Diffuse gliomas comprise the most common malignant brain tumors in adults and include glioblastomas (GBM) and World Health Organization (WHO) grade II and grade III tumors, sometimes referred to as lower-grade gliomas (LGGs). Genetic tumor profiling is used for disease classification and to guide therapy 1 , 2 , but involves brain surgery for tissue collection and repeated tumor biopsies may be necessary for accurate genotyping over the course of the disease 3 – 10 . While detection of circulating tumor DNA (ctDNA) in blood remains challenging for patients with primary brain tumors 11 , 12 , sequencing of cerebrospinal fluid (CSF) ctDNA may provide an alternative to genotype glioma at lower morbidity and cost 13 , 14 . We therefore evaluated the representation of the glioma genome in CSF from 85 glioma patients who underwent a lumbar puncture for evaluation of neurological signs or symptoms. Tumor-derived DNA was detected in CSF from 42/85 (49.4 %) patients and was associated with disease burden and adverse outcome. The genomic landscape of glioma in CSF contained a broad spectrum of genetic alterations and closely resembled the genome in tumor biopsies. Alterations that occur early during tumorigenesis, such as co-deletion of chromosome arms 1p and 19q (1p/19q codeletion) and mutations in the metabolic genes isocitrate dehydrogenase 1 (IDH1) or IDH2 1 , 2 , were shared in all matched ctDNA-positive CSF/tumor pairs, whereas we observed considerable evolution in growth factor receptor signaling pathways. The ability to monitor evolution of the glioma genome through a minimally invasive technique could advance the clinical development and use of genotype-directed therapies for glioma, one of the most aggressive human cancers.

The objective of this study was to examine the pathophysiology of ischemic stroke with cancer. Methods: We conducted a prospective cross-sectional study from 2016 to 2020 at 2 hospitals. We enrolled 3 groups of 50 adult participants each. The main group included patients with active solid tumor cancer and acute ischemic stroke. The control groups included patients with acute ischemic stroke only or active cancer only. The patients with stroke-only and patients with cancer-only were matched to the patients with cancer-plus-stroke by age, sex, and cancer type, if applicable. The outcomes were prespecified hematological biomarkers and transcranial Doppler microemboli detection. Hematological biomarkers included markers of coagulation (D-dimer and thrombin-antithrombin), platelet function (P-selectin), and endothelial integrity (thrombomodulin, soluble intercellular adhesion molecule-1 [sICAM-1], and soluble vascular cell adhesion molecule-1 [sVCAM-1]). Hematological biomarkers were compared between groups using the Kruskal-Wallis and Wilcoxon Rank-Sum tests. In multivariable linear regression models, we adjusted for race, number of stroke risk factors, smoking, stroke severity, and antithrombotic use. Transcranial Doppler microemboli presence was compared between groups using chi-square tests.Results: Levels of all study biomarkers were different between groups. In univariate between-group comparisons, patients with cancer-plus-stroke had higher levels of D-dimer, sICAM-1, sVCAM-1, and thrombomodulin than both control groups; higher levels of thrombin-antithrombin than patients with cancer-only; and higher levels of P-selectin than patients with stroke-only. Findings were similar in multivariable analyses. Transcranial Doppler microemboli were detected in 32% of patients with cancer-plus-stroke, 16% of patients with stroke-only, and 6% of patients with canceronly (p = 0.005). Interpretation: Patients with cancer-related stroke have higher markers of coagulation, platelet, and endothelial dysfunction, and more circulating microemboli, than matched controls.

Background Improvements in detection and molecular characterization of leptomeningeal metastasis from lung cancer (LC-LM) coupled with cerebrospinal fluid (CSF)-penetrating targeted therapies have altered disease management. A barrier to formal study of these therapies in LM is quantification of disease burden. Also, outcomes of patients with targetable mutations in LC-LM are not well defined. This study employs molecular and radiographic measures of LM disease burden and correlates these with outcome. Methods We reviewed charts of 171 patients with LC-LM treated at Memorial Sloan Kettering. A subset had MRI and CSF studies available. Radiographic involvement (n = 76) was scored by number of gadolinium-enhancing sites in 8 locations. CSF studies included cytopathology, circulating tumor cell (CTC) quantification (n = 16), and cell-free DNA (cfDNA) analysis (n = 21). Clinical outcomes were compared with Kaplan–Meier log-rank test and Cox proportional hazards methodologies. Results Median overall survival was 4.2 months (95% CI: 3.6–4.9); 84 patients (49%) harbored targetable mutations. Among bevacizumab-naïve patients with MRI and CSF cytology at time of LC-LM diagnosis, extent of radiographic involvement correlated with risk of death (hazard ratio [HR]: 1.16; 95% CI: 1.02–1.33; P = 0.03), as did CSF CTC (HR: 3.39, 95% CI: 1.01–11.37; P = 0.048) and CSF cfDNA concentration (HR: 2.58; 95% CI: 0.94–7.05; P = 0.06). Those without a targetable mutation were almost 50% more likely to die (HR: 1.49; 95% CI: 1.06–2.11; P = 0.02). Conclusions Extent of radiographic involvement and quantification of CSF CTC and cfDNA show promise as prognostic indicators. These findings support molecular characterization and staging for clinical management, prognostication, and clinical trial stratification of LC-LM.

Purpose The CellSearch® system has been used to identify circulating tumor cells (CTCs) in cerebrospinal fluid (CSF) to diagnose leptomeningeal metastasis (LM) in patients with epithelial cancers. Using this system, we prospectively explored sequential CSF CTC enumeration in patients with LM from HER2+ cancers receiving intrathecal (IT) trastuzumab to capture dynamic changes in CSF CTC enumeration. Methods CSF from patients enrolled in an IRB-approved phase I/II dose escalation trial of IT trastuzumab for LM in HER2+ cancer (NCT01325207) was obtained on day 1 of each cycle and was evaluated by the CellSearch® platform for CTC enumeration. The results were correlated with CSF cytology from the same sample, along with clinical and radiographic response. Results Fifteen out of 34 patients with HER2+ LM were enrolled in CSF CTC analysis; 14 were women. Radiographic LM was documented in 14 (93%) patients; CSF cytology was positive in 6 (40%) and CSF CTCs were identified in 13 (87%). Median CSF CTC was 22 CTCs (range 0-200 +) per 3 ml. HER2/neu expression analysis of CTCs was performed in 8 patients; 75% had confirmed expression of HER2/neu positivity in CSF and HER2/neu expression was absent in 25%. Four of 10 patients received 7 or more cycles of IT trastuzumab; in 3 of these patients, increase in CSF CTCs enumeration from baseline was detected 2-3 months prior to changes seen on MRI, and while CSF cytology remained negative. Conclusion Our study demonstrates that enumeration of CSF CTCs may provide dynamic, quantitative assessment of tumor burden in the central nervous system compartment during treatment for LM and prior to changes on MRI or CSF cytology. Trial Registration: Clinicaltrials.gov: NCT01325207; registered March 29th, 2011.