Survival and neurologic outcomes in a randomized trial of motexafin gadolinium and whole-brain radiation therapy in brain metastases

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.

Hippocampal avoidance whole-brain radiotherapy with simultaneous integrated boost in lung cancer brain metastases and utility of the Hopkins verbal learning test for testing cognitive impairment in Chinese patients: a prospective phase II study

BACKGROUND

This study aimed to evaluate the efficiency of hippocampal avoidance whole-brain radiotherapy with a simultaneous integrated boost (HA-WBRT-SIB) treating brain metastases (BM) and utility of the Hopkins Verbal Learning Test-Revised (HVLT-R) (Chinese version) in Chinese lung cancer patients.

METHODS

Lung cancer patients with BM undergone HA-WBRT-SIB at our center were enrolled. Brain magnetic resonance imaging, The HVLT total learning score, and side effects were evaluated before radiotherapy and 1, 3, 6, and 12 months after radiotherapy. This study analyzed the overall survival rate, progression-free survival rate, and changes in HVLT-R immediate recall scores.

RESULTS

Forty patients were enrolled between Jan 2016 and Jan 2020. The median follow-up time was 14.2 months. The median survival, progression-free survival, and intracranial progression-free survival of all patients were 14.8 months, 6.7 months and 14.8 months, respectively. Multivariate analysis indicated that male sex and newly diagnosed stage IV disease were associated with poor overall survival and progression-free survival, respectively. HVLT-R scores at baseline and 1, 3, and 6 months after radiotherapy were 21.94 ± 2.99, 20.88 ± 3.12, 20.03 ± 3.14, and 19.78 ± 2.98, respectively. The HVLT-R scores at 6 months after radiotherapy decreased by approximately 9.8% compared with those at baseline. No grade 3 toxicities occurred in the entire cohort.

CONCLUSIONS

HA-WBRT-SIB is of efficiency and cognitive-conserving in treating Chinese lung cancer BM.

TRIAL REGISTRATION

This study was retrospectively registered on ClinicalTrials.gov in 24th Feb, 2024. The ClinicalTrials.gov ID is NCT06289023.

Evaluating the sensitivity of EQ-5D-5L in patients with brain metastases: a secondary analysis of NRG CC001

BACKGROUND

EuroQoL EQ-5D-5L is a commonly used measure of health-related quality of life in clinical trials given the use of its index score as a measure of health utilities. It is unclear whether EQ-5D-5L is sensitive to changes in neurocognitive function and progression that occur following brain radiation. This study sought to evaluate the sensitivity of EQ-5D-5L in reflecting these changes.

METHODS

A secondary analysis of NRG Oncology CC001 was performed. Mean EQ-5D-5L index and visual analog scale (VAS) score changes from baseline between groups of patients stratified by neurocognitive function and intracranial progression status were assessed. MD Anderson Symptom Inventory for brain tumor (MDASI-BT) symptom and interference items were also analyzed between groups.

RESULTS

EQ-5D-5L mean index and VAS score changes between patients who had cognitive failure and those who had preserved cognition showed no statistically significant differences at any timepoint. In contrast, VAS changes at 4 months (1.61 vs -5.13, P = .05) and 6 months (8.17 vs -0.14, P = .04) were significantly improved in the patients who survived without intracranial progression. MDASI-BT cognitive factor scores were improved in the cohort of patients with preserved neurocognitive function at 2 months (1.68 vs 2.08, P = .05) and 4 months (1.35 vs 1.83, P = .04). MDASI-BT symptom interference was significantly associated with intracranial progression at 4 months, but not with neurocognitive status.

CONCLUSION

EQ-5D-5L index and VAS scores were not sensitive to neurocognitive changes that patients experienced, but VAS scores were sensitive to progression. This study challenges the routine use of EQ-5D as a quality of life metric in brain metastases clinical trials that are focused on preventing neurocognitive dysfunction.

TRIAL REGISTRATION

NCT# 02360215.

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.

Spine Metastasis Is Associated with the Development of Brain Metastasis in Non-Small-Cell Lung Cancer Patients

Background and Objectives: The mechanisms involved in the development of brain metastasis (BM) remain elusive. Here, we investigated whether BM is associated with spine involvement in patients with non-small-cell lung cancer (NSCLC). Materials and Methods: A consecutive 902 patients with metastatic NSCLC were included from the Inha Lung Cancer Cohort. Patients with BM at diagnosis or subsequent BM development were evaluated for both spine involvement in NSCLC and anatomic proximity of BM to the cerebrospinal fluid (CSF) space. Results: At diagnosis, BM was found in 238 patients (26.4%) and bone metastasis was found in 393 patients (43.6%). In patients with bone metastasis, spine involvement was present in 280 patients. BM subsequently developed in 82 (28.9%) of 284 patients without BM at diagnosis. The presence of spine metastasis was associated with BM at diagnosis and subsequent BM development (adjusted odd ratios and 95% confidence intervals = 2.42 and 1.74-3.37, p < 0.001; 1.94 and 1.19-3.18, p = 0.008, respectively). Most patients with spine metastasis, either with BM at diagnosis or subsequent BM, showed BM lesions located adjacent (within 5mm) to the CSF space (93.8% of BM at the diagnosis, 100% of subsequent BM). Conclusions: These findings suggest that the presence of spine involvement is a risk factor for BM development in NSCLC patients with bone metastasis.

Evolution of the Management of Brain Metastases: A Bibliometric Analysis

A systematic review of the published literature was conducted to analyze the management evolution of brain metastases from different cancers. Using the keywords "brain metastasis", "brain metastases", "CNS metastasis", "CNS metastases", "phase III" AND/OR "Randomized Controlled Trial" (RCT), relevant articles were searched for on the SCOPUS database. A total of 1986 articles were retrieved, published over a 45-year period (1977-2022). Relevant articles were defined as clinical studies describing the treatment or prevention of brain metastases from any cancer. Articles on imaging, quality of life, cognitive impairment after treatment, or primary brain tumors were excluded. After a secondary analysis, reviewing the abstracts and/or full texts, 724 articles were found to be relevant. Publications significantly increased in the last 10 years. A total of 252 articles (34.8%) were published in 12 core journals, receiving 50% of the citations. The number of publications in Frontiers in Oncology, BMC Cancer, and Radiotherapy and Oncology have increased considerably over the last few years. There were 111 randomized controlled trials, 128 review articles, and 63 meta-analyses. Most randomized trials reported on brain metastases management from unselected tumors (49), lung cancer (47), or breast cancer (11). In the last 5 years (2017 to 2022), management of brain metastasis has moved on from WBRT, the use of chemotherapy, and radio-sensitization to three directions. First, Radiosurgery or Radiotherapy (SRS/SRT), or hippocampal-sparing WBRT is employed to reduce radiation toxicity. Second, it has moved to the use of novel agents, such as tyrosine kinase inhibitors (TKI) and immune checkpoint inhibitors (ICI) and third, to the use of molecularly directed therapy such as TKIs, in asymptomatic low volume metastasis, obviating the need for WBRT.

Different profiles of neurocognitive functioning in patients with brain metastases prior to brain radiotherapy

OBJECTIVE

Patients with brain metastases (BrMs) are a heterogeneous population, with almost 50% experiencing cognitive impairment before brain radiotherapy. Defining pre-radiotherapy cognitive profiles will aid in understanding of the cognitive vulnerabilities and offer valuable insight and guidance for tailoring interventions.

METHODS

The study population consisted of 58 adult patients with BrMs referred for radiotherapy. A semi-structured interview and comprehensive battery including 10 neuropsychological tests were used to assess subjective and objective cognitive performance prior to radiotherapy.

RESULTS

A majority (69%) of patients report decline in cognitive performance compared to their premorbid level (i.e. pre-cancer). Objective testing revealed memory (52%), processing speed (33%) and emotion recognition (29%) deficits were most frequent. 21% of patients had no cognitive deficits while 55% had deficits (-1.5SD) in at least two cognitive domains. Hierarchical cluster analysis based on patient deficit profiles identified four clusters: (I) no or limited cognitive deficits selectively restricted to processing speed or executive function, (II) psychomotor speed deficits, (III) memory deficits and (IV) extensive cognitive deficits including memory. No patient or clinical-related (e.g. age, number of BrMs, previous treatment) differences were found between clusters.

CONCLUSIONS

Patterns of cognitive performance in patients with BrMs are heterogeneous, with most experiencing at least some degree of neurocognitive dysfunction. We identified four meaningful cognitive clusters. Stability of these clusters over time and in different samples should be assessed to advance understanding of the cognitive vulnerability of this patient population.

Dosimetric comparison between RapidArc and HyperArc in hippocampal-sparing whole-brain radiotherapy with a simultaneous integrated boost

The HyperArc technique is known for generating high-quality radiosurgical treatment plans for intracranial lesions or hippocampal-sparing whole-brain radiotherapy (WBRT). However, there is no reported feasibility of using the HyperArc technique in hippocampal-sparing WBRT with a simultaneous integrated boost (SIB). This study aimed to compare dosimetric parameters of 2 commercially-available volumetric-modulated arc radiotherapy techniques, HyperArc and RapidArc, when using hippocampal-sparing WBRT with a SIB to treat brain metastases. Treatment plans using HyperArc and RapidArc techniques were generated retrospectively for 19 previously treated patients (1 to 3 brain metastases). The planning target volumes for the whole brain (excluding the hippocampal avoidance region; PTVWB) and metastases (PTVmet) were prescribed 25 and 45 Gy, respectively, in 10 fractions. Each plan included homogeneous and inhomogeneous delivery to the PTVmet. Dosimetric parameters for the target (conformity index [CI], homogeneity index [HI], target coverage [D95%]), and nontarget organs at risk were compared for the HyperArc and RapidArc plans. For homogeneous delivery, dosimetric parameters, including mean CI, HI, and target coverage in PTVWB and PTVmet, were superior for HyperArc than RapidArc plans (all p < 0.01). The PTVWB and PTVmet target coverage for HyperArc plans was significantly greater than for RapidArc plans (96.17% vs 93.38%, p < 0.01; 94.02% vs 92.21%, p < 0.01, respectively). HyperArc plans had significantly lower mean hippocampal Dmax and Dmin values than RapidArc plans (Dmax: 15.53 Gy vs, 16.71 Gy, p < 0.01; Dmin: 8.33 Gy vs 8.93 Gy, p < 0.01, respectively). Similarly, inhomogeneous delivery of hyperArc produced a superior target and lower hippocampal dosimetric parameters than RapidArc, except for the HI of PTVmet (all p < 0.01). HyperArc generated superior conformity and target coverage with lower hippocampal doses than RapidArc. HyperArc could be an attractive technique for hippocampal-sparing WBRT with an SIB.

Effect of whole-brain radiotherapy with platinum-based chemotherapy in non-small cell lung cancer patients with multiple metastases including brain metastases

Current guidelines recommend that cytotoxic chemotherapy be considered first in non-small cell lung cancer (NSCLC) patients with multiple metastases, and whole-brain radiotherapy (WBRT) is not initially recommended even if brain metastases are present. However, cytotoxic chemotherapeutic agents are less effective in brain metastases due to poor blood-brain barrier permeability. We investigated the effect of WBRT in combination with cytotoxic chemotherapy on survival in NSCLC patients who were EGFR, ALK, and PD-L1 negative, had an ECOG PS of 2, and had multiple metastases including brain metastases. From January 2005 to December 2018, histologically confirmed NSCLC patients who were EGFR, ALK, and PD-L1 negative, had an ECOG PS of 2, and had multiple metastases including brain metastases were included in this study. Patients were classified into two groups based on receiving WBRT prior to or concurrently with administration of first-line chemotherapeutic agents or receiving chemotherapy only. We compared intracranial progression-free survival (iPFS) and overall survival (OS). Of the 240 NSCLC patients with brain metastases at diagnosis and an ECOG PS of 2, 67 patients were EGFR, ALK, and PD-L1 negative with multiple metastases including brain metastases. Among those patients, 43 (64.2%) received WBRT prior to or concurrently with platinum-based chemotherapy. Patients who received WBRT prior to or concurrently with chemotherapy had better iPFS (7.7 months [4.8-10.6] vs. 3.5 months [2.1-4.9], p = 0.009) and OS (10.8 months [5.9-15.7] vs. 6.1 months [1.9-10.3], p = 0.038) than those who did not receive WBRT. In multivariate analyses, WBRT was significantly associated with iPFS (HR: 1.94 and 95% CI 1.11-3.40, p = 0.020) and OS (HR: 1.92 and 95% CI 1.08-3.42, p = 0.027). In NSCLC patients who are EGFR, ALK, and PD-L1 negative, have an ECOG PS of 2, and have multiple metastases including brain metastases, WBRT prior to or concurrently with chemotherapy could improve iPFS and OS. Therefore, the combination of WBRT with cytotoxic chemotherapy should be considered in these patients.

Brain Metastases: Is There Still a Role for Whole-Brain Radiation Therapy?

Whole-brain radiation therapy (WBRT) has commonly been prescribed to palliate symptoms from brain metastases, to reduce the risk of local relapse after surgical resection, and to improve distant brain control after resection or radiosurgery. While targeting micrometastases throughout the brain can be considered advantageous, the simultaneous exposure of healthy brain tissue might cause adverse events. Attempts to mitigate the risk of neurocognitive decline after WBRT include the selective avoidance of the hippocampi, among others. Besides selective dose reduction, dose escalation to boost volumes, for example, simultaneous integrated boost, aiming at increased tumor control probability is technically feasible. While up-front radiotherapy for newly diagnosed brain metastases often employs radiosurgery or other techniques targeting visible lesions only, sequential (delayed) salvage treatment with WBRT might still become necessary. In addition, the presence of leptomeningeal tumors or very widespread parenchymatous brain metastases might prompt clinicians to prescribe early WBRT.

Clinical features and molecular genetics associated with brain metastasis in suspected early-stage non-small cell lung cancer

Introduction

Regarding whether brain magnetic resonance imaging (MRI) should be routine in patients with suspected early-stage lung cancer, guideline recommendations are inconsistent. Therefore, we performed this study to evaluate the incidence of and risk factors for brain metastasis (BM) in patients with suspected early-stage non-small-cell lung cancer (NSCLC).

Methods

A review of the medical charts of consecutive NSCLC patients diagnosed between January 2006 and May 2020 was performed. We identified 1,382 NSCLC patients with clinical staging of T1/2aN0M0 (excluding BM), and investigated the incidence, clinical predictors, and prognosis of BM in the cohort. We also performed RNA-sequencing differential expression analysis using transcriptome of 8 patients, using DESeq2 package (version 1.32.0) with R (version 4.1.0).

Results

Among 1,382 patients, nine hundred forty-nine patients (68.7%) underwent brain MRI during staging, and 34 patients (3.6%) were shown to have BM. Firth's bias-reduced logistic regression showed that tumor size (OR 1.056; 95% CI 1.009-1.106, p=0.018) was the only predictor of BM, and pathologic type was not a predictor of BM in our cohort (p>0.05). The median overall survival for patients with brain metastasis was 5.5 years, which is better than previously reported in the literature. RNA-sequencing differential expression analysis revealed the top 10 significantly upregulated genes and top 10 significantly downregulated genes. Among the genes involved in BM, Unc-79 homolog, non-selective sodium leak channel (NALCN) channel complex subunit (UNC79) was the most highly expressed gene in the lung adenocarcinoma tissues from the BM group, and an in vitro assay using A549 cells revealed that the NALCN inhibitor suppressed lung cancer cell proliferation and migration.

Conclusions

Given the incidence and favorable outcome of BM in patients with suspected early-stage NSCLC, selective screening with brain MRI may be considered, especially in patients with high-risk features.

Strategies to overcome/penetrate the BBB for systemic nanoparticle delivery to the brain/brain tumor

Despite its prevalence in the management of peripheral tumors, compared to surgery and radiation therapy, chemotherapy is still a suboptimal intervention in fighting against brain cancer and cancer brain metastases. This discrepancy is mainly derived from the complicatedly physiological characteristic of intracranial tumors, including the presence of blood-brain barrier (BBB) and limited enhanced permeability and retention (EPR) effect attributed to blood-brain tumor barrier (BBTB), which largely lead to insufficient therapeutics penetrating to tumor lesions to produce pharmacological effects. Therefore, dependable methodologies that can boost the efficacy of chemotherapy for brain tumors are urgently needed. Recently, nanomedicines have shown great therapeutic potential in brain tumors by employing various transcellular strategies, paracellular strategies, and their hybrids, such as adsorptive-mediated transcytosis, receptor-mediated transcytosis, BBB disruption technology, and so on. It is compulsory to comprehensively summarize these practices to shed light on future directions in developing therapeutic regimens for brain tumors. In this review, the biological and pathological characteristics of brain tumors, including BBB and BBTB, are illustrated. After that, the emerging delivery strategies for brain tumor management are summarized into different classifications and supported with detailed examples. Finally, the potential challenges and prospects for developing and clinical application of brain tumor-oriented nanomedicine are discussed.

Use and Reporting of Patient-Reported Outcomes in Trials of Palliative Radiotherapy: A Systematic Review

IMPORTANCE

Approximately 50% of all patients with cancer have an indication for radiotherapy, and approximately 50% of radiotherapy is delivered with palliative intent, with the aim of alleviating symptoms. Symptoms are best assessed by patient-reported outcomes (PROs), yet their reliable interpretation requires adequate reporting in publications.

OBJECTIVE

To investigate the use and reporting of PROs in clinical trials of palliative radiotherapy.

EVIDENCE REVIEW

This preregistered systematic review searched PubMed/Medline, EMBASE, and the Cochrane Center Register of Controlled Trials for clinical trials of palliative radiotherapy published from 1990 to 2020. Key eligibility criteria were palliative setting, palliative radiotherapy as treatment modality, and clinical trial design (per National Institutes of Health definition). Two authors independently assessed eligibility. Trial characteristics were extracted and standard of PRO reporting was assessed in adherence to the Consolidated Standards of Reporting Trials (CONSORT) PRO extension. The association of the year of publication with the use of PROs was assessed by logistic regression. Factors associated with higher CONSORT-PRO adherence were analyzed by multiple regression. This study is reported following the PRISMA guidelines.

FINDINGS

Among 7377 records screened, 225 published clinical trials representing 24 281 patients were eligible. Of these, 45 trials (20%) used a PRO as a primary end point and 71 trials (31%) used a PRO as a secondary end point. The most prevalent PRO measures were the Numeric Rating Scale/Visual Analogue Scale (38 trials), European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire C30 (32 trials), and trial-specific unvalidated measures (25 trials). A more recent year of publication was significantly associated with a higher chance of PROs as a secondary end point (odds ratio [OR], 1.04 [95% CI, 1.00-1.07]; P = .03) but not as primary end point. Adherence to CONSORT-PRO was poor or moderate for most items. Mean (SD) adherence to the extension adherence score was 46.2% (19.6%) for trials with PROs as primary end point and 31.8% (19.8%) for trials with PROs as a secondary end point. PROs as a primary end point (regression coefficient, 9.755 [95% CI, 2.270-17.240]; P = .01), brachytherapy as radiotherapy modality (regression coefficient, 16.795 [95% CI, 5.840-27.751]; P = .003), and larger sample size (regression coefficient, 0.028 [95% CI, 0.006-0.049]; P = .01) were significantly associated with better PRO reporting per extension adherence score.

CONCLUSIONS AND RELEVANCE

In this systematic review of palliative radiotherapy trials, the use and reporting of PROs had room for improvement for future trials, preferably with PROs as a primary end point.

Thioredoxin reductase selenoproteins from different organisms as potential drug targets for treatment of human diseases

Human thioredoxin reductase (TrxR) is a selenoprotein with a central role in cellular redox homeostasis, utilizing a highly reactive and solvent-exposed selenocysteine (Sec) residue in its active site. Pharmacological modulation of TrxR can be obtained with several classes of small compounds showing different mechanisms of action, but most often dependent upon interactions with its Sec residue. The clinical implications of TrxR modulation as mediated by small compounds have been studied in diverse diseases, from rheumatoid arthritis and ischemia to cancer and parasitic infections. The possible involvement of TrxR in these diseases was in some cases serendipitously discovered, by finding that existing clinically used drugs are also TrxR inhibitors. Inhibiting isoforms of human TrxR is, however, not the only strategy for human disease treatment, as some pathogenic parasites also depend upon Sec-containing TrxR variants, including S. mansoni, B. malayi or O. volvulus. Inhibiting parasite TrxR has been shown to selectively kill parasites and can thus become a promising treatment strategy, especially in the context of quickly emerging resistance towards other drugs. Here we have summarized the basis for the targeting of selenoprotein TrxR variants with small molecules for therapeutic purposes in different human disease contexts. We discuss how Sec engagement appears to be an indispensable part of treatment efficacy and how some therapeutically promising compounds have been evaluated in preclinical or clinical studies. Several research questions remain before a wider application of selenoprotein TrxR inhibition as a first-line treatment strategy might be developed. These include further mechanistic studies of downstream effects that may mediate treatment efficacy, identification of isoform-specific enzyme inhibition patterns for some given therapeutic compounds, and the further elucidation of cell-specific effects in disease contexts such as in the tumor microenvironment or in host-parasite interactions, and which of these effects may be dependent upon the specific targeting of Sec in distinct TrxR isoforms.

Activity of Adagrasib (MRTX849) in Brain Metastases: Preclinical Models and Clinical Data from Patients with KRASG12C-Mutant Non-Small Cell Lung Cancer

PURPOSE

Patients with KRAS-mutant non-small cell lung cancer (NSCLC) with brain metastases (BM) have a poor prognosis. Adagrasib (MRTX849), a potent oral small-molecule KRASG12C inhibitor, irreversibly and selectively binds KRASG12C, locking it in its inactive state. Adagrasib has been optimized for favorable pharmacokinetic properties, including long half-life (∼24 hours), extensive tissue distribution, dose-dependent pharmacokinetics, and central nervous system penetration; however, BM-specific antitumor activity of KRASG12C inhibitors remains to be fully characterized.

EXPERIMENTAL DESIGN

A retrospective database query identified patients with KRAS-mutant NSCLC to understand their propensity to develop BM. Preclinical studies assessed physiochemical and pharmacokinetic properties of adagrasib. Mice bearing intracranial KRASG12C-mutant NSCLC xenografts (LU99-Luc/H23-Luc/LU65-Luc) were treated with clinically relevant adagrasib doses, and levels of adagrasib in plasma, cerebrospinal fluid (CSF), and brain were determined along with antitumor activity. Preliminary clinical data were collected from 2 patients with NSCLC with untreated BM who had received adagrasib 600 mg twice daily in the phase Ib cohort of the KRYSTAL-1 trial; CSF was collected, adagrasib concentrations measured, and antitumor activity in BM evaluated.

RESULTS

Patients with KRAS-mutant NSCLC demonstrated high propensity to develop BM (≥40%). Adagrasib penetrated into CSF and demonstrated tumor regression and extended survival in multiple preclinical BM models. In 2 patients with NSCLC and untreated BM, CSF concentrations of adagrasib measured above the target cellular IC50. Both patients demonstrated corresponding BM regression, supporting potential clinical activity of adagrasib in the brain.

CONCLUSIONS

These data support further development of adagrasib in patients with KRASG12C-mutant NSCLC with untreated BM. See related commentary by Kommalapati and Mansfield, p. 3179.

Adagrasib in Non-Small-Cell Lung Cancer Harboring a KRASG12C Mutation

BACKGROUND

Adagrasib, a KRAS^G12C inhibitor, irreversibly and selectively binds KRAS^G12C, locking it in its inactive state. Adagrasib showed clinical activity and had an acceptable adverse-event profile in the phase 1-1b part of the KRYSTAL-1 phase 1-2 study.

METHODS

In a registrational phase 2 cohort, we evaluated adagrasib (600 mg orally twice daily) in patients with KRAS^G12C -mutated non-small-cell lung cancer (NSCLC) previously treated with platinum-based chemotherapy and anti-programmed death 1 or programmed death ligand 1 therapy. The primary end point was objective response assessed by blinded independent central review. Secondary end points included the duration of response, progression-free survival, overall survival, and safety.

RESULTS

As of October 15, 2021, a total of 116 patients with KRAS^G12C -mutated NSCLC had been treated (median follow-up, 12.9 months); 98.3% had previously received both chemotherapy and immunotherapy. Of 112 patients with measurable disease at baseline, 48 (42.9%) had a confirmed objective response. The median duration of response was 8.5 months (95% confidence interval [CI], 6.2 to 13.8), and the median progression-free survival was 6.5 months (95% CI, 4.7 to 8.4). As of January 15, 2022 (median follow-up, 15.6 months), the median overall survival was 12.6 months (95% CI, 9.2 to 19.2). Among 33 patients with previously treated, stable central nervous system metastases, the intracranial confirmed objective response rate was 33.3% (95% CI, 18.0 to 51.8). Treatment-related adverse events occurred in 97.4% of the patients - grade 1 or 2 in 52.6% and grade 3 or higher in 44.8% (including two grade 5 events) - and resulted in drug discontinuation in 6.9% of patients.

CONCLUSIONS

In patients with previously treated KRAS^G12C -mutated NSCLC, adagrasib showed clinical efficacy without new safety signals. (Funded by Mirati Therapeutics; ClinicalTrials.gov number, NCT03785249.).

The Cognitive Effects of Radiotherapy for Brain Metastases

Brain metastases are the most common intracranial neoplasm and are seen in upwards of 10-30% of patients with cancer. For decades, whole brain radiation therapy (WBRT) was the mainstay of treatment in these patients. While WBRT is associated with excellent rates of intracranial tumor control, studies have demonstrated a lack of survival benefit, and WBRT is associated with higher rates of cognitive deterioration and detrimental effects on quality of life. In recent years, strategies to mitigate this risk, such as the incorporation of memantine and hippocampal avoidance have been employed with improved results. Furthermore, stereotactic radiosurgery (SRS) has emerged as an appealing treatment option over the last decade in the management of brain metastases and is associated with superior cognitive preservation and quality of life when compared to WBRT. This review article evaluates the pathogenesis and impact of cranial irradiation on cognition in patients with brain metastases, as well as current and future risk mitigation techniques.

Immunotherapy in advanced non-small-cell lung cancer (NSCLC) after progression on chemotherapy: real-world results from a prospective institutional cohort

Objective: To analyze the outcomes of patients receiving immunotherapy (IO) with advanced non-driver mutated non-small-cell lung cancer (NSCLC) after progression on systemic treatment. Methods: The overall survival (OS), progression-free survival (PFS) and best response to IO of 64 patients who met our inclusion criteria were analyzed. Results: Median follow-up, OS and PFS were 35.9, 7.1 and 3.2 months, respectively. On uni- and multi-variable analysis, better ECOG PS and fewer extra-thoracic metastases were associated with prolonged OS and PFS. Response to IO was associated with prolonged OS, while thoracic radiotherapy and isolated CNS involvement were associated with prolonged PFS. ECOG PS, thoracic radiotherapy and PDL1 status significantly influenced the likelihood of response to IO. Overall, 30% patients experienced any grade toxicity. Conclusion: Our results are concordant with reported trial outcomes and support the application of IO in Indian patients.

Brain metastases in patients with ovarian cancer

BACKGROUND

Brain metastasis (BM) are uncommon among women with epithelial ovarian cancer (EOC). The frequency, risk factors and clinical repercussions of BM in these patients are not well described.

METHODS

We retrospectively evaluated EOC patients treated at our center from 2002 to 2020 and assessed their clinical parameters, risk for BM development and association with overall survival (OS). This cohort has a known high frequency of BRCA mutation carriers (BRCAm) due to women of Ashkenazi Jewish descent.

RESULTS

Among 1035 EOC patients, 29 (2.8%) were diagnosed with BM. The prevalence of BRCA mutations was more common among women with BM (56.5% vs. 34.3%, p = 0.033). The BM rate in patients with BRCAm was higher than the BM rate in those with wildtype BRCA (BRCAw; 5.1% vs. 2.1%, OR = 2.6; 95% CI: 1.2-5.4, p = 0.013). Median time from diagnosis to BM and from disease recurrence to BM was longer among patients with BRCAm. Median OS was not significantly different among patients with BM versus those without BM (59.4 vs. 73.4 months, p = 0.243). After BM diagnosis, median OS was not statistically significantly different between patients with BRCAm and those with BRCAw (20.6 vs. 12.3 months, p = 0.441). Treatment with poly (ADP-ribose) polymerase inhibitors and bevacizumab had no impact on subsequent development of BM.

CONCLUSIONS

BM are rare among EOC patients. However, the risk is three-fold higher among patients with BRCAm. BM do not significantly alter OS among EOC patients. The higher rate of BM in patients with BRCAm may be related to longer OS in this subpopulation.

A Therapeutic Sheep in Metastatic Wolf's Clothing: Trojan Horse Approach for Cancer Brain Metastases Treatment

Early-stage brain metastasis of breast cancer (BMBC), due to the existence of an intact blood-brain barrier (BBB), is one of the deadliest neurologic complications. To improve the efficacy of chemotherapy for BMBC, a Trojan horse strategy-based nanocarrier has been developed by integrating the cell membrane of a brain-homing cancer cell and a polymeric drug depot. With the camouflage of a MDA-MB-231/Br cell membrane, doxorubicin-loaded poly (D, L-lactic-co-glycolic acid) nanoparticle (DOX-PLGA@CM) shows enhanced cellular uptake and boosted killing potency for MDA-MB-231/Br cells. Furthermore, DOX-PLGA@CM is equipped with naturally selected molecules for BBB penetration, as evidenced by its boosted capacity in entering the brain of both healthy and early-stage BMBC mouse models. Consequently, DOX-PLGA@CM effectively reaches the metastatic tumor lesions in the brain, slows down cancer progression, reduces tumor burden, and extends the survival time for the BMBC animal. Furthermore, the simplicity and easy scale-up of the design opens a new window for the treatment of BMBC and other brain metastatic cancers.

High-frequency irreversible electroporation brain tumor ablation: exploring the dynamics of cell death and recovery

Improved therapeutics for malignant brain tumors are urgently needed. High-frequency irreversible electroporation (H-FIRE) is a minimally invasive, nonthermal tissue ablation technique, which utilizes high-frequency, bipolar electric pulses to precisely kill tumor cells. The mechanisms of H-FIRE-induced tumor cell death and potential for cellular recovery are incompletely characterized. We hypothesized that tumor cells treated with specific H-FIRE electric field doses can survive and retain proliferative capacity. F98 glioma and LL/2 Lewis lung carcinoma cell suspensions were treated with H-FIRE to model primary and metastatic brain cancer, respectively. Cell membrane permeability, apoptosis, metabolic viability, and proliferative capacity were temporally measured using exclusion dyes, condensed chromatin staining, WST-8 fluorescence, and clonogenic assays, respectively. Both tumor cell lines exhibited dose-dependent permeabilization, with 1,500 V/cm permitting and 3,000 V/cm inhibiting membrane recovery 24 h post-treatment. Cells treated with 1,500 V/cm demonstrated significant and progressive recovery of apoptosis and metabolic activity, in contrast to cells treated with higher H-FIRE doses. Cancer cells treated with recovery-permitting doses of H-FIRE maintained while those treated with recovery-inhibiting doses lost proliferative capacity. Taken together, our data suggest that H-FIRE induces reversible and irreversible cellular damage in a dose-dependent manner, and the presence of dose-dependent recovery mechanisms permits tumor cell proliferation.

Cytotoxic and Radiosensitising Effects of a Novel Thioredoxin Reductase Inhibitor in Brain Cancers

The thioredoxin (Trx) system, a key antioxidant pathway, represents an attractive target for cancer therapy. This study investigated the chemotherapeutic and radiosensitising effects of a novel Trx reductase (TrxR) inhibitor, IQ10, on brain cancer cells and the underlying mechanisms of action. Five brain cancer cell lines and a normal cell type were used. TrxR activity and expression were assessed by insulin reduction assay and Western blotting, respectively. IQ10 cytotoxicity was evaluated using growth curve, resazurin reduction and clonogenic assays. Radiosensitivity was examined using clonogenic assay. Reactive oxygen species levels were examined by flow cytometry and DNA damage assessed by immunofluorescence. Epithelial-mesenchymal transition (EMT)-related gene expression was examined by RT-PCR array. IQ10 significantly inhibited TrxR activity but did not affect Trx system protein expression in brain cancer cells. The drug exhibited potent anti-proliferative and cytotoxic effects against brain cancer cells under both normoxic and hypoxic conditions in both 2D and 3D systems, with IC₅₀s in the low micromolar range. It was up to ~ 1000-fold more potent than temozolomide. IQ10 substantially sensitised various brain cancer cells to radiation, with such effect being due, in part, to functional inhibition of TrxR, making cells less able to deal with oxidative stress and leading to increased oxidative DNA damage. IQ10 significantly downregulated EMT-associated gene expression suggesting potential anti-invasive and antimetastatic properties. This study suggests that IQ10 is a potent anticancer agent and could be used as either a single agent or combined with radiation, to treat brain cancers.

Intracranial Metastatic Disease: Present Challenges, Future Opportunities

Intracranial metastatic disease (IMD) is a prevalent complication of cancer that significantly limits patient survival and quality of life. Over the past half-century, our understanding of the epidemiology and pathogenesis of IMD has improved and enabled the development of surveillance and treatment algorithms based on prognostic factors and tumor biomolecular characteristics. In addition to advances in surgical resection and radiation therapy, the treatment of IMD has evolved to include monoclonal antibodies and small molecule antagonists of tumor-promoting proteins or endogenous immune checkpoint inhibitors. Moreover, improvements in the sensitivity and specificity of imaging as well as the development of new serological assays to detect brain metastases promise to revolutionize IMD diagnosis. In this review, we will explore current treatment principles in patients with IMD, including the emerging role of targeted and immunotherapy in select primary cancers, and discuss potential areas for further investigation.

Effect of the simulated half leaf width of a multileaf collimator on volumetric modulated arc therapy plan quality in hippocampal avoidance whole-brain radiotherapy

Purpose

Whole‐brain radiotherapy (WBRT) is commonly used in patients with multiple brain metastases. Compared with conventional WBRT, hippocampal avoidance WBRT (HA‐WBRT) more favorably preserves cognitive function and the quality of life. The hippocampal volume is considerably small (approximately 3.3 cm³). Therefore, downsizing the leaf width of a multileaf collimator (MLC) may provide higher spatial resolution and better plan quality. Volumetric modulated arc therapy (VMAT) could simulate the half MLC leaf width through couch shifting between arcs. This study investigated changes in VMAT quality for HA‐WBRT with a simulated fine MLC leaf width.

Methods

We included 18 patients with brain metastasis. All target and avoidance structures were contoured by an experienced radiation oncologist. The prescribed dose was 30 Gy in 10 fractions. For each patient, three different treatment plans were generated for comparison: VMAT with couch‐shift, VMAT without couch‐shift, and TomoTherapy. All treatment plans fulfilled Radiation Therapy Oncology Group (RTOG) 0933 criteria for HA‐WBRT. The Wilcoxon paired signed‐rank test was used to compare different treatment plans.

Results

VMAT with couch‐shift had the better average conformity index (0.823) with statistically significant difference compared to VMAT without couch‐shift (0.810). VMAT with couch‐shift (0.219) had a more favorable average homogeneity index (HI) than did VMAT without couch‐shift (0.230), although the difference was not significant. TomoTherapy had an optimal average HI of 0.070. In terms of the hippocampus, all three treatment plans met the RTOG 0933 criteria. VMAT with couch‐shift had a lower average D_max (15.2 Gy) than did VMAT without couch‐shift (15.3 Gy, p = 0.071) and TomoTherapy (15.5 Gy, p = 0.133). The average D_100% of hippocampus was the same for both VMAT with and without couch‐shift (8.5 Gy); however, TomoTherapy had a lower average D_100% value of 7.9 Gy. The treatment delivery time was similar between VMAT with and without couch‐shift (average, 375.0 and 369.6 s, respectively). TomoTherapy required a long average delivery time of 1489.9 s.

Conclusion

The plan quality of VMAT for HA‐WBRT was improved by using the couch‐shift technique to simulate the half MLC leaf width. However, the improvement was not statistically significant except conformity index. The downsizing effect decreased with the use of the sophisticated grade of VMAT. TomoTherapy offered superior plan quality but required the longest delivery time.

Modern Radiation Therapy for the Management of Brain Metastases From Non-Small Cell Lung Cancer: Current Approaches and Future Directions

Brain metastases (BMs) represent the most frequent event during the course of Non-Small Cell Lung Cancer (NSCLC) disease. Recent advancements in the diagnostic and therapeutic procedures result in increased incidence and earlier diagnosis of BMs, with an emerging need to optimize the prognosis of these patients through the adoption of tailored treatment solutions. Nowadays a personalized and multidisciplinary approach should rely on several clinical and molecular factors like patient’s performance status, extent and location of brain involvement, extracranial disease control and the presence of any “druggable” molecular target. Radiation therapy (RT), in all its focal (radiosurgery and fractionated stereotactic radiotherapy) or extended (whole brain radiotherapy) declinations, is a cornerstone of BMs management, either alone or combined with surgery and systemic therapies. Our review aims to provide an overview of the many modern RT solutions available for the treatment of BMs from NSCLC in the different clinical scenarios (single lesion, oligo and poly-metastasis, leptomeningeal carcinomatosis). This includes a detailed review of the current standard of care in each setting, with a presentation of the literature data and of the possible technical solutions to offer a “state-of-art” treatment to these patients. In addition to the validated treatment options, we will also discuss the future perspectives on emerging RT technical strategies (e.g., hippocampal avoidance whole brain RT, simultaneous integrated boost, radiosurgery for multiple lesions), and present the innovative and promising findings regarding the combination of novel targeted agents such as tyrosine kinase inhibitors and immune checkpoint inhibitors with brain irradiation.

Zebrafish xenograft model for studying mechanism and treatment of non-small cell lung cancer brain metastasis

Background

Brain metastasis (BM) is thought to be related to the mortality and poor prognosis of non-small cell lung cancer (NSCLC). Despite promising development of NSCLC treatment, the treatment of NSCLC BM is still not optimistic due to the existence of the blood-brain barrier (BBB) that prevent drug penetration, as well as the short median survival time of the patients left for treatment. In this context, further development of quick and effective pre-clinical models is needed in NSCLC BM treatment. Here, we report a model system using zebrafish to promote the development of drugs for patients with NSCLC BM.

Methods

Three different NSCLC cell lines (H1975, A549 and H1299) were used to establish zebrafish BM models. The embryo age and cell number for injection were first optimized. Metastatic cells were observed in the brain blood vessels of zebrafish and were verified by hematoxylin-eosin (HE) staining. Then, the metastasis potentials of H1975 and A549 with manipulated microRNA-330-3p (miR-330-3p) expression were also investigated. Finally, sensitivities of H1975 and A549 to osimertinib and gefitinib were tested.

Results

This zebrafish BM model could distinguish NSCLC cell lines with different BM potential. Over-expressed miR-330-p significantly improved the BM potential of the A549 cells while knockdown miR-330-p reduced the BM ability of the H1975 cells. Both osimertinib and gefitinib showed inhibition effect in zebrafish BM model with the inhibition rate higher than 50 %. H1975 cell showed much higher sensitivity to osimertinib rather than gefitinib both in vivo and in vitro.

Conclusions

We established zebrafish brain metastasis model for studying mechanism and treatment of NSCLC BM. This study provided a useful model for NSCLC brain metastasis that could be used to study the mechanism that drive NSCLC cells to the brain as well as identify potential therapeutic options.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02173-5.

Targeting the redox imbalance in mitochondria: A novel mode for cancer therapy

Changes in reactive oxygen species (ROS) levels affect many aspects of cell behavior. During carcinogenesis, moderate ROS production modifies gene expression to alter cell function, elevating metabolic activity and ROS. To avoid extreme ROS-activated death, cancer cells increase antioxidative capacity, regulating sustained ROS levels that promote growth. Anticancer therapies are exploring inducing supranormal, cytotoxic oxidative stress levels either inhibiting antioxidative capacity or promoting excess ROS to selectively destroy cancer cells, triggering mechanisms such as apoptosis, autophagy, necrosis, or ferroptosis. This review exemplifies pro-oxidants (natural/synthetic/repurposed drugs) and their clinical significance as cancer therapies providing revolutionary approaches.

ATR Inhibitor M6620 (VX-970) Enhances the Effect of Radiation in Non-Small Cell Lung Cancer Brain Metastasis Patient-Derived Xenografts

M6620, a selective ATP-competitive inhibitor of the ATM and RAD3-related (ATR) kinase, is currently under investigation with radiation in patients with non-small cell lung cancer (NSCLC) brain metastases. We evaluated the DNA damage response (DDR) pathway profile of NSCLC and assessed the radiosensitizing effects of M6620 in a preclinical NSCLC brain metastasis model. Mutation analysis and transcriptome profiling of DDR genes and pathways was performed on NSCLC patient samples. NSCLC cell lines were assessed with proliferation, clonogenic survival, apoptosis, cell cycle, and DNA damage signaling and repair assays. NSCLC brain metastasis patient-derived xenograft models were used to assess intracranial response and overall survival. In vivo IHC was performed to confirm in vitro results. A significant portion of NSCLC patient tumors demonstrated enrichment of DDR pathways. DDR pathways correlated with lung squamous cell histology; and mutations in ATR, ATM, BRCA1, BRCA2, CHEK1, and CHEK2 correlated with enrichment of DDR pathways in lung adenocarcinomas. M6620 reduced colony formation after radiotherapy and resulted in inhibition of DNA DSB repair, abrogation of the radiation-induced G2 cell checkpoint, and formation of dysfunctional micronuclei, leading to enhanced radiation-induced mitotic death. The combination of M6620 and radiation resulted in improved overall survival in mice compared with radiation alone. In vivo IHC revealed inhibition of pChk1 in the radiation plus M6620 group. M6620 enhances the effect of radiation in our preclinical NSCLC brain metastasis models, supporting the ongoing clinical trial (NCT02589522) evaluating M6620 in combination with whole brain irradiation in patients with NSCLC brain metastases.

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.

Treatment and Prognosis of Solid and Cystic Brain Metastases in Patients with Non-Small-Cell Lung Cancer

BACKGROUND

Brain metastasis (BM) is an important factor shortening the lives of patients with lung cancer. Patients with cystic BM have seldom been reported. Here, we compared the efficacy and prognosis of different therapeutic schedules for solid BM and cystic BM in patients with non-small cell lung cancer (NSCLC).

METHODS

A retrospective study was conducted of 355 patients with pathologically confirmed stage IV NSCLC, all of whom had BM. We analyzed the clinical characteristics of these patients and the efficacy of targeted drugs and chemotherapy regimens.

RESULTS

A total of 255 patients with solid BM (cohort 1) and 33 patients with cystic BM (cohort 2) had evaluable efficacy. We evaluated these 33 patients in cohort 2. The median progression-free survival (PFS) and overall survival (OS) were 8.4 months and 23.0 months, respectively. A significant difference was observed between targeted regimens and chemotherapy treatment in terms of the PFS (12.6 months vs 6.3 months, P = 0.001) and OS (47.9 months vs 17.0 months, P = 0.007). Multivariate analyses showed that treatment regimen (chemotherapy) was a poor prognostic factor for PFS (P < 0.05). Cystic BM may be more likely to occur in patients with NSCLC with genetic mutations. A difference in prognosis was observed between patients who underwent targeted treatment and chemotherapy. A significant difference in intracranial PFS was observed between cohorts (cohort 1 vs cohort 2: 15.4 months vs 9.9 months, P = 0.015), and this advantage was clear in patients who did not receive targeted therapies (11.7 months vs 6.5 months, P = 0.003). However, the OS in patients with targeted therapies in cohort 2 was significantly longer than that in cohort 1 (23.4 months vs 47.9 months, P = 0.013).

CONCLUSION

Patients with NSCLC, particularly those who develop cystic BM, should be genetically tested as much as possible to find out more suitable drug therapies.

Radiation Therapy for Brain Metastases: A Systematic Review

PURPOSE

This evidence report synthesizes the available evidence on radiation therapy for brain metastases.

METHODS AND MATERIALS

The literature search included PubMed, EMBASE, Web of Science, Scopus, CINAHL, clinicaltrials.gov, and published guidelines in July 2020; independently submitted data, expert consultation, and contacting authors. Included studies were randomized controlled trials (RCTs) and large observational studies (for safety assessments), evaluating whole brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) alone or in combination, as initial or postoperative treatment, with or without systemic therapy for adults with brain metastases due to lung cancer, breast cancer, or melanoma.

RESULTS

Ninety-seven studies reported in 189 publications were identified, but the number of analyses was limited owing to different intervention and comparator combinations as well as insufficient reporting of outcome data. Risk of bias varied, and 25 trials were terminated early, predominantly owing to poor accrual. The combination of SRS plus WBRT compared with SRS alone or WBRT alone showed no statistically significant difference in overall survival (hazard ratio [HR], 1.09; 95% confidence interval [CI], 0.69%-1.73%; 4 RCTs) or death owing to brain metastases (relative risk [RR], 0.93; 95% CI, 0.48%-1.81%; 3 RCTs). Radiation therapy after surgery did not improve overall survival compared with surgery alone (HR, 0.98; 95% CI, 0.76%-1.26%; 5 RCTs). Data for quality of life, functional status, and cognitive effects were insufficient to determine effects of WBRT, SRS, or postsurgery interventions. We did not find systematic differences across interventions in serious adverse events, number of adverse events, radiation necrosis, fatigue, or seizures. WBRT plus systemic therapy (RR 1.44; 95% CI, 1.03%-2.00%; 14 studies) was associated with increased risks for vomiting compared with WBRT alone.

CONCLUSIONS

Despite the substantial research literature on radiation therapy, comparative effectiveness information is limited. There is a need for more data on patient-relevant outcomes such as quality of life, functional status, and cognitive effects.

Radiobiological impact of gadolinium neutron capture from proton therapy and alternative neutron sources using TOPAS-nBio

PURPOSE

A multi-scale investigation of the biological properties of gadolinium neutron capture (GdNC) therapy with applications in particle therapy is conducted using the TOPAS Monte Carlo (MC) simulation code. The simulation results are used to quantify the amount of gadolinium dose enhancement produced as a result of the secondary neutron production from proton therapy scaled by measured data.

MATERIALS AND METHODS

MC modeling was performed using the radiobiology extension TOol for PArticle Simulation TOPAS-nBio MC simulation code to study the radiobiological effects produced from GdNC on a segment of DNA, a spherical cellular model, and from the modeling of previous experimental measurements. The average RBE values were calculated from two methods, microdosimetric kinematic (MK) and biological weighting r(y) within a 2 nm DNA segment for GdNC. The single-strand breaks (SSBs) and double-strand breaks (DSBs) were calculated from within the nucleus of a 20 µm diameter, spherical cell model. From a previous experimental proton therapy measurement using a spread-out Bragg peak (SOBP) of 4.5-9.5 cm and a delivered absorbed dose of 10.4 Gy, the amount of Gd neutron captures was calculated and used to quantify the amount of GdNC absolute dose from particle therapy.

RESULTS

The average RBE from microdosimetric kinematic and biological weighting was 1.35, and 1.70 for a 10% cell survival on HSG cell-line and weighting function data from early intestinal tolerance of mice. From a central isotropic GdNC source, the energy deposition is found to decrease from roughly 2.7 eV per capture down to approximately 0.01 eV per capture, a drop of two orders of magnitude within 50 nm. This result suggests that Gd needs to be close to the DNA (within 10-20 nm) in order for neutron capture to induce a significant dose enhancement due to the short-range electrons emitted after Gd neutron capture. Within a spherical cell model, the SSBs, and DSBs were determined to be 39 and 1.5 per neutron capture, respectively. From the total neutron captures produced from an experimental proton therapy measurement on a 3000 PPM Gd solution, an insignificant absolute Gd dose enhancement was quantified to be 5.4 × 10^-6  Gy per Gy of administered proton dose.

CONCLUSION

From this study and literature review, the production of secondary thermal neutrons from proton therapy is determined to be a limiting factor and unlikely to produce a clinically useful dose enhancement for secondary neutron capture therapy. Moreover, alternative neutron sources, such as, a compact deuterium-tritium (D-T) neutron generator, a "high yield" deuterium-deuterium (D-D) generator, or an industrial strength (100 mg) ²⁵² Cf source were investigated, with the ²⁵² Cf source the most likely to be capable of producing enough neutrons for 1 Gy of localized GdNC absolute dose within a reasonable treatment time.

Radiotherapy in brain metastases from EGFR-mutated non-small cell lung cancer

Epidermal growth factor receptor (EGFR) mutations are present in 20–40% of non-small cell lung cancers (NSCLCs). Brain metastasis (BM) is more common in EGFR-mutated NSCLC (25–45%) compared to EGFR wild-type (15–30%). First and second-generation tyrosine kinase inhibitors (TKIs), such as erlotinib and afatinib have proven to be superior to chemotherapy in the front-line treatment of EGFR-mutated NSCLC. Osimertinib, a third-generation EGFR TKI, has demonstrated better blood brain barrier (BBB) penetration, higher rate of intracranial response (66% vs. 43%) and a lower rate of CNS progression when compared to first generation EGFR TKI. Evidence on upfront radiation vs. upfront osimertinib is limited, but rapidly evolving and being tested in ongoing comparative trials. Stereotactic radiation (SRS) is very effective in the control of BMs and has been increasingly used and consequently replacing resection of BMs. SRS also has been increasingly used in the treatment of multiple BMs. Considering the effectiveness of targeted agents such as third generation EGFR inhibitors clinicians now are more frequently faced with the decision, if systemic therapy is safe and effective enough to withhold SRS. Third generation EGFR inhibitors also have fewer adverse events as previous generations. This review discusses the current literature available for management of BM in EGFR-mutated NSCLC.

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.

Phase II trial of hippocampal-sparing whole brain irradiation with simultaneous integrated boost for metastatic cancer

BACKGROUND

Advanced radiotherapeutic treatment techniques limit the cognitive morbidity associated with whole-brain radiotherapy (WBRT) for brain metastasis through avoidance of hippocampal structures. However, achieving durable intracranial control remains challenging.

METHODS

We conducted a single-institution single-arm phase II trial of hippocampal-sparing whole brain irradiation with simultaneous integrated boost (HSIB-WBRT) to metastatic deposits in adult patients with brain metastasis. Radiation therapy consisted of intensity-modulated radiation therapy delivering 20 Gy in 10 fractions over 2-2.5 weeks to the whole brain with a simultaneous integrated boost of 40 Gy in 10 fractions to metastatic lesions. Hippocampal regions were limited to 16 Gy. Cognitive performance and cancer outcomes were evaluated.

RESULTS

A total of 50 patients, median age 60 years (interquartile range, 54-65), were enrolled. Median progression-free survival was 2.9 months (95% CI: 1.5-4.0) and overall survival was 9 months. As expected, poor survival and end-of-life considerations resulted in a high exclusion rate from cognitive testing. Nevertheless, mean decline in Hopkins Verbal Learning Test-Revised delayed recall (HVLT-R DR) at 3 months after HSIB-WBRT was only 10.6% (95% CI: -36.5‒15.3%). Cumulative incidence of local and intracranial failure with death as a competing risk was 8.8% (95% CI: 2.7‒19.6%) and 21.3% (95% CI: 10.7‒34.2%) at 1 year, respectively. Three grade 3 toxicities consisting of nausea, vomiting, and necrosis or headache were observed in 3 patients. Scores on the Multidimensional Fatigue Inventory 20 remained stable for evaluable patients at 3 months.

CONCLUSIONS

HVLT-R DR after HSIB-WBRT was significantly improved compared with historical outcomes in patients treated with traditional WBRT, while achieving intracranial control similar to patients treated with WBRT plus stereotactic radiosurgery (SRS). This technique can be considered in select patients with multiple brain metastases who cannot otherwise receive SRS.

Robust performance of deep learning for automatic detection and segmentation of brain metastases using three-dimensional black-blood and three-dimensional gradient echo imaging

OBJECTIVES

To evaluate whether a deep learning (DL) model using both three-dimensional (3D) black-blood (BB) imaging and 3D gradient echo (GRE) imaging may improve the detection and segmentation performance of brain metastases compared to that using only 3D GRE imaging.

METHODS

A total of 188 patients with brain metastases (917 lesions) who underwent a brain metastasis MRI protocol including contrast-enhanced 3D BB and 3D GRE were included in the training set. DL models based on 3D U-net were constructed. The models were validated in the test set consisting of 45 patients with brain metastases (203 lesions) and 49 patients without brain metastases.

RESULTS

The combined 3D BB and 3D GRE model yielded better performance than the 3D GRE model (sensitivities of 93.1% vs 76.8%, p < 0.001), and this effect was significantly stronger in subgroups with small metastases (p interaction < 0.001). For metastases < 3 mm, ≥ 3 mm and < 10 mm, and ≥ 10 mm, the sensitivities were 82.4%, 93.2%, and 100%, respectively. The combined 3D BB and 3D GRE model showed a false-positive per case of 0.59 in the test set. The combined 3D BB and 3D GRE model showed a Dice coefficient of 0.822, while 3D GRE model showed a lower Dice coefficient of 0.756.

CONCLUSIONS

The combined 3D BB and 3D GRE DL model may improve the detection and segmentation performance of brain metastases, especially in detecting small metastases.

KEY POINTS

• The combined 3D BB and 3D GRE model yielded better performance for the detection of brain metastases than the 3D GRE model (p < 0.001), with sensitivities of 93.1% and 76.8%, respectively. • The combined 3D BB and 3D GRE model showed a false-positive rate per case of 0.59 in the test set. • The combined 3D BB and 3D GRE model showed a Dice coefficient of 0.822, while the 3D GRE model showed a lower Dice coefficient of 0.756.

Efficacy and safety of treatment modalities across EGFR selected/unselected populations with non-small cell lung cancer and brain metastases: A systematic review and Bayesian network meta-analysis

OBJECTIVE

To compare the efficacy and safety of treatment modalities across different populations with non-small cell lung cancer and brain metastases.

METHODS

A comprehensive search for randomized controlled trials was conducted in databases including PubMed, Embase, the Cochrane library, the ClinicalTrials.gov, and major international conferences. The main outcomes of interest were progression-free survival, overall survival, and severe adverse events. Bayesian network meta-analytical techniques were implemented, to compare treatment modalities based on efficacy and safety profiles. The protocol for this study has been registered in the Prospective Register of Systematic Reviews (PROSPERO, CRD42020155330).

RESULTS

15 randomized controlled trials with a total of 1216 patients were analyzed. Network meta-analysis generated six comparisons both in EGFR positive and EGFR unselected populations. For patients harboring EGFR positive mutations, osimertinib appears to significantly increase progression-free survival, compared to 1st generation EGFR-TKI (HR 0.46, 95 %CI 0.38-0.55), 2nd generation EGFR-TKI (HR: 0.59, 95 %CI 0.34-0.99), conventional chemotherapy (HR 0.30, 95 %CI 0.14-0.66), radiotherapy (HR 0.20, 95 %CI 0.14-0.29), and radiotherapy plus 1st generation TKI (HR 0.21, 95 %CI 0.14-0.32). Osimertinib also appears to increase the likelihood of survival and prolong overall survival. For EGFR unselected patients, combined anti-PD1 monoclonal antibody with conventional chemotherapy appears superior to radiotherapy (HR: 0.20, 95 % CI 0.14-0.29), conventional chemotherapy (HR: 0.42, 95 %CI 0.28-0.68), radiotherapy plus conventional chemotherapy (HR: 0.59, 95 %CI 0.32-0.98), radiotherapy plus 1st generation TKI (HR:0.49, 95 %CI 0.25-0.96), and immune checkpoint inhibitors monotherapy (HR:0.44, 95 %CI 0.28-0.69). However, combination therapies are generally more toxic causing an increased number of severe adverse events, particularly when anti-PD1 monoclonal antibody is combined with conventional chemotherapy.

CONCLUSIONS

Osimertinib appears to be the most effective and safest treatment in NSCLC patients with brain metastases, harboring EGFR positive mutations. The anti-PD1 monoclonal antibody and conventional chemotherapy combination increases survival for NSCLC patients with brain metastases who were not selected according to EGFR mutation, although this increased benefit positively correlates with an increased number of severe adverse events.

An immune-related gene expression signature predicts brain metastasis in lung adenocarcinoma patients after surgery: gene expression profile and immunohistochemical analyses

Background

Lung adenocarcinoma (LUAD) with brain metastasis (BM) occurs frequently and has a poor prognosis. In this study, we aimed to assess the correlation between gene expression signatures and the development of BM after surgical resection of LUAD.

Methods

We analyzed the immune-related gene expression profiles of 72 LUADs with and without BM after surgery and verified them using NanoString method and immunohistochemistry (IHC). We matched the Tumor, Node, Metastasis (TNM) stage in the groups with and without BM to minimize the effect of TNM stage. Pathway enrichment studies were also performed.

Results

In the NanoString results, we identified 11 upregulated immune-related gene signature that correlated specifically with BM in the discovery and validation sets [area under the curve (AUC) =0.750 and 0.787, respectively]. The discovery set achieved 94% sensitivity and 62% specificity and the validation set displayed 100% sensitivity and 50% specificity. Eight out of the 11 genes were verified by IHC and had profiles similar to the gene expression profile results (AUC =0.844 for the discovery set and AUC =0.795 for the validation set). Subgroup analysis revealed that 11 immune-related gene signature enabled prediction of BM at all TNM stages. There were no differences in the 11 immune-related gene expression signatures between the primary LUAD samples and the matched brain samples. Pathway enrichment analysis revealed that the cytokine-cytokine receptor interaction pathway was closely correlated with BM.

Conclusions

The 11 identified immune-related gene expression signatures may be potentially clinically useful predictors for BM and can provide patient-specific treatment options.

Metastasis to the Central Nervous System

PURPOSE OF REVIEW

Management of metastasis to the central nervous system (CNS) has evolved, and molecular characterization of metastatic disease is now routinely done. Targeted therapies, once few in number with limited penetration into the CNS, have multiplied in number and increased in CNS coverage. This article addresses recent advances in the evaluation and clinical management of patients with CNS metastasis.

RECENT FINDINGS

Metastasis of cancer to the CNS can be diagnosed and characterized with novel techniques, including molecular analyses of the spinal fluid, so-called liquid biopsies. Resected parenchymal CNS metastases are now routinely subjected to genomic sequencing. For patients with CNS metastases displaying targetable mutations, a wide variety of treatment options are available, including deferral of radiation therapy in favor of a trial of an orally bioavailable targeted therapy or immunotherapy. For patients without a molecularly targetable lesion, local treatment in the form of radiation therapy, now most often stereotactic radiosurgery, is supplanting untargeted whole-brain radiation therapy.

SUMMARY

Technologic advances in diagnosis and management have resulted in new diagnostic and therapeutic approaches to patients with metastasis to the CNS, with resulting improvements in progression-free and overall survival.

Free Radicals as a Double-Edged Sword: The Cancer Preventive and Therapeutic Roles of Curcumin

Free radicals, generally composed of reactive oxygen species (ROS) and reactive nitrogen species (RNS), are generated in the body by various endogenous and exogenous systems. The overproduction of free radicals is known to cause several chronic diseases including cancer. However, increased production of free radicals by chemotherapeutic drugs is also associated with apoptosis in cancer cells, indicating the dual nature of free radicals. Among various natural compounds, curcumin manifests as an antioxidant in normal cells that helps in the prevention of carcinogenesis. It also acts as a prooxidant in cancer cells and is associated with inducing apoptosis. Curcumin quenches free radicals, induces antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase), and upregulates antioxidative protein markers-Nrf2 and HO-1 that lead to the suppression of cellular oxidative stress. In cancer cells, curcumin aggressively increases ROS that results in DNA damage and subsequently cancer cell death. It also sensitizes drug-resistant cancer cells and increases the anticancer effects of chemotherapeutic drugs. Thus, curcumin shows beneficial effects in prevention, treatment and chemosensitization of cancer cells. In this review, we will discuss the dual role of free radicals as well as the chemopreventive and chemotherapeutic effects of curcumin and its analogues against cancer.

Functional gadolinium-based nanoscale systems for cancer theranostics

Cancer theranostics is a new strategy for combating cancer that integrates cancer imaging and treatment through theranostic agents to provide an efficient and safe way to improve cancer prognosis. Design and synthesis of these cancer theranostic agents are crucial since these agents are required to be biocompatible, tumor-specific, imaging distinguishable and therapeutically efficacious. In this regard, several types of gadolinium (Gd)-based nanomaterials have been introduced to combine different therapeutic agents with Gd to enhance the efficacy of therapeutic agents. At the same time, the entire treatment procedure could be monitored via imaging tools due to incorporation of Gd ions, Gd chelates and Gd/other imaging probes in the theranostic agents. This review aims to overview recent advances in the Gd-based nanomaterials for cancer theranostics and perspectives for Gd nanomaterial-based cancer theranostics are provided.

Porphyrinoid Drug Conjugates

Drawing inspiration from nature today remains a time-honored means of discovering the therapies of tomorrow. Porphyrins, the so-called "pigments of life" have played a key role in this effort due to their diverse and unique properties. They have seen use in a number of medically relevant applications, including the development of so-called drug conjugates wherein functionalization with other entities is used to improve efficacy while minimizing dose limiting side effects. In this Perspective, we highlight opportunities associated with newer, completely synthetic analogs of porphyrins, commonly referred to as porphyrinoids, as the basis for preparing drug conjugates. Many of the resulting systems show improved medicinal or site-localizing properties. As befits a Perspective of this type, our efforts to develop cancer-targeting, platinum-containing conjugates based on texaphyrins (a class of so-called "expanded porphyrins") will receive particular emphasis; however, the promise inherent in this readily generalizable approach will also be illustrated briefly using two other common porphyrin analogs, namely the corroles (a "contracted porphyrin") and porphycene (an "isomeric porphyrin").

Relationship between cognitive functioning, mood, and other patient factors on quality of life in metastatic brain cancer

OBJECTIVE

Neurocognitive functioning (NCF), mood disturbances, physical functioning, and social support all share a relationship with health-related quality of life (HRQOL). However, investigations into these relationships have not been conducted in persons with brain metastases (BM).

PATIENTS AND METHODS

Ninety-three newly diagnosed persons with BM were administered various cognitive batteries. Data were collected across a wide range of categories (ie, cognitive, demographic, disease/treatment, mood, social support, physical functioning). The Functional Assessment of Cancer Treatment (FACT) scale was used to measure HRQOL.

RESULTS

Mood and physical function correlated with lower HRQOL in every measured domain. Verbal learning and memory correlated with every FACT subscale except emotional quality of life. Social support also correlated with several HRQOL domains. Stepwise linear regression revealed that mood predicted general well-being and several FACT subscales, including physical, emotional and cognitive well-being. Social support and physical health were predictive of general well-being. Verbal learning and memory predicted cognitive well-being.

CONCLUSION

HRQOL is a complex construct affected by numerous variables. In particular, mood, physical functioning, and learning and memory were important predictors of HRQOL, and clinicians are encouraged to obtain information in these areas during baseline assessments in persons with BM.

Tyrosine Kinase Inhibitor Therapy for Brain Metastases in Non-Small-Cell Lung Cancer: A Primer for Radiologists

Treatment options for patients who develop brain metastases secondary to non-small-cell lung cancer have rapidly expanded in recent years. As a key adjunct to surgical and radiation therapy options, systemic therapies are now a critical component of the oncologic management of metastatic CNS disease in many patients with non-small-cell lung cancer. The aim of this review article was to provide a guide for radiologists, outlining the role of systemic therapies in metastatic non-small-cell lung cancer, with a focus on tyrosine kinase inhibitors. The critical role of the blood-brain barrier in the development of systemic therapies will be described. The final sections of this review will provide an overview of current imaging-based guidelines for therapy response. The utility of the Response Assessment in Neuro-Oncology criteria will be discussed, with a focus on how to use the response criteria in the assessment of patients treated with systemic and traditional therapies.

Brain metastases from germ cell tumor: time to reconsider radiotherapy?

The presence of brain metastases (BMs) from germ cell tumor (GCT) remains a rare situation. BMs predominantly occur among patients with testis primary tumor site, and are almost exclusively associated with non-seminomatous (NS) histologies. Two situations must be distinguished, which differ in terms of clinical presentation, overall prognostic and management. At diagnosis, BMs are almost systematically associated with extra-cerebral metastases and the cornerstone of treatment is chemotherapy, while the role of local treatment remains controversial. In the metachronous setting, BMs more frequently constitute an isolated site of relapse, the outcome is poorer, and the role of local treatment is more consensual. However, all these data widely come from old reports, with outdated radiation techniques. The recent advances in radiation oncology, especially the rising use of stereotactic radiotherapy, could lead to the reconsideration of ancient dogmas regarding the "radiosensitivity" of (NS)GCT and the role of radiotherapy among patients with BMs.

Hippocampus-avoidance whole-brain radiation therapy with a simultaneous integrated boost for multiple brain metastases

BACKGROUND

The current study was aimed at investigating the feasibility of hippocampus-avoidance whole-brain radiation therapy with a simultaneous integrated boost (HA-WBRT+SIB) for metastases and at assessing tumor control in comparison with conventional whole-brain radiation therapy (WBRT) in patients with multiple brain metastases.

METHODS

Between August 2012 and December 2016, 66 patients were treated within a monocentric feasibility trial with HA-WBRT+SIB: hippocampus-avoidance WBRT (30 Gy in 12 fractions, dose to 98% of the hippocampal volume ≤ 9 Gy) and a simultaneous integrated boost (51 or 42 Gy in 12 fractions) for metastases/resection cavities. Intracranial tumor control, hippocampal failure, and survival were subsequently compared with a retrospective cohort treated with WBRT via propensity score matching analysis.

RESULTS

After 1:1 propensity score matching, there were 62 HA-WBRT+SIB patients and 62 WBRT patients. Local tumor control (LTC) of existing metastases was significantly higher after HA-WBRT+SIB (98% vs 82% at 1 year; P = .007), whereas distant intracranial tumor control was significantly higher after WBRT (82% vs 69% at 1 year; P = .016); this corresponded to higher biologically effective doses. Intracranial progression-free survival (PFS; 13.5 vs 6.4 months; P = .03) and overall survival (9.9 vs 6.2 months; P = .001) were significantly better in the HA-WBRT+SIB cohort. Four patients (6.5%) developed hippocampal metastases after hippocampus avoidance. The neurologic death rate after HA-WBRT+SIB was 27.4%.

CONCLUSIONS

HA-WBRT+SIB can be an efficient therapeutic option for patients with multiple brain metastases and is associated with improved LTC of existing metastases, higher intracranial PFS, a reduction of the neurologic death rate, and an acceptable risk of radiation necrosis. The therapy has the potential to prevent neurocognitive adverse effects, which will be further evaluated in the multicenter, phase 2 HIPPORAD trial.

Current approaches to the management of brain metastases

Brain metastases are a very common manifestation of cancer that have historically been approached as a single disease entity given the uniform association with poor clinical outcomes. Fortunately, our understanding of the biology and molecular underpinnings of brain metastases has greatly improved, resulting in more sophisticated prognostic models and multiple patient-related and disease-specific treatment paradigms. In addition, the therapeutic armamentarium has expanded from whole-brain radiotherapy and surgery to include stereotactic radiosurgery, targeted therapies and immunotherapies, which are often used sequentially or in combination. Advances in neuroimaging have provided additional opportunities to accurately screen for intracranial disease at initial cancer diagnosis, target intracranial lesions with precision during treatment and help differentiate the effects of treatment from disease progression by incorporating functional imaging. Given the numerous available treatment options for patients with brain metastases, a multidisciplinary approach is strongly recommended to personalize the treatment of each patient in an effort to improve the therapeutic ratio. Given the ongoing controversies regarding the optimal sequencing of the available and expanding treatment options for patients with brain metastases, enrolment in clinical trials is essential to advance our understanding of this complex and common disease. In this Review, we describe the key features of diagnosis, risk stratification and modern paradigms in the treatment and management of patients with brain metastases and provide speculation on future research directions.

Mapping distribution of brain metastases: does the primary tumor matter?

Purpose

Prior reports on the location and sizes of brain metastases almost entirely focus on patients with primary breast and pulmonary cancer. This is the first study comparing multiple other types of cancer that metastasize to the brain.

Methods

This monocentric retrospective study includes 369 untreated patients with 3313 intraaxial brain metastases. Following semi-manual segmentation of metastases on post-contrast T1WI, cumulative spatial probability distribution maps of brain metastases were created for the whole group and for all primary tumors. Furthermore, mixed effects logistic regression model analysis was performed to determine if the primary tumor, patient age, and patient sex influence lesion location.

Results

The cerebellum as location of brain metastases was proportionally overrepresented. Breast and pulmonary cancer caused higher number of brain metastases to what would normally be expected. Multivariate analyses revealed a significant accumulation of brain metastases from skin cancer in a frontal and from breast and gastrointestinal cancer in a cerebellar location.

Conclusion

Distribution of brain metastases is very heterogeneous for the distinct primaries, possibly reflecting the diversity of mechanisms involved in brain metastases formation. In daily clinical practice distribution patters may be beneficial to predict the primary cancer site, if unknown.

Electronic supplementary material

The online version of this article (10.1007/s11060-020-03419-6) contains supplementary material, which is available to authorized users.