A Consensus Definition of Supratotal Resection for Anatomically Distinct Primary Glioblastoma: An AANS/CNS Section on Tumors Survey of Neurosurgical Oncologists

Introduction: Supratotal resection (SpTR) of glioblastoma may be associated with improved survival, but published results have varied in part from lack of consensus on the definition and appropriate use of SpTR. A previous small survey of neurosurgical oncologists with expertise performing SpTR found resection 1-2 cm beyond contrast enhancement was an acceptable definition and glioblastoma involving the right frontal and bilateral anterior temporal lobes were considered most amenable to SpTR. The general neurosurgical oncology community has not yet confirmed the practicality of this definition. Methods Seventy-six general neurosurgical oncology members of the AANS/CNS Tumor Section were surveyed using a crowdsourcing approach. Participants were presented with 11 definitions of SpTR and rated each definition’s appropriateness. Participants additionally reviewed magnetic resonance imaging for 10 anatomically distinct glioblastomas and assessed the tumor location's eloquence, perceived equipoise of enrolling patients in a randomized trial comparing gross total to SpTR, and their personal treatment plans. Results Fifty-two neurosurgeons (73.2%) agreed that resection 1-2 cm beyond contrast enhancement was an acceptable definition for SpTR. Cases were divided into three anatomically distinct groups by perceived equipoise between gross total and SpTR. The best clinical trial candidates were right anterior temporal (n=58, 76.3%) and right frontal (n=55, 73.3%) glioblastomas. Conclusion Support exists within the neurosurgical oncology community to adopt the proposed consensus definition of SpTR of glioblastoma and to treat right anterior temporal and right frontal glioblastomas using SpTR. A smaller proportion of general neurosurgical oncologists than SpTR experts consider SpTR feasible in the left anterior temporal lobe.

Convolutional Neural Network Based Brain Tumor Classification Using Robust Background Saliency Detection

To perceive the tumors found in brain and their treatment, experts manually note and identify different Regions of Interest (ROI). To overcome the faults and divergences during this state, automated analysis is performed. A unique technique is used to classify the tumor section of the brain from an MRI is proposed using saliency-focused image depiction and optimization in classification based on CNN. Primarily, the MRI images are pre-processed using the Canny Edge Finding algorithm and then those images are represented as saliency driven based on Robust Background Saliency Detection (RBD). Followed by the abstraction of features then classifying the image is performed using CNN along with ADAM optimization. The implementation is accomplished, and the results are analyzed, showing that it outperforms previous techniques.

Engineering a Vascularized Hypoxic Tumor Model for Therapeutic Assessment

Solid tumors in advanced cancer often feature a structurally and functionally abnormal vasculature through tumor angiogenesis, which contributes to cancer progression, metastasis, and therapeutic resistances. Hypoxia is considered a major driver of angiogenesis in tumor microenvironments. However, there remains a lack of in vitro models that recapitulate both the vasculature and hypoxia in the same model with physiological resemblance to the tumor microenvironment, while allowing for high-content spatiotemporal analyses for mechanistic studies and therapeutic evaluations. We have previously constructed a hypoxia microdevice that utilizes the metabolism of cancer cells to generate an oxygen gradient in the cancer cell layer as seen in solid tumor sections. Here, we have engineered a new composite microdevice-microfluidics platform that recapitulates a vascularized hypoxic tumor. Endothelial cells were seeded in a collagen channel formed by viscous fingering, to generate a rounded vascular lumen surrounding a hypoxic tumor section composed of cancer cells embedded in a 3-D hydrogel extracellular matrix. We demonstrated that the new device can be used with microscopy-based high-content analyses to track the vascular phenotypes, morphology, and sprouting into the hypoxic tumor section over a 7-day culture, as well as the response to different cancer/stromal cells. We further evaluated the integrity/leakiness of the vascular lumen in molecular delivery, and the potential of the platform to study the movement/trafficking of therapeutic immune cells. Therefore, our new platform can be used as a model for understanding tumor angiogenesis and therapeutic delivery/efficacy in vascularized hypoxic tumors.

Concentration of cisplatin-incorporated polymeric micelles in a murine solid tumor evaluated using PIXE analysis

We report an elemental analysis of murine solid tumors treated with cisplatin-incorporated polymeric micelles (NC-6004) to evaluate the concentration of the drug in the tumor tissue using conventional particle-induced X-ray emission (PIXE) analysis, as well as the spatial distribution in the tumor section using sub-millimeter PIXE analysis. The results reveal that the platinum concentration in the tumor treated with NC-6004 was higher than in that treated with cisplatin, whereas no significant difference was found in platinum concentration between NC-6004 and cisplatin samples in the normal tissue. This suggests that NC-6004 can both provide therapeutic efficacy and reduce the side effects caused by conventional treatment using cisplatin. These results show that PIXE analysis is a powerful tool for research into drug delivery systems.