Mass Effect Deformation Heterogeneity (MEDH) on Gadolinium-contrast T1-weighted MRI is associated with decreased survival in patients with right cerebral hemisphere Glioblastoma: A feasibility study

Subtle tissue deformations caused by mass-effect in Glioblastoma (GBM) are often not visually evident, and may cause neurological deficits, impacting survival. Radiomic features provide sub-visual quantitative measures to uncover disease characteristics. We present a new radiomic feature to capture mass effect-induced deformations in the brain on Gadolinium-contrast (Gd-C) T1w-MRI, and their impact on survival. Our rationale is that larger variations in deformation within functionally eloquent areas of the contralateral hemisphere are likely related to decreased survival. Displacements in the cortical and subcortical structures were measured by aligning the Gd-C T1w-MRI to a healthy atlas. The variance of deformation magnitudes was measured and defined as Mass Effect Deformation Heterogeneity (MEDH) within the brain structures. MEDH values were then correlated with overall-survival of 89 subjects on the discovery cohort, with tumors on the right (n = 41) and left (n = 48) cerebral hemispheres, and evaluated on a hold-out cohort (n = 49 subjects). On both cohorts, decreased survival time was found to be associated with increased MEDH in areas of language comprehension, social cognition, visual perception, emotion, somato-sensory, cognitive and motor-control functions, particularly in the memory areas in the left-hemisphere. Our results suggest that higher MEDH in functionally eloquent areas of the left-hemisphere due to GBM in the right-hemisphere may be associated with poor-survival.

Diffusion Tensor Imaging with Fluorescein Sodium Staining in the Resection of High-Grade Gliomas in Functional Brain Areas

OBJECTIVE

To evaluate the feasibility and clinical value of magnetic resonance diffusion tensor imaging (DTI) with fluorescein sodium staining (FLS) in the resection of high-grade glioma (HGG) in functional brain areas.

METHODS

Retrospective cohort study design. The data of 95 patients who underwent surgery at the First Affiliated Hospital of Zhengzhou University for HGG in functional brain areas from October 2014 to December 2017 were investigated. In the observation group, 49 patients underwent DTI preoperatively and received FLS for the removal of tumor during the operation. In the control group, 46 patients received the routine method. All patients were subjected to enhanced magnetic resonance imaging to assess the extent of tumor resection within 72 hours after operation. The changes in muscle strength and Karnofsky Performance Status Scale (KPS) scores were evaluated 1 month after surgery.

RESULTS

The extent of resection was significantly higher in the observation group than in the control group (83.7% vs. 45.7%, respectively; P < 0.001). The rate of muscle strength reduction after surgery was remarkably lower in the observation group than in the control group (20.4% vs. 47.8%, respectively; P = 0.005). KPS scores were higher in the observation group than in the control group (73.5% vs. 47.8%, respectively; P = 0.029). In the observation group, the sensitivity of FLS in identifying tumor tissue was 91.7% (44/48), with a specificity of 90.0% (45/50).

CONCLUSIONS

The application of DTI with FLS can facilitate the maximum resection of HGG in functional brain areas with minimum loss of fiber tracts, reduce the disability rate, and improve quality of postoperative life compared with traditional glioma surgery.

Fluorescence guided surgery by 5-ALA and intraoperative MRI in high grade glioma: a systematic review

PURPOSE

Fluorescence guided surgery by 5-aminolevulinic acid (5-ALA) and intraoperative MRI (iMRI) are currently the most important intraoperative imaging techniques in high grade glioma (HGG) surgery. Few comparative studies exist for these techniques. This review aims to systematically compare 5-ALA and iMRI assisted surgery based on the current literature and discuss the potential impact of a combined use of both techniques.

METHODS

A systematic literature search based on preferred reporting items for systematic reviews and meta-analysis was performed concerning accuracy of tumor detection; extent of resection; neurological deficits (ND); Quality of life (QoL); usability and combined use of both techniques. Original clinical articles on HGG published until March 31st were screened.

RESULTS

169 publications were screened, 81 were eligible and 22 were finally included in the review using. Overall, there is evidence that both imaging techniques improve gross total resection rate in non-eloquent lesions. Imaging results do not correlate at the border zone of a HGG. 5-ALA and contrast-enhanced iMRI seem to have a supplementary effect in tumor detection. Overall, both imaging techniques alone or combined do not seem to increase rate of permanent ND or decrease QoL in HGG surgery when used with intraoperative monitoring/mapping.

CONCLUSION

Based on the currently available literature no superiority of one technique over the other can be found in the most important outcome parameters. Based on the available information a combined use of 5-ALA and iMRI seems very promising to achieve a resection beyond gadolinium-enhancement. However, only low quality of evidence exists for this approach.

Impact of gender on the survival of patients with glioblastoma

Background: Preclinical models have suggested a role for sex hormones in the development of glioblastoma multiforme (GBM). However, the impact of gender on the survival time of patients with GBM has not been fully understood. The objective of the present study was to clarify the association between gender and survival of patients with GBM by analyzing population-based data.Methods: We searched the Surveillance, Epidemiology, and End-Results database who were diagnosed with GBM between 2000 and 2008 and were treated with surgery. Five-year cancer specific survival data were obtained. Kaplan-Meier methods and multivariable Cox regression models were used to analyze long-term survival outcomes and risk factors.Results: A total of 6586 patients were identified; 61.5% were men and 38.5% were women. The 5-year cancer-specific survival (CSS) rates in the male and female groups were 6.8% and 8.3%, respectively (P=0.002 by univariate and P<0.001 by multivariate analysis). A stratified analysis showed that male patients always had the lowest CSS rate across localized cancer stage and different age subgroups.Conclusions: Gender has prognostic value for determining GBM risk. The role of sex hormones in the development of GBM warrants further investigation.

Surgery and Evidence-based Treatments in Patients with Newly Diagnosed High-grade Glioma

OBJECTIVE

To describe the currently accepted standard-of-care practice for surgical and medical management of newly diagnosed high-grade glioma.

DATA SOURCES

Peer-reviewed journals, nationally accepted guidelines, and personal experience of the authors.

CONCLUSION

There is a widely accepted standard-of-care treatment protocol for patients with newly diagnosed high-grade glioma that includes maximal safe resection followed by radiation therapy with concurrent and adjuvant temozolomide. The regimen is well-tolerated and side effects are manageable.

IMPLICATIONS FOR NURSING PRACTICE

Nurses who are involved in the care of patients with newly diagnosed high-grade glioma should be familiar with the regimen and its side effects to provide crucial patient and caregiver education in an accurate and beneficial manner.

In Vivo Real-Time Discrimination Among Glioma, Infiltration Zone, and Normal Brain Tissue via Autofluorescence Technology

BACKGROUND

Surgery is the first-line therapy for glioblastoma. There is evidence that extent of resection is significantly associated with patient survival. Unfortunately, optimal surgical resection is usually limited because of the difficulty in discriminating tumor-infiltrated region and normal brain tissue. This study aimed to develop a tool to distinguish between infiltration zone and normal tissue in real time during glioma surgery.

METHODS

In an in vivo study, C6 glioma cells were implanted into the left cerebral hemispheres of 6 rats to mimic tumorigenesis. A newly designed optical fiber-embedded needle probe was used to measure the autofluorescence of both cerebral hemispheres at various depths 5 days after the implantation. These rats were then sacrificed, and both cerebral hemispheres were removed for histopathologic analysis.

RESULTS

Comparative analyses of corresponding areas by histopathology and autofluorescence revealed highly significant (P < 0.001) differences among the normal tissue, infiltration zone, tumors, and the contralateral cerebral hemispheres. The area of the receiver operating characteristic curve was 0.978, and the sensitivity and specificity of tumor delineation were 93.9% and 94.4%, respectively.

CONCLUSIONS

The newly designed in vivo fiber-optic probe can distinguish tumor-infiltration zones from normal brain tissue in this in vivo study. Therefore, it may help neurosurgeons to increase extent of resection without damaging normal brain tissue and thus potentially improve the patients' survival and quality of life.

Determination of confocal profile and curved focal plane for OCT mapping of the attenuation coefficient

The attenuation coefficient has proven to be a useful tool in numerous biological applications, but accurate calculation is dependent on the characterization of the confocal effect. This study presents a method to precisely determine the confocal effect and its focal plane within a sample by examining the ratio of two optical coherence tomography (OCT) images. The method can be employed to produce a single-value estimate, or a 2D map of the focal plane accounting for the curvature or tilt within the sample. Furthermore, this method is applicable to data obtained with both high numerical aperture (NA) and low-NA lenses, thereby furthering the applicability of the attenuation coefficient to high-NA OCT data. We test and validate this method using standard samples of Intralipid 20% and 5%, improving the accuracy to 99% from 65% compared to the traditional method and preliminarily show applicability to real biological data of glioblastoma acquired in vivo in a murine model.

Spinal cord astrocytomas: progresses in experimental and clinical investigations for developing recovery neurobiology-based novel therapies

Spinal cord astrocytomas (SCAs) have discernibly unique signatures in regards to epidemiology, clinical oncological features, genetic markers, pathophysiology, and research and therapeutic challenges. Overall, there are presently very limited clinical management options for high grade SCAs despite progresses made in validating key molecular markers and standardizing tumor classification. The endeavors were aimed to improve diagnosis, therapy design and prognosis assessment, as well as to define more effective oncolytic targets. Efficacious treatment for high grade SCAs still remains an unmet medical demand. This review is therefore focused on research state updates that have been made upon analyzing clinical characteristics, diagnostic classification, genetic and molecular features, tumor initiation cell biology, and current management options for SCAs. Particular emphasis was given to basic and translational research endeavors targeting SCAs, including establishment of experimental models, exploration of unique profiles of SCA stem cell-like tumor survival cells, characterization of special requirements for effective therapeutic delivery into the spinal cord, and development of donor stem cell-based gene-directed enzyme prodrug therapy. We concluded that precise understanding of molecular oncology, tumor survival mechanisms (e.g., drug resistance, metastasis, and cancer stem cells/tumor survival cells), and principles of Recovery Neurobiology can help to create clinically meaningful experimental models of SCAs. Establishment of such systems will expedite the discovery of efficacious therapies that not only kill tumor cells but simultaneously preserve and improve residual neural function.

Application of an assay Cascade methodology for a deep preclinical characterization of polymeric nanoparticles as a treatment for gliomas

Glioblastoma multiforme (GBM) is the most devastating primary brain tumor due to its infiltrating and diffuse growth characteristics, a situation compounded by the lack of effective treatments. Currently, many efforts are being devoted to find novel formulations to treat this disease, specifically in the nanomedicine field. However, due to the lack of comprehensive characterization that leads to insufficient data on reproducibility, only a reduced number of nanomedicines have reached clinical phases. In this context, the aim of the present study was to use a cascade of assays that evaluate from physical-chemical and structural properties to biological characteristics, both in vitro and in vivo, and also to check the performance of nanoparticles for glioma therapy. An amphiphilic block copolymer, composed of polyester and poly(ethylene glycol; PEG) blocks, has been synthesized. Using a mixture of this copolymer and a polymer containing an active targeting moiety to the Blood Brain Barrier (BBB; Seq12 peptide), biocompatible and biodegradable polymeric nanoparticles have been prepared and extensively characterized. In vitro studies demonstrated that nanoparticles are safe for normal cells but cytotoxic for cancer cells. In vivo studies in mice demonstrated the ability of the Seq12 peptide to cross the BBB. Finally, in vivo efficacy studies using a human tumor model in SCID mice resulted in a significant 50% life-span increase, as compared with non-treated animals. Altogether, this assay cascade provided extensive pre-clinical characterization of our polymeric nanoparticles, now ready for clinical evaluation.

Extending the resection beyond the contrast-enhancement for glioblastoma: feasibility, efficacy, and outcomes

OBJECT

It is becoming well-established that increasing extent of resection with decreasing residual volume is associated with delayed recurrence and prolonged survival for patients with glioblastoma (GBM). These prior studies are based on evaluating the contrast-enhancing (CE) tumour and not the surrounding fluid attenuated inversion recovery (FLAIR) volume. It therefore remains unclear if the resection beyond the CE portion of the tumour if it translates into improved outcomes for patients with GBM.

METHODS

Adult patients who underwent resection of a primary glioblastoma at a tertiary care institution between January 1, 2007 and December 31, 2012 and underwent radiation and temozolomide chemotherapy were retrospectively reviewed. Pre and postoperative MRI images were measured for CE tumour and FLAIR volumes. Multivariate proportional hazards were used to assess associations with both time to recurrence and death. Values with p < 0.05 were considered statistically significant.

RESULTS

245 patients met the inclusion criteria. The median [IQR] preoperative CE and FLAIR tumour volumes were 31.9 [13.9-56.1] cm³ and 78.3 [44.7-115.6] cm³, respectively. Following surgery, the median [IQR] postoperative CE and FLAIR tumour volumes were 1.9 [0-7.1] cm³ and 59.7 [29.7-94.2] cm³, respectively. In multivariate analyses, the postoperative FLAIR volume was not associated with recurrence and/or survival (p > 0.05). However, the postoperative CE tumour volume was significantly associated with both recurrence [HR (95%CI); 1.026 (1.005-1.048), p = 0.01] and survival [HR (95%CI); 1.027 (1.007-1.032), p = 0.001]. The postoperative FLAIR volume was also not associated with recurrence and/or survival among patients who underwent gross total resection of the CE portion of the tumour as well as those who underwent supratotal resection.

CONCLUSIONS

In this study, the volume of CE tumour remaining after resection is more important than FLAIR volume in regards to recurrence and survival for patients with GBM.

Integration of resting state functional MRI into clinical practice - A large single institution experience

Functional magnetic resonance imaging (fMRI) is an important tool for pre-surgical evaluation of eloquent cortex. Classic task-based paradigms require patient participation and individual imaging sequence acquisitions for each functional domain that is being assessed. Resting state fMRI (rs-fMRI), however, enables functional localization without patient participation and can evaluate numerous functional domains with a single imaging session. To date, post-processing of this resting state data has been resource intensive, which limits its widespread application for routine clinical use. Through a novel automated algorithm and advanced imaging IT structure, we report the clinical application and the large-scale integration of rs-fMRI into routine neurosurgical practice. One hundred and ninety one consecutive patients underwent a 3T rs-fMRI, 83 of whom also underwent both motor and language task-based fMRI. Data were processed using a novel, automated, multi-layer perceptron algorithm and integrated into stereotactic navigation using a streamlined IT imaging pipeline. One hundred eighty-five studies were performed for intracranial neoplasm, 14 for refractory epilepsy and 33 for vascular malformations or other neurological disorders. Failure rate of rs-fMRI of 13% was significantly better than that for task-based fMRI (38.5%,) (p <0.001). In conclusion, at Washington University in St. Louis, rs-fMRI has become an integral part of standard imaging for neurosurgical planning. Resting state fMRI can be used in all patients, and due to its lower failure rate than task-based fMRI, it is useful for patients who are unable to cooperate with task-based studies.

Image-guided surgery using near-infrared Turn-ON fluorescent nanoprobes for precise detection of tumor margins

Complete tumor removal during surgery has a great impact on patient survival. To that end, the surgeon should detect the tumor, remove it and validate that there are no residual cancer cells left behind. Residual cells at the incision margin of the tissue removed during surgery are associated with tumor recurrence and poor prognosis for the patient. In order to remove the tumor tissue completely with minimal collateral damage to healthy tissue, there is a need for diagnostic tools that will differentiate between the tumor and its normal surroundings. Methods: We designed, synthesized and characterized three novel polymeric Turn-ON probes that will be activated at the tumor site by cysteine cathepsins that are highly expressed in multiple tumor types. Utilizing orthotopic breast cancer and melanoma models, which spontaneously metastasize to the brain, we studied the kinetics of our polymeric Turn-ON nano-probes. Results: To date, numerous low molecular weight cathepsin-sensitive substrates have been reported, however, most of them suffer from rapid clearance and reduced signal shortly after administration. Here, we show an improved tumor-to-background ratio upon activation of our Turn-ON probes by cathepsins. The signal obtained from the tumor was stable and delineated the tumor boundaries during the whole surgical procedure, enabling accurate resection. Conclusions: Our findings show that the control groups of tumor-bearing mice, which underwent either standard surgery under white light only or under the fluorescence guidance of the commercially-available imaging agents ProSense® 680 or 5-aminolevulinic acid (5-ALA), survived for less time and suffered from tumor recurrence earlier than the group that underwent image-guided surgery (IGS) using our Turn-ON probes. Our "smart" polymeric probes can potentially assist surgeons' decision in real-time during surgery regarding the tumor margins needed to be removed, leading to improved patient outcome.

Which Parameter Is More Important for the Prognosis of New-Onset Adult Glioblastoma: Residual Tumor Volume or Extent of Resection?

BACKGROUND

The extent of resection (EOR) and residual tumor volume (RTV) are 2 pivotal predictors influencing the survival of patients with new-onset adult glioblastoma. Which of these 2 factors is more important remains unclear, however. The present aimed to evaluate and compare the accuracy of EOR and RTV, based on contrast-enhancing (CE) T1-weighted magnetic resonance imaging (MRI) and T2-weighted/fluid-attenuated inversion recovery (F) MRI, as prognostic factors in these patients.

METHODS

In this retrospective study, data were extracted from the databases of 2 hospitals between January 1, 2013, and December 31, 2015. The subjects were divided into 2 groups, the total resection group and the partial resection group. The analysis comprised EOR and RTV. Statistical analysis was performed after controlling for other relevant factors.

RESULTS

We analyzed 292 patients with new-onset glioblastoma who met the inclusion criteria. In the partial resection group, univariate analysis revealed that CE-EOR, CE-RTV, F-EOR, and F-RTV were correlated with progression-free survival (PFS) and overall survival (OS), but multivariate analysis identified no correlation between CE-EOR or F-EOR and PFS or OS. In the total resection group, F-EOR and F-RTV were correlated with PFS and OS in univariate analysis, but F-EOR was not correlated in multivariate analysis.

CONCLUSIONS

Regardless of total or partial CE tumor resection, EOR might not be an independent prognostic factor. In contrast, RTV has the potential to offer greater predictive power for the prognosis of new-onset adult glioblastoma. Further investigations of the correlations of RTV and EOR with survival in patients with new-onset glioblastoma are needed.

Residual enhancing disease after surgery for glioblastoma: evaluation of practice in the United Kingdom

BACKGROUND

A growing body of clinical data highlights the prognostic importance of achieving gross total resection (GTR) in patients with glioblastoma. The aim of this study was to determine nationwide practice and attitudes towards achieving GTR and dealing with residual enhancing disease.

METHODS

The study was in 2 parts: an electronic questionnaire sent to United Kingdom neuro-oncology surgeons to assess surgical practice followed by a 3-month prospective, multicenter observational study of current neurosurgical oncology practice.

RESULTS

Twenty-seven surgeons representing 22 neurosurgical units completed the questionnaire. Prospective data were collected for 113 patients from 15 neurosurgical units. GTR was deemed to be achieved at time of surgery in 82% (91/111) of cases, but in only 45% (36/80) on postoperative MRI. Residual enhancing disease was deemed operable in 16.3% (13/80) of cases, however, no patient underwent early repeat surgery for residual enhancing disease. The most commonly cited reason (38.5%, 5/13) was perceived lack of clinical benefit.

CONCLUSION

There is a subset of patients for whom GTR is thought possible, but not achieved at surgery. For these patients, early repeat resection may improve overall survival. Further prospective surgical research is required to better define the prognostic implications of GTR for residual enhancing disease and examine the potential benefit of this early re-intervention.

The Impact of Intracranial Tumor Proximity to White Matter Tracts on Morbidity and Mortality: A Retrospective Diffusion Tensor Imaging Study

Background

Using diffusion tensor imaging (DTI) in neurosurgical planning allows identification of white matter tracts and has been associated with a reduction in postoperative functional deficits.

Objective

This study explores the relationship between the lesion-to-tract distance (LTD) and postoperative morbidity and mortality in patients with brain tumors in order to evaluate the role of DTI in predicting postoperative outcomes.

Methods

Adult patients with brain tumors (n = 60) underwent preoperative DTI. Three major white matter pathways (superior longitudinal fasciculi [SLF], cingulum, and corticospinal tract) were identified using DTI images, and the shortest LTD was measured for each tract. Postoperative morbidity and mortality information was collected from electronic medical records.

Results

The ipsilesional corticospinal tract LTD and left SLF LTD were significantly associated with the occurrence rate of total postoperative motor (P = .018) and language (P < .001) deficits, respectively. The left SLF LTD was also significantly associated with the occurrence rate of new postoperative language deficits (P = .003), and the LTD threshold that best predicted this occurrence was 1 cm (P < .001). Kaplan–Meier log-rank survival analyses in patients having high-grade tumors demonstrated a significantly higher mortality for patients with a left SLF LTD <1 cm (P = .01).

Conclusion

Measuring tumor proximity to major white matter tracts using DTI can inform clinicians of the likelihood of postoperative functional deficits. A distance of 1 cm or less from eloquent white matter structures most significantly predicts the occurrence of new deficits with current surgical and imaging techniques.

Surgical Considerations in the Optimal Management of Patients with Malignant Brain Tumors

OPINION STATEMENT

Advances in technology are revolutionizing medicine and the limits of what we can offer to our patients. In neurosurgery, technology continues to reduce morbidity, increase surgical accuracy, facilitate tissue acquisition, and promote novel techniques for prolonging survival in patients with neuro-oncologic disease. Surgery has been the backbone of glioma diagnosis and treatment by providing adequate, high quality material for precise histologic diagnosis, and genomic characterization in the setting of significant intratumoral heterogeneity, thus allowing personalized treatment selection in the clinic. The ability to obtain and accurately measure the maximal extent of resection in glioma surgery also remains a central role of the neurosurgeon in managing this cancer. To meet these goals, today's operating room has transformed from the traditional operating table and anesthesia machine to include neuronavigation instrumentation, intraoperative computed tomography, and magnetic resonance imaging scanners, advanced surgical microscopes fitted with fluorescent light filters, and electrocorticography machines. While surgeons, oncologists, and radiation oncologists all play unique critical roles in the care of patients with malignant gliomas, familiarity with developing techniques in complimentary subspecialties can enhance coordination of patient care, research productivity, professional interactions, and patient confidence and comfort with the physician team. Herein, we provide a summary of the advances in the field of neurosurgical oncology which allow more precise and optimal surgical resection for patients with malignant gliomas.

In Vivo Microscopy in Neurosurgical Oncology

Intraoperative neurosurgical histopathologic diagnoses rely on evaluation of rapid tissue preparations such as frozen sections and smears with conventional light microscopy. Although useful, these techniques are time consuming and therefore cannot provide real-time intraoperative feedback. In vivo molecular imaging techniques are emerging as novel methods for generating real-time diagnostic histopathologic images of tumors and their surrounding tissues. These imaging techniques rely on contrast generated by exogenous fluorescent dyes, autofluorescence of endogenous molecules, fluorescence decay of excited molecules, or light scattering. Large molecular imaging instruments are being miniaturized for clinical in vivo use. This review discusses pertinent imaging systems that have been developed for neurosurgical use and imaging techniques currently under development for neurosurgical molecular imaging.

Reoperation for Recurrent Glioblastoma Multiforme

The role of reoperation for glioblastoma multiforme (GBM) recurrence is currently unknown. However, multiple studies have indicated that survival and quality of life are improved with a repeat operation at the time of disease recurrence. Prognosis is likely interdependent on several factors, including age, functional status, initial resection status, disease location, and surgical efficacy. However, there are significant data indicating no survival benefit for reoperation. This comprehensive literature review considering the controversial question of whether to operate for progressive or recurrent GBM seeks to evaluate the current available evidence and report on its conclusions.

Infarct volume after glioblastoma surgery as an independent prognostic factor

Postoperative ischemia is associated with reduced functional independence measured by karnofsky performance score (KPS), which correlates well with overall survival. Other studies suggest that postoperative hypoxia might initiate infiltrative tumor growth. Therefore, aim of this study was to analyze the impact of infarct volume on overall survival and progression free survival (PFS) of glioblastoma patients.

251 patients with surgery for a newly diagnosed glioblastoma (WHO IV) were retrospectively assessed. Pre- and postoperative KPS, date of death/last follow-up and histopathological markers were recorded. Pre- and postoperative tumor volume and the volume of postoperative infarction were manually segmented.

A significant correlation of infarct volume with postoperative KPS decrease (P = 0.001) was observed. Infarct volume showed a significant impact on overall survival (P = 0.014), but not on PFS (P = 0.112) in univariate analysis. This effect increased in the subgroup of patients with near-total tumor resection (> 90%) (overall survival: P = 0.006, PFS: P = 0.066). Infarct volume remained as an independent prognostic factor for overall survival in multivariate analysis (HR 1.013 [1.000–1.026], P = 0.042) including other prognostic factors (age, extent of resection, postoperative KPS).

Postoperative infarct volume significantly correlates as an independent factor with overall survival after glioblastoma surgery. Besides the influence of perioperative infarction on postoperative KPS, postoperative hypoxia might also have an effect on tumor biology initiating infiltrative growth and therefore impaired survival.

Awake Craniotomy vs Craniotomy Under General Anesthesia for Perirolandic Gliomas: Evaluating Perioperative Complications and Extent of Resection

BACKGROUND

A craniotomy with direct cortical/subcortical stimulation either awake or under general anesthesia (GA) present 2 approaches for removing eloquent region tumors. With a reported higher prevalence of intraoperative seizures occurring during awake resections of perirolandic lesions, oftentimes, surgery under GA is chosen for these lesions.

OBJECTIVE

To evaluate a single-surgeon's experience with awake craniotomies (AC) vs surgery under GA for resecting perirolandic, eloquent, motor-region gliomas.

METHODS

Between 2005 and 2015, a retrospective analysis of 27 patients with perirolandic, eloquent, motor-area gliomas that underwent an AC were case-control matched with 31 patients who underwent surgery under GA for gliomas in the same location. All patients underwent direct brain stimulation with neuromonitoring and perioperative risk factors, extent of resection, complications, and discharge status were assessed.

RESULTS

The postoperative Karnofsky Performance Score (KPS) was significantly lower for the GA patients at 81.1 compared to the AC patients at 93.3 ( P = .040). The extent of resection for GA patients was 79.6% while the AC patients had an 86.3% resection ( P = .136). There were significantly more 100% total resections in the AC patients 25.9% compared to the GA group (6.5%; P = .041). Patients in the GA group had a longer mean length of hospitalization of 7.9 days compared to the AC group at 4.2 days ( P = .049).

CONCLUSION

We show that AC can be performed with more frequent total resections, better postoperative KPS, shorter hospitalizations, as well as similar perioperative complication rates compared to surgery under GA for perirolandic, eloquent motor-region glioma.

The Survival Advantage of "Supratotal" Resection of Glioblastoma Using Selective Cortical Mapping and the Subpial Technique

BACKGROUND

A substantial body of evidence suggests that cytoreductive surgery is a prerequisite to prolonging survival in patients with glioblastoma (GBM).

OBJECTIVE

To evaluate the safety and impact of "supratotal" resections beyond the zone of enhancement seen on magnetic resonance imaging scans, using a subpial technique.

METHODS

We retrospectively evaluated 86 consecutive patients with primary GBM, managed by the senior author, using a subpial resection technique with or without carmustine (BCNU) wafer implantation. Multivariate Cox proportional hazards regression was used to analyze clinical, radiological, and outcome variables. Overall impacts of extent of resection (EOR) and BCNU wafer placement were compared using Kaplan-Meier survival analysis.

RESULTS

Mean patient age was 56 years. The median OS for the group was 18.1 months. Median OS for patients undergoing gross total, near-total, and subtotal resection were 54, 16.5, and 13.2 months, respectively. Patients undergoing near-total resection ( P = .05) or gross total resection ( P < .01) experienced statistically significant longer survival time than patients undergoing subtotal resection as well as patients undergoing ≥95% EOR ( P < .01) when compared to <95% EOR. The addition of BCNU wafers had no survival advantage.

CONCLUSIONS

The subpial technique extends the resection beyond the contrast enhancement and is associated with an overall survival beyond that seen in similar series where resection of the enhancement portion is performed. The effect of supratotal resection on survival exceeded the effects of age, Karnofsky performance score, and tumor volume. A prospective study would help to quantify the impact of the subpial technique on quality of life and survival as compared to a traditional resection limited to the enhancing tumor.

Retrospective Analysis of Radiological Recurrence Patterns in Glioblastoma, Their Prognostic Value And Association to Postoperative Infarct Volume

Recent studies suggested that postoperative hypoxia might trigger invasive tumor growth, resulting in diffuse/multifocal recurrence patterns. Aim of this study was to analyze distinct recurrence patterns and their association to postoperative infarct volume and outcome. 526 consecutive glioblastoma patients were analyzed, of which 129 met our inclusion criteria: initial tumor diagnosis, surgery, postoperative diffusion-weighted imaging and tumor recurrence during follow-up. Distinct patterns of contrast-enhancement at initial diagnosis and at first tumor recurrence (multifocal growth/progression, contact to dura/ventricle, ependymal spread, local/distant recurrence) were recorded by two blinded neuroradiologists. The association of radiological patterns to survival and postoperative infarct volume was analyzed by uni-/multivariate survival analyses and binary logistic regression analysis. With increasing postoperative infarct volume, patients were significantly more likely to develop multifocal recurrence, recurrence with contact to ventricle and contact to dura. Patients with multifocal recurrence (Hazard Ratio (HR) 1.99, P = 0.010) had significantly shorter OS, patients with recurrent tumor with contact to ventricle (HR 1.85, P = 0.036), ependymal spread (HR 2.97, P = 0.004) and distant recurrence (HR 1.75, P = 0.019) significantly shorter post-progression survival in multivariate analyses including well-established prognostic factors like age, Karnofsky Performance Score (KPS), therapy, extent of resection and patterns of primary tumors. Postoperative infarct volume might initiate hypoxia-mediated aggressive tumor growth resulting in multifocal and diffuse recurrence patterns and impaired survival.

Impact of Laterality on Surgical Outcome of Glioblastoma Patients: A Retrospective Single-Center Study

BACKGROUND

Resection of left hemisphere (LH) tumors is often complicated by the risks of causing language dysfunction. Although neurosurgeons' concerns when operating on the presumed dominant hemisphere are well known, literature evaluating laterality as a predictive surgical parameter in glioblastoma (GB) patients is sparse. We evaluated whether tumor laterality correlated with surgical performance, functional outcome, and survival.

METHODS

All patients with GB treated at our institution between 2006 and 2016 were reviewed. Analysis comprised clinical characteristics, extent of resection (EOR), neurologic outcome, and survival in relation to tumor lateralization.

RESULTS

Two hundred thirty-five patients were included. Right hemisphere (RH) tumors were larger and more frequently extended into the frontal lobe. Preoperatively, limb paresis was more frequent in RH, whereas language deficits were more frequent in LH tumors (P = 0.0009 and P < 0.0001, respectively). At 6 months after resection, LH patients presented lower Karnofsky Performance Status (KPS) score (P = 0.036). More patients with LH tumors experienced dysphasia (P < 0.0001), and no difference was seen for paresis. Average EOR was comparable, but complete resection was achieved less often in LH tumors (37.7 vs. 64.8%; P = 0.0028). Although overall survival did not differ between groups, progression-free survival was shorter in LH tumors (7.4 vs. 10.1 months; P = 0.0225).

CONCLUSIONS

Patients with LH tumors had a pronounced KPS score decline and shorter progression-free survival without effects on overall survival. This observation might partially be attributed to a more conservative surgical resection. Further investigation is needed to assess whether systematic use of awake surgery and intraoperative mapping results in increased EOR and improved quality survival of patients with GB.

Practical prognostic score for predicting the extent of resection and neurological outcome of gliomas in the sensorimotor area

OBJECTIVE

In this prospective study, we assessed the utility of a novel prognostic score (PS) in guiding the surgical strategy of patients with sensorimotor area gliomas.

PATIENTS AND METHODS

Form December 2012 to April 2016, we collected data from patients diagnosed with brain gliomas in the sensorimotor area. All the patients had intraoperatively confirmed contiguity or continuity with sensorimotor cortical and subcortical structures. Several clinical and radiological factors were analyzed to generate a PS for each patient (range 1-8). The end-points included the extent of resection (EOR) and neurological outcome (modified Rankin Score; mRS). We assessed the predictive power of the PS using different analyses. Crosstabs analyses and Fisher's exact test (Fet) were used to evaluate the possible predictive parameters, and for the classification of positive or negative outcomes for the chosen proxies; the significance threshold was set at p<0.05.

RESULTS

Using independent t-tests, we compared the mRS at different time points (pre, post, and at 6 months) for 2 subgroups from the total sample using a cut-off PS value of 4. For the EOR, a PS value of ≥5 was predictive of successful outcome, a value of 4 indicated an uncertain outcome, and a value of ≤3 predicted a worse outcome.

CONCLUSIONS

This PS value can be easily used in clinical settings to help predict the functional outcome and EOR in sensorimotor area tumors. Integration with information from fMRI, DTI, and TMS, along with MRI spectroscopy could further enhance the value of this PS.

Specific DTI seeding and diffusivity-analysis improve the quality and prognostic value of TMS-based deterministic DTI of the pyramidal tract

Object

Navigated transcranial magnetic stimulation (nTMS) combined with diffusion tensor imaging (DTI) is used preoperatively in patients with eloquent-located brain lesions and allows analyzing non-invasively the spatial relationship between the tumor and functional areas (e.g. the motor cortex and the corticospinal tract [CST]). In this study, we examined the diffusion parameters FA (fractional anisotropy) and ADC (apparent diffusion coefficient) within the CST in different locations and analyzed their interrater reliability and usefulness for predicting the patients' motor outcome with a precise approach of specific region of interest (ROI) seeding based on the color-coded FA-map.

Methods

Prospectively collected data of 30 patients undergoing bihemispheric nTMS mapping followed by nTMS-based DTI fiber tracking prior to surgery of motor eloquent high-grade gliomas were analyzed by 2 experienced and 1 unexperienced examiner. The following data were scrutinized for both hemispheres after tractography based on nTMS-motor positive cortical seeds and a 2nd region of interest in one layer of the caudal pons defined by the color-coded FA-map: the pre- and postoperative motor status (day of discharge und 3 months), the closest distance between the tracts and the tumor (TTD), the fractional anisotropy (FA) and the apparent diffusion coefficient (ADC). The latter as an average within the CST as well as specific values in different locations (peritumoral, mesencephal, pontine).

Results

Lower average FA-values within the affected CST as well as higher average ADC-values are significantly associated with deteriorated postoperative motor function (p = 0.006 and p = 0.026 respectively). Segmental analysis within the CST revealed that the diffusion parameters are especially disturbed on a peritumoral level and that the degree of their impairment correlates with motor deficits (FA p = 0.065, ADC p = 0.007). No significant segmental variation was seen in the healthy hemisphere. The interrater reliability showed perfect agreement for almost all analyzed parameters.

Conclusions

Adding diffusion weighted imaging derived information on the structural integrity of the nTMS-based tractography results improves the predictive power for postoperative motor outcome. Utilizing a second subcortical ROI which is specifically seeded based on the color-coded FA map increases the tracking quality of the CST independently of the examiner's experience. Further prospective studies are needed to validate the nTMS-based prediction of the patient's outcome.

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ROI seeding based on nTMS-data and FA-maps improves DTI tractography of the CST.

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Perfect interrater reliability for DTI tractography of the CST was observed.

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The pattern of diffusivity disturbance predicts the postoperative motor outcome.

Safe Brain Tumor Resection Does not Depend on Surgery Alone - Role of Hemodynamics

Aim of this study was to determine if perioperative hemodynamics have an impact on perioperative infarct volume and patients’ prognosis. 201 cases with surgery for a newly diagnosed or recurrent glioblastoma were retrospectively analyzed. Clinical data and perioperative hemodynamic parameters, blood tests and time of surgery were recorded. Postoperative infarct volume was quantitatively assessed by semiautomatic segmentation. Mean diastolic blood pressure (dBP) during surgery (rho −0.239, 95% CI −0.11 – −0.367, p = 0.017), liquid balance (rho 0.236, 95% CI 0.1–0.373, p = 0.017) and mean arterial pressure (MAP) during surgery (rho −0.206, 95% CI −0.07 – −0.34, p = 0.041) showed significant correlation to infarct volume. A rank regression model including also age and recurrent surgery as possible confounders revealed mean intraoperative dBP, liquid balance and length of surgery as independent factors for infarct volume. Univariate survival analysis showed mean intraoperative dBP and MAP as significant prognostic factors, length of surgery also remained as significant prognostic factor in a multivariate model. Perioperative close anesthesiologic monitoring of blood pressure and liquid balance is of high significance during brain tumor surgery and should be performed to prevent or minimize perioperative infarctions and to prolong survival.

Impact of removed tumor volume and location on patient outcome in glioblastoma

Glioblastoma is an aggressive primary brain tumor with devastatingly poor prognosis. Multiple studies have shown the benefit of wider extent of resection (EOR) on patient overall survival (OS) and worsened survival with larger preoperative tumor volumes. However, the concomitant impact of postoperative tumor volume and eloquent location on OS has yet to be fully evaluated. We performed a retrospective chart review of adult patients treated for glioblastoma from January 2006 through December 2011. Adherence to standardized postoperative chemoradiation protocols was used as an inclusion criterion. Detailed volumetric and location analysis was performed on immediate preoperative and immediate postoperative magnetic resonance imaging. Cox proportional hazard modeling approach was employed to explore the modifying effects of EOR and eloquent location after adjusting for various confounders and associated characteristics, such as preoperative tumor volume and demographics. Of the 471 screened patients, 141 were excluded because they did not meet all inclusion criteria. The mean (±SD) age of the remaining 330 patients (60.6% male) was 58.9 ± 12.9 years; the mean preoperative and postoperative Karnofsky performance scores (KPSs) were 76.2 ± 10.3 and 80.0 ± 16.6, respectively. Preoperative tumor volume averaged 33.2 ± 29.0 ml, postoperative residual was 4.0 ± 8.1 ml, and average EOR was 88.6 ± 17.6%. The observed average follow-up was 17.6 ± 15.7 months, and mean OS was 16.7 ± 14.4 months. Survival analysis showed significantly shorter survival for patients with lesions in periventricular (16.8 ± 1.7 vs. 21.5 ± 1.4 mo, p = 0.03), deep nuclei/basal ganglia (11.6 ± 1.7 vs. 20.6 ± 1.2, p = 0.002), and multifocal (12.0 ± 1.4 vs. 21.3 ± 1.3 months, p = 0.0001) locations, but no significant influence on survival was seen for eloquent cortex sites (p = 0.14, range 0.07-0.9 for all individual locations). OS significantly improved with EOR in univariate analysis, averaging 22.3, 19.7, and 13.2 months for >90, 80-90, and 70-80% resection, respectively. Survival was 22.8, 19.0, and 12.7 months for 0, 0-5, and 5-10 ml postoperative residual, respectively. A hazard model showed that larger preoperative tumor volume [hazard ratio (HR) 1.05, 95% CI 1.02-1.07], greater age (HR 1.02, 95% CI 1.01-1.03), multifocality (HR 1.44, 95% CI 1.01-2.04), and deep nuclei/basal ganglia (HR 2.05, CI 1.27-3.3) were the most predictive of poor survival after adjusting for KPS and tumor location. There was a negligible but significant interaction between EOR and preoperative tumor volume (HR 0.9995, 95% CI 0.9993-0.9998), but EOR alone did not correlate with OS after adjusting for other factors. The interaction between EOR and preoperative tumor volume represented tumor volume removed during surgery. In conclusion, EOR alone was not an important predictor of outcome during GBM treatment once preoperative tumor volume, age, and deep nuclei/basal ganglia location were factored. Instead, the interaction between EOR and preoperative volume, representing reduced disease burden, was an important predictor of reducing OS. Removal of tumor from eloquent cortex did not impact postoperative KPS. These results suggest aggressive surgical treatment to reduce postoperative residual while maintaining postoperative KPS may aid patient survival outcomes for a given tumor size and location.

Combining Functional Studies with Intraoperative MRI in Glioma Surgery

Maximal safe resection is the cornerstone of treatment for low-grade and high-grade gliomas. In addition to high-resolution anatomic MRI studies that highlight tumor architecture, it is important to determine the relationship of the tumor to the eloquent cortical and subcortical areas to avoid introducing or exacerbating a neurologic deficit. The goal of this review was to highlight imaging modalities that provide functional information and can be integrated with intraoperative MRI navigation to maximize the extent of resection while preserving a patient's neurologic function.

Brain Arteriovenous Malformations Located in Language Area: Surgical Outcomes and Risk Factors for Postoperative Language Deficits

OBJECTIVE

Case selection for surgical treatment of language-area brain arteriovenous malformations (L-BAVMs) remains difficult. This study aimed to determine the surgical outcomes and risk factors for postoperative language deficits (LDs) in patients with L-BAVMs.

METHODS

Patients with L-BAVMs who underwent microsurgical resection between September 2012 and June 2016 were reviewed. All patients had undergone preoperative functional magnetic resonance imaging and diffusion tensor imaging. Both functional and angioarchitectural factors were analyzed regarding the postoperative LD. Functional factors included the eloquence involved, the side of blood-oxygenation level-dependent signal activation and the white-matter fibers (anterior segment, long segment [LS], and posterior segment of arcuate fasciculus, and the inferior fronto-occipital fasciculus) involved.

RESULTS

Sixty-nine patients with L-BAVMs were reviewed. Postoperative short- and long-term LD was found in 32 (46.4%) and 14 (20.3%) patients, respectively. Twelve of the 14 patients with Geschwind's territory L-BAVMs (85.7%) had short-term LD, compared with 10 (34.5%) in Wernicke's and 10 (38.5%) in Broca's area. LS involvement (P = 0.001) and larger nidus size (P = 0.017) were independent risk factors for the short-term LD. Meanwhile, nidus size (P = 0.007), preoperative LD (P = 0.008), and LS involvement (P = 0.028) were independent risk factors for long-term LD.

CONCLUSIONS

L-BAVMs located in Geschwind's territory can cause a high incidence of LD. LS involvement and larger nidus size are risk factors for postoperative short- and long-term LD, and preoperative LD is a risk factor for postoperative, long-term LD.

Patients' perspective on awake craniotomy for brain tumors-single center experience in Brazil

BACKGROUND

Awake craniotomy with brain mapping is the gold standard for eloquent tissue localization. Patients' tolerability and satisfaction have been shown to be high; however, it is a matter of debate whether these findings could be generalized, since patients across the globe have their own cultural backgrounds and may perceive and accept this procedure differently.

METHODS

We conducted a prospective qualitative study about the perception and tolerability of awake craniotomy in a population of consecutive brain tumor patients in Brazil between January 2013 and April 2015. Seventeen patients were interviewed using a semi-structured model with open-ended questions.

RESULTS

Patients' thoughts were grouped into five categories: (1) overall perception: no patient considered awake craniotomy a bad experience, and most understood the rationale behind it. They were positively surprised with the surgery; (2) memory: varied from nothing to the entire surgery; (3) negative sensations: in general, it was painless and comfortable. Remarks concerning discomfort on the operating table were made; (4) postoperative recovery: perception of the postoperative period was positive; (5) previous surgical experiences versus awake craniotomy: patients often preferred awake surgery over other surgery under general anesthesia, including craniotomies.

CONCLUSIONS

Awake craniotomy for brain tumors was well tolerated and yielded high levels of satisfaction in a population of patients in Brazil. This technique should not be avoided under the pretext of compromising patients' well-being.

Associations between clinical outcome and navigated transcranial magnetic stimulation characteristics in patients with motor-eloquent brain lesions: a combined navigated transcranial magnetic stimulation-diffusion tensor imaging fiber tracking approach

OBJECTIVE Navigated transcranial magnetic stimulation (nTMS) and diffusion tensor imaging fiber tracking (DTI FT) based on nTMS data are increasingly used for preoperative planning and resection guidance in patients suffering from motor-eloquent brain tumors. The present study explores whether nTMS-based DTI FT can also be used for individual preoperative risk assessment regarding surgery-related motor impairment. METHODS Data derived from preoperative nTMS motor mapping and subsequent nTMS-based tractography in 86 patients were analyzed. All patients suffered from high-grade glioma (HGG), low-grade glioma (LGG), or intracranial metastasis (MET). In this context, nTMS-based DTI FT of the corticospinal tract (CST) was performed at a range of fractional anisotropy (FA) levels based on an individualized FA threshold ([FAT]; tracking with 50%, 75%, and 100% FAT), which was defined as the highest FA value allowing for visualization of fibers (100% FAT). Minimum lesion-to-CST distances were measured, and fiber numbers of the reconstructed CST were assessed. These data were then correlated with the preoperative, postoperative, and follow-up status of motor function and the resting motor threshold (rMT). RESULTS At certain FA levels, a statistically significant difference in lesion-to-CST distances was observed between patients with HGG who had no impairment and those who developed surgery-related transient or permanent motor deficits (75% FAT: p = 0.0149; 100% FAT: p = 0.0233). In this context, no patient with a lesion-to-CST distance ≥ 12 mm suffered from any new surgery-related permanent paresis (50% FAT and 75% FAT). Furthermore, comparatively strong negative correlations were observed between the rMT and lesion-to-CST distances of patients with surgery-related transient paresis (Spearman correlation coefficient [r_s]; 50% FAT: r_s = -0.8660; 75% FAT: r_s = -0.8660) or surgery-related permanent paresis (50% FAT: r_s = -0.7656; 75% FAT: r_s = -0.6763). CONCLUSIONS This is one of the first studies to show a direct correlation between imaging, clinical status, and neurophysiological markers for the integrity of the motor system in patients with brain tumors. The findings suggest that nTMS-based DTI FT might be suitable for individual risk assessment in patients with HGG, in addition to being a surgery-planning tool. Importantly, necessary data for risk assessment were obtained without significant additional efforts, making this approach potentially valuable for direct clinical use.

A Single-Center Cost Analysis of Treating Primary and Metastatic Brain Cancers with Either Brain Laser Interstitial Thermal Therapy (LITT) or Craniotomy

BACKGROUND

Brain laser interstitial thermal therapy (LITT) under magnetic resonance imaging (MRI) guidance has recently gained US clinical approval for the ablation of soft, neurological tissue. LITT is a minimally invasive alternative to craniotomy.

OBJECTIVE

While safety and efficacy are the focus of most current LITT studies, it is unclear how acute care costs (inpatient care ± aftercare) of LITT compare to craniotomy in an academic medical center. Therefore, the purpose of this analysis is to examine these costs of using brain LITT under MRI guidance compared to craniotomy in complex anatomies.

METHODS

Consecutive patients treated at a single US center from 1 January 2010 to 21 October 2014 were retrospectively evaluated. Patients were included if they had a primary procedure for LITT or craniotomy (International Classification of Diseases, 9th revision, Clinical Modification [ICD-9-CM] procedure code 17.61 or ICD-9-CM procedure code 01.59, respectively) and were subgrouped according to their diagnosis of primary brain or metastatic brain cancer (ICD-9-CM 191.0-191.9 or ICD-9-CM 198.3, respectively). Patients were excluded if they had co-morbid conditions such as brain edema (ICD-9-CM 348.5). Patients were matched (LITT vs. craniotomy) based on diagnosis. Appropriate statistical analyses were undertaken to examine the year 2015 costs for care in all settings (acute hospital and post-hospital care, i.e., skilled nursing facility, rehabilitation, and home care) were examined.

RESULTS

In patients treated for a primary brain cancer, there was no statistical difference in the acute and post-care costs of LITT and craniotomy (inverse variance, mean difference [MD], random effects model): MD = -US$1669; 95% confidence interval (CI) -$8192 to $4854; P = 0.62. When examining difficult to access primary malignancies, no difference was found: MD = -US$4719; 95% CI -$12,183 to $2745; P = 0.22. In metastatic brain cancer, LITT was found to be significantly less costly than craniotomy: MD = -US$6522; 95% CI -$11,911 to -$1133; P = 0.02.

CONCLUSIONS

In patients with metastatic brain cancer, LITT is less costly than craniotomy. Patients receiving LITT had a significantly shorter length of hospital stay, were significantly older, and were more likely to be discharged home. The use of LITT may be a reasonable option in bundled episodes of care for brain cancer and may fit into the Bundled Payment for Care Improvement (BPCI) program being evaluated by Medicare and providers.

Results of a multicenter survey showing interindividual variability among neurosurgeons when deciding on the radicality of surgical resection in glioblastoma highlight the need for more objective guidelines

PURPOSE

We assessed agreement among neurosurgeons on surgical approaches to individual glioblastoma patients and between their approach and those recommended by the topographical staging system described by Shinoda.

METHODS

Five neurosurgeons were provided with pre-surgical MRIs of 76 patients. They selected the surgical approach [biopsy, partial resection, or gross total resection (GTR)] that they would recommend for each patient. They were blinded to each other's response and they were told that patients were younger than 50 years old and without symptoms. Three neuroradiologists classified each case according to the Shinoda staging system.

RESULTS

Biopsy was recommended in 35.5-82.9%, partial resection in 6.6-32.9%, and GTR in 3.9-31.6% of cases. Agreement among their responses was fair (global kappa = 0.28). Nineteen patients were classified as stage I, 14 as stage II, and 43 as stage III. Agreement between the neurosurgeons and the recommendations of the staging system was poor for stage I (kappa = 0.14) and stage II (kappa = 0.02) and fair for stage III patients (kappa = 0.29). An individual analysis revealed that in contrast to the Shinoda system, neurosurgeons took into account T2/FLAIR sequences and gave greater weight to the involvement of eloquent areas.

CONCLUSIONS

The surgical approach to glioblastoma is highly variable. A staging system could be used to examine the impact of extent of resection, monitor post-operative complications, and stratify patients in clinical trials. Our findings suggest that the Shinoda staging system could be improved by including T2/FLAIR sequences and a more adequate weighting of eloquent areas.

Complications of ventricular entry during craniotomy for brain tumor resection

OBJECTIVE Recent studies have demonstrated that periventricular tumor location is associated with poorer survival and that tumor location near the ventricle limits the extent of resection. This finding may relate to the perception that ventricular entry leads to further complications and thus surgeons may choose to perform less aggressive resection in these areas. However, there is little support for this view in the literature. This study seeks to determine whether ventricular entry is associated with more complications during craniotomy for brain tumor resection. METHODS A retrospective analysis of patients who underwent craniotomy for tumor resection at Henry Ford Hospital between January 2010 and November 2012 was conducted. A total of 183 cases were reviewed with attention to operative entry into the ventricular system, postoperative use of an external ventricular drain (EVD), subdural hematoma, hydrocephalus, and symptomatic intraventricular hemorrhage (IVH). RESULTS Patients in whom the ventricles were entered had significantly higher rates of any complication (46% vs 21%). Complications included development of subdural hygroma, subdural hematoma, intraventricular hemorrhage, subgaleal collection, wound infection, urinary tract infection/deep venous thrombosis, hydrocephalus, and ventriculoperitoneal (VP) shunt placement. Specifically, these patients had significantly higher rates of EVD placement (23% vs 1%, p < 0.001), hydrocephalus (6% vs 0%, p = 0.03), IVH (14% vs 0%, p < 0.001), infection (15% vs 5%, p = 0.04), and subgaleal collection (20% vs 4%, p < 0.001). It was also observed that VP shunt placement was only seen in cases of ventricular entry (11% vs 0%, p = 0.001) with 3 of 4 of these patients having a large ventricular entry (defined here as entry greater than a pinhole [< 3 mm] entry). Furthermore, in a subset of glioblastoma patients with and without ventricular entry, Kaplan-Meier estimates for survival demonstrated a median survival time of 329 days for ventricular entry compared with 522 days for patients with no ventricular entry (HR 1.13, 95% CI 0.65-1.96; p = 0.67). CONCLUSIONS There are more complications associated with ventricular entry during brain tumor resection than in nonviolated ventricular systems. Better strategies for management of periventricular tumor resection should be actively sought to improve resection and survival for these patients.

Laser interstitial thermal therapy for newly diagnosed and recurrent glioblastoma

OBJECTIVE

Glioblastoma (GBM) is the most common and deadly malignant primary brain tumor. Better surgical therapies are needed for newly diagnosed GBMs that are difficult to resect and for GBMs that recur despite standard therapies. The authors reviewed their institutional experience of using laser interstitial thermal therapy (LITT) for the treatment of newly diagnosed or recurrent GBMs.

METHODS

This study reports on the pre-LITT characteristics and post-LITT outcomes of 8 patients with newly diagnosed GBMs and 13 patients with recurrent GBM who underwent LITT.

RESULTS

Compared with the group with recurrent GBMs, the patients with newly diagnosed GBMs who underwent LITT tended to be older (60.8 vs 48.9 years), harbored larger tumors (22.4 vs 14.6 cm3), and a greater proportion had IDH wild-type GBMs. In the newly diagnosed GBM group, the median progression-free survival and the median survival after the procedure were 2 months and 8 months, respectively, and no patient demonstrated radiographic shrinkage of the tumor on follow-up imaging. In the 13 patients with recurrent GBM, 5 demonstrated a response to LITT, with radiographic shrinkage of the tumor following ablation. The median progression-free survival was 5 months, and the median survival was greater than 7 months.

CONCLUSIONS

In carefully selected patients with recurrent GBM, LITT may be an effective alternative to surgery as a salvage treatment. Its role in the treatment of newly diagnosed unresectable GBMs is not established yet and requires further study.

The effects of new or worsened postoperative neurological deficits on survival of patients with glioblastoma

OBJECTIVE An increased extent of resection (EOR) has been shown to improve overall survival of patients with glioblastoma (GBM) but has the potential for causing a new postoperative neurological deficit. To investigate the impact of surgical neurological morbidity on survival, the authors performed a retrospective analysis of the clinical data from patients with GBM to quantify the impact of a new neurological deficit on the survival benefit achieved with an increased EOR. METHODS The data from all GBM patients who underwent resection at the University of Florida from 2010 to 2015 with postoperative imaging within 72 hours of surgery were included in the study. Retrospective analysis was performed on clinical outcomes and tumor volumes determined on postoperative and follow-up imaging examinations. RESULTS Overall, 115 patients met the inclusion criteria for the study. Tumor volume at the time of presentation was a median of 59 cm³ (enhanced on T1-weighted MRI scans). The mean EOR (± SD) was 94.2% ± 8.7% (range 59.9%-100%). Almost 30% of patients had a new postoperative neurological deficit, including motor weakness, sensory deficits, language difficulty, visual deficits, confusion, and ataxia. The neurological deficits had resolved in 41% of these patients on subsequent follow-up examinations. The median overall survival was 13.1 months (95% CI 10.9-15.2 months). Using a multipredictor Cox model, the authors observed that increased EOR was associated with improved survival except for patients with smaller tumor volumes (≤ 15 cm³). A residual volume of 2.5 cm³ or less predicted a favorable overall survival. Developing a postoperative neurological deficit significantly affected survival (9.2 months compared with 14.7 months, p = 0.02), even if the neurological deficit had resolved by the first follow-up. However, there was a trend of improved survival among patients with resolution of a neurological deficit by the first follow-up compared with patients with a permanent neurological deficit. Any survival benefit from achieving a 95% EOR was abrogated by the development of a new neurological deficit postoperatively. CONCLUSIONS Developing a new neurological deficit after resection of GBM is associated with a decrease in overall survival. A careful balance between EOR and neurological compromise needs to be taken into account to reduce the likelihood of neurological morbidity from surgery.

Functional connectivity networks for preoperative brain mapping in neurosurgery

OBJECTIVE Resection of focal brain lesions involves maximizing the resection while preserving brain function. Mapping brain function has entered a new era focusing on distributed connectivity networks at "rest," that is, in the absence of a specific task or stimulus, requiring minimal participant engagement. Central to this frame shift has been the development of methods for the rapid assessment of whole-brain connectivity with functional MRI (fMRI) involving blood oxygenation level-dependent imaging. The authors appraised the feasibility of fMRI-based mapping of a repertoire of functional connectivity networks in neurosurgical patients with focal lesions and the potential benefits of resting-state connectivity mapping for surgical planning. METHODS Resting-state fMRI sequences with a 3-T scanner and multiecho echo-planar imaging coupled to independent component analysis were acquired preoperatively from 5 study participants who had a right temporoparietooccipital glioblastoma. Seed-based functional connectivity analysis was performed with InstaCorr. Network identification focused on 7 major functional connectivity networks described in the literature and a putative language network centered on Broca's area. RESULTS All 8 functional connectivity networks were identified in each participant. Tumor-related topological changes to the default mode network were observed in all participants. In addition, each participant had at least 1 other abnormal network, and each network was abnormal in at least 1 participant. Individual patterns of network irregularities were identified with a qualitative approach and included local displacement due to mass effect, loss of a functional network component, and recruitment of new regions. CONCLUSIONS Resting-state fMRI can reliably and rapidly detect common functional connectivity networks in patients with glioblastoma and also has sufficient sensitivity for identifying patterns of network alterations. Mapping of functional connectivity networks offers the possibility to expand investigations to less commonly explored neuropsychological processes, such as executive control, attention, and salience. Changes in these networks may allow insights into mechanisms underlying the functional consequences of tumor growth, surgical intervention, and patient rehabilitation.

Neurocognitive Changes Associated With Surgical Resection of Left and Right Temporal Lobe Glioma

BACKGROUND

Little is known regarding the neurocognitive impact of temporal lobe tumor resection.

OBJECTIVE

To clarify subacute surgery-related changes in neurocognitive functioning (NCF) in patients with left (LTL) and right (RTL) temporal lobe glioma.

METHODS

Patients with glioma in the LTL (n = 45) or RTL (n = 19) completed comprehensive pre- and postsurgical neuropsychological assessments. NCF was analyzed with 2-way mixed design repeated-measures analysis of variance, with hemisphere (LTL or RTL) as an independent between-subjects factor and pre- and postoperative NCF as a within-subjects factor.

RESULTS

About 60% of patients with LTL glioma and 40% with RTL lesions exhibited significant worsening on at least 1 NCF test. Domains most commonly impacted included verbal memory and executive functioning. Patients with LTL tumor showed greater decline than patients with RTL tumor on verbal memory and confrontation naming tests. Nonetheless, over one-third of patients with RTL lesions also showed verbal memory decline.

CONCLUSION

In patients with temporal lobe glioma, NCF decline in the subacute postoperative period is common. As expected, patients with LTL tumor show more frequent and severe decline than patients with RTL tumor, particularly on verbally mediated measures. However, a considerable proportion of patients with RTL tumor also exhibit decline across various domains, even those typically associated with left hemisphere structures, such as verbal memory. While patients with RTL lesions may show even greater decline in visuospatial memory, this domain was not assessed. Nonetheless, neuropsychological assessment can identify acquired deficits and help facilitate early intervention in patients with temporal lobe glioma.

A Systematic Review and Meta-Analysis of Studies Examining the Use of Brain Laser Interstitial Thermal Therapy versus Craniotomy for the Treatment of High-Grade Tumors in or near Areas of Eloquence: An Examination of the Extent of Resection and Major Complication Rates Associated with Each Type of Surgery

BACKGROUND

The extent of resection (EOR) of high-grade gliomas (WHO grade III or IV) in or near areas of eloquence is associated with overall patient survival, but with higher major neurocognitive complications.

METHODS

A systematic review and meta-analysis was undertaken of the peer-reviewed literature in order to identify studies which examined EOR or extent of ablation (EOA) and major complications (defined as neurocognitive or functional complications which last >3 months duration after surgery) associated with either brain laser interstitial thermal therapy (LITT) or open craniotomy in high-grade tumors in or near areas of eloquence.

RESULTS

Eight studies on brain LITT (n = 79 patients) and 12 craniotomy studies (n = 1,036 patients) were identified which examined either/both EOR/EOA and complications. Meta-analysis demonstrated an EOA/EOR of 85.4 ± 10.6% with brain LITT versus 77.0 ± 40% with craniotomy (mean difference: 8%; 95% CI: 2-15; p = 0.01; inverse variance, random effects model). Meta-analysis of proportions of major complications for each individual therapy demonstrated major complications of 5.7% (95% CI: 1.8-11.6) and 13.8% (95% CI: 10.3-17.9) for LITT and craniotomy, respectively.

CONCLUSION

In patients presenting with high-grade gliomas in or near areas of eloquence, early results demonstrate that brain LITT may be a viable surgical alternative.

Are nanotheranostics and nanodiagnostics-guided drug delivery stepping stones towards precision medicine?

The progress in medical research has led to the understanding that cancer is a large group of heterogeneous diseases, with high variability between and within individuals. This variability sprouted the ambitious goal to improve therapeutic outcomes, while minimizing drug adverse effects through stratification of patients by the differences in their disease markers, in a personalized manner, as opposed to the strategy of "one therapy fits all". Nanotheranostics, composed of nanoparticles (NPs) carrying therapeutic and/or diagnostics probes, have the potential to revolutionize personalized medicine. There are different modalities to combine these two distinct fields into one system for a synergistic outcome. The addition of a nanocarrier to a theranostic system holds great promise. Nanocarriers possess high surface area, enabling sophisticated functionalization with imaging agents, thus gaining enhanced diagnostic ability in real-time. Yet, most of the FDA-approved theranostic approaches are based on small molecules. The theranostic approaches that are reviewed herein are paving the road towards personalized medicine through all stages of patient care: starting from screening and diagnostics, proceeding to treatment and ending with treatment follow-up. Our current review provides a broad background and highlights new insights for the rational design of theranostic nanosystems for desired therapeutic niches, while summoning the hurdles on their way to become first-line diagnostics and therapeutics for cancer patients.