Deciphering the causal relationship between plasma and cerebrospinal fluid metabolites and glioblastoma multiforme: a Mendelian Randomization study.

BACKGROUND: Glioblastoma Multiforme (GBM) is one of the most aggressive and fatal brain cancers. The study of metabolites could be crucial for understanding GBM's biology and reveal new treatment strategies. METHODS: The GWAS data for GBM were sourced from the FinnGen database. A total of 1400 plasma metabolites were collected from the GWAS Catalog dataset. The cerebrospinal fluid (CSF) metabolites data were collected from subsets of participants in the WADRC and WRAP studies. We utilized the inverse variance weighting (IVW) method as the primary tool to explore the causal relationship between metabolites in plasma and CSF and glioblastoma, ensuring the exclusion of instances with horizontal pleiotropy. Additionally, four supplementary analytical methods were applied to reinforce our findings. Aberrant results were identified and omitted based on the outcomes of the leave-one-out sensitivity analysis. Conclusively, a reverse Mendelian Randomization analysis was also conducted to further substantiate our results. RESULTS: The study identified 69 plasma metabolites associated with GBM. Of these, 40 metabolites demonstrated a significant positive causal relationship with GBM, while 29 exhibited a significant negative causal association. Notably, Trimethylamine N-oxide (TMAO) levels in plasma, not CSF, were found to be a significant exposure factor for GBM (OR = 3.1627, 95% CI = (1.6347, 6.1189), P = 0.0006). The study did not find a reverse causal relationship between GBM and plasma TMAO levels. CONCLUSIONS: This research has identified 69 plasma metabolites potentially associated with the incidence of GBM, among which TMAO stands out as a promising candidate for an early detectable biomarker for GBM.

Comprehensive Analysis of Blood Test Results Predicting Prognosis in Patients Undergoing Whole-brain Radiotherapy for Brain Metastases.

BACKGROUND/AIM: Blood tests, such as those included in the validated LabBM score (laboratory parameters in patients with brain metastases) predict survival after treatment of brain metastases. The model incorporates five test results [serum lactate dehydrogenase (LDH), C-reactive protein (CRP), albumin, platelets and hemoglobin]. However, many other abnormalities, albeit less well-studied, may be present in patients with metastatic cancer. Therefore, this study aimed to examine a broader range of blood tests. PATIENTS AND METHODS: This retrospective analysis included 132 patients managed with primary whole-brain radiotherapy. Additional tests, such as liver enzymes, lymphopenia, hyponatremia, and others, were also conducted. Extracranial disease extent was also analyzed. RESULTS: According to forward conditional Cox regression analyses, blood tests (albumin, hemoglobin, lymphopenia, hyponatremia) in conjunction with the number of organs affected by extracranial metastases (at least two, such as liver and bones) provided the best prognostic model. Based on these parameters, at least four prognostic strata can be assigned (median survival between 4.6 and <1 months, p=0.0001). CONCLUSION: This initial pilot study in a limited number of patients suggests that numerous blood test results may contribute to further refinement of existing prognostic models, and provides justification for additional large-scale studies.

Diagnostic and Prognostic Value of Circulating DNA Fragments in Glioblastoma Multiforme Patients.

Novel blood-circulating molecules, as potential biomarkers for glioblastoma multiforme (GBM) diagnosis and monitoring, are attracting particular attention due to limitations of imaging modalities and invasive tissue biopsy procedures. This study aims to assess the diagnostic and prognostic values of circulating cell-free DNA (cfDNA) in relation to inflammatory status in GBM patients and to determine the concentration and average size of DNA fragments typical of tumour-derived DNA fractions. Preoperative plasma samples from 40 patients (GBM 65.0 ± 11.3 years) and 40 healthy controls (HC 70.4 ± 5.4 years) were compared. The cfDNA concentrations and lengths were measured using the electrophoresis platform, and inflammatory indices (NLR, PLR, LMR, and SII) were calculated from complete blood cell analysis. More fragmented cfDNA and 4-fold higher 50-700 bp cfDNA concentrations were detected in GBM patients than in healthy controls. The average cfDNA size in the GBM group was significantly longer (median 336 bp) than in the HC group (median 271 bp). Optimal threshold values were 1265 pg/µL for 50-700 bp cfDNA (AUC = 0.857) and 290 bp for average cfDNA size (AUC = 0.814). A Kaplan-Meier survival curves analysis also demonstrated a higher mortality risk in the GBM group with a cut-off >303 bp cfDNA. This study is the first to have revealed glioblastoma association with high levels of cfDNA > 1000 pg/µL of 50-700 bp in length, which can be aggravated by immunoinflammatory reactivity.

Cathepsin F and Fibulin-1 as novel diagnostic biomarkers for brain metastasis of non-small cell lung cancer.

BACKGROUND: The lack of non-invasive methods for detection of early micro-metastasis is a major cause of the poor prognosis of non-small cell lung cancer (NSCLC) brain metastasis (BM) patients. Herein, we aimed to identify circulating biomarkers based on proteomics for the early diagnosis and monitoring of patients with NSCLC BM. METHODS: Upregulated proteins were detected by secretory proteomics in the animal-derived high brain metastatic lung cancer cell line. A well-designed study composed of three independent cohorts was then performed to verify these blood-based protein biomarkers: the serum discovery and verification cohorts (n = 80; n = 459), and the tissue verification cohort (n = 76). Logistic regression was used to develop a diagnostic biomarker panel. Model validation cohort (n = 160) was used to verify the stability of the constructed predictive model. Changes in serum Cathepsin F (CTSF) levels of patients were tracked to monitor the treatment response. Progression-free survival (PFS) and overall survival (OS) were analysed to assess their prognostic relevance. RESULTS: CTSF and Fibulin-1 (FBLN1) levels were specifically upregulated in sera and tissues of patients with NSCLC BM compared with NSCLC without BM and primary brain tumour. The combined diagnostic performance of CTSF and FBLN1 was superior to their individual ones. CTSF serum changes were found to reflect the therapeutic response of patients with NSCLC BM and the trends of progression were detected earlier than the magnetic resonance imaging changes. Elevated expression of CTSF in NSCLC BM tissues was associated with poor PFS, and was found to be an independent prognostic factor. CONCLUSIONS: We report a novel blood-based biomarker panel for early diagnosis, monitoring of therapeutic response, and prognostic evaluation of patients with NSCLC BM.

Cellular architecture of human brain metastases.

Brain metastasis (BrM) is the most common form of brain cancer, characterized by neurologic disability and an abysmal prognosis. Unfortunately, our understanding of the biology underlying human BrMs remains rudimentary. Here, we present an integrative analysis of >100,000 malignant and non-malignant cells from 15 human parenchymal BrMs, generated by single-cell transcriptomics, mass cytometry, and complemented with mouse model- and in silico approaches. We interrogated the composition of BrM niches, molecularly defined the blood-tumor interface, and revealed stromal immunosuppressive states enriched with infiltrated T cells and macrophages. Specific single-cell interrogation of metastatic tumor cells provides a framework of 8 functional cell programs that coexist or anticorrelate. Collectively, these programs delineate two functional BrM archetypes, one proliferative and the other inflammatory, that are evidently shaped through tumor-immune interactions. Our resource provides a foundation to understand the molecular basis of BrM in patients with tumor cell-intrinsic and host environmental traits.

Comparison of circulating DNA in malignant neoplasia from diverse locations: Investigating a diagnostic role.

CONTEXT: Circulating free DNA (cfDNA) analysis has emerged as novel noninvasive diagnostic biomarker in several solid tumors. Raised levels have been reported in several malignancies and may correlate with clinicopathological and treatment response. The current study was designed to assess the diagnostics of cfDNA in different tumor types of malignancies correlating with tumor (T), nodes (N), and metastases (M) stage. DESIGN: Serum samples were collected from treatment naïve cases with histologically diagnosed tumors including 23 brain tumors, 48 breasts, 50 gallbladder carcinoma (GBC), 13 lungs, 68 oral squamous cell carcinoma (OSCC), and 25 normal controls. CfDNA was quantified with real-time polymerase chain reaction (PCR), Invasive ductal carcinoma (IDC) using beta-globin gene amplification. Cut off values for diagnostics were calculated using receiver operating curve analysis. RESULTS: Contrary to other cfDNA studies where it was postulated that cfDNA would not cross the blood-brain barrier and reach the systemic circulation, we found detectable cfDNA in glioma with median (Q1-Q3) of 349.22 ng/ml (19.87-1276.58). Median cfDNA concentration in breast, gallbladder, lung, oral and normal controls was 328.72 (128.38-624.44), 778.50 (589.88-1864.35), 348.73 (194.67-483.61), 386.27 (47.88-959.67), and 74.12 (49.66-120.00), respectively. Grades I and II glioma had significantly lower levels compared to Grades III and IV (P = 0.0001). Significant difference in median cfDNA values in IDC and GBC was observed with increasing tumor grades, stage, T stage, nodal stage and metastasis and with stage of OSCC cases. CONCLUSION: CfDNA levels showed good diagnostic discrimination in glioma, GBC, breast, lung carcinoma, and OSCC. Significant increase in titers was evident with increase in cancer stage from I to IV in breast, GBC and OSCC.

Associations between tumor and edema volumes with tumor infiltrating lymphocytes in brain metastasis - A preliminary study.

OBJECTIVE: Perifocal edema of brain tumors is associated with survival and neurological symptoms. The present study sought to elucidate the association between edema volume and tumor infiltrating lymphocytes (TIL) in brain metastasis. METHODS: 25 patients with brain metastasis were included into the retrospective study. TILs expressing CD45 was analyzed with leucocyte common antigen staining. MRI was used to semiautomatically estimate tumor and edema volumes. RESULTS: No correlation between tumor volume and edema volume was identified. A positive correlation was identified between tumor volume and TILs expressing CD45 of the stromal compartment (r = 0.46, p = 0.02). No correlations were identified between TILs expressing CD45 and edema volume. CONCLUSIONS: The present study identified correlations between TILs expressing CD45 and volume of BM. The tumor growth of BM might lead to a recruitment of TIL, which could be assessed by MRI.

The von Willebrand factor stamps plasmatic extracellular vesicles from glioblastoma patients.

Glioblastoma is a devastating tumor of the central nervous system characterized by a poor survival and an extremely dark prognosis, making its diagnosis, treatment and monitoring highly challenging. Numerous studies have highlighted extracellular vesicles (EVs) as key players of tumor growth, invasiveness and resistance, as they carry and disseminate oncogenic material in the local tumor microenvironment and at distance. However, whether their quality and quantity reflect individual health status and changes in homeostasis is still not fully elucidated. Here, we separated EVs from plasma collected at different time points alongside with the clinical management of GBM patients. Our findings confirm that plasmatic EVs could be separated and characterized with standardized protocols, thereby ensuring the reliability of measuring vesiclemia, i.e. extracellular vesicle concentration in plasma. This unveils that vesiclemia is a dynamic parameter, which could be reflecting tumor burden and/or response to treatments. Further label-free liquid chromatography tandem mass spectrometry unmasks the von Willebrand Factor (VWF) as a selective protein hallmark for GBM-patient EVs. Our data thus support the notion that EVs from GBM patients showed differential protein cargos that can be further surveyed in circulating EVs, together with vesiclemia.

Incidence, and preoperative and intraoperative prognostic factors of deep venous thrombosis in patients with glioma following craniotomy.

OBJECTIVES: The aim of this study was to investigate the incidence of deep vein thrombosis (DVT) and the preoperative and intraoperative risk factors associated with DVT in glioma patients METHODS: We conducted a retrospective analysis of data obtained from glioma patients at Sanbo Hospital (Beijing, China) between 2018 and 2021. Symptomatic DVT was confirmed by Doppler ultrasonography. Multivariable logistic regression analysis was used to identify preoperative and intraoperative characteristics associated with DVT. Basic clinical variables and laboratory results were analyzed. RESULTS: A total of 492 glioma patients were included. Of these, 73 (14.84%) developed DVT, and three (0.61%) developed DVT and pulmonary embolism (PE). Multivariate analyses revealed that the following factors were highly predictive of post-operative DVT: older age ranges of 46--55 years (odds ratio [OR]: 2.94; 95% confidence interval [CI]: 1.41--6.13; p = 0.004), 56--65 years (OR: 7.86; 95% CI: 3.63--17.03; p < 0.001), and > 65 years (OR: 4.94; 95% CI: 1.83--13.33; p = 0.002); partial thromboplastin time (APTT; OR: 0.91; 95% CI: 0.84--1.00; p = 0.040); D-dimer (OR: 2.21; 95% CI: 1.28--3.82; p = 0.005); and surgery duration (OR: 2.87; 95% CI: 1.6 --5.07; p < 0.001) CONCLUSIONS: Older age, preoperative APTT, D-dimer, and surgery duration independently increased the risk of developing postoperative DVT. These findings may facilitate the development of a thrombosis risk score that will allow physicians to develop individualized strategies to prevent DVT as early as possible.

Systemic coagulation is activated in patients with meningioma and glioblastoma.

PURPOSE: Up to 30% of patients with glioblastoma (GBM) develop venous thromboembolism (VTE) over the course of the disease. Although not as high, the risk for VTE is also increased in patients with meningioma. Direct measurement of peak thrombin generation (TG) allows quantitative assessment of systemic coagulation activation in patients with GBM and meningioma. Our aim was to determine the extent of systemic coagulation activation induced by brain tumors, to measure the shift between pre- and post-operative peak TG in patients with GBM, and to assess the relationship between pre-surgical peak TG and pre-operative brain tumor volume on imaging. METHODS: Pre- and post-surgical plasma samples were obtained from successive patients with GBM and once from patients with meningioma and healthy age- and sex-matched blood donor controls. TG was measured using the calibrated automated thrombogram (CAT) assay, and tumor volumes were measured in pre-surgical MRI scans. RESULTS: Pre-surgical peak TG was higher in patients with GBM than in controls (288.6 ± 54.1 nM vs 187.1 ± 41.7 nM, respectively, P < 0.001), and, in the nine patients with GBM and paired data available, peak TG was significantly reduced after surgery (323 ± 38 nM vs 265 ± 52 nM, respectively, P = 0.007). Similarly, subjects with meningioma demonstrated higher peak TG compared to controls (242.2 ± 54.9 nM vs 177.7 ± 57.0 nM, respectively, P < 0.001). There was no association between peak TG and pre-operative tumor volume or overall survival. CONCLUSION: Our results indicate that systemic coagulation activation occurs with both meningioma and GBM, but to a greater degree in the latter. Preoperative peak TG did not correlate with tumor volume, but removal of GBM caused a significant decrease in coagulation activation.

Longitudinal Bottom-Up Proteomics of Serum, Serum Extracellular Vesicles, and Cerebrospinal Fluid Reveals Candidate Biomarkers for Early Detection of Glioblastoma in a Murine Model.

Glioblastoma Multiforme (GBM) is a brain tumor with a poor prognosis and low survival rates. GBM is diagnosed at an advanced stage, so little information is available on the early stage of the disease and few improvements have been made for earlier diagnosis. Longitudinal murine models are a promising platform for biomarker discovery as they allow access to the early stages of the disease. Nevertheless, their use in proteomics has been limited owing to the low sample amount that can be collected at each longitudinal time point. Here we used optimized microproteomics workflows to investigate longitudinal changes in the protein profile of serum, serum small extracellular vesicles (sEVs), and cerebrospinal fluid (CSF) in a GBM murine model. Baseline, pre-symptomatic, and symptomatic tumor stages were determined using non-invasive motor tests. Forty-four proteins displayed significant differences in signal intensities during GBM progression. Dysregulated proteins are involved in cell motility, cell growth, and angiogenesis. Most of the dysregulated proteins already exhibited a difference from baseline at the pre-symptomatic stage of the disease, suggesting that early effects of GBM might be detectable before symptom onset.

Myelin-associated proteins are potential diagnostic markers in patients with primary brain tumour.

INTRODUCTION: Taking into account the possibility of myelin-associated proteins having a role in brain tumour development, the study aimed to evaluate the diagnostic usefulness of myelin-associated proteins (Nogo-A, MAG, OMgp) released into extracellular space in patients with brain tumours. PATIENTS AND METHODS: Protein concentration in primary brain tumour (n = 49) and non-tumoural subjects (n = 24) was measured in cerebrospinal fluid (CSF) and serum by means of ELISA. Immunohistochemistry for IDH1-R132H was done on 5-µm thick formalin-fixed, paraffin-embedded tumour sections with the use of an antibody specific for the mutant IDH1-R132H protein. RESULTS: The receiver operator characteristic curve analysis showed that CSF Nogo-A and serum MAG were useful in differentiating patients with primary brain tumour from non-tumoural individuals. This was also true in the case of the separate analysis of the astrocytic tumour versus non-tumoural groups and the meningeal tumour versus non-tumoural groups. Neither Nogo-A nor MAG or OMgp concentrations were significantly different, in serum or CSF, between IDH1 wild-type astrocytic brain tumour patients compared to IDH1 mutant patients. CONCLUSIONS: Our results indicated the potential usefulness of CSF Nogo-A and serum MAG evaluation as circulating biomarkers of primary brain tumours. Because blood is relatively easy to obtain, future research should be conducted to explicitly indicate the value of serum MAG concentration evaluation as a brain tumour biomarker.Key messagesMyelin-associated proteins may be circulating brain tumour biomarkers.Nogo-A and MAG proteins seem to be the most useful in brain tumour diagnosis.Decreased CSF Nogo-A concentration is an adverse prognostic factor for patients' survival.

Pretreatment neutrophil-to-lymphocyte/monocyte-to-lymphocyte ratio as prognostic biomarkers in glioma patients.

OBJECTIVES: To evaluate the ability for pre-treatment NLR and MLR to predict overall survival (OS) and modified Rankin Scale (mRS) and to explore their relationship with clinicopathological parameters. METHODS: Retrospective analysis of pretreatment NLR and MLR from 64 glioma patients. RESULTS: Higher pretreatment NLR (>4.7) predicted higher mean admission mRS (p < 0.001) and 6-month mRS (p = 0.02). Higher pretreatment MLR (>0.35) was a risk factor for poorer OS in glioma patients (p = 0.024). Higher pretreatment NLR was significantly associated with larger tumor diameter (p = 0.02). CONCLUSION: NLR and MLR can serve as prognostic markers to predict functional outcomes and OS in glioma patients.

Myelin oligodendrocyte glycoprotein (MOG) antibodies in a patient with glioblastoma: Red flags for false positivity.

We present a patient with positive medium titer MOG-IgG and progressive neurological decline whose clinical and radiological phenotype were not consistent with a MOG-IgG associated disorder and ultimately received a diagnosis of glioblastoma after brain biopsy and died 4 weeks later. This represents an important topic with a high frequency of MOG-IgG testing in clinical practice. Due to this there are increasing reports of MOG-IgG positivity in atypical clinical phenotypes, raising the possibility of false positives, which can have important implications. It is important to highlight that judicious clinical evaluation is needed when interpreting MOG-IgG results in atypical settings.

Glioblastoma signature in the DNA of blood-derived cells.

Current approach for the detection of cancer is based on identifying genetic mutations typical to tumor cells. This approach is effective only when cancer has already emerged, however, it might be in a stage too advanced for effective treatment. Cancer is caused by the continuous accumulation of mutations; is it possible to measure the time-dependent information of mutation accumulation and predict the emergence of cancer? We hypothesize that the mutation history derived from the tandem repeat regions in blood-derived DNA carries information about the accumulation of the cancer driver mutations in other tissues. To validate our hypothesis, we computed the mutation histories from the tandem repeat regions in blood-derived exomic DNA of 3874 TCGA patients with different cancer types and found a statistically significant signal with specificity ranging from 66% to 93% differentiating Glioblastoma patients from other cancer patients. Our approach and findings offer a new direction for future cancer prediction and early cancer detection based on information derived from blood-derived DNA.

Perioperative Glycemia Management in Patients Undergoing Craniotomy for Brain Tumor Resection: A Global Survey of Neuroanesthesiologists' Perceptions and Practices.

OBJECTIVE: There is a paucity of clinical evidence that guides perioperative glycemia management in patients undergoing craniotomy for brain tumor resection. The purpose of this study was to better understand global perceptions and practices related to glycemia management in these patients. METHODS: Neuroanesthesiologists throughout North America, South America, Europe, and Asia filled out a brief online questionnaire related to their perceptions and practices regarding glycemia management in patients undergoing craniotomy for brain tumor resection. RESULTS: Over 4 weeks, 435 participants practicing in 34 countries across 6 continents participated in this survey. Although responders in North America were found to perceive a higher risk hyperglycemia compared with those practicing in European (P = 0.024) and South Asian (P = 0.007) countries, responders practicing in South Asian countries (P = 0.030), Middle Eastern countries (P = 0.029), and South American (P = 0.005) countries were more likely than those from North America to remeasure glucose after an initial normal glucose measurement at incision. Responders from North America reported that a higher blood glucose threshold was necessary for them to delay or cancel the surgery compared with responders in Slavic (P < 0.001), European (P = 0.002), South American (P = 0.002), and Asian and Pacific (P < 0.001) countries. Responders from North America were more likely to report that they would delay or cancel the surgery because of a higher blood glucose threshold. CONCLUSIONS: Our survey results suggest that perceptions and practices related to blood glucose management in patients undergoing brain tumor resection are variable. This study highlights the need for stronger clinical evidence and guidelines to help guide decisions for when and how to manage blood glucose derangements in these patients.

Preoperative serum lactate dehydrogenase level predicts progression and prognosis in patients with glioma.

BACKGROUND: To evaluate the value of serum Lactate Dehydrogenase (LDH) level in predicting recurrence and the overall survival (OS) of glioma patients. MATERIALS AND METHODS: A total number of 216 patients with glioma in our institution were retrospectively recruited to analyze the relationship between preoperative serum LDH level and prognosis. RESULTS: Overall, the median age of patients was 46.0 (31.0-57.0) years old; 53.7% (116 of 216) of the enrolled patients were male. Multivariate analysis revealed that serum LDH level (odds ratio [OR] = 0.97, 95% confidence interval [CI] = 0.96-0.98, P < 0.001) and World Health Organization (WHO) grade (grade II: OR = 19.64, 95%CI = 5.56-69.35, P < 0.001; grade III: OR =1 9.50, 95%CI = 7.08-53.73, P < 0.001; grade IV: OR = 15.23, 95%CI = 4.94-46.97, P < 0.001) were significant and independent of 1-year Progression-free survival (PFS) after adjusting for confounders. The predictive performance of serum LDH level was represented with area under curve (AUC) = 0.741, 95%CI = 0.677-0.798. Multivariate Cox analysis revealed that LDH level (hazard ratio [HR] = 2.56, 95%CI = 1.59-4.15, P < 0.001) and WHO grade (grade II: HR = 4.58, 95%CI = 0.56-37.23, P = 0.155; grade III: HR = 16.35, 95%CI = 2.16-123.80, P = 0.007; grade IV: HR = 42.13, 95%CI = 5.83-304.47, P < 0.001) remained associated with survival at 2-year follow-up. At 3-year follow-up, lymphocyte count (HR = 0.68, 95%CI = 0.51-0.91, P = 0.008), LDH level (HR = 2.21, 95%CI = 1.40-3.49, P = 0.001), and WHO grade (grade II: HR = 1.44, 95%CI = 0.44-4.68, P = 0.543; grade III: HR = 4.99, 95%CI = 1.68-14.87, P = 0.004; grade IV: HR = 16.96, 95%CI = 6.13-46.93, P < 0.001) remained associated with survival in multivariate Cox analysis. CONCLUSION: Our study demonstrated that preoperative serum LDH level could serve as a reliable indicator for predicting prognosis of glioma patients. Further multicenter studies are still required to verify our findings.

Novel Concepts of Glioblastoma Therapy Concerning Its Heterogeneity.

Although treatment outcomes of glioblastoma, the most malignant central nervous system (CNS) tumor, has improved in the past decades, it is still incurable, and survival has only slightly improved. Advances in molecular biology and genetics have completely transformed our understanding of glioblastoma. Multiple classifications and different diagnostic methods were made according to novel molecular markers. Discovering tumor heterogeneity only partially explains the ineffectiveness of current anti-proliferative therapies. Dynamic heterogeneity secures resistance to combined oncotherapy. As tumor growth proceeds, new therapy-resistant sub clones emerge. Liquid biopsy is a new and promising diagnostic tool that can step up with the dynamic genetic change. Getting a 'real-time' picture of a specific tumor, anti-invasion and multi-target treatment can be designed. During invasion to the peri-tumoral brain tissue, glioma cells interact with the extracellular matrix components. The expressional levels of these matrix molecules give a characteristic pattern, the invasion spectrum, which possess vast diagnostical, predictive and prognostic information. It is a huge leap forward combating tumor heterogeneity and searching for novel therapies. Using the invasion spectrum of a tumor sample is a novel tool to distinguish between histological subtypes, specifying the tumor grades or different prognostic groups. Moreover, new therapeutic methods and their combinations are under trial. These are crucial steps towards personalized oncotherapy.

Associations Between ADC Texture Analysis and Tumor Infiltrating Lymphocytes in Brain Metastasis - A Preliminary Study.

BACKGROUND/AIM: Tumor infiltrating lymphocytes (TILs) are an important prognostic factor in brain metastasis (BM). This study elucidated associations between apparent diffusion coefficient (ADC) texture analysis and TIL in BM. PATIENTS AND METHODS: Eleven patients with BM were retrospectively included into the study. TIL levels were analyzed with Leucocyte-common antigen staining. Clinical routine magnetic resonance imaging was used to calculate the texture features. RESULTS: ADC GrayLevelNonUniformity correlated with TILs of the stromal compartment (r=0.67, p=0.02). ADC HighGrayLevelRunEmphasis and ADC Coarseness showed associations with TILs of the tumoral compartment (r=-0.60, p=0.04 and r=0.68, p=0.02, respectively). CONCLUSION: ADC texture features correlated with TIL levels in BM. ADC texture features could aid in reflecting the complex tumor-micromilieu in a non-invasive manner.