Preoperative cervical traction with Gardner-Wells tongs: who profits most?

BACKGROUND

Preoperative traction with the Gardner-Wells tongs (PTGWT) is a valuable option for cervical spine injuries with malalignment. The aim of this study was to analyze the factors related to the treatment success of PTGWT.

METHODS

All consecutive cases with PTGWT due to cervical spine injury with malalignment treated between 01/2010 and 09/2020 were included. Patients' records were reviewed for demographic and clinical characteristics. Treatment success was evaluated upon the angle correction in the sagittal plane using the computed tomography scans before and after the treatment.

RESULTS

Of 20 patients in the final analysis (median age: 77.5 years; 12 females [60%]), 14 individuals were treated for the type-II odontoid fracture, and six cases presented with subluxation fractures between C3 and C7. After PTGWT and subsequent intraoperative reposition, there was an improvement of the median deviation angle from initial 32° to 5.5°. PTGWT resulted in a significant improvement of the median deviation angle for the odontoid (17°, P<0.0001), but not for the subluxation (4°, P=0.10) fractures. The time interval between trauma and PTGWT was associated with the treatment success of subluxation (P=0.051) but not of odontoid (P=0.87) fractures. Older individuals aged ≥51 years showed better reposition results with PTGWT (17° vs. 7.5°, P=0.02). There were no PTGWT-related complications in the cohort.

CONCLUSIONS

PTGWT is an effective and safe treatment for cervical spine injuries with malalignment. The patients with odontoid fractures might particularly profit from the PTGWT. Treatment delay seems more relevant for PTGWT success in subluxation than in odontoid fractures.

Long-term outcome after management of pilocytic astrocytoma in the posterior fossa in a pediatric population

Background and purpose

To assess the impact of posterior fossa pilocytic astrocytoma (PA) removal in pediatric patients, with special focus on postoperative neurological outcome after repeated surgery for tumor remnants.

Methods

Our institutional database was screened for patients with PA treated between 2000 and 2019. Patients ≤ 18 years of age with complete clinical records, preoperative contrast enhanced magnetic resonance imaging (MRI) and postoperative follow-up time of ≥ 6 months were suitable for study inclusion. Functional outcome was quantified with the modified Ranking Scale (mRS) score and assessed at admission, at discharge and at every follow-up investigation. Predictors of hydrocephalus, cranial nerve deficits and tumor recurrence were evaluated.

Results

A total of 57 pediatric patients with a mean age of 7.7 ± 4.8 years were included in the analysis. 27 (47.3%) children suffered from hydrocephalus at diagnosis, out of which 19 (33.3%) required a subsequent VP-Shunt. 22 (39.3%) patients had a partial resection, of which 9 (40.9%) went through second-look surgery. 2 patients with initially radiological confirmation of complete resection, had a tumor recurrence at FU and needed second-look surgery. Among the children requiring second-look surgery, 7 (63.6%) had a complete resection. Favorable outcome (mRS≤2) after initial and second-look surgery was observed in 52 patients (91.2%). Univariate analysis identified tumor location in the floor of the 4th ventricle (p = 0.030), and repeated surgery for tumor remnant removal (p = 0.043) as predictors for post-operative cranial nerve deficits. Multivariate analysis confirmed this independent association. The incidence of tumor recurrence occurred more often in patients with previous partial resection (p = 0.009) as well as in lesions located in the cerebellar peduncles (p = 0.043). Partial resection remained an independent predictor after multivariate logistic regression analysis (p = 0.045).

Conclusions

Incomplete resection of posterior fossa PA is a risk factor for tumor recurrence and repeated surgery to remove tumor remnants increases the risk of new postoperative deficits. Thus, the risk of iatrogenic deterioration due to second look surgery should be implemented in the primary pre- and intraoperative decision-making.

CTNI-29. INVESTIGATING SAFETY AND EFFICACY OF TTFIELDS PRIOR AND CONCOMITANT TO RADIOTHERAPY IN NEWLY DIAGNOSED GLIOBLASTOMA - FIRST RESULTS OF THE PRICOTTF PHASE I/II TRIAL

Background

A synergistic inhibiting effect on glioblastoma cell proliferation was reported for the combination of TTFields and radiotherapy. Based on these preclinical findings, we performed the phase I/II PriCoTTF trial in adult nGBM patients to investigate the safety and efficacy of TTFields therapy initiated prior and concomitant to radiochemotherapy.

MATERIAL AND METHODS

In this phase I/II trial, TTFields therapy was initiated following surgery and continued throughout radiochemotherapy and adjuvant chemotherapy for a total of approximately 9 months. TTFields rechallenge was allowed at recurrence. Radiotherapy was conducted with arrays applied on the patients’ scalp. Safety and tolerance are the study’s primary endpoint, determined by a selection of pre-specified treatment-limiting toxicities (TLTs).

RESULTS

A total of 33 patients have been enrolled. Patients' characteristics were mostly typical for glioblastoma, except for a rather low fraction of patients with gross total resection (GTR, 22.5%). The distribution of adverse events of ≥ common toxicity criteria (CTC) grade 3 was comparable to that of established glioblastoma trials. Notably, skin toxicity of ≥ CTC grade 3 was uncommon (n = 2, 6%). No patient developed TLTs. Median TTFields treatment duration was 8.4 months. Overall survival data was not mature enough (event rate 48%) to allow for a definite conclusion

Notably, on multivariable Cox regression, the number of days with TTFields adherence &gt; 23 hours was independently associated with overall survival (HR 0.96, 95% confidence interval 0.93 - 0.99, p = 0.008).

CONCLUSION

The PriCoTTF trial met its primary endpoint indicating that combined TTFields and radiotherapy is safe and well tolerated. High-grade skin toxicity was quite uncommon and the patients with high TTFields adherence seem to perform particularly well. An extended follow-up is required to provide first estimates regarding putative efficacy. At that point in time, the reduced overall TTFields duration and fraction of patients with GTR need to be factored in.

CTNI-34. PRECISION NEURO-ONCOLOGY - A PILOT ANALYSIS OF PERSONALIZED TREATMENT IN RECURRENT GLIOMA

PURPOSE

When brain cancer relapses, treatment options are scarce. The use of molecularly matched targeted therapies may provide a feasible and efficacious way to treat individual patients based on the molecular tumor profile. Since little information is available on this strategy in neuro-oncology, we retrospectively analyzed the clinical course of 41 patients who underwent advanced molecular testing at disease relapse.

METHODS

We performed Sanger sequencing, targeted next generation sequencing, and immunohistochemistry for analysis of potential targets, including programmed death ligand 1, cyclin D1, phosphorylated mechanistic Target of Rapamycin, telomerase reverse transcriptase promoter mutation, cyclin-dependent kinase inhibitor 2A/B deletion, or BRAF-V600E mutation. In selected patients, whole exome sequencing was conducted.

RESULTS

The investigation included 41 patients of which 32 had isocitrate dehydrogenase (IDH) wildtype glioblastoma. Molecular analysis revealed actionable targets in 31 of 41 tested patients and 18 patients were treated accordingly (matched therapy group). Twenty-three patients received molecularly unmatched empiric treatment (unmatched therapy group). In both groups, 16 patients were diagnosed with recurrent IDH wildtype glioblastoma. The number of severe adverse events was comparable between the therapy groups. Regarding the IDH wildtype glioblastoma patients, median progression-free survival (mPFS) and median overall survival (mOS) were longer in the matched therapy group (mPFS: 3.8 versus 2.0 months, p = 0.0057; mOS: 13.0 versus 4.3 months, p = 0.0357).

CONCLUSIONS

These encouraging data provide a rationale for molecularly matched targeted therapy in glioma patients. For further validation, future study designs need to additionally consider prevalence and persistence of actionable molecular alterations in patient tissue.

CT and DSA for evaluation of spontaneous intracerebral lobar bleedings

Purpose

This study retrospectively examined the extent to which computed tomography angiography (CTA) and digital subtraction angiography (DSA) can help identify the cause of lobar intracerebral bleeding.

Materials and methods

In the period from 2002 to 2020, data from patients who were >18 years at a university and an academic teaching hospital with lobar intracerebral bleeding were evaluated retrospectively. The CTA DSA data were reviewed separately by two neuroradiologists, and differences in opinion were resolved by consensus after discussion. A positive finding was defined as an underlying vascular etiology of lobar bleeding.

Results

The data of 412 patients were retrospectively investigated. DSA detected a macrovascular cause of bleeding in 125/412 patients (33%). In total, sixty patients had AVMs (15%), 30 patients with aneurysms (7%), 12 patients with vasculitis (3%), and 23 patients with dural fistulas (6%). The sensitivity, specificity, positive and negative predictive values, and accuracy of CTA compared with DSA were 93, 97, 100, and 97%. There were false-negative CTA readings for two AVMs and one dural fistula.

Conclusion

The DSA is still the gold standard diagnostic modality for detecting macrovascular causes of ICH; however, most patients with lobar ICH can be investigated first with CTA, and the cause of bleeding can be found. Our results showed higher sensitivity and specificity than those of other CTA studies.

OS06.5.A Investigating safety and efficacy of TTFields prior and concomitant to radiotherapy in newly diagnosed glioblastoma - the PriCoTTF phase I/II trial

Background

The EF-14 phase III trial demonstrated improved survival for patients with newly diagnosed glioblastoma (nGBM) when TTFields therapy was added to adjuvant temozolomide chemotherapy. TTFields at 200 kHz are applied to the tumor utilizing arrays on the patients’ scalp. In preclinical studies, a synergistic inhibiting effect on glioblastoma cell proliferation was found for the combination of TTFields and radiotherapy. Based on these findings, we conduct the phase I/II PriCoTTF trial in adult nGBM patients to investigate the safety and efficacy of TTFields therapy initiated prior and concomitant to radiochemotherapy.

Material and Methods

Per study protocol, TTFields therapy is initiated following surgery and completed wound healing. Continuing throughout radiochemotherapy and adjuvant chemotherapy, TTFields therapy is used for approximately 9 months in total with TTFields rechallenge allowed at recurrence. Radiotherapy is conducted with arrays applied on the patients’ scalp. A total recruitment of 33 patients was sought, with 20 patients in arm A receiving normo-fractionated radiotherapy, and 13 elderly patients in arm B receiving hypo-fractionated radiotherapy. Safety and tolerance are the study’s primary endpoint, analyzed by a selection of pre-specified treatment-limiting toxicities (TLTs).

Results

A total of 33 patients have been enrolled. Patients' characteristics were mostly typical for glioblastoma, except for a rather low fraction of patients with gross total resection (GTR, 22.5%). The distribution of adverse events of common toxicity criteria (CTC) grade 3 or higher was comparable to that of established glioblastoma trials. Notably, skin toxicity of CTC grade 3 or higher was quite uncommon (n=2, 6%). As no patient developed TLTs, the study's primary endpoint was met. Median TTFields treatment duration was 8.4 months. Overall survival data was not mature enough (event rate 48%) to allow for a definite conclusion. Notably, on multivariable Cox regression, the number of days with TTFields adherence of more than 23 hours was independently associated with overall survival (HR 0.96, 95% confidence interval 0.93 - 0.99, p=0.008).

Conclusion

The PriCoTTF trial met its primary endpoint indicating that combined TTFields and radiotherapy is safe and well tolerated. High-grade skin toxicity was quite uncommon and the patients with high TTFields adherence seem to perform particularly well. An extended follow-up is required to provide first estimates regarding putative efficacy. At that point in time, the reduced overall TTFields duration and fraction of patients with GTR need to be factored in.

Time interval between the diagnosis of breast cancer and brain metastases impacts prognosis after metastasis surgery

Purpose

Breast cancer (BC) is the most frequently diagnosed tumor entity in women. Occurring at different time intervals (TI) after BC diagnosis, brain metastases (BM) are associated with poor prognosis. We aimed to identify the risk factors related to and the clinical impact of timing on overall survival (OS) after BM surgery.

Methods

We included 93 female patients who underwent BC BM surgery in our institution (2008–2019). Various clinical, radiographic, and histopathologic markers were analyzed with respect to TI and OS.

Results

The median TI was 45.0 months (range: 9–334.0 months). Fifteen individuals (16.1%) showed late occurrence of BM (TI ≥ 10 years), which was independently related to invasive lobular BC [adjusted odds ratio (aOR) 9.49, 95% confidence interval (CI) 1.47–61.39, p = 0.018] and adjuvant breast radiation (aOR 0.12, 95% CI 0.02–0.67, p = 0.016). Shorter TI (< 5 years, aOR 4.28, 95% CI 1.46–12.53, p = 0.008) was independently associated with postoperative survival and independently associated with the Union for International Cancer Control stage (UICC) III–IV of BC (aOR 4.82, 95% CI 1.10–21.17, p = 0.037), midline brain shift in preoperative imaging (aOR10.35, 95% CI 1.09–98.33, p = 0.042) and identic estrogen receptor status in BM (aOR 4.56, 95% CI 1.35–15.40, p = 0.015).

Conclusions

Several factors seem to influence the period between BC and BM. Occurrence of BM within five years is independently associated with poorer prognosis after BM surgery. Patients with invasive lobular BC and without adjuvant breast radiation are more likely to develop BM after a long progression-free survival necessitating more prolonged cancer aftercare of these individuals.

Prediction of Short and Long Survival after Surgery for Breast Cancer Brain Metastases

Background: Brain metastases requiring surgical treatment determine the prognosis of patients with breast cancer. We aimed to develop the scores for the prediction of short (<6 months) and long (≥3 years) survival after BCBM surgery. Methods: Female patients with BCBM surgery between 2008 and 2019 were included. The new scores were constructed upon independent predictors for short and long postoperative survival. Results: In the final cohort (n = 95), 18 (18.9%) and 22 (23.2%) patients experienced short and long postoperative survival, respectively. Breast-preserving surgery, presence of multiple brain metastases and age ≥ 65 years at breast cancer diagnosis were identified as independent predictors of short postoperative survival. In turn, positive HER2 receptor status in brain metastases, time interval ≥ 3 years between breast cancer and brain metastases diagnosis and KPS ≥ 90% independently predicted long survival. The appropriate short and long survival scores showed higher diagnostic accuracy for the prediction of short (AUC = 0.773) and long (AUC = 0.775) survival than the breast Graded Prognostic Assessment score (AUC = 0.498/0.615). A cumulative survival score (total score) showed significant association with overall survival (p = 0.001). Conclusion: We identified predictors independently impacting the prognosis after BCBM surgery. After external validation, the presented scores might become useful tools for the selection of proper candidates for BCBM surgery.

A New Subform? Fast-Progressing, Severe Neurological Deterioration Caused by Spinal Epidural Lipomatosis

Spinal epidural lipomatosis (SEL) is a rare condition caused by hypertrophic growth of epidural fat. The prevalence of SEL in the Western world is approximately 1 in 40 patients and is likely to increase due to current medical and socio-economic developments. Rarely, SEL can lead to rapid severe neurological deterioration. The pathophysiology, optimal treatment, and outcome of these patients remain unclear. This study aims to widen current knowledge about this “SEL subform” and to improve its clinical management. A systematic literature review according to the PRISMA guidelines using PubMed, Scopus, Web of Science, and Cochrane Library was used to identify publications before 7 November 2021 reporting on acute/rapidly progressing, severe SEL. The final analysis comprised 12 patients with acute, severe SEL. The majority of the patients were male (9/12) and multimorbid (10/12). SEL mainly affected the thoracic part of the spinal cord (11/12), extending a median number of 7 spinal levels (range: 4–19). Surgery was the only chosen therapy (11/12), except for one critically ill patient. Regarding the outcome, half of the patients regained independence (6/11; = modified McCormick Scale ≤ II). Acute, severe SEL is a rare condition, mainly affecting multimorbid patients. The prognosis is poor in nearly 50% of the patients, even with maximum therapy. Further research is needed to stratify patients for conservative or surgical treatment.

Fully Automated MR Based Virtual Biopsy of Cerebral Gliomas

OBJECTIVE

The aim of this study was to investigate the diagnostic accuracy of a radiomics analysis based on a fully automated segmentation and a simplified and robust MR imaging protocol to provide a comprehensive analysis of the genetic profile and grading of cerebral gliomas for everyday clinical use.

METHODS

MRI examinations of 217 therapy-naïve patients with cerebral gliomas, each comprising a non-contrast T1-weighted, FLAIR and contrast-enhanced T1-weighted sequence, were included in the study. In addition, clinical and laboratory parameters were incorporated into the analysis. The BraTS 2019 pretrained DeepMedic network was used for automated segmentation. The segmentations generated by DeepMedic were evaluated with 200 manual segmentations with a DICE score of 0.8082 ± 0.1321. Subsequently, the radiomics signatures were utilized to predict the genetic profile of ATRX, IDH1/2, MGMT and 1p19q co-deletion, as well as differentiating low-grade glioma from high-grade glioma.

RESULTS

The network provided an AUC (validation/test) for the differentiation between low-grade gliomas vs. high-grade gliomas of 0.981 ± 0.015/0.885 ± 0.02. The best results were achieved for the prediction of the ATRX expression loss with AUCs of 0.979 ± 0.028/0.923 ± 0.045, followed by 0.929 ± 0.042/0.861 ± 0.023 for the prediction of IDH1/2. The prediction of 1p19q and MGMT achieved moderate results, with AUCs of 0.999 ± 0.005/0.711 ± 0.128 for 1p19q and 0.854 ± 0.046/0.742 ± 0.050 for MGMT.

CONCLUSION

This fully automated approach utilizing simplified MR protocols to predict the genetic profile and grading of cerebral gliomas provides an easy and efficient method for non-invasive tumor decoding.

Role of Brain Natriuretic Peptide in the Prediction of Early Postoperative Seizures Following Surgery for Traumatic Acute Subdural Hematoma: A Prospective Study

INTRODUCTION

Brain natriuretic peptide (BNP) is a reliable biomarker in the acute phase of traumatic brain injury. However, the relationship between BNP and traumatic acute subdural hematoma (aSDH) has not yet been addressed. This study aimed to analyze BNP levels on admission in surgically treated patients and assess their relationship with early postoperative seizures (EPS) and functional outcomes.

METHODS

Patients with unilateral traumatic aSDH who were surgically treated in our department between July 2017 and May 2020 were included in the study. BNP was preoperatively measured. Patients' neurologic condition, radiographic variables on initial cranial computed tomography, sodium serum levels on admission, and occurrence of EPS were prospectively assessed. Functional outcome was assessed using the modified Rankin Scale (mRS) at discharge and follow-up (at 2-3 months). A poor outcome was defined by a mRS score > 3.

RESULTS

EPS occurred in 20 (19.6%) of 102 surgically treated patients in the final cohort on the median day 3. A significant association between EPS and a poor Glasgow Coma Scale score at the 7th postoperative day was found, which in turn independently predicted a poor functional outcome at discharge and follow-up. Nonetheless, EPS were not associated with poor functional outcomes. The multivariate analysis revealed BNP > 95.4 pg/ml (aOR = 5.7, p = 0.003), sodium < 137.5 mmol/l (aOR = 4.6, p = 0.009), and left-sided aSDH (aOR = 4.4, p = 0.020) as independent predictors of EPS.

CONCLUSION

In the early postoperative phase of traumatic aSDH, EPS were associated with worse neurologic conditions, which in turn independently predicted poor outcomes at discharge and follow-up. Although several EPS risk factors have already been elucidated, this study presents BNP as a novel reliable predictor of EPS. Further larger studies are needed to determine whether a more precise estimate of EPS risk using BNP levels can be reached.

Analysis of Brain Natriuretic Peptide Levels after Traumatic Acute Subdural Hematoma and the Risk of Post-Operative Cerebral Infarction

Traumatic acute subdural hematoma (aSDH) is associated with a high mortality rate caused by post-operative cerebral infarction. Recently, brain natriuretic peptide (BNP) was considered a reliable biomarker in the acute phase of traumatic brain injuries. We therefore aimed in this study to analyze BNP levels on admission, identify the predictors of their elevation, and assess the relationship between BNP and the risk of post-operative cerebral infarction. Patients with isolated, unilateral, traumatic aSDH who were admitted to our department between July 2017 and May 2020 were enrolled in this study. On admission, cranial computer tomography (CCT) and BNP sampling were simultaneously performed. Additionally, the time between head trauma and BNP sampling (TTS) was assessed. Admission radiographic variables included hematoma volumes, midline shift, and degree of brain edema. Cerebral infarction was detected on postoperative CCT. In total, 130 patients were included in this study. Surgical treatment was performed in 82.3% (n = 107) of cases. The multiple regression analysis showed that larger hematoma volumes (p = 0.032) and advanced age (p = 0.005) were independent predictors of elevated BNP when TTS <24 h. The binomial logistical regression analysis identified BNP with a cutoff value of <29.4 pg/mL (TTS = 3-12 h, adjusted odds ratio [aOR] = 16.5, p = 0.023) as an independent predictor of post-operative cerebral infarction. Elevated BNP levels in the first 24 h post-trauma were related to larger hematoma volumes and advanced age. Further, an increased risk of post-operative cerebral infarction was identified in patients with lower BNP levels in the post-traumatic period 3-12 h.

CTNI-38. PriCoTTF TRIAL: A PHASE I/II TRIAL OF TTFIELDS PRIOR AND CONCOMITANT TO RADIOTHERAPY IN NEWLY DIAGNOSED GLIOBLASTOMA

TTFields therapy is applied at 200 kHz by arrays that are placed at the patients’ scalp. In the phase 3 EF-14 trial, survival rates were significantly improved when adding tumor-treating fields (TTFields) to adjuvant temozolomide-based chemotherapy in patients with newly diagnosed glioblastoma (nGBM). Preclinical studies showed that combination of TTFields and radiotherapy synergistically impaired glioblastoma cell growth. Here, we present the PriCoTTF trial, which is enrolling nGBM patients and will assess the safety and efficacy of TTFields initiated prior and concomitant to radiochemotherapy. Following surgery and wound-healing, TTFields therapy is initiated in adult nGBM patients. TTFields therapy continues throughout radiochemotherapy and adjuvant chemotherapy for a total of approximately 9 months. During radiotherapy, the arrays - through which TTFields is delivered - remain on the patients’ scalp. Totally, thirty-three patients are planned to be enrolled in two treatment arms. In arm A, 20 patients receive normo-fractionated radiotherapy, whereas in the elderly arm, arm B, 13 patients receive hypo-fractionated radiotherapy. The primary endpoint of this trial is safety and tolerance that will be gauged by a set of pre-specified treatment-limiting toxicities. Secondary endpoints include the frequency of adverse events, progression-free survival (PFS), and overall survival (OS). The trial is currently enrolling patients at four sites in Germany. At the time of abstract submission, 9 patients enrolled in Arm B. Patient recruitment for arm A has been completed with. We will present initial practical experiences as well as preliminary safety and tolerance data. There is a biological rationale for combining TTFields and radiotherapy to further improve survival of GBM patients. In the presented phase I/II trial, the safety and efficacy of TTFields initiated prior and concomitant to RT in nGBM will be assessed. In addition, initial efficacy data (phase II) may serve as a rationale for a putative randomized phase III trial.

Electrolyte and renal disorders in patients with newly diagnosed glioblastoma

Purpose: Disturbances of electrolytes and renal function have been linked to the prognosis of critically ill patients and recently also of cancer patients. This study aimed to assess electrolyte and renal disorders in glioblastoma patients and evaluate their prognostic effect. Methods: Medical records of patients with newly diagnosed glioblastoma between 2005 and 2018 were retrospectively reviewed for electrolyte and renal function parameters and for demographic, clinical and outcome parameters. Results: Electrolyte and renal function disorders were associated with poorer survival in univariate and Kaplan-Meier analysis. Multivariate analysis revealed hypochloremia as an independent prognostic factor for overall and 1-year survival. Conclusion: Only hypochloremia showed an association with glioblastoma prognosis, independent of other known prognostic factors, as age or molecular status.

PaCO2-management in the neuro-critical care of patients with subarachnoid hemorrhage

The partial pressure of carbon dioxide (PaCO2) in the arterial blood is a strong vasomodulator affecting cerebral blood flow and the risk of cerebral edema and ischemia after acute brain injury. In turn, both complications are related to poor outcome in patients with aneurysmal subarachnoid hemorrhage (aSAH). We aimed to analyze the effect of PaCO2 levels on the course and outcome of aSAH. All patients of a single institution treated for aSAH over 13.5 years were included (n = 633). Daily PaCO2 values from arterial blood gas measurements were recorded for up to 2 weeks after ictus. The study endpoints were: delayed cerebral ischemia (DCI), need for decompressive craniectomy due to increased intracranial pressure > 20 mmHg refractory to conservative treatment and poor outcome at 6-months follow-up (modified Rankin scale > 2). By correlations with the study endpoints, clinically relevant cutoffs for the 14-days mean values for the lowest and highest daily PaCO2 levels were defined by receiver operating characteristic curve analysis. Association with the study endpoints for the identifies subgroups was analyzed using multivariate analysis. The optimal range for PaCO2 values was identified between 30 and 38 mmHg. ASAH patients with poor initial condition (WFNS 4/5) were less likely to show PaCO2 values within the range of 30-38 mmHg (p < 0.001, OR = 0.44). In the multivariate analysis, PaCO2 values between 30 and 38 mmHg were associated with a lower risk for decompressive craniectomy (p = 0.042, aOR = 0.27), DCI occurrence (p = 0.035; aOR = 0.50), and poor patient outcome (p = 0.004; aOR = 0.42). The data from this study shows an independent positive association between low normal mean PaCO2 values during the acute phase of aSAH and patients' outcome. This effect might be attributed to the reduction of intracranial hypertension and alterations in the cerebral blood flow.

P14.64 PriCoTTF Trial: A phase I/II trial of TTFields prior and concomitant to radiotherapy in newly diagnosed glioblastoma

BACKGROUND

TTFields therapy is applied at 200 kHz by arrays that are placed at the patients’ scalp. In the phase 3 EF-14 trial, survival rates were significantly improved when adding tumor-treating fields (TTFields) to adjuvant temozolomide-based chemotherapy in patients with newly diagnosed glioblastoma (nGBM). In preclinical studies, the combination of TTFields and radiotherapy synergistically impaired proliferation and growth of glioblastoma cells. Here, we present the PriCoTTF trial, which is enrolling nGBM patients and will assess the safety and efficacy of TTFields initiated prior and concomitant to radiochemotherapy.

MATERIAL AND METHODS

Following surgery and complete wound-healing, TTFields therapy is initiated in adult nGBM patients. TTFields therapy continues throughout radiochemotherapy and adjuvant chemotherapy for a total of approximately 9 months. During radiotherapy, the arrays - through which TTFields is delivered - remain on the patients’ scalp. Totally, thirty-three patients are planned to be enrolled in two treatment arms. In arm A, 20 patients receive normo-fractionated radiotherapy, whereas in the elderly arm, arm B, 13 patients receive hypo-fractionated radiotherapy. Concomitant and adjuvant chemotherapy follow institutional standards and interdisciplinary tumor conference recommendations.

RESULTS

The primary endpoint of this trial is safety and tolerance that will be gauged by a set of pre-specified treatment-limiting toxicities. Secondary endpoints include the frequency of adverse events, progression-free survival (PFS), and overall survival (OS). The trial is currently enrolling patients at four sites in Germany. At the time of abstract submission, 9 patients enrolled in Arm B. Patient recruitment for arm A has been completed with 20 patients enrolled. We will present initial practical experiences as well as preliminary safety and tolerance data.

CONCLUSION

There is a biological rationale for combining TTFields and radiotherapy to further improve survival of GBM patients. In the presented phase I/II trial, the safety and efficacy of TTFields initiated prior and concomitant to RT in nGBM will be assessed. In addition, initial efficacy data (phase II) may serve as a rationale for a putative randomized phase III trial.

HER2 Receptor Conversion Is a strong Survival Predictor in Patients with Breast Cancer Brain Metastases

BACKGROUND

Hormone and human epidermal growth factor receptor 2 (HER2/neu) receptor status is prognostic and predictive in breast cancer (BC) and guides the choice of therapy. However, owing to receptor conversion, the receptor status can differ in metastases compared with that of the primary tumor. The aim of the present study was to analyze the prognostic value of receptor status, receptor conversion, and clinical parameters in patients with resected BC brain metastases (BMs).

METHODS

Patients with BCBMs treated at our institution from July 2007 to December 2019 were eligible for the present study. The receptor status of the BC and corresponding BMs and the occurrence of receptor conversion were separately recorded for 3 common receptors: HER2/neu, estrogen receptor, and progesterone receptor. The association between the receptor status or receptor conversion and clinical parameters was adjusted for outcome-relevant patient and tumor characteristics.

RESULTS

The final analysis included 78 patients. HER2/neu receptor status in BMs was associated with overall survival (P = 0.033). Receptor conversion was identified in 39 patients (50.0%): HER2/neu, n = 9 (11.5%); estrogen receptor, n = 22 (28.2%); and progesterone receptor, n = 25 (32.1%). In the final multivariate Cox regression analysis, HER2/neu receptor conversion (adjusted hazard ratio [aHR], 3.58; P = 0.006), Karnofsky performance status score <70% (aHR, 3.11; P = 0.048), infratentorial BM location (aHR, 2.49; P = 0.007), and age ≥55 years at BM diagnosis (aHR, 2.20; P = 0.046) were independently associated with poorer survival.

CONCLUSIONS

Of the 3 common BC receptors, only HER2/neu receptor conversion was strongly associated with the prognosis of patients with surgically treated BCBMs. The clinical relevance of the reevaluation of receptor status in BMs favors surgical treatment of patients with noneloquent BCBMs.

The Subarachnoid Hemorrhage-Weather Myth: A Long-Term Big Data and Deep Learning Analysis

Objective: The frequency of aneurysmal subarachnoid hemorrhage (aSAH) presents complex fluctuations that have been attributed to weather and climate changes in the past. In the present long-term big data and deep learning analysis, we have addressed this long-held myth.

Methods: Bleeding dates and basic demographic data for all consecutive patients (n = 1,271) admitted to our vascular center for treatment of aSAH between January 2003 and May 2020 (6,334 days) were collected from our continuously maintained database. The meteorological data of the local weather station, including 13 different weather and climate parameters, were retrieved from Germany's National Meteorological Service for the same period. Six different deep learning models were programmed using the Keras framework and were trained for aSAH event prediction with meteorological data from January 2003 to June 2017, with 10% of this dataset applied for data validation and model improvement. The dataset from July 2017 to May 2020 was tested for aSAH event prediction accuracy for all six models using the area under the receiver operating characteristic curve (AUROC) as the metric.

Results: The study group comprised of 422 (33.2%) male and 849 (66.8%) female patients with an average age of 55 ± 14 years. None of the models showed an AUROC larger than 60.2. From the presented data, the influence of weather and climate on the occurrence of aSAH events is extremely unlikely.

Conclusion: The myth of special weather conditions influencing the frequency of aSAH is disenchanted by this long-term big data and deep learning analysis.

Size does matter: The role of decompressive craniectomy extent for outcome after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

In previous studies in patients with traumatic brain injury and ischemic stroke, the size of decompressive craniectomy (DC) was reported to be paramount with regard to patient outcomes. We aimed to identify the impact of DC size on treatment results in individuals with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

The extent of DC in 232 patients with SAH who underwent bifrontal or hemicraniectomy between January 2003 and December 2015 was analyzed using semi-automated surface measurements. The study endpoints were course of intracranial pressure (ICP) treatment after DC, occurrence of cerebral infarcts, in-hospital mortality, and unfavorable outcome at 6 months (defined as modified Rankin scale score >3). The associations of DC size with the study endpoints were adjusted for DC timing, patient age, clinical and radiographic severity of SAH, aneurysm location, and treatment modality.

RESULTS

The mean DC surface area was 100.9 (±45.8) cm² . In multivariate analysis, a large DC (>105 cm² ) was independently associated with a lower risk of cerebral infarcts (adjusted odds ratio [aOR] 0.30, 95% confidence interval [CI] 0.16-0.56), in-hospital mortality (aOR 0.28, 95% CI 0.14-0.56) and unfavorable outcome (aOR 0.51, 95% CI 0.27-0.98). Moreover, SAH patients with a small DC size (<75 cm² ) were more likely to require prolonged (>3 days, aOR 3.60, 95% CI 1.37-9.42) and enhanced (aOR 2.31, 95% CI 1.12-4.74) postoperative ICP treatment.

CONCLUSION

This is the first study showing the impact of DC size on postoperative ICP control and patient outcome in the context of SAH; specifically, a large craniectomy flap (>105 cm² ) might lead to better outcomes in SAH patients requiring decompressive surgery.

Case Report: Pseudomeningeosis and Demyelinating Metastasis-Like Lesions From Checkpoint Inhibitor Therapy in Malignant Melanoma

Immune checkpoint inhibitors (ICIs) have considerably expanded the effective treatment options for malignant melanoma. ICIs revert tumor-associated immunosuppression and potentiate T-cell mediated tumor clearance. Immune-related neurologic adverse events (irNAEs) manifest in the central (CNS) or peripheral nervous system (PNS) and most frequently present as encephalitis or myasthenia gravis respectively. We report on a 47-year old male patient with metastatic melanoma who developed signs of cerebellar disease five weeks after the start of ICI treatment (ipilimumab and nivolumab). Magnetic resonance imaging (MRI) of the brain and spine revealed multiple new contrast enhancements suggestive of parenchymal and leptomeningeal metastasis. Cerebral spinal fluid (CSF) evaluation showed a lymphomononuclear pleocytosis in the absence of tumor cells. Subsequent stereotactic brain biopsy confirmed demyelinating disease. High-dose corticosteroid treatment resulted in immediate improvement of the clinical symptoms. MRI scans and CSF re-evaluation were conducted six weeks later and showed a near-complete remission. The strong resemblance to neoplastic CNS dissemination and irNAEs is a particularly difficult diagnostic challenge. Treating physicians should be aware of irNAEs as those can be effectively treated with high-dose steroids.

Lipomas as an Extremely Rare Cause for Brachial Plexus Compression: A Case Series and Systematic Review

Introduction  Brachial plexus lipomas are extremely rare benign tumors that may cause slow progression of neurological deficits leading to thoracic outlet syndrome. Up to now, surgery remains challenging. The aim of this study is to present our surgical treatment regime and long-term neurological outcome in three cases of giant brachial plexus lipomas and to show results of systematic review.

Patients and Methods  Retrospective analysis of our database “peripheral nerve lesion” to identify patients suffering from brachial plexus lipomas between January 1, 2012, and December 31, 2019. Systematic review was performed for literature published until March 31, 2020, analyzing PubMed, Google Scholar, Scopus, and the Cochrane Collaboration Library independently by two authors.

Results  Over the past years, three patients suffering from giant brachial plexus lipomas attended to our neurosurgical department. All patients underwent preoperative magnetic resonance imaging (MRI), ultrasound examinations, and electrophysiological testing. Tumors were removed microsurgically via anterior/posterior, supraclavicular/infraclavicular, and combined approaches. The patients were accessed postoperatively by MRI and clinical follow-up. Systematic review of the literature revealed 22 cases, which were analyzed in regard to demographics, surgical treatment, and neurological outcome.

Conclusion  Brachial plexus lipomas are an extremely rare cause for brachial plexus compression. Total microsurgical removal with intraoperative electrophysiological monitoring is the treatment of choice with excellent long-term MRI and clinical outcome.

The 2016 Edition of the WHO Classification of Primary Brain Tumors: Applicable to Assess Individual Risk of Recurrence in Atypical Meningioma? A Single-Center Experience

BACKGROUND AND STUDY AIMS/OBJECT

 Despite the relevance of molecular criteria for brain tumor diagnosis and prognosis, meningioma grading is still solely based on histologic features. Atypical meningiomas (AMs; WHO grade II) display a great histologic heterogeneity and individual courses of disease can differ significantly. This study aimed to identify clinically aggressive AMs that are prone to early recurrence after gross total resection (GTR) by assessing a specific histologic score.

PATIENTS AND METHODS

 A retrospective analysis of 28 consecutive patients (17 females and 11 males; mean age of 62 years [range: 35-88 years]) treated in our institution between January 2006 and December 2015 was performed. Basic demographic and clinical characteristics were assessed. A scoring scale was designed to address the histologic diversity by summing up the individual histologic features in every tumor sample. According to that, points were awarded as follows: major AM defining criterion (3 points) and minor criterion (1 point).

RESULTS

 The subclassification based on our specific histologic score revealed no significant difference in frequency of one (46.4%) or two (42.9%) AM defining features; three criteria were less frequently seen (10.7%). Mean follow-up was 61.89 ± 9.03 months. Local recurrence occurred in 35.7% after a mean time of 37.4 ± 22.6 months after primary surgery. Age > 60 years was significantly associated with a shorter progression-free survival (PFS). There was a trend toward shorter PFS with increasing scores, tantamount with the presence of several AM defining histologic criteria in one sample. No tumor relapse was seen when diagnosis was based only on minor criteria.

CONCLUSION

 AMs display a histologic diversity. There is a trend toward shorter PFS with increasing numbers of AM defining histologic features. The inclusion of this score in the decision algorithm regarding further treatment for patients >60 years after GTR might be helpful and should be evaluated in further studies.

Machine learning-based differentiation between multiple sclerosis and glioma WHO II°-IV° using O-(2-[18F] fluoroethyl)-L-tyrosine positron emission tomography

INTRODUCTION

This study aimed to test the diagnostic significance of FET-PET imaging combined with machine learning for the differentiation between multiple sclerosis (MS) and glioma II°-IV°.

METHODS

Our database was screened for patients in whom FET-PET imaging was performed for the diagnostic workup of newly diagnosed lesions evident on MRI and suggestive of glioma. Among those, we identified patients with histologically confirmed glioma II°-IV°, and those who later turned out to have MS. For each group, tumor-to-brain ratio (TBR) derived features of FET were determined. A support vector machine (SVM) based machine learning algorithm was constructed to enhance classification ability, and Receiver Operating Characteristic (ROC) analysis with area under the curve (AUC) metric served to ascertain model performance.

RESULTS

A total of 41 patients met selection criteria, including seven patients with MS and 34 patients with glioma. TBR values were significantly higher in the glioma group (TBRmax glioma vs. MS: p = 0.002; TBRmean glioma vs. MS: p = 0.014). In a subgroup analysis, TBR values significantly differentiated between MS and glioblastoma (TBRmax glioblastoma vs. MS: p = 0.0003, TBRmean glioblastoma vs. MS: p = 0.0003) and between MS and oligodendroglioma (ODG) (TBRmax ODG vs. MS: p = 0.003; TBRmean ODG vs. MS: p = 0.01). The ability to differentiate between MS and glioma II°-IV° increased from 0.79 using standard TBR analysis to 0.94 using a SVM based machine learning algorithm.

CONCLUSIONS

FET-PET imaging may help differentiate MS from glioma II°-IV° and SVM based machine learning approaches can enhance classification performance.

Dosimetric impact of the positioning variation of tumor treating field electrodes in the PriCoTTF-phase I/II trial

Purpose

The aim of the present study based on the PriCoTTF‐phase I/II trial is the quantification of skin‐normal tissue complication probabilities of patients with newly diagnosed glioblastoma multiforme treated with Tumor Treating Field (TTField) electrodes, concurrent radiotherapy, and temozolomide. Furthermore, the skin‐sparing effect by the clinically applied strategy of repetitive transducer array fixation around their center position shall be examined.

Material and Methods

Low‐dose cone‐beam computed tomography (CBCT) scans of all fractions of the first seven patients of the PriCoTTF‐phase I/II trial, used for image guidance, were applied for the dosimetric analysis, for precise TTField transducer array positioning and contour delineation. Within this trial, array positioning was varied from fixation‐to‐fixation period with a standard deviation of 1.1 cm in the direction of the largest variation of positioning and 0.7 cm in the perpendicular direction. Physical TTField electrode composition was examined and a respective Hounsfield Unit attributed to the TTField electrodes. Dose distributions in the planning CT with TTField electrodes in place, as derived from prefraction CBCTs, were calculated and accumulated with the algorithm Acuros XB. Dose‐volume histograms were obtained for the first and second 2 mm scalp layer with and without migrating electrodes and compared with those with fixed electrodes in an average position. Skin toxicity was quantified according to Lyman's model. Minimum doses in hot‐spots of 0.05 cm² and 25 cm² (ΔD_0.05cm², ΔD_25cm²) size in the superficial skin layers were analyzed.

Results

Normal tissue complication probabilities (NTCPs) for skin necrosis ranged from 0.005% to 1.474% (median 0.111%) for the different patients without electrodes. NTCP logarithms were significantly dependent on patient (P < 0.0001) and scenario (P < 0.0001) as classification variables. Fixed positioning of TTField arrays increased skin‐NTCP by a factor of 5.50 (95%, CI: 3.66–8.27). The variation of array positioning increased skin‐NTCP by a factor of only 3.54 (95%, CI: 2.36–5.32) (P < 0.0001, comparison to irradiation without electrodes; P = 0.036, comparison to irradiation with fixed electrodes). NTCP showed a significant rank correlation with D25cm² over all patients and scenarios (r_s = 0.76; P < 0.0001).

Conclusion

Skin‐NTCP calculation uncovers significant interpatient heterogeneity and may be used to stratify patients into high‐ and low‐risk groups of skin toxicity. Array position variation may mitigate about one‐third of the increase in surface dose and skin‐NTCP by the TTField electrodes.

Preoperative and early postoperative seizures in patients with glioblastoma-two sides of the same coin?

Background

Symptomatic epilepsy is a common symptom of glioblastoma, which may occur in different stages of disease. There are discrepant reports on association between early seizures and glioblastoma survival, even less is known about the background of these seizures. We aimed at analyzing the risk factors and clinical impact of perioperative seizures in glioblastoma.

Methods

All consecutive cases with de-novo glioblastoma treated at our institution between 01/2006 and 12/2018 were eligible for this study. Perioperative seizures were stratified into seizures at onset (SAO) and early postoperative seizures (EPS, ≤21days after surgery). Associations between patients characteristics and overall survival (OS) with SAO and EPS were addressed.

Results

In the final cohort (n = 867), SAO and EPS occurred in 236 (27.2%) and 67 (7.7%) patients, respectively. SAO were independently predicted by younger age (P = .009), higher KPS score (P = .002), tumor location (parietal lobe, P = .001), GFAP expression (≥35%, P = .045), and serum chloride at admission (>102 mmol/L, P = .004). In turn, EPS were independently associated with tumor location (frontal or temporal lobe, P = .013) and pathologic laboratory values at admission (hemoglobin < 12 g/dL, [P = .044], CRP > 1.0 mg/dL [P = 0.036], and GGT > 55 U/L [P = 0.025]). Finally, SAO were associated with gross-total resection (P = .006) and longer OS (P = .030), whereas EPS were related to incomplete resection (P = .005) and poorer OS (P = .009).

Conclusions

In glioblastoma patients, SAO and EPS seem to have quite different triggers and contrary impact on treatment success and OS. The clinical characteristics of SAO and EPS patients might contribute to the observed survival differences.

NIMG-12. 18F-FLUORETHYLTYROSINE POSITRON EMISSION TOMOGRAPHY VERSUS MAGNETIC RESONANCE SPECTROSCOPY IN PREOPERATIVE DETECTION OF NEWLY DIAGNOSED GLIOMAS BY USING MACHINE LEARNING

BACKGROUND

Advanced imaging techniques entered the field of neurooncology. In this analysis we compare the diagnostic potential of 18F-fluorethyltyrosine (FET) positron emission tomography (PET) and magnetic resonance spectroscopy (MRS) in their potential to preoperatively predict certain glioma subtypes.

AIMS

Goal of this analysis ist the evaluation of FET PET and MRS regarding the preoperative prediction of glioma subtypes.

METHODS

We analyzed 33 patients with histopathologically confirmed newly diagnosed glioma. The patients received FET PET and MRS during one single preoperative diagnostic session. According to the molecular portfolio patients were subdivided in IDH wildtype glioblastoma patients (GBM), IDH wildtype WHO grade II/III glioma patients (Astro_IDHwt), IDH mutant WHO grade II/III glioma patients without 1p/19q codeletion (Astro_IDHmut) and with 1p/19q codeletion (ODG). Mean and maximum tumor-to-brain ratio (TBRmean and TBRmax), N-acetylaspartate, choline and creatine peaks were correlated with postoperative tumor diagnosis. To gain generalizable implications we subdivided the study cohort into a development and validation subcohort. A support vector machine model was fitted to the development subcohort and evaluated on the validation subcohort. Receiver operating characteristic curve served to assess model performance.

RESULTS

GBM patients had highest TBRmax and TBRmean values (mean: 3.5 and 3.8) and the ODG patients showed the second highest TBRmax and TBRmean values (mean: 2.6 and 3). The distribution of MRS markers exhibited to clear trend. The performance of glioma subtyping was comparatively low for the TBR values (AUC: 0.68) and even lower for the MRS markers (AUC: 0.60). These results are in line with preliminary investigations performed by our institute for the comparison of 11C-methionine PET with MRS in preoperative glioma subtyping.

CONCLUSIONS

FET PET and MRS bear limited potential in glioma subgrouping. However, FET PET appears to be slightly superior. Investigation in a larger cohort is required to draw definite conclusions.

CTNI-79. PRICOTTF TRIAL: A PHASE I/II TRIAL OF TTFIELDS PRIOR AND CONCOMITANT TO RADIOTHERAPY IN NEWLY DIAGNOSED GLIOBLASTOMA

OBJECTIVE

Survival rates were significantly improved when adding TTFields to adjuvant chemotherapy with temozolomide in patients with newly diagnosed glioblastoma (nGBM) in the phase 3 EF-14 trial. TTFields therapy is applied at 200 kHz by arrays that are placed at the patients’ scalp. In preclinical studies, the combination of TTFields and radiotherapy demonstrated synergistically enhanced efficacy in GBM cells. Here, we present the PriCoTTF trial, which is currently enrolling nGBM patients and will assess the safety and efficacy of TTFields initiated prior and concomitant to radiochemotherapy.

METHODS

After surgery and complete wound-healing, TTFields therapy will be initiated in newly diagnosed GBM patients. TTFields therapy will continue throughout radiochemotherapy and adjuvant chemotherapy for a total of approximately 9 months. Radiotherapy will be conducted through the arrays, by which TTFields therapy is delivered. Totally, thirty-three patients will be enrolled in two arms. In arm A, 20 adult patients will be enrolled to receive normo-fractionated radiotherapy and in arm B, 13 elderly patients will be treated by hypo-fractionated radiotherapy. The patients will receive chemotherapy according to institutional standard and interdisciplinary tumor conference.

RESULTS

Safety and tolerance based on the frequency of pre-specified treatment-limiting toxicities is defined as primary endpoint of the trial. Secondary endpoints include the frequency of adverse events, progression-free survival (PFS), and overall survival (OS). The trial is currently enrolling patients at four sites in Germany. To date, 13 patients were included (May 2020). Initial practical experiences will be presented.

CONCLUSION

The combination of TTFields and radiotherapy is an encouraging approach to further improve survival of GBM patients. In the presented phase I/II trial, the safety and efficacy of TTFields initiated prior and concomitant to RT in newly diagnosed GBM will be assessed. In addition, initial efficacy data (phase II) can serve as a rationale for a randomized phase III trial.

Demographic, radiographic, molecular and clinical characteristics of primary gliosarcoma and differences to glioblastoma

OBJECTIVE

Gliosarcoma (GSC) is a rare histological variant of glioblastoma (GBM). Due to limited evidence regarding clinical, genetic and radiographic characteristics of GSC, this study aimed to analyze independent outcome predictors of GSC, and to address the differences between GSC and GBM concerning the baseline characteristics and patients' survival.

METHODS

Patients treated between 2001 and 2018 for the diagnosis of GBM and GSC were included in this study. Patients' records were reviewed for demographic, clinical, genetic and radiographic characteristics. Univariate, multivariate and propensity score matched analyses were performed.

RESULTS

In the GSC sub-cohort (N = 56), patients' age, preoperative clinical status, midline tumor location and tumor size were found to be independently associated with overall survival. As compared to GBM individuals (N = 1249), a temporal location (p = 0.002), presence of eccentric tumor cysts (p < 0.001), a higher ratio of TP53 staining (p = 0.002) and a lower ratio of GFAP staining (p = 0.005) were characteristic for GSC. The diagnosis of GSC was associated with a poorer survival (p = 0.002) independently of the patients' age, sex, clinical status and extent of resection, However, this association was no more significant, when enhancing the multivariate analysis with molecular-genetic characteristics (IDH1 mutation and MGMT promotor methylation status).

DISCUSSION

Certain radiographic and molecular-genetic patterns present the distinct characteristics of GSC. There is an association between the diagnosis of GSC and a poorer outcome. This difference might be linked to different genetic alterations in GBM and GSC. Prospective studies are needed to further elucidate the characteristics of GSC and develop targeted treatment approaches for this rare variant.

DNA promoter methylation of CCM genes in human cerebral cavernous malformations: Importance of confirming MSP data through sequencing

BACKGROUND

Cerebral cavernous malformations (CCMs) is the second most common cerebrovascular disease and is classified as familial (20%) and sporadic (80%) forms. Loss of function mutation of three CCM genes results in the familial CCM. Considering the similar clinic presentation of familial and sporadic CCMs, and based on enriched CpG islands in the DNA promoter region of three CCM genes, we hypothesized that DNA methylation of the CpG islands of the CCM genes is involved in human CCM, thereby leading to loss of CCM genes.

MATERIAL AND METHODS

69 human CCMs including sporadic (n = 40), multiple (n = 15) and familial (n = 14) cases. DNA was extracted from the surgical specimens of CCMs followed by bisulfite conversion. The methylation status of the promoter regions of three CCM genes was detected by methylation specific PCR (MSP). To confirm the results of MSP, four MSP-positive probes showing CCM3 methylation underwent deep bisulfite sequencing (DBS).

RESULTS

MSP mostly excluded methylation of CCM1 and CCM2 promotor regions (data not shown). In the case of CCM3, 12 out of 55 sporadic cases showed positivity for MSP (21.8%). Deep bisulfite sequencing revealed that four CCM3 MSP positive cases were all negative for DNA methylation.

CONCLUSION

The present study suggests that DNA promotor methylation of CCM1-3 genes is not involved in human family CCMs and that it is important to confirm MSP data with DBS. Further study with higher number of sporadic CCM patients is required for better understanding whether this epigenetic mechanism is involved in the pathology of CCM.

The PRESSURE score to predict decompressive craniectomy after aneurysmal subarachnoid haemorrhage

The prognosis of patients with aneurysmal subarachnoid haemorrhage requiring decompressive craniectomy is usually poor. Proper selection and early performing of decompressive craniectomy might improve the patients’ outcome. We aimed at developing a risk score for prediction of decompressive craniectomy after aneurysmal subarachnoid haemorrhage. All consecutive aneurysmal subarachnoid haemorrhage cases treated at the University Hospital of Essen between January 2003 and June 2016 (test cohort) and the University Medical Center Freiburg between January 2005 and December 2012 (validation cohort) were eligible for this study. Various parameters collected within 72 h after aneurysmal subarachnoid haemorrhage were evaluated through univariate and multivariate analyses to predict separately primary (PrimDC) and secondary decompressive craniectomy (SecDC). The final analysis included 1376 patients. The constructed risk score included the following parameters: intracerebral (‘Parenchymal’) haemorrhage (1 point), ‘Rapid’ vasospasm on angiography (1 point), Early cerebral infarction (1 point), aneurysm Sac > 5 mm (1 point), clipping (‘Surgery’, 1 point), age Under 55 years (2 points), Hunt and Hess grade ≥ 4 (‘Reduced consciousness’, 1 point) and External ventricular drain (1 point). The PRESSURE score (0–9 points) showed high diagnostic accuracy for the prediction of PrimDC and SecDC in the test (area under the curve = 0.842/0.818) and validation cohorts (area under the curve = 0.903/0.823), respectively. 63.7% of the patients scoring ≥6 points required decompressive craniectomy (versus 12% for the PRESSURE < 6 points, P < 0.0001). In the subgroup of the patients with the PRESSURE ≥6 points and absence of dilated/fixed pupils, PrimDC within 24 h after aneurysmal subarachnoid haemorrhage was independently associated with lower risk of unfavourable outcome (modified Rankin Scale >3 at 6 months) than in individuals with later or no decompressive craniectomy (P < 0.0001). Our risk score was successfully validated as reliable predictor of decompressive craniectomy after aneurysmal subarachnoid haemorrhage. The PRESSURE score might present a background for a prospective randomized clinical trial addressing the utility of early prophylactic decompressive craniectomy in aneurysmal subarachnoid haemorrhage.

Seizures at the onset of aneurysmal SAH: epiphenomenon or valuable predictor?

Objective

Seizures at the onset (SAO) of aneurysmal subarachnoid hemorrhage (aSAH) occur in up to one of every five cases. To date, there is no consensus on causal background and clinical value of these early bleeding-related seizures. This study aimed to analyze the predictors and the impact of SAO in aSAH.

Methods

All aSAH patients from the institutional observational cohort (01/2003–06/2016) were retrospectively reviewed. Patients’ charts and emergency protocols from first responders were screened for the occurrence of seizures in the first 24 h after aSAH. Patients’ baseline characteristics and occurrence of post-hemorrhagic complications were analyzed. Outcome endpoints included in-hospital mortality and poor outcome at 6-month follow-up (modified Rankin Scale > 3).

Results

Of 984 patients included in the final analysis, SAO occurred in 93 cases (9.5%) and were independently associated with younger age (< 51 years, p < 0.001), WFNS grade ≥ 4 (p < 0.001), aneurysm characteristics (location at the proximal branch of the anterior cerebral artery [p = 0.037] and irregular sac [p = 0.019]) and admission body temperature > 38.3 ℃ (p = 0.008). There was an association between SAO and early complications (early infarcts [p = 0.004] and primary decompressive craniectomy [p = 0.024]). Only in the subgroup analysis restricted to the younger individuals, SAO independently predicted poor outcome of aSAH (p = 0.002).

Significance

Onset seizures following aSAH are rare and most likely related to the severity of early brain injury. Particularly, younger individuals are not only at higher risk for SAO, but are also prone to poor outcome in case of aSAH accompanied with SAO.

Trial registration number

German clinical trial registry (DRKS, unique identifier: DRKS00008749, 06/09/2015)

The influence of subventricular zone involvement in extent of resection and tumor growth pattern of glioblastoma

Objectives

Isocitrate dehydrogenase (IDH1/2) mutations and O6-alkylguanine DNA methyltransferase (MGMT) promoter methylations are acknowledged survival predictors in patients with glioblastoma (GB). Moreover, tumor growth patterns like multifocality and subventricular zone (SVZ) involvement seem to be associated with poorer outcomes. Here, we wanted to evaluate the influence of the SVZ involvement and the multifocal tumor growth on the extent of surgical resection and its correlation with overall survival (OS) and molecular characteristics of patients with GB.

Methods

Adult patients with primary GB who underwent surgery at our department between 2012 and 2014 were included. Preoperative magnetic resonance imaging findings were analyzed with regard to tumor location, presence of multifocality and SVZ involvement. The extent of surgical resection as well as clinical and molecular parameters was collected from electronic patient records. Univariate and multivariate analyses were performed.

Results

Two hundred eight patients were retrospectively analyzed, comprising 90 (43.3%) female individuals with a mean age of 62.9 (±12.26) years and OS of 10.2 months (±8.9). Unifocal tumor location was a predictor for better OS with a mean of 11.4 (±9.4) months (vs. 8.0 [±7.4] months, p=0.008). Affection of the SVZ was also associated with lower surgical resection rates (p<0.001). SVZ involvement revealed with 7.8 (±7.0) months a significant worse OS [vs. 13.9 (±10.1) months, p<0.001]. All six IDH1/2 wildtype tumors showed an unifocal location (p=0.066). MGMT promoter methylation was not associated with multifocal tumor growth (p=0.649) or SVZ involvement (p=0.348). Multivariate analysis confirmed independent association between the SVZ involvement and OS (p=0.001).

Conclusion

The involvement of the SVZ appears to have an influence on a lower resection rate of GB. This negative impact of SVZ on GB outcome might be related to lesser extent of resection, higher rates of multifocality and greater surgical morbidity but not inevitably to IDH1/2 mutation and MGMT promoter methylation status.

Abstract CT106: PriCoTTF trial: A phase I/II trial of TTFields prior and concomitant to radiotherapy in newly diagnosed glioblastoma

Objective: The EF-14 trial demonstrated significantly improved survival rates when adding Tumor Treating Fields (TTFields) to adjuvant chemotherapy with temozolomide (TMZ) in patients with newly diagnosed glioblastoma (GBM). In GBM patients, TTFields therapy at 200 kHz is delivered by transducer arrays that are applied to the patients' scalp. In preclinical settings, the combined treatment with TTFields and radiotherapy demonstrated synergistically enhanced efficacy in GBM cells. The presented PriCoTTF trial is currently enrolling and will evaluate the safety and efficacy of TTFields initiated prior and concomitant to combined radiochemotherapy in newly diagnosed GBM.

Methods: After complete wound-healing following surgery, TTFields therapy will be initiated in newly diagnosed GBM patients. TTFields therapy will continue throughout radiochemotherapy and adjuvant chemotherapy for a total of 9 months. Radiotherapy will be applied through the transducer arrays that mediate TTFields therapy. In total, thirty-three patients will be enrolled in two arms. In arm A, 20 adult patients will be enrolled to receive normofractionated radiotherapy whereas in Arm B, 13 elderly patients will be treated by hypofractionated radiotherapy. Chemotherapy will be applied according to institutional standard and interdisciplinary tumor conference.

Results: The primary endpoint of the trial is safety and tolerance based on the frequency of prespecified treatment-limiting toxicities. Secondary endpoints consist in particular of the frequency of adverse events, progression-free survival (PFS) and overall survival (OS). The trial is currently enrolling patients at four centers in Germany with 12 patients included at the time of abstract submission (January 2020). First practical experiences will be presented at the annual AACR meeting.

Conclusion: The combination of TTFields and radiotherapy is a promising approach to improve survival of GBM patients further. This phase I/II trial will evaluate the safety and efficacy of TTFields initiated prior and concomitant to RT in newly diagnosed GBM. Moreover, the first data obtained on efficacy (phase II) will serve as a basis for a randomized phase III trial.

Citation Format: Sied Kebir, Lazaros Lazaridis, Teresa Schmidt, Christoph Oster, Daniela Pierscianek, Nika Guberina, Christoph Kleinschnitz, Martin Proescholdt, Peter Hau, Anca-Ligia Grosu, Ulrich Sure, Björn Scheffler, Martin Stuschke, Martin Glas. PriCoTTF trial: A phase I/II trial of TTFields prior and concomitant to radiotherapy in newly diagnosed glioblastoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT106.

Pathophysiology of Intracranial Aneurysms

Background and Purpose:

The pathophysiology of development, growth, and rupture of intracranial aneurysms (IAs) is only partly understood. Cyclooxygenase 2 (COX-2) converts arachidonic acid to prostaglandin H 2 , which, in turn, is isomerized to prostaglandin E 2 . In the human body, COX-2 plays an essential role in inflammatory pathways. This explorative study aimed to investigate COX-2 expression in the wall of IAs and its correlation to image features in clinical (1.0T, 1.5T, and 3.0T) magnetic resonance imaging (MRI) and ultra-high-field 7T MRI.

Methods:

The study group comprised 40 patients with partly thrombosed saccular IAs. The cohort included 17 ruptured- and 24 unruptured IAs, which had all been treated microsurgically. Formaldehyde-fixed paraffin-embedded samples were immunohistochemically stained with a monoclonal antibody against COX-2 (Dako, Santa Clara, CA; Clone: CX-294). We correlated Perls Prussian blue staining, MRI, and clinical data with immunohistochemistry, analyzed using the Trainable Weka Segmentation algorithm.

Results:

Aneurysm dome size ranged between 2 and 67 mm. The proportion of COX-2 positive cells ranged between 3.54% to 85.09%. An upregulated COX-2 expression correlated with increasing IA dome size ( P =0.047). Furthermore, there was a tendency of higher COX-2 expression in most ruptured IAs ( P =0.064). At all field strengths, MRI shows wall hypointensities due to iron deposition correlating with COX-2 expression ( P =0.022).

Conclusions:

Iron deposition and COX-2 expression in IAs walls correlate with signal hypointensity in MRI, which might, therefore, serve as a biomarker for IA instability. Furthermore, as COX-2 was also expressed in small unruptured IAs, it could be a potential target for specific medical treatment.

The predominant expression of cancer stem cell marker ALDH1A3 in tumor infiltrative area is associated with shorter overall survival of human glioblastoma

Background

ALDH1A3 is a cancer stem cell marker in neoplasms including glioblastoma (GBM). However, the comprehensive role of ALDH1A3 in GBM remains unclear. This study attempted to investigate the expression of ALDH1A3 in human GBM tissues and its association with clinical parameters.

Methods

Thirty primary GBM and 9 control were enrolled in this study. ALDH1A3 mRNA and protein expression levels were detected by RT²-PCR and western blot, respectively. Immunohistochemistry and immunofluorescence staining were performed to evaluate the regional and cellular expression manner of ALDH1A3. The association of ALDH1A3 expression with multiple clinical parameters was analyzed.

Results

ALDH1A3 protein level, but not mRNA level, in a subgroup of GBM was significantly higher than that in the control group. ALDH1A3 immunoreactivity was detected heterogeneously in individual GBMs. Fifteen of 30 cases showed a positive of ALDH1A3 immunoreactivity which was predominantly observed in the tumor infiltrative area (TI). Double immunofluorescence staining revealed a co-localization of ALDH1A3 with GFAP in glial-shaped cells and in tumor cells. ALDH1A3 immunoreactivity was often merged with CD44, but not with CD68. Moreover, ALDH1A3 expression was positively associated with the tumor edema grade and inversely with overall survival (OS) (median OS: 16 months vs 10 months), but with neither MGMT promoter methylation status nor Ki67 index in GBM. An upregulation of ALDH1A3 was accompanied by a reduced expression of STAT3β and p-STAT3β.

Conclusions

Inter- and intra-tumoral heterogeneous expression of ALDH1A3 was exhibited in GBMs. A high immunoreactivity of ALDH1A3 in tumor infiltrative area was associated with shorter OS, especially in patients with MGMT promoter methylation. Our findings propose ALDH1A3 not only as a predictive biomarker but also as a potential target for personalized therapy of GBM.

In the wall lies the truth: a systematic review of diagnostic markers in intracranial aneurysms

OBJECTIVE

Despite recent advances in molecular biology and genetics, the development of intracranial aneurysms (IA) is still poorly understood. Elucidation of the processes occurring in the IA wall is essential for a better understanding of IA pathophysiology. We sought to analyze the current evidence from histological, molecular and genetic studies of IA.

METHODS

We systematically searched PubMed, Scopus, Web of Science and Cochrane Library for articles published before Mar 1, 2019 reporting on different diagnostic markers in human IA specimens. Expression of the markers in IA wall (vs. healthy arterial wall) and association with the rupture status were analyzed. The quality of the included studies and the level of the evidence for the markers were incorporated into the final data assessment.

RESULTS

We included 123 studies reporting on analyses of 3476 IA (median 19 IA/study) published between 1966 and 2018. Based on microscopic, biochemical, genetic and biomechanical analyses, data on 358 diagnostic targets in the IA wall were collected. We developed a scale to distribute the diagnostic markers according to their specificity for IA or healthy arterial wall, as well as for ruptured or unruptured IA. We identified different functional pathways, which might reflect the intrinsic and extrinsic processes underlying IA pathophysiology.

CONCLUSIONS

Multiple histological and molecular markers and the related functional pathways contributing to the development of IA might present promising targets for future therapeutic interventions. Because of small numbers of IA samples in each study, 89% of the analyzed diagnostic markers presented with the lowest level of evidence. This underlines the need for the initiation of a multi-centric prospective histological IA register for pooled data analysis.

Combined radiotherapy and concurrent tumor treating fields (TTFields) for glioblastoma: Dosimetric consequences on non-coplanar IMRT as initial results from a phase I trial

Background

Glioblastoma is a rapidly proliferating tumor. Patients bear an inferior prognosis with a median survival time of 14-16 months. Proliferation and repopulation are a major resistance promoting factor for conventionally fractionated radiotherapy. Tumor-Treating-Fields (TTFields) are an antimitotic modality applying low-intensity (1-3 V/cm), intermediate-frequency (100-300 kHz) alternating electric-fields. More recently interference of TTFields with DNA-damage-repair and synergistic effects with radiotherapy were reported in the preclinical setting. This study aims at examining the dosimetric consequences of TTFields applied during the course of radiochemotherapy.

Methods

Cone-beam-computed-tomography (CBCT)-data from the first seven patients of the PriCoTTF-phase-I-trial were used in a predefined way for dosimetric verification and dose-accumulation of the non-coplanar-intensity-modulated-radiotherapy (IMRT)-treatment-plans as well as geometric analysis of the transducer-arrays by which TTFields are applied throughout the course of treatment. Transducer-array-position and contours were obtained from the low-dose CBCT’s routinely made for image-guidance. Material-composition of the electrodes was determined and a respective Hounsfield-unit was assigned to the electrodes. After 6D-fusion with the planning-CT, the dose-distribution was recalculated using a Boltzmann-equation-solver (Acuros XB) and a Monte-Carlo-dose-calculation-engine.

Results

Overdosage in the scalp in comparison to the treatment plan without electrodes stayed below 8.5% of the prescribed dose in the first 2 mm below and also in deeper layers outside 1cm² at highest dose as obtained from dose-volume-histogram comparisons. In the clinical target volume (CTV), underdosage was limited to 2.0% due to dose attenuation by the electrodes in terms of D95 and the effective-uniform-dose. Principal-component-analysis (PCA) showed that the first principal-position-component of the variation of repeated array-placement in the direction of the largest variations and the perpendicular second-component spanning a tangential plane on the skull had a standard deviation of 1.06 cm, 1.23 cm, 0.96 cm, and 1.11 cm for the frontal, occipital, left and right arrays for the first and 0.70 cm, 0.71 cm, 0.79 cm, and 0.68 cm, respectively for the second-principal-component. The variations did not differ from patient-to-patient (p > 0.8, Kruskal-Wallis-tests). This motion led to a diminution of the dosimetric effects of the electrodes.

Conclusion

From a dosimetric point of view, dose deviations in the CTV due to transducer-arrays were not clinically significant in the first 7 patients and confirmed feasibility of combined adjuvant radiochemotherapy and concurrent TTFields.

PriCoTTF Trial: A phase I/II trial of TTFields prior and concomitant to radiotherapy in newly diagnosed glioblastoma.

DRKS-ID: DRKS00016667.

Date of Registration in DRKS: 2019/02/26.

Investigator Sponsored/Initiated Trial (IST/IIT): yes.

Ethics Approval/Approval of the Ethics Committee: Approved.

(leading) Ethics Committee Nr.: 18–8316-MF, Ethik-Kommission der Medizinischen.

Fakultät der Universität Duisburg-Essen.

EUDAMED-No. (for studies acc. to Medical Devices act): CIV-18-08-025247.

Post-treatment Antiplatelet Therapy Reduces Risk for Delayed Cerebral Ischemia due to Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Delayed cerebral ischemia (DCI) has a strong impact on outcome of patients with aneurysmal subarachnoid hemorrhage (SAH). Positive effect of antiplatelet therapy on DCI rates has been supposed upon smaller SAH series.

OBJECTIVE

To analyze the benefit/risk profile of antiplatelet use in SAH patients.

METHODS

This retrospective case-control study was based on institutional observational cohort with 994 SAH patients treated between January 2003 and June 2016. The individuals with postcoiling antiplatelet therapy (aspirin with/without clopidogrel) were compared to a control group without antiplatelet therapy. Occurrence of DCI, major/minor bleeding events in the follow-up computed tomography scans, and favorable outcome at 6 mo after SAH (modified Rankin scale < 3) were compared in both groups.

RESULTS

Of 580 patients in the final analysis, 329 patients received post-treatment antiplatelet medication. There were no significant differences between the compared groups with regard to basic outcome confounders. Aspirin use was independently associated with reduced DCI risk (P < .001, adjusted odds ratio = 0.41, 95% confidence interval 0.24-0.65) and favorable outcome (P = .02, adjusted odds ratio = 1.78, 95% confidence interval 1.06-2.98). Regarding bleeding complications, aspirin was associated only with minor bleeding events (P = .02 vs P = .51 for major bleeding events).

CONCLUSION

Regular administration of aspirin might have a positive impact on DCI risk and outcome of SAH patients, without increasing the risk for clinically relevant bleeding events. In our SAH cohort, dual antiplatelet therapy showed no additional benefit on DCI risk, but increased the likelihood of major bleeding events.

Does the expression of glial fibrillary acid protein (GFAP) stain in glioblastoma tissue have a prognostic impact on survival?

OBJECTIVE

Several parameters are known to predict the survival of glioblastoma (GB), including extent of resection and MGMT promotor methylation. Staining for glial fibrillary acidic protein (GFAP) is a common component of routine histological work-up, but its clinical utility in GB is unclear. The aim of the present study was to analyze the predictive value of quantitative GFAP measurements for survival of patients with GB.

METHODS

All subjects in our institutional database of patients with primary GB who underwent surgery between 2011 and 2014 with examination of immunohistochemical staining of GFAP were included. Percentage GFAP staining was measured in 5% increments (5-100%). Univariate and multivariate analyses were performed between GFAP values and survival data. Clinically relevant cut-offs for GFAP staining were identified by receiver operating characteristic (ROC) curves.

RESULTS

The final cohort consisted of 272GB patients with available quantitative GFAP measurements (mean age, 62 (±11.1) years, 117 females [43%]). Overall survival was 11.4 months (±8.6). Median GFAP value was 70% (range, 5-100%). The ROC curve showed the clinically relevant cut-off for GFAP at 75% (area under the curve: 0.691). Accordingly, GB patients with GFAP≥75% presented poorer survival on Kaplan-Meier survival estimation (P=0.021). Multivariate analysis adjusted for age, extent of resection, preoperative Karnofsky performance status scale, IDH1 mutation and MGMT methylation status confirmed the independent predictive value of GFAP≥75% for overall survival (P=0.032). Finally, patients with GFAP≥75% showed significantly poorer long-term survival than those with GFAP<75%: 5.8% vs. 15.2% (P=0.0183) and 0.8% vs. 8% (P=0.0076) for 2- and 3-year survival, respectively.

CONCLUSION

Quantitative immunohistochemical assessment of GFAP staining could provide a novel biomarker for overall and especially long-term survival of patients with GB. Prospective multi-center validation of the prognostic value of GFAP for GB survival is needed.

The SHORT Score for Preoperative Assessment of the Risk for Short-Term Survival in Glioblastoma

BACKGROUND

Despite recent improvements in treatment of glioblastoma (GBM), some patients still have a short survival. We sought to develop a new risk score for preoperative assessment of short-term survival (STS) (<6 months) in patients with GBM.

METHODS

All adult patients who underwent surgical resection of GBM between 2004 and 2014 were included (N = 379). Demographic and clinical parameters, which were available at admission, were assessed. Variables were evaluated in univariate and multivariate analyses. The score was validated in a separate cohort of patients with GBM who underwent surgical resection between 2015 and 2018.

RESULTS

The following independent predictors of STS were integrated into a new score: body height (<169 cm, 1 point), arterial hypertension (1 point), age (≤54 years, 0 points; 55-74 years, 1 points; ≥75 years, 2 points), and poor clinical status (Karnofsky performance scale [KPS] score: ≤60%, 2 points; 70%-80%, 1 point; ≥90%, 0 points). The new risk score, SHORT (Small body height, Hypertension, Older age, Reduced KPS score, short-Term survival), ranged from 0 to 6 points and showed good accuracy of risk estimation for STS in GBM (area under the curve: 0.715). STS rates were 9.7%, 23.1%, and 70% in patients with GBM scoring <2 points, 2-4 points, and >4 points (P < 0.0001). The score was successfully validated (area under the curve: 0.770).

CONCLUSIONS

This study presents the SHORT score for preoperative assessment of STS risk in patients with GBM. This risk score needs external validation in larger patient cohorts from other institutions. Our score might be a tool to facilitate treatment decisions in patients with GBM before surgery.

Preoperative Survival Prediction in Patients With Glioblastoma by Routine Inflammatory Laboratory Parameters

BACKGROUND

Glioblastoma (GBM) is the most common malignant brain tumor in adults and still carries a dismal prognosis. As several studies detected a connection between inflammation and GBM prognosis, we sought to explore possible associations between routinely investigated inflammatory parameters and GBM outcome.

PATIENTS AND METHODS

Patients treated for GBM at our Institution between 2004 and 2014 were included. White blood cell count (WBC), C-reactive protein (CRP) and the ratio of platelets and WBC (Plt/WBC) were evaluated preoperatively. Medical records were reviewed for clinical parameters (age, sex, preoperative clinical condition, genetic alterations). Study endpoints were overall (OS) and 1- and 2-year survival.

RESULTS

In the final cohort consisting of 565 individuals with GBM, univariate analysis showed significant associations for WBC, CRP and Plt/WBC ratio with OS. Kaplan-Meier survival plot confirmed significantly poorer OS in patients with WBC>12/nl and with CRP≥2.9 mg/dl. In multivariate analysis, a WBC of >12/nl was an independent prognostic factor for all three outcome parameters and CRP≥2.9 mg/dl for OS and 1-year survival.

CONCLUSION

Preoperative WBC and CRP values were confirmed as independent predictors of GBM outcome. This emphasizes the need for further evaluation of the role of inflammation in the prognosis of GBM.

Macrophages/Microglia Represent the Major Source of Indolamine 2,3-Dioxygenase Expression in Melanoma Metastases of the Brain

The manifestation of brain metastases in patients with advanced melanoma is a common event that limits patient's survival and quality of life. The immunosuppressive properties of the brain parenchyma are very different compared to the rest of the body, making it plausible that the current success of cancer immunotherapies is specifically limited here. In melanoma brain metastases, the reciprocal interplay between immunosuppressive mediators such as indoleamine 2, 3-dioxygenase (IDO) or programmed cell death-ligand 1 (PD-L1) in the context of neoplastic transformation are far from being understood. Therefore, we analyzed the immunoreactive infiltrate (CD45, CD3, CD8, Forkhead box P3 [FoxP3], CD11c, CD23, CD123, CD68, Allograft Inflammatory factor 1[AIF-1]) and PD-L1 with respect to IDO expression and localization in melanoma brain metastases but also in matched metastases at extracranial sites to correlate intra- and interpatient data with therapy response and survival. Comparative tissue analysis identified macrophages/microglia as the major source of IDO expression in melanoma brain metastases. In contrast to the tumor infiltrating lymphocytes, melanoma cells per se exhibited low IDO expression levels paralleled by cell surface presentation of PD-L1 in intracranial metastases. Absolute numbers and pattern of IDO-expressing cells in metastases of the brain correlated with recruitment and localization of CD8⁺ T cells, implicating dynamic impact on the regulation of T cell function in the brain parenchyma. However, paired analysis of matched intra- and extracranial metastases identified significantly lower fractions of cytotoxic CD8⁺ T cells in intracranial metastases while all other immune cell populations remain unchanged. In line with the already established clinical benefit for PD-L1 expression in extracranial melanoma metastases, Kaplan-Meier analyses correlated PD-L1 expression in brain metastases with favorable outcome in advanced melanoma patients undergoing immune checkpoint therapy. In summary, our data provide new insights into the landscape of immunosuppressive factors in melanoma brain metastases that may be useful in the implication of novel therapeutic strategies for patients undergoing cancer immunotherapy.

TET2 promotor methylation and TET2 protein expression in pediatric posterior fossa ependymoma

Pediatric posterior fossa ependymoma (PF) is one of the most common brain tumors in children. Recently, two subtypes of PF were identified. PF-A has a dismal prognosis and shows a hypermethylation phenotype, whereas PF-B shows a great genomic instability. The ten-eleven translocation methylcytosine dioxygenase 2 (TET2) gene (TET2) has been linked to the regulation of DNA methylation. We analyzed TET2 promotor methylation and protein expression to assess the role of TET2 in PF. Medical records of all PF cases treated in our institution between 1993 and 2015 were evaluated regarding tumor histology, grade, tumor location, gender, age, tumor recurrence, distant metastasis, survival and time to progression. Subsequently, we analyzed TET2 promotor methylation using methylation-specific polymerase chain reaction. TET2 protein expression was assessed using immunohistochemistry. Low TET2 expression was detected in seven of 17 cases. There was an association between low TET2 expression and tumor recurrence (P = 0.049). A TET2 promotor methylation was detected in five of 10 cases. There was no association between the TET2 promotor methylation with recurrence, tumor grade or gender. TET2 promotor methylation and low TET2 expression was detected in a subgroup of PF. Our data show an association between low TET2 expression and tumor recurrence in PF.

A rare case of a completely thrombosed bilobed giant intracranial aneurysm of the anterior cerebral artery with spontaneous parent vessel thrombosis: case report

Background

A huge spherical intracranial mass can sometimes be misdiagnosed, due to the lack of typical radiographic features. Thrombosed giant intracranial aneurysms (GIAs) are an uncommon but still a possible differential diagnosis that must be kept in mind to guarantee the best surgical approach and resection of the lesion. We describe an extremely rare case of a huge bifrontal mass mimicking a cystic echinococcosis, in which the surgery unveiled a completely thrombosed GIA of the left anterior cerebral artery (ACA).

Case presentation

A 61-year-old patient complained about intermittent weakness of the right leg, mild holocephalic headache, beginning cognitive deficits and lethargy. Magnetic resonance imaging (MRI) showed a huge partially calcified and bilobed frontal mass with peripheral edema. Based on a time-resolved angiography with interleaved Stochastic trajectories MRI (TWIST-MRI), a vascular origin of the lesion was considered unlikely. Therefore, the surgery was performed under the suspicion of a cystic echinococcosis but revealed a bilobed GIA of the left ACA with a parent vessel thrombosis. Although only a limited left frontal craniotomy was performed, a proximal control of the parent vessel could be ensured, and the aneurysm was successfully clipped. The patient showed postoperatively no new neurological deficits.

Conclusions

Completely thrombosed GIAs with parent vessel thrombosis are rare lesions that might be misdiagnosed if typical radiographic features are missing. Thus, in case of an intracranial spherical mass with signs of intralesional hemorrhage and mural calcifications, presence of a completely thrombosed GIA should be considered as a possible differential diagnosis.

RARE-39. COMBINATION OF TUMOR TREATING FIELDS (TTFIELDS) WITH LOMUSTINE (CCNU) AND TEMOZOLOMIDE (TMZ) IN NEWLY DIAGNOSED GLIOBLASTOMA (GBM) PATIENTS - A BI-CENTRIC ANALYSIS

BACKGROUND

TTFields combined with TMZ chemotherapy demonstrated significantly improved PFS, OS and long-term survival in newly diagnosed glioblastoma (ndGBM) patients in the EF-14 trial; independent of MGMT-promoter methylation-status, age, grade of resection, and performance status. Recently, improved efficacy of lomustine/TMZ compared to TMZ monotherapy in ndGBM patients with MGMT-promotor methylation was reported in the CeTeG trial. As TTFields demonstrated a favorable safety profile as well as a high potential for being combined with other modalities and the encouraging results for methylated MGMT-promoter GBM patients in the CeTeG trial, there is a strong rationale for combining these treatment regimens. Here, we present a case series of patients receiving a combination of TTFields and lomustine/TMZ.

METHODS

Patients with ndGBM and MGMT-promoter methylation underwent combined therapy of TTFields plus lomustine/TMZ after surgery and radiochemotherapy. MGMT-promoter status was measured by pyrosequencing. Safety, feasibility, and first efficacy results are reported at data cut-off (April 26, 2019).

RESULTS

Sixteen patients with MGMT-promoter methylated ndGBM (median, range: age 50, 27–70; KPS 90, 60–100) have been treated with a combination of TTFields plus lomustine/TMZ. The analysis included patients with complete resection (n=7), partial resection (n=8), as well as biopsy (n=1). CTCAE grade 3 hematotoxicity was observed in seven patients (44%) but was unlikely related to the addition of TTFields to lomustine/TMZ. Medical device site reactions (low-grade skin reactions) were detected in six patients (38%). At data cut-off, the analyzed patient population demonstrated a median PFS of 20 months; the median OS was not yet reached.

CONCLUSION

The results of this analysis indicate that the combination of TTFields/lomustine/TMZ is safe and feasible. Moreover, the observed survival outcomes point to preliminary beneficial effects of the triple combination. Additional follow-up and increased sample size are required and planned for further safety and efficacy assessment of this treatment regimen.

Simultaneous primary cancer occurrence of melanoma and pulmonary adenocarcinoma in leptomeningeal metastases: a case report

Background

Leptomeningeal metastasis (LM) is a predominantly late stage, devastating complication of a variety of malignant solid tumors. Diagnosis relies predominantly on neurological, radiographic, and cerebrospinal fluid (CSF) assessments. Recently, liquid biopsy tests derived from CSF has shown to be a feasible, noninvasive promising approach to tumor molecular profiling for proper brain cancer diagnostic treatment, thereby providing an opportunity for CSF-based personalized medicine. However, LM is typically misleadingly assumed to originate from only one primary tumor type.

Case presentation

In this case report, we provide first evidence of the co-occurrence of LM originating from more than one primary tumor types.

Discussion and conclusions

Based on this patient case profile, the co-occurrence of LM from two or more primary tumor types should be accounted for when deriving diagnostic conclusions from liquid biopsy tests.

Treatment allocation of ruptured anterior communicating artery aneurysms: The influence of aneurysm morphology

OBJECTIVES

Since publication of the ISAT study, the majority of neurovascular centers adhere to "coil first" policy for patients with subarachnoid hemorrhage (SAH). However, final allocation in favor of coiling or clipping is based on anatomic features of ruptured intracranial aneurysms with respect to clinical characteristics of SAH. In this study, we analyzed the parameters relevant for treatment allocation of ruptured anterior communicating artery aneurysms (AComAA).

PATIENTS AND METHODS

From our institutional SAH database, all cases with ruptured AComAA, which underwent diagnostic subtraction angiography (DSA) with subsequent treatment allocation, were included. The radiographic features of AComAA were collected from pre-treatment DSA. In addition, demographic, clinical and radiographic parameters of SAH were recorded. The variables selected through univariate analyses were subsequently evaluated using multivariate regression analysis.

RESULTS

Of 300 SAH patients in the final analysis, the majority of the cases underwent endovascular coiling (n = 221, 73.7%). The following aneurysm features were associated with treatment modality in the univariate analysis: maximal sack size (p = 0.034), perpendicular height (p = 0.007), aspect ratio (p < 0.001) and sack/neck-ratio (p = 0.001). Accordingly, the following cutoffs for these variables were defined upon the receiver operating characteristics curves: 5 mm for sack size, 6 mm for perpendicular height, 1.6 for aspect ratio and sack/neck-ratio. In the multivariate analysis, aspect ratio of 1.6 was the only independent predictor of treatment allocation (p = 0.005; aOR = 2.57; 95% CI 1.33-4.96), which remained significant (p = 0.003; aOR = 2.77; 95% CI 1.41-5.45) after adjusting for patients' age, WFNS & Fisher grades, as well as intracerebral hematoma volume.

CONCLUSION

Although not-routinely assessed during initial allocation treatment, our retrospective analysis proved that aspect ratio is a reliable predictor of treatment allocation of ruptured AComAA. Except for large space-occupying ICH commonly obligating the microsurgical treatment, other clinical and radiographic characteristics of SAH do not seem to be of clinical relevance for the selection of treatment modality.

Endovascular treatment of cerebral vasospasm after subarachnoid hemorrhage

Objective

Delayed cerebral ischemia (DCI) is strongly associated with poor outcome after subarachnoid hemorrhage (SAH). Cerebral vasospasm is a major contributor to DCI and requires special attention. To evaluate the effect of vasospasm management on SAH outcome, we performed a pooled analysis of 2 observational SAH cohorts.

Materials

Data from 2 institutional databases with consecutive patients with SAH treated between 2005 and 2012 were pooled. The effect of 2 institutional standards of conservative and endovascular vasospasm treatment (EVT) on the rates of DCI (new cerebral infarcts not visible on the post-treatment imaging) and unfavorable outcome (modified Rankin Scale score >2) at 6 months follow-up was analyzed.

Results

The final analysis included 1,057 patients with SAH. There was no difference regarding demographic (age and sex), clinical (Hunt & Hess grades, acute hydrocephalus, treatment modality, and infections), and radiographic (Fisher grades and aneurysm location) characteristics of the populations. However, there was a significant difference in the rate (24.4% [121/495] vs 14.4% [81/562], p < 0.0001) and timing (first treatment on day 6 vs 8.9 after SAH, p < 0.0001) of EVT. The rates of DCI (20.8% vs 29%, p = 0.0001) and unfavorable outcome (44% vs 50.6%, p = 0.04) were lower in the cohort with more frequent and early EVT. Multivariate analysis confirmed independent effect of EVT standard on DCI risk and outcome.

Conclusions

A preventive strategy utilizing frequent and early EVT seems to reduce the risk of DCI in patients with SAH and improve their functional outcome. We recommend prospective evaluation of the value of preventive EVT strategy on SAH.

Classification of evidence

This study provides Class III evidence that for patients with SAH, a frequent and early EVT to treat vasospasm reduces the risk of DCI and improves functional outcome.

Intracranial Aneurysms in Sickle Cell Disease

Background:

The exact causes of intracranial aneurysms (IAs) are still unknown. However, certain diseases are known to be associated with IAs.

Objective:

To analyze the differences in IA characteristics in the general population and in individuals with sickle-cell disease (SCD).

Methods:

We systematically searched PubMed, Scopus, Web of Science, and Cochrane Library for Data on SCD patients with IAs. We compared IA characteristics of SCD patients with those from 2451 healthy IA carriers from our observational cohort.

Results:

129 SCD patients with IAs were identified in 42 studies. The SCD patient cohort was characterized by younger age (mean 27.1 vs 54.9 years, p<0.0001) and lower female prevalence (57.7% vs 68.4%, p=0.0177). The prevalence (47% vs 34.5%, p=0.004) and the number (3.02 vs 2.56 IAs/patient, p=0.004) of multiple IAs were also higher in the SCD cohort. Unruptured IAs (3.27 vs 6.16 mm, p<0.0001), but not ruptured IAs (7.8 vs 7.34 mm, p=0.9086) were significantly smaller in the SCD cohort. In addition, IAs were more frequently located in the internal carotid artery (45% vs 29%, p<0.0001) or posterior circulation (43% vs 20%, p<0.0001). Higher age (≥30 years, p=0.007), IA size ≥7 mm (p=0.008), and location in posterior circulation (p=0.01) were independently associated with subarachnoid hemorrhage in SCD.

Conclusion:

There is a distinct demographic and radiographic pattern of IA in SCD. Risk factors for IA rupture in SCD are mostly congruent with those in healthy individuals.