Recurrence of glioblastoma is associated with elevated microvascular transit time heterogeneity and increased hypoxia

Dynamic susceptibility contrast (DSC) perfusion MRI provide information about differences in macro- and microvasculature when executed with gradient-echo (GE; sensitive to macrovasculature) and spin-echo (SE; sensitive to microvasculature) contrast. This study investigated whether there are differences between macro- and microvascular transit time heterogeneity (MVTH and µVTH) and tissue oxygen tension (PO2_mit) in newly-diagnosed and recurrent glioblastoma. Fifty-seven patients with glioblastoma (25 newly-diagnosed/32 recurrent) were examined with GE- and SE-DSC perfusion sequences, and a quantitative blood-oxygen-level-dependent (qBOLD) approach. Maps of MVTH, µVTH and coefficient of variation (MCOV and µCOV) were calculated from GE- and SE-DSC data, respectively, using an extended flow-diffusion equation. PO2_mit maps were calculated from qBOLD data. Newly-diagnosed and recurrent glioblastoma showed significantly lower ( P ≤ 0.001) µCOV values compared to both normal brain and macrovasculature (MCOV) of the lesions. Recurrent glioblastoma had significantly higher µVTH ( P = 0.014) and µCOV ( P = 0.039) as well as significantly lower PO2_mit values ( P = 0.008) compared to newly-diagnosed glioblastoma. The macrovasculature, however, showed no significant differences. Our findings provide evidence of microvascular adaption in the disorganized tumor vasculature for retaining the metabolic demands in stress response of therapeutically-uncontrolled glioblastomas. Thus, µVTH and PO2_mit mapping gives insight into the tumor microenvironment (vascular and hypoxic niches) responsible for therapy resistance.

Vascular Hysteresis Loops and Vascular Architecture Mapping in Patients with Glioblastoma treated with Antiangiogenic Therapy

In this study, we investigated the variability of vascular hysteresis loop (VHL) shapes and the spatial heterogeneity of neovascularization and microvascular alterations using vascular architecture mapping (VAM) in patients with recurrent glioblastoma during bevacizumab mono-therapy. VAM data were acquired in 13 patients suffering from recurrent glioblastoma prior to and 3 months after bevacizumab treatment onset using a dual contrast agent injections approach as part of routine MRI. Two patients were additionally examined after the first cycle of bevacizumab to check for early treatment response. VHLs were evaluated as biomarker maps of neovascularization activity: microvessel type indicator (MTI) and curvature (Curv) of the VHL-long-axis. Early response to bevacizumab was dominated by reduction of smaller microvasculature (around 10 µm). In the 3-month follow-up, responding tumors additionally showed a reduction in larger microvasculature (>20 µm). VAM biomarker images revealed spatially heterogeneous microvascular alterations during bevacizumab treatment. Responding, non-responding, progressive, and remote-progressive tumor areas were observed. MTI may be useful to predict responding and non-responding tumor regions, and Curv to assess severity of vasogenic edema. Analysis of VHLs in combination with VAM biomarkers may lead to a new perspective on investigating the spatial heterogeneity of neovascularization and microvascular alterations in glioblastoma during antiangiogenic therapy.

Magnetic resonance imaging biomarkers for clinical routine assessment of microvascular architecture in glioma

Knowledge about the topological and structural heterogeneity of the microvasculature is important for diagnosis and monitoring of glioma. A vessel caliber and type-dependent temporal shift in the magnetic resonance imaging signal forms the basis for vascular architecture mapping. This study introduced a clinically feasible approach for assessment of vascular pathologies in gliomas using vascular architecture mapping. Sixty consecutive patients with known or suspected gliomas were examined using vascular architecture mapping as part of the routine magnetic resonance imaging protocol. Maps of microvessel radius and density, which adapted to the vasculature-dependent temporal shift phenomenon, were calculated using a costume-made software tool. Microvessel radius and density were moderately to severely elevated in a heterogeneous, inversely correlated pattern within high-grade gliomas. Additionally, three new imaging biomarkers were introduced: Microvessel type indicator allowing differentiation between supplying arterial and draining venous microvasculature in high-grade gliomas. Vascular-induced bolus peak time shift may presumably be sensitive for early neovascularization in the infiltration zone. Surprisingly, curvature showed significant changes in peritumoral vasogenic edema which correlated with neovascularization in the tumor core of high-grade gliomas. These new magnetic resonance imaging biomarkers give insights into complexity and heterogeneity of vascular changes in glioma; however, histological validations in more well-defined patient populations are required.

MR Imaging-derived Oxygen Metabolism and Neovascularization Characterization for Grading and IDH Gene Mutation Detection of Gliomas

Purpose To explore the diagnostic performance of physiological magnetic resonance (MR) imaging of oxygen metabolism and neovascularization activity for grading and characterization of isocitrate dehydrogenase (IDH) gene mutation status of gliomas. Materials and Methods This retrospective study had institutional review board approval; written informed consent was obtained from all patients. Eighty-three patients with histopathologically proven glioma (World Health Organization [WHO] grade II-IV) were examined with quantitative blood oxygen level-dependent imaging and vascular architecture mapping. Biomarker maps of neovascularization activity (microvessel radius, microvessel density, and microvessel type indicator [MTI]) and oxygen metabolism (oxygen extraction fraction [OEF] and cerebral metabolic rate of oxygen [CMRO₂]) were calculated. Receiver operating characteristic analysis was used to determine diagnostic performance for grading and detection of IDH gene mutation status. Results Low-grade (WHO grade II) glioma showed areas with increased OEF (+18%, P < .001, n = 20), whereas anaplastic glioma (WHO grade III) and glioblastoma (WHO grade IV) showed decreased OEF when compared with normal brain tissue (-54% [P < .001, n = 21] and -49% [P < .001, n = 41], respectively). This allowed clear differentiation between low- and high-grade glioma (area under the receiver operating characteristic curve [AUC], 1) for the patient cohort. MTI had the highest diagnostic performance (AUC, 0.782) for differentiation between gliomas of grades III and IV among all biomarkers. CMRO₂ was decreased (P = .037) in low-grade glioma with a mutated IDH gene, and MTI was significantly increased in glioma grade III with IDH mutation (P = .013) when compared with the IDH wild-type counterparts. CMRO₂ showed the highest diagnostic performance for IDH gene mutation detection in low-grade glioma (AUC, 0.818) and MTI in high-grade glioma (AUC, 0.854) and for all WHO grades (AUC, 0.899) among all biomarkers. Conclusion MR imaging-derived oxygen metabolism and neovascularization characterization may be useful for grading and IDH mutation detection of gliomas and requires only 7 minutes of extra imaging time. ^© RSNA, 2016 Online supplemental material is available for this article.

Predictive value of ABCD2 and ABCD3-I scores in TIA and minor stroke in the stroke unit setting

OBJECTIVE

It is not clear whether risk scores for early stroke recurrence after TIA that have been mainly established in outpatient and emergency department settings are valid on the background of highly specialized stroke unit care.

METHODS

ABCD2 and ABCD3-I scores have been prospectively documented in a cohort of patients admitted to Austrian stroke units within 24 hours of symptom onset with TIA or minor stroke (NIH Stroke Scale score <4).

RESULTS

A total of 5,237 TIA and minor stroke patients met inclusion criteria, with 3-month follow-up data available on 2,457. Early and 3-month stroke were observed in 2.4% and 4.2% of the study population. The probability of early stroke during the stroke unit stay (median 2 [interquartile range 1-3] days) steadily increased from 0% to 4.8% and 0% to 16.7% with increasing ABCD2 and ABCD3-I score points, respectively. On 3-month follow-up, stroke risk increased from 0% to 8.0% and 0% to 23.8% with increasing ABCD2 and ABCD3-I score points, respectively. Of the individual score components, age, blood pressure, and diabetes were not related to early or 3-month stroke, whereas clinical presentation (C), symptom duration (D), and cerebral as well as carotid imaging (I) were and accounted for the information provided by the full scores.

CONCLUSIONS

Standard ABCD2 and ABCD3-I scores are useful instruments to estimate the probability of early and 3-month stroke in TIA and minor stroke patients treated at specialized stroke units, with C, D, and I being the most important score components in this setting.

Familial Hemiplegic Migraine: Follow-up Findings of Diffusion-Weighted Magnetic Resonance Imaging (MRI), Perfusion-MRI and [99mTc] HMPAO-SPECT in a Patient with Prolonged Hemiplegic Aura

Familial hemiplegic migraine (FHM) is a rare inherited autosomal dominant disorder. Migraine aura may last up to several weeks and then resolve without sequel. We report a 21-year-old male with FHM since the age of 3 years. Diffusion-weighted magnetic resonance imaging (DWI), perfusion-MR imaging (P-MRI) and [99mTc] hexamethyl-propyleneamine-oxime-single photon emission tomography (HMPAO-SPECT) were performed on day 2, when he was somnolent with right-sided hemiplegia, on day 9 when a mild hemiparesis was still present and on day 24 after recovery. The right central region showed normal findings in DWI, whereas P-MRI and SPECT revealed hyperperfusion on day 2, less marked on day 9, and normal findings on day 24. In conclusion, this case report indicates for the first time, by means of SPECT, P-MRI and DWI studies, that even extremely long-lasting migraine aura is not associated with cerebral ischaemia. Therefore, it supports the revised International Headache Society criteria where the term ‘persistent’ aura is proposed.

Endovascular stroke therapy in Austria: a nationwide 1-year experience

BACKGROUND AND PURPOSE

Based on a tight network of stroke units (SUs) and interventional centres, endovascular treatment of acute major intracranial vessel occlusion has been widely implemented in Austria. Documentation of all patients in the nationwide SU registry has thereby become mandatory.

METHODS

Demographic, clinical and interventional characteristics of patients who underwent endovascular treatment for acute ischaemic stroke in 11 Austrian interventional centres between 1 October 2013 and 30 September 2014 were analysed.

RESULTS

In total, 301 patients (50.5% women; median age 70.5 years; median National Institutes of Health Stroke Scale score 17) were identified.193 patients (64.1%) additionally received intravenous thrombolysis. The most frequent vessel occlusion sites were the M1 segment of the middle cerebral artery (n = 161, 53.5%), the intracranial internal carotid artery (n = 60, 19.9%) and the basilar artery (n = 40, 13.3%). Stent retrievers were used in 235 patients (78.1%) and adequate reperfusion (modified Thrombolysis in Cerebral Infarction scores 2b and 3, median onset to reperfusion time 254 min) was achieved in 242 patients (81.4%). Symptomatic intracranial haemorrhage occurred in 7%. 43.8% of patients (n = 132) had good functional outcome (modified Rankin Scale score 0-2) and the mortality rate was 20.9% (n = 63) after 3 months. Compared to the anterior circulation, vertebrobasilar stroke patients had higher mortality. Patients with secondary hospital transportation had better outcomes after 3 months than in-house treated patients.

CONCLUSION

Our results document nationwide favourable outcome and safety rates of endovascular stroke treatment comparable to recent randomized trials. The ability to provide such data and the need to further optimize such an approach also underscore the contribution of respective registries.

Multiple calcified brain metastases in a man with invasive ductal breast cancer

We report a case of a 52-year-old Caucasian man with invasive ductal carcinoma of the breast. One year after initial diagnosis, he developed a generalised epileptic seizure and neuroimaging showed multiple, calcified intracerebral lesions. Owing to these atypical cerebral imaging findings, comprehensive serological and cerebrospinal fluid analysis was conducted and a latent toxoplasmosis was suspected. In order to distinguish between metastases and an infectious disease, a cerebral biopsy was performed, which verified brain metastases. The patient received whole-brain radiotherapy. The last cerebral CT scan, 18 months later showed stable disease. Calcification of brain metastases in patients with breast cancer is very rare. Owing to their non-characteristic radiological appearance with a lack of contrast enhancement, diagnosis of metastases can be difficult. Infectious diseases should be considered within the diagnostic work up. Owing to possible pitfalls, we recommend a widespread differential diagnostic work up in similar cases, and even in cases with a confirmed primary tumour.

The Last 10 Days of Patients With Glioblastoma: Assessment of Clinical Signs and Symptoms as well as Treatment

BACKGROUND

High-grade gliomas are the most frequent primary brain tumors. Despite improvement in diagnostics and treatment, survival is still poor and quality-of-life issues are of major importance. Little is known regarding the clinical signs and symptoms of dying patients with glioblastoma.

OBJECTIVE

The aim of this study was to investigate signs and symptoms as well as therapeutic strategies in patients with glioblastoma in the end-of-life phase in order to improve end-of-life care.

METHODS

In this prospective single-center study, clinical data were obtained using a standardized protocol. We descriptively analyzed signs, symptoms, and therapeutic strategies on a daily basis.

RESULTS

A total of 57 patients, who died due to glioblastoma in a hospital setting, were included. The most frequent signs and symptoms in the last 10 days before death were decrease in level of consciousness (95%), fever (88%), dysphagia (65%), seizures (65%), and headache (33%). Concerning medication, 95% received opioids. There was a high need for nonsteroidal anti-inflammatory drugs (77%) and anticonvulsants (75%). Steroids were given to 56%.

CONCLUSION

Due to a decrease in level of consciousness and cognitive impairment, assessment of clinical signs and symptoms such as headache at the end of life is difficult. Based on the signs and symptoms in the last days before death in patients with glioblastoma, supportive drug treatment remains challenging. Our study emphasizes the importance of standardized guidelines for end-of-life care in patients with glioblastoma.

Epilepsy in the end of life phase of brain tumor patients: a systematic review

Epileptic seizures are common in patients with primary or secondary malignant brain tumor. However, current knowledge on the occurrence of seizures during the end of life (EOL) phase of brain tumor patients is limited. Because symptom management with preservation of quality of life is of major importance for patients with a malignant brain tumor, particularly in the EOL, it is necessary to gain a deeper understanding of seizures and their management during this phase. We performed a systematic review of literature related to epilepsy in the EOL phase of brain tumor patients, based on the electronic resources PubMed, Embase, and Cinahl. The search yielded 442 unique records, of which 11 articles were eligible for further analysis after applying predefined inclusion criteria. Seizures occur relatively frequently in the EOL phase, particularly in patients with high-grade glioma. However, seizure management is often hampered by swallowing difficulties and impaired consciousness. Treatment decisions are largely dependent on expert opinion because a standardized approach for treating seizures in the terminal stage of brain tumor patients is still lacking.

Relative survival of patients with non-malignant central nervous system tumours: a descriptive study by the Austrian Brain Tumour Registry

BACKGROUND

Unlike malignant primary central nervous system (CNS) tumours outcome data on non-malignant CNS tumours are scarce. For patients diagnosed from 1996 to 2002 5-year relative survival of only 85.0% has been reported. We investigated this rate in a contemporary patient cohort to update information on survival.

METHODS

We followed a cohort of 3983 cases within the Austrian Brain Tumour Registry. All patients were newly diagnosed from 2005 to 2010 with a histologically confirmed non-malignant CNS tumour. Vital status, cause of death, and population life tables were obtained by 31 December 2011 to calculate relative survival.

RESULTS

Overall 5-year relative survival was 96.1% (95% CI 95.1-97.1%), being significantly lower in tumours of borderline (90.2%, 87.2-92.7%) than benign behaviour (97.4%, 96.3-98.3%). Benign tumour survival ranged from 86.8 for neurofibroma to 99.7% for Schwannoma; for borderline tumours survival rates varied from 83.2 for haemangiopericytoma to 98.4% for myxopapillary ependymoma. Cause of death was directly attributed to the CNS tumour in 39.6%, followed by other cancer (20.4%) and cardiovascular disease (15.8%).

CONCLUSION

The overall excess mortality in patients with non-malignant CNS tumours is 5.5%, indicating a significant improvement in survival over the last decade. Still, the remaining adverse impact on survival underpins the importance of systematic registration of these tumours.

A single-arm phase II Austrian/German multicenter trial on continuous daily sunitinib in primary glioblastoma at first recurrence (SURGE 01-07)

BACKGROUND

Due to the redundancy of molecular pathways simultaneously involved in glioblastoma growth and angiogenesis, therapeutic approaches intervening at multiple levels seem particularly appealing.

METHODS

This prospective, multicenter, single-arm phase II trial was designed to evaluate the antitumor activity of sunitinib, an oral small-molecule inhibitor of several receptor tyrosine kinases, in patients with first recurrence of primary glioblastoma using a continuous once-daily dosing regimen. Patients received a starting dose of sunitinib 37.5 mg, followed by a maintenance dose between 12.5 mg and 50 mg depending on drug tolerability. The primary endpoint was a 6-month progression-free survival (PFS) rate. Secondary endpoints included median PFS, overall survival (OS), safety/toxicity, quality of life, and translational studies on the expression of sunitinib target molecules.

RESULTS

Forty participants were included in this study, and no objective responses were detected. PFS6 was 12.5%, median PFS 2.2 months, and median OS 9.2 months. Five participants (12.5%) showed prolonged stable disease ≥6 months with a median PFS of 16.0 months (range, 6.4-41.4 mo) and a median OS of 46.9 months (range, 21.2-49.2 mo) for this subgroup. c-KIT expression in vascular endothelial cells (n = 14 participants) was associated with improved PFS. The most common toxicities were fatigue/asthenia, mucositis/dermatitis, dysesthesias, gastrointestinal symptoms, cognitive impairment, leukoctopenia, and thrombocytopenia. Two participants (5%) terminated treatment due to toxicity.

CONCLUSION

Continuous daily sunitinib showed minimal antiglioblastoma activity and substantial toxicity when given at higher doses. High endothelial c-KIT expression may define a subgroup of patients who will benefit from sunitinib treatment by achieving prolonged PFS. ClinicalTrials.gov Identifier: NCT00535379.

Prevention of Poststroke Cognitive Decline: ASPIS – a Multicenter, Randomized, Observer-Blind, Parallel Group Clinical Trial to Evaluate Multiple Lifestyle Interventions – Study Design and Baseline Characteristics

Background

Cognitive impairment after stroke is a considerable burden to patients and their caregivers and occurs in one-third of stroke survivors. No strategy to prevent cognitive decline after stroke exists thus far. Established vascular risk factors have been associated with cognitive decline and may be a target for therapeutic interventions in stroke survivors.

Aim

To test whether intensive multifactorial non-pharmacologic interventions based on lifestyle modification can reduce the risk of cognitive decline in patients who recently suffered ischemic stroke.

Methods

A randomized, controlled, multicenter, observer-blind trial was designed. The reference group obtains stroke care according to standard guidelines. The intervention group additionally receives intensive control and motivation for better compliance with prescribed evidence-based medication, regular blood pressure measurements, healthy diet, regular physical activity and cognitive training. Primary outcomes are the rate of cognitive decline at 24 months, assessed by a neuropsychological test battery and the cognitive subscale of the Alzheimer's Disease Assessment Scale.

Results

202 patients (29% women), aged 62 ± 9 years, were recruited during 2010 to 2012. Stroke related impairment at inclusion was low (mean National Institutes of Health Stroke Scale: 1.9±1.8, median modified Rankin Scale: 1 (0-1)). At baseline, groups did not differ significantly in demographic, clinical or lifestyle characteristics.

Conclusion

The recruitment was successful and the groups are balanced regarding potential confounding variables. The study will provide essential data about the feasibility and efficacy of lifestyle intervention after stroke in order to develop a new approach to prevent cognitive decline in patients with mild ischemic stroke.