintenance icotinib was administered until the disease progressed or intolerable adverse effects were observed. Cranial progression-free survival (CPFS) and overall survival (OS) times were the primary endpoints.

RESULTS

A total of 43 patients were enrolled in this study. Two patients (4.7%) presented a complete response (CR), whereas 20 patients (46.5%) presented a partial response (PR). The median CPFS and OS times were 11.0 and 15.0 months, respectively. The one-year CPFS rate was 40.0% for the patients harboring EGFR exon 19 deletion and 16.7% for the patients with EGFR exon 21 L858R (P=0.027).

CONCLUSIONS

The concurrent administration of icotinib and WBRT exhibited favorable effects on the patients with brain metastasis. EGFR exon 19 deletion was predictive of a long CPFS following icotinib plus WBRT.

Clinical Outcomes of Gamma Knife Radiosurgery for Metastatic Brain Tumors from Gynecologic Cancer : Prognostic Factors in Local Treatment Failure and Survival

Objective

Brain metastases in gynecologic cancer (ovarian, endometrial, and cervical cancer) patients are rare, and the efficacy of Gamma Knife Radiosurgery (GKRS) to treat these had not been evaluated. We assessed the efficacy of GKRS and prognostic factors for tumor control and survival in brain metastasis from gynecologic cancers.

Methods

This retrospective study was approved by the institutional review board. From May 1995 to October 2012, 26 women (mean age 51.3 years, range 27–70 years) with metastatic brain tumors from gynecologic cancer were treated with GKRS. We reviewed their outcomes, radiological responses, and clinical status.

Results

In total 24 patients (59 lesions) were available for follow-up imaging. The median follow-up time was 9 months. The mean treated tumor volume at the time of GKRS was 8185 mm³ (range 10–19500 mm³), and the median dose delivered to the tumor margin was 25 Gy (range, 10–30 Gy). A local tumor control rate was 89.8% (53 of 59 tumors). The median overall survival was 9.5 months after GKRS (range, 1–102 months). Age-associated multivariate analysis indicated that the Karnofsky performance status (KPS), the recursive partitioning analysis (RPA) classification, and the number of treated lesions were significant prognostic factors for overall survival (HR=0.162, p=0.008, HR=0.107, p=0.038, and HR=2.897, p=0.045, respectively).

Conclusion

GKRS is safe and effective for the management of brain metastasis from gynecologic cancers. The clinical status of the patient is important in determining the overall survival time.

Assessment of intracranial metastases from neuroendocrine tumors/carcinoma

BACKGROUND

The most common sites of origin for neuroendocrine carcinoma are gastrointestinal tract and its accessory glands, and lungs.

MATERIALS AND METHODS

One-hundred fifty cases diagnosed with metastatic brain lesions were retrieved from hospital records within 5 years. For these cases, the primary neoplasm, histopathological classification, metastasis, treatment, and fate all were studied.

RESULTS

Intracranial deposits were detected in 10%. The primary lesion was in the lungs in 87% of patients, and 1 patient in the breast and 1 in esophagus. Pathological classification of the primary lesion was Grade 2 (MIB-1: 3-20%) in 1 patient and neuroendocrine carcinoma (MIB-1: ≥21%) in 14 patients. The median period from onset of the primary lesion up to diagnosis of brain metastasis was 12.8 months. About 33% of patients had a single metastasis whereas 67% patients had multiple metastases. Brain metastasis was extirpated in 33% of patients. Stereotactic radiotherapy alone was administered in 20% of patients, and brain metastasis was favorably controlled in most of the patients with coadministration of cranial irradiation as appropriate. The median survival period from diagnosis of brain metastasis was 8.1 months.

CONCLUSION

Most of patients with brain metastasis from neuroendocrine carcinoma showed the primary lesion in the lungs, and they had multiple metastases to the liver, lymph nodes, bones, and so forth at the time of diagnosis of brain metastasis. The guidelines for accurate diagnosis and treatment of neuroendocrine carcinoma should be immediately established based on further analyses of those patients with brain metastasis.

Prognostic Value of MR Imaging Texture Analysis in Brain Non-Small Cell Lung Cancer Oligo-Metastases Undergoing Stereotactic Irradiation

BACKGROUND : Stereotactic irradiation is widely used in brain oligo-metastases treatment. The aim of this study is to evaluate the prognostic value of magnetic resonance imaging (MRI) texture analysis (TA) of brain metastases (BM) of non-small cell lung cancer (NSCLC). MATERIALS AND METHODS : This study included thirty-eight consecutive patients undergoing stereotactic irradiation, that is, stereotactic fractionated radiotherapy (SRT) or radiosurgery (SRS), from January 2011 to December 2014 for 1-2 brain BM from NSCLC. Whole-brain radiotherapy (WBRT) was not delivered. The diagnostic MRI DICOM (Digital Imaging and Communications in Medicine) images were collected and analyzed with a homemade ImageJ macro, and typical TA parameters (mean, standard deviation, skewness, kurtosis, entropy, and uniformity) were evaluated for: brain progression-free survival; modality of brain metastatic progression (local progression or/and new metastases); and overall survival, after SRT/SRS.

RESULTS

After SRT/SRS 14 patients (36.8%) experienced recurrence in the brain, with a recurrence in the irradiated site (five patients, 13.2%), new metastases (11 patients, 28.9%), local recurrence and new metastases (two patients, 5.25%). Nineteen patients (50%) died of tumor progression or other causes. Entropy and uniformity were significantly associated with local progression, whereas kurtosis was significantly associated with both local progression and new brain metastases. CONCLUSIONS : These results appear promising, since the knowledge of factors correlated with the modality of brain progression after stereotactic irradiation of brain oligo-metastatic foci of NSCLC might help in driving the best treatment in these patients (association of SRT/SRS with WBRT? Increase of SRT/SRS dose?). Our preliminary data needs confirmation in large patient series.

Phase II Study of High-Dose Pemetrexed Plus Cisplatin as First-Line Chemotherapy In the Treatment of Patients with Brain Metastases from Lung Adenocarcinoma

BACKGROUND

Brain metastases (BMs) occur in up to 40% of patients with nonsmall-cell lung cancer (NSCLC). When surgery or radiosurgery is not possible, whole-brain radiotherapy (WBRT) is the standard treatment, with a cerebral response rate of approximately 30%. Pemetrexed-based chemotherapy presents an approximately 40% response rate on brain lesions of NSCLC with brain metastases.

METHODS

This trial assessed the efficacy and safety of high-dose pemetrexed plus cisplatin in NSCLC with BMs after WBRT. Thirty-two patients with Karnofsky Performance Status ≥70 were enrolled. Patients of NSCLC with brain metastases were eligible for WBRT, which was administered at 30 Gy/10f. Thereafter, high-dose pemetrexed plus cisplatin was given up to 6 cycles. Primary end point was objective response rate (RR) and progression-free survival on BM. Secondary end points included extracerebral and overall RR, safety profile, and survival.

RESULTS

The objective cerebral RR (complete and partial response) was 68.8 % (22 of 32 patients). Extracerebral and globe RR was 37.5% and 31.3%, respectively. The median progression-free survival of BM was 13.6 months, and median overall survival was 19.1 months.

CONCLUSIONS

This modality of treatment appears to a better efficacy and a good safety of BM, as well as extracerebral. Further clinical studies are warranted.

Analyses of prognostic factors in cases of non-small cell lung cancer with multiple brain metastases

AIM

To observe the therapeutic efficacy and prognostic factors that influence survival rates in non-small cell lung cancer (NSCLC) patients with multiple brain metastases (BMs), (more than three and less than ten).

METHODS

Retrospective analyses were conducted on the clinical data of 209 NSCLC patients with multiple BMs and were admitted to our hospital between March 2007 and November 2012. All BM patients received whole-brain radiotherapy. Two hundred patients received combined chemotherapy during the treatment process; 99 received targeted drug therapy; and nine got only symptomatic and supportive treatment. Survival time was defined as the period from the start of BM therapy to the patient's death or end of the follow-up period. The Kaplan-Meier method was used to calculate the median survival time, and the 6-month, 1-, and 2-year cumulative survival rates, as well as to plot the survival curves. The patients' cultural background included their socioeconomic status, level of education, their understanding of the disease, and the degree of care and support they received from their family members. Log-rank test was employed to test the differences in the survival rates between the subgroups. Cox multivariate regression analyses were used to analyze the various factors influencing the prognoses of NSCLC with multiple BMs.

RESULTS

The follow-up duration was between 1 and 87 months. The median survival time for all BM patients was 12.1 months (95% confidence interval 9.37-14.83). The 6-month, 1-, and 2-year cumulative survival rates were 80%, 50.2%, and 10.7%, respectively. Univariate analyses revealed that the independent factors influencing survival prognoses included Karnofsky Performance Status score, control of the primary lung tumor, interval between the confirmed diagnoses of lung cancer and BM, presence of extracranial metastasis, number of chemotherapy cycles undergone, Graded Prognostic Assessment class, administration of combined targeted drug therapy, the pathological type, and the cultural backgrounds of the patients. Multivariate analyses indicated that the number of chemotherapy cycles, administration of combined drug therapy, and patients' cultural background were key independent factors influencing survival prognoses.

CONCLUSION

Active treatment of NSCLC with multiple BMs was beneficial, and the patients' cultural background had a strong influence on survival prognoses. Chemotherapy combined with targeted drug therapy could increase the patients' median and overall survival rates. The number of chemotherapy cycles undergone, administration of combined targeted drug therapy, and the cultural backgrounds of the patients had significant effects on the patients' survival prognoses.

Clinicopathological analysis in patients with neuroendocrine tumors that metastasized to the brain

Background

A neuroendocrine tumor (NET) can develop anywhere in the body, but is mainly found in the pancreas, gastrointestinal tract, and lungs. This report is a retrospective study of the clinicopathological features of NET patients with brain metastasis whose tissue diagnosis was made at our hospital.

Methods

Patients with brain metastasis evidenced by clinical records and images were accumulated among 302 patients in whom tissue diagnosis of NETs was made at our hospital between 2008 and 2013. In the patients, the primary lesion, pathological classification, pattern of metastasis, details of treatment, and outcomes were analyzed.

Results

Brain metastasis was observed in 31 patients (10.3 %). The primary lesion was in the lungs in 26 patients (83.9 %), and the mammary glands, esophagus, and uterus in 1 patient each. Primary lesions were unknown in 2 patients, including 1 patient in whom NETs were detected in the lymph nodes alone. Pathological classification of the primary lesion was NET Grade 2 (Ki-67: 3 to 20 %) in 3 patients and neuroendocrine carcinoma (NEC, Ki-67: ≥21 %) in 26 patients. The median period from onset of the primary lesion up to diagnosis of brain metastasis was 12.8 months, and the brain lesion preceded brain metastasis in 6 patients. Ten patients had a single metastasis whereas 21 patients had multiple metastases, but no characteristics were observed in their images. Brain metastasis was extirpated in 10 patients. Stereotactic radiotherapy alone was administered in 6 patients, and brain metastasis was favorably controlled in most of the patients with coadministration of cranial irradiation as appropriate. The median survival period from diagnosis of brain metastasis was 8.1 months, and the major cause of death was aggravation of the primary lesion or metastatic lesions in other organs.

Conclusion

Most of NET patients with brain metastasis showed the primary lesion of NEC in the lungs, and they had multiple metastases to the liver, lymph nodes, bones, and so forth at the time of diagnosis of brain metastasis. The guidelines for accurate diagnosis and treatment of NETs should be immediately established based on further analyses of NET patients with brain metastasis.

Lung cancer: Biology and treatment options

Lung cancer remains the leading cause of cancer mortality in men and women in the U.S. and worldwide. About 90% of lung cancer cases are caused by smoking and the use of tobacco products. However, other factors such as radon gas, asbestos, air pollution exposures, and chronic infections can contribute to lung carcinogenesis. In addition, multiple inherited and acquired mechanisms of susceptibility to lung cancer have been proposed. Lung cancer is divided into two broad histologic classes, which grow and spread differently: small-cell lung carcinomas (SCLCs) and non-small cell lung carcinomas (NSCLCs). Treatment options for lung cancer include surgery, radiation therapy, chemotherapy, and targeted therapy. Therapeutic-modalities recommendations depend on several factors, including the type and stage of cancer. Despite the improvements in diagnosis and therapy made during the past 25 years, the prognosis for patients with lung cancer is still unsatisfactory. The responses to current standard therapies are poor except for the most localized cancers. However, a better understanding of the biology pertinent to these challenging malignancies, might lead to the development of more efficacious and perhaps more specific drugs. The purpose of this review is to summarize the recent developments in lung cancer biology and its therapeutic strategies, and discuss the latest treatment advances including therapies currently under clinical investigation.

Diagnosis of Brain Metastases from Lung Cancer Using a Modified Electromagnetism like Mechanism Algorithm

Brain metastases are commonly found in patients that are diagnosed with primary malignancy on their lung. Lung cancer patients with brain metastasis tend to have a poor survivability, which is less than 6 months in median. Therefore, an early and effective detection system for such disease is needed to help prolong the patients' survivability and improved their quality of life. A modified electromagnetism-like mechanism (EM) algorithm, MEM-SVM, is proposed by combining EM algorithm with support vector machine (SVM) as the classifier and opposite sign test (OST) as the local search technique. The proposed method is applied to 44 UCI and IDA datasets, and 5 cancers microarray datasets as preliminary experiment. In addition, this method is tested on 4 lung cancer microarray public dataset. Further, we tested our method on a nationwide dataset of brain metastasis from lung cancer (BMLC) in Taiwan. Since the nature of real medical dataset to be highly imbalanced, the synthetic minority over-sampling technique (SMOTE) is utilized to handle this problem. The proposed method is compared against another 8 popular benchmark classifiers and feature selection methods. The performance evaluation is based on the accuracy and Kappa index. For the 44 UCI and IDA datasets and 5 cancer microarray datasets, a non-parametric statistical test confirmed that MEM-SVM outperformed the other methods. For the 4 lung cancer public microarray datasets, MEM-SVM still achieved the highest mean value for accuracy and Kappa index. Due to the imbalanced property on the real case of BMLC dataset, all methods achieve good accuracy without significance difference among the methods. However, on the balanced BMLC dataset, MEM-SVM appears to be the best method with higher accuracy and Kappa index. We successfully developed MEM-SVM to predict the occurrence of brain metastasis from lung cancer with the combination of SMOTE technique to handle the class imbalance properties. The results confirmed that MEM-SVM has good diagnosis power and can be applied as an alternative diagnosis tool in with other medical tests for the early detection of brain metastasis from lung cancer.

Probabilistic modeling of short survivability in patients with brain metastasis from lung cancer

The prediction of substantially short survivability in patients is extremely risky. In this study, we proposed a probabilistic model using Bayesian network (BN) to predict the short survivability of patients with brain metastasis from lung cancer. A nationwide cancer patient database from 1996 to 2010 in Taiwan was used. The cohort consisted of 438 patients with brain metastasis from lung cancer. We utilized synthetic minority over-sampling technique (SMOTE) to solve the imbalanced property embedded in the problem. The proposed BN was compared with three competitive models, namely, naive Bayes (NB), logistic regression (LR), and support vector machine (SVM). Statistical analysis showed that performances of BN, LR, NB, and SVM were statistically the same in terms of all indices with low sensitivity when these models were applied on an imbalanced data set. Results also showed that SMOTE can improve the performance of the four models in terms of sensitivity, while keeping high accuracy and specificity. Further, the proposed BN is more effective as compared with NB, LR, and SVM from two perspectives: the transparency and ability to show the relation of factors affecting brain metastasis from lung cancer; it allows decision makers to find the probability despite incomplete evidence and information; and the sensitivity of the proposed BN is the highest among all standard machine learning methods.

Gamma Knife radiosurgery for the management of cerebral metastases from non–small cell lung cancer

OBJECT

Non–small cell lung cancer (NSCLC) is the most frequent cancer that metastasizes to brain. Stereotactic radiosurgery (SRS) has become the management of choice for most patients with such metastatic tumors. Therefore, the authors endeavored to elucidate the survival and SRS outcomes for patients with NSCLC metastasis at their center.

METHODS

In this single-institution retrospective analysis, the authors reviewed their experience with NSCLC metastasis during a 10-year period from 2001 to 2010. Seven hundred twenty patients underwent Gamma Knife radiosurgery. A total of 1004 SRS procedures were performed, and 3143 tumors were treated. The NSCLC subtype was adenocarcinoma in 386 patients, squamous cell carcinoma in 111 patients, and large cell carcinoma in 34 patients. The median aggregate tumor volume was 4.5 cm3 (range 0.1–88 cm3).

RESULTS

The median survival time after diagnosis of brain metastasis from NSCLC was 12.6 months, and the median survival after SRS was 8.5 months. The 1-, 2-, and 5-year survival rates after SRS were 39%, 21%, and 10%, respectively. Postradiosurgery survival was decreased in patients treated with prior whole-brain radiation therapy compared with SRS alone (p = 0.003). Aggregate tumor volume was inversely related to survival after SRS (p < 0.001), and the histological subgroups demonstrated significant survival differences (p = 0.023). The overall local tumor control rate in the entire group was 92.8%. One hundred seventy-four patients (24%) underwent repeat SRS for new or resistant metastatic deposits.

CONCLUSIONS

Stereotactic radiosurgery is an effective means of providing local control for NSCLC metastases. Neurological function and survival benefit from serial patient monitoring and repeat SRS for new tumors.

TRIM28 and β-actin identified via nanobody-based reverse proteomics approach as possible human glioblastoma biomarkers

Malignant gliomas are among the rarest brain tumours, and they have the worst prognosis. Grade IV astrocytoma, known as glioblastoma multiforme (GBM), is a highly lethal disease where the standard therapies of surgery, followed by radiation and chemotherapy, cannot significantly prolong the life expectancy of the patients. Tumour recurrence shows more aggressive form compared to the primary tumour, and results in patient survival from 12 to 15 months only. Although still controversial, the cancer stem cell hypothesis postulates that cancer stem cells are responsible for early relapse of the disease after surgical intervention due to their high resistance to therapy. Alternative strategies for GBM therapy are thus urgently needed. Nanobodies are single-domain antigen-binding fragments of heavy-chain antibodies, and together with classical antibodies, they are part of the camelid immune system. Nanobodies are small and stable, and they share a high degree of sequence identity to the human heavy chain variable domain, and these characteristics offer them advantages over classical antibodies or antibody fragments. We first immunised an alpaca with a human GBM stem-like cell line prepared from primary GBM cultures. Next, a nanobody library was constructed in a phage-display vector. Using nanobody phage-display technology, we selected specific GBM stem-like cell binders through a number of affinity selections, using whole cell protein extracts and membrane protein-enriched extracts from eight different GBM patients, and membrane protein-enriched extracts from two established GBM stem-like cell lines (NCH644 and NCH421K cells). After the enrichment, periplasmic extract ELISA was used to screen for specific clones. These nanobody clones were recloned into the pHEN6 vector, expressed in Escherichia coli WK6, and purified using immobilised metal affinity chromatography and size-exclusion chromatography. Specific nanobody:antigen pairs were obtained and mass spectrometry analysis revealed two proteins, TRIM28 and β-actin, that were up-regulated in the GBM stem-like cells compared to the controls.

Gamma knife radiosurgery for the treatment of gynecologic malignancies metastasizing to the brain: clinical article

Gynecologic malignancies represent some of the commonest causes of cancer in the female population. Despite their overall high prevalence, gynecologic malignancies have seldom been reported to metastasize to the brain. The incidence of gynecologic cancers spreading to the brain has been rising, and the optimal management of these patients is not well defined. A retrospective analysis of patients treated over the past ten years with gamma knife radiosurgery (GKRS) for metastatic gynecologic cancer to the brain was performed. Radiographic treatment response, tumor control, metastatic disease progression and survival data were analyzed. Eight patients with ovarian cancer, six patients with endometrial cancer and two separates who carried a diagnosis of cervical cancer or leiomyosarcoma harbored metastatic disease to the brain that was treated with GKRS. The median dose to the tumor margin was 20 Gy (range 10-22 Gy), and the median maximum radiosurgical dose was 31 Gy (range 16-52.9 Gy). Tumor control was achieved in all patients who had follow up imaging studies. Patients with ovarian cancer had prolonged median survival following GKRS compared to patients with endometrial cancer (22.3 vs 8.3 months, p = 0.02). The patient with cervical cancer survived 8 months following her GKRS in the setting of metastatic brain tumor progression, whereas the patient with leiomyosarcoma passed away within several weeks of treatment secondary to disseminated extracranial primary disease. GKRS is a safe and effective means of achieving intracranial tumor control for patients with gynecologic cancer that has spread to the brain.

Whole brain radiation therapy followed by intensity-modulated boosting treatment combined with concomitant temozolomide for brain metastases from non-small-cell lung cancer

BACKGROUND

Brain metastases (BMs) represent an important cause of morbidity in patients with non-small-cell lung cancer (NSCLC) and are associated with a mean survival of <1 year. Thus, new regimens improving the outcome of these patients are urgently needed. We have evaluated the response to treatment, overall survival, disease progression, and adverse effects of a concomitant treatment with whole brain radiation therapy (WBRT) followed by intensity-modulated boosting RT (IMBRT) and temozolomide (TMZ) in patients with BMs from NSCLC.

METHODS

A total of 32 patients with no more than four BMs were enrolled in this retrospective study. Patients received 30 Gy of WBRT in 15 fractions and followed by 20 Gy of IMBRT in 10 fractions with concomitant TMZ of 75 mg/m(2)/day orally during RT and continued TMZ therapy (150-200 mg/m(2)/day for 5 days every 28 days for an additional 2-6 cycles after RT).

RESULTS

Three patients had a complete response, 9 patients had a partial response, while 15 patients had stable disease; therefore, the objective responses achieved 37.5 %. Median overall survival was 8.0 months and median time to progression was 5.5 months. Common treatment-related adverse effects (Grade ≤2) included nausea, vomiting, and asthenia. Grade 3 or worse hematologic toxicities were rare. No patient presented with gross neurocognitive dysfunction.

CONCLUSION

WBRT followed by IMBRT combined with concomitant TMZ is well tolerated, yielding an encouraging objective response rate; however, overall survival improves slightly comparing with RTOG 9508 randomized trial.

Critical appraisal of the role of gefitinib in the management of locally advanced or metastatic non-small cell lung cancer

Past studies have demonstrated that epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors can significantly improve clinical outcomes in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) and sensitive EGFR gene mutations. Gefitinib (Iressa(®)), the first oral EGFR tyrosine kinase inhibitor, has been shown to be more effective and better tolerated than chemotherapy either in first-line or second-line treatment for patients with advanced NSCLC harboring sensitive EGFR mutations. Conversely, among patients with wild-type EGFR, gefitinib is inferior to standard chemotherapy in both the first-line and second-line settings. Further, gefitinib is effective in patients with brain metastases because of its low molecular weight and excellent penetration of the blood-brain barrier. In this review, we summarize the current data from clinical trials with gefitinib and appraise its role in the management of locally advanced or metastatic NSCLC.

Modeling and predicting the occurrence of brain metastasis from lung cancer by Bayesian network: a case study of Taiwan

The Bayesian network (BN) is a promising method for modeling cancer metastasis under uncertainty. BN is graphically represented using bioinformatics variables and can be used to support an informative medical decision/observation by using probabilistic reasoning. In this study, we propose such a BN to describe and predict the occurrence of brain metastasis from lung cancer. A nationwide database containing more than 50,000 cases of cancer patients from 1996 to 2010 in Taiwan was used in this study. The BN topology for studying brain metastasis from lung cancer was rigorously examined by domain experts/doctors. We used three statistical measures, namely, the accuracy, sensitivity, and specificity, to evaluate the performances of the proposed BN model and to compare it with three competitive approaches, namely, naive Bayes (NB), logistic regression (LR) and support vector machine (SVM). Experimental results show that no significant differences are observed in accuracy or specificity among the four models, while the proposed BN outperforms the others in terms of sampled average sensitivity. Moreover the proposed BN has advantages compared with the other approaches in interpreting how brain metastasis develops from lung cancer. It is shown to be easily understood by physicians, to be efficient in modeling non-linear situations, capable of solving stochastic medical problems, and handling situations wherein information are missing in the context of the occurrence of brain metastasis from lung cancer.