bluuebunny/crossref_metadata_2025_split huggingface dataset:
NIMG-66. RADIOGENOMICS-BASED HETEROGENEITY ANALYSIS OF GLIOBLASTOMA REVEALS MR IMAGING PHENOTYPICAL CHARACTERIZATION OF EGFR MUTATIONS
Authors: Yu Fanyang , Guo Jun , Kazerooni Anahita Fathi , Akbari Hamed , Toorens Erik , Sako Chiharu , Mamourian Elizabeth , Bagley Stephen J , Binder Zev , Lustig Robert A , Brem Steven , O'Rourke Donald M , Ganguly Tapan , Bakas Spyridon , Nasrallah MacLean P , Chaudhari Pratik , Davatzikos Christos 
Published: November 2023

Abstract

PURPOSE
EGFR is one of the most frequently altered genes in glioblastoma, while also being an attractive therapeutic target for treatment. Having in vivo, imaging-based markers of EGFR mutations, and as well as characterizing molecular heterogeneity, are important for patient management and stratification into trials. Toward this end, we present deep learning models of imaging signatures of EGFR mutations built from MRI.

METHODS
Our cohort consists of 286 glioblastoma patients with multi-parametric MRI (mpMRI) scans (T1, T1-Gd, T2, T2-FLAIR, DSC, DTI). Radiomics features, including histograms, morphologic and textural descriptors, were first derived. Genomic information was determined from a targeted next generation sequencing (NGS) panel. We jointly trained a variational auto-encoder and a multi-label classifier for predicting 4 key driver genes EGFR, NF1, PTEN, TP53 to learn a latent representation reflecting the molecular heterogeneity in the dataset. The latent representation was analyzed using principal component analysis (PCA). We calculated the Euclidean distance between imaging features of tumors with EGFR plus 1 of the other 3 mutations, from those of tumors having only EGFR mutations. We also analyzed the imaging signatures and variant allele frequencies (VAFs) of individuals with multiple (typically 3-4) resected tissue samples (n=49).

RESULTS
Co-occurrence of mutations in any of NF1, PTEN, TP53 genes with EGFR mutations resulted into dominance of imaging signatures of these other mutations over that of EGFR mutations. Interestingly, tumors with homogeneously high VAFs in EGFR mutations (n=3) exhibit strong phenotypical difference from the exclusive EGFR mutated group, while individuals with heterogeneous EGFR mutations (n=4) do not show such differences.

CONCLUSION
Our preliminary findings suggest EGFR imaging characteristics can be dominated by those of other co-occurring mutations. Tumors with homogeneously high VAFs, potentially indicating presence of germline EGFR mutations, lead to relatively distinct imaging phenotypes.
NIMG-67. REVISITING GLIOMATOSIS CEREBRI IN ADULT-TYPE DIFFUSE GLIOMAS: A COMPREHENSIVE ANALYSIS OF MANIFESTATION AND RISK FACTORS IN THE 2021 WHO CLASSIFICATION
Authors: Shin Ilah , Park Yae Won , Ahn Sung Soo , Chang Jong Hee 
Published: November 2023

Abstract

BACKGROUND
To investigate the incidence, clinicopathologic and imaging correlations and prognostic implications of gliomatosis cerebri (GC) pattern in adult-type diffuse glioma patients reflecting the 2021 WHO classification.

METHODS
Retrospective chart and imaging review was performed in 1,211 adult-type diffuse glioma patients at a single institution between 2005 and 2021. Clinicopathologic and imaging features were compared amongst adult-type diffuse glioma patients with and without GC based on the 2021 WHO classification. Clinical and imaging risk factors for predicting IDH mutation status within GC patients were investigated. Survival analysis was performed in entire patients and in subgroup of IDH-wildtype glioblastoma patients to evaluate whether GC is an independent prognostic factor.

RESULTS
Total 99 patients (8.9% of entire patients) showed GC. The distribution of tumor type was significantly different in patients with GC compared with those without GC (P = 0.017); IDH-wildtype glioblastoma being most common (77.8% vs. 68.9%), followed by IDH-mutant astrocytoma (16.2% vs 16.9%), and being less common in oligodendroglioma (6.1% vs 16.5%). Contrast enhancement, necrosis, cystic change, hemorrhage, and GC type 2 were independent risk factors for predicting IDH mutation status in GC patients. GC remained as an independent prognostic factor (HR=1.55, P=0.031) in IDH-wildtype glioblastoma patients on multivariable analyses.

CONCLUSIONS
The incidence of GC is 8.9% in adult-type diffuse gliomas, with IDH-wildtype glioblastoma showing significantly higher risk of GC. Preoperative imaging features may predict IDH mutation status in GC patients. GC is an independent prognostic factor in IDH-wildtype glioblastoma, and promote recognition of this pattern in clinical settings.
NIMG-73. RADIOGRAPHIC CHANGES AFTER RADIATION THERAPY IN SUBTOTALLY RESECTED ATYPICAL MENINGIOMAS
Authors: Yim Eunji , Pan Peter , Ivanidze Jana , Chiang Gloria , Pannullo Susan , Knisely Jonathan , Brandmaier Andrew , Fine Howard , Ramakrishna Rohan , Schwartz Theodore , Stieg Philip , Liechty Benjamin , Pisapia David , Magge Rajiv 
Published: November 2023

Abstract

BACKGROUND
Adjuvant radiotherapy (RT) has been shown to improve outcomes after subtotal resection (STR) of atypical meningioma, but little is known about how tumors evolve on magnetic resonance imaging (MRI) and whether this correlates with RT response.

METHODS
We retrospectively identified histologically confirmed cases of WHO Grade II atypical meningioma at a large academic institution from 2004-2020 who underwent subtotal resection and received radiation. Clinicodemographic, surgical, RT, and histopathologic data were collected, as well as clinical outcomes, with a median follow-up time of 69 months (IQR 61). Patients were stratified by external beam RT (EBRT) and stereotactic radiosurgery (SRS). Radiographic data included tumor location, cerebral edema, susceptibility changes, leptomeningeal enhancement, calcification, necrosis, and time to recurrence. Progression was defined by radiology report.

RESULTS
Of 31 patients with STR for newly diagnosed atypical meningioma, 65% (20 of 31) received RT and 11 of 20 (55%) received EBRT while nine received SRS. Of the convexity/parasagittal meningiomas (N=10), 40% demonstrated venous sinus invasion. 65% (N=13) of cases were treated upfront; the other seven progressed at a median 9.4 months before undergoing RT. Post-RT, 74% decreased in size (N=5) or stabilized (N=9); imaging was not available for one case. Recurrence after RT was observed in five cases. 11 cases developed restricted diffusion at median onset of 24.9 months; 7 developed adjacent leptomeningeal enhancement at median onset of 14.7 months, of which 86% (6 of 7) received SRS. Other patterns included adjacent nodular (N=3) and linear (N=2) enhancement, and adjacent confluent T2 signal (N=4); these could potentially represent radiation-related changes. Only one case developed calcification after 70 months.

CONCLUSIONS
Atypical meningiomas exhibit variable patterns of evolution after RT which may predict treatment outcomes. Multivariate analysis is planned to correlate radiographic changes with pathology characteristics, RT modality, and time to recurrence.
NIMG-75. POSTOPERATIVE68GA-DOTATATE/PET-CT IMAGING IS PROGNOSTIC FOR PROGRESSION-FREE SURVIVAL IN MENINGIOMA WHO GRADE 1: A PROSPECTIVE SINGLE-CENTER STUDY
Authors: Teske Nico , Biczok Annamaria , Quach Stefanie , Dekorsy Franziska J , Forbrig Robert , Bodensohn Raphael , Niyazi Maximilian , Tonn Joerg-Christian , Albert Nathalie , Schichor Christian , Ueberschaer Moritz 
Published: November 2023

Abstract

PURPOSE
Microsurgical tumor resection represents the first-line treatment for symptomatic meningiomas, and extent of resection has been shown to be of prognostic importance. Assessment of tumor remnants with somatostatin receptor PET proves to be superior to intraoperative estimation with Simpson grading or MRI. However, prognostic relevance of postoperative PET for progression-free survival in meningiomas remains unclear.

METHODS
We conducted a prospective study including patients with surgically removed meningioma WHO grade 1 and collected clinical and imaging data. All patients received postoperative MRI and 68Gallium-DOTATATE/PET, and were followed regularly with MRI surveillance scans for detection of tumor recurrence/progression.

RESULTS
We included 46 patients with 49 tumors. Mean age at diagnosis was 57.8 ± 1.7 years with a male-to-female ratio of 1:1.7. Local tumor progression occurred in 7/49 patients (14%) after a median follow-up of 52 months. Positive PET was associated with an increased risk for progression (*p = 0.015) and a lower progression-free survival (*p = 0.029) whereas MRI was not. 20/20 patients (100%) with negative PET findings remained recurrence-free. Location of recurrence/progression on MRI was adjacent to regions where postoperative PET indicated tumor remnants in all cases. Gross tumor volumes were higher on PET compared to MRI (*p = 0.032).

CONCLUSION
Our data show that 68Ga-DOTATATE/PET is highly sensitive in revealing tumor remnants in patients with meningioma WHO grade 1. Negative PET findings were associated with a higher progression-free survival, thus improving surveillance. In patients with tumor remnants, additional PET can optimize adjuvant radiotherapy target planning of surgically resected meningiomas.
NIMG-82. FET PET SENSITIVITY IN PRIMARY BRAIN TUMORS ACCORDING TO CNS WHO 2021: VALUE AND PITFALLS IN PRESURGICAL IMPLEMENTATION
Authors: Oster Christoph , Blau Tobias , Keyvani Kathy , Schmidt Teresa , Lazaridis Lazaros , Agkatsev Sarina , Sure Ulrich , Kleinschnitz Christoph , Scheffler Björn , Barbato Francesco , Herrmann Ken , Kebir Sied , Glas Martin 
Published: November 2023

Abstract

BACKGROUND
FET-PET imaging has emerged as a valuable tool in the characterization of unclear brain lesions that cannot be clearly diagnosed with conventional diagnostic methods. In 2021, the Central Nervous System (CNS) World Health Organization (WHO) introduced significant changes in the classification of CNS tumors. Notably, under the new classification, certain cases of WHO grade II glioma may be reclassified as glioblastoma. Unfortunately, a subset of grade II gliomas, as defined by the 2016 WHO classification, may exhibit no detectable FET uptake and lack contrast enhancement on MRI, which can lead to underestimation of such tumors and potentially result in inappropriate treatment decisions, including avoiding surgery. Question: In how many cases did the diagnostics consisting of MRI and FET PET underestimate the malignancy in unclear brain lesions?

METHODS
In this study, we conducted a retrospective analysis of all patients who underwent FET PET imaging of the brain between 2017 and June 2021, prior to their first surgical brain intervention. We obtained the results from presurgical MRI-scans and categorized the lesions based on whether they exhibited contrast media enhancement or not, in addition to the postsurgical molecular-histopathologic diagnosis. Our analysis focused on identifying the number of cases in which the diagnosis of malignancy was underestimated in the context of the WHO 2016 classification. To further investigate these cases, we conducted NGS and 850k-analysis to reclassify the results in accordance with the new CNS WHO 2021 classification.

RESULTS
After enrolling 85 patients, our study found that according to the 2016 classification, preoperative imaging underestimated malignancy in 14 cases (16%) where histopathological analysis revealed high-grade malignant brain tumors. In 32 cases (27%), the preoperative imaging correctly suggested a malignant tumor, which was later confirmed by histopathological analysis after surgery. The final results of this reclassification after the CNS-WHO-2021 will be presented at SNO-meeting.
NIMG-84. COMPARISON OF TRADITIONAL AND ADVANCED DEEP-LEARNING PATIENT SPECIFIC REGISTRATION METHODS IN PRESERVING TUMOR HABITAT IN GLIOBLASTOMA TUMORS: A PRELIMINARY STUDY
Authors: Safai Apoorva , Pineda Gustavo , Yadav Ipsa , Ismail Marwa , Tiwari Pallavi 
Published: November 2023

Abstract

PURPOSE
Registration of patient specific pre and post operative MRI scans in Glioblastoma patients is crucial to assess tumor progression, effect of radiation, and chemotherapy and survival prediction. However, in brain tumors longitudinal registration is challenging as tumor resection and mass effects causes tissue deformations and missing intensity correspondence across longitudinal scans. In this study, we compared effectiveness of traditional registration algorithms with state-of-the-art computationally extensive deep learning (DL) models in preserving intensity of tumor regions.

METHODS
Brain MRI scans (T1w,T1c,T2w,FLAIR) of 14 glioblastoma patients with first (tp1), intermediate (tp2) and follow up post operative scans (tp3) were obtained from two publicly available dataset (LUMIERE, XCURE). Preprocessing involved co-registration of all modalities within a timepoint, skull stripping, and uniformity in image dimensions, orientation, and origin across all timepoints. Tumor scans at tp2 and tp3 were registered to tp1 for all modalities independently, using different registration algorithms such as the traditional affine and symmetric diffeomorphic (SyN) registration with and without tumor masks using the ANTs software, along with the MICCAI-registration challenge winner DL algorithm (DIRAC). Intensity distribution of registered and unregistered scans for tp2 and tp3 were compared using the earth mover’s distance (EMD).

RESULTS
Traditional affine (tp2-0.074±0.06, tp3:0.058±0.051) and SyN (tp2-0.048±0.031 ,tp3:0.075±0.074) registration algorithm using T2w modality provided lower average EMD than DL method (tp2-0.624±0.69,tp3-0.595±0.67). Intensity distribution was better preserved for scans from intermediate timepoints compared to the post operative scans.

CONCLUSION
Our preliminary assessment suggests that traditional registration methods when implemented on pre-aligned MRI scans may better preserve image intensities in brain tumors scans compared to advanced and computationally expensive DL methods.
NIMG-86. ESTIMATING BRAIN TUMOR RELATED EDEMA FROM NON-INVASIVE IMAGING IN A CLINICALLY RELEVANT TIMELINE
Authors: Jackson Pamela , Ranjbar Sara , Singleton Kyle , Swanson Kristin 
Published: November 2023

Abstract
Image-based mathematical modeling is emerging as an advantageous tool to integrate into the care routine for patients with brain tumors. These tools can be used for a variety of tasks including predicting tumor growth, indicating spatial genomic alterations, and guiding radiation therapy. Often, the methods to produce these maps are developed in silos, using cohorts of retrospective patients and switching to a per patient map calculation can be an afterthought. Automatic pipelines are needed to enable creating mathematical maps in a clinically-relevant workflow. To this end, we developed a pipeline to create an image-based mathematical map of edema abundance based on T2-weighted (T2W) magnetic resonance imaging that includes preprocessing steps, abnormality and tissue type segmentation, brain extraction, map generation, and conversion between image file formats. The python-based pipeline was designed to take in T1-weighted (T1W), T1W with gadolinium contrast (T1Gd), T2W, and fluid attenuated inversion recovery (FLAIR) DICOM images for a single patient as input and convert them to NIfTIs for downstream steps. The pipeline preprocessed images by correcting bias field fluctuations using the N4 algorithm and normalizing intensities. The T1W, T1Gd, and FLAIR are then registered to the T2W. T1Gd and FLAIR are used in a deep learning algorithm to delineate the brain and abnormality including enhancing tumor, necrosis, and peripheral edema. Normal tissue segmentations are performed using the statistical parametric mapping (SPM) segmentation routine. The segmentations and preprocessed images are all utilized in the edema mathematical model. The resulting edema map is then reformatted as a DICOM and output for further use by clinicians and clinical imaging systems. Our future goals include integrating our pipeline in a clinical workstation and sending final maps to our hospital’s picture archiving and communication system (PACS) to allow for deployment of these models for patient care in a clinically efficient timeline.
NCMP-04. INITIAL REPORT OF BOSWELLIA SERRATA FOR MANAGEMENT OF CEREBRAL RADIATION NECROSIS AFTER STEREOTACTIC RADIOSURGERY FOR BRAIN METASTASES
Authors: Upadhyay Rituraj , Elguindy Ahmed Nader Mohammed , Sengupta Soma , Wang Kyle , Beyer Sasha , Thomas Evan , Raval Raju , Palmer Joshua 
Published: November 2023

Abstract

BACKGROUND
Radiation necrosis(RN) is a concerning late toxicity after radiation therapy(RT) for brain metastases(BM). Oral corticosteroids are the mainstay of management; however, not optimal given multiple side effects, particularly with the emergence of immunotherapy. Boswellia serrata(BS) is an over-the-counter supplement shown to reduce cerebral edema after brain RT. We evaluated the response rates with BS in a series of BM patients treated with stereotactic radiosurgery(SRS) who developed RN.

METHODS
We enrolled patients who developed RN after SRS for BM from 2020-2022 and were treated with BS 4.2-4.5g daily. Response was assessed using Response Assessment in Neuro-Oncology(RANO) criteria. Primary endpoint was ≥25% decrease in edema volume on T2-FLAIR MRI from baseline.

RESULTS
Fifty patients received BS for Grade 1-3 CTCAE v5.0 RN (G1=11, G2=36, and G3=3). Median time to RN was 10 months(m) after SRS and median follow-up was 6m. Best response was a complete response(CR) in 15% patients and partial response(PR) in 40% while 35% had stable disease(SD) and 10% had progression. At 3 , 6 , 9 and 12 months of follow-up respectively, 25%, 60%, 43% and 50% patients had any response(CR or PR). About 56% patients had symptomatic RN, of which 35.7% had improvement in symptoms with BS alone, while 64% required steroid use. Overall, median duration of response in patients with CR, PR or SD was 7.5m(range 2-31m). Salvage treatment for RN was steroids(33), surgery(4), Bevacizumab(5) or hyperbaric oxygen(1). No patient had ≥ CTCAE grade 3 toxicities, while 6% had grade 1-2 gastrointestinal intolerance. Overall, 39 patients remained on BS at last follow-up or death.

CONCLUSION
We observed &gt; 50% response rates with use of BS in patients with grade 1-3 RN after SRS. Over 1/3rd patients with symptomatic RN were able to avoid long-term steroid use. Further prospective studies comparing Boswellia with placebo are warranted.
NCMP-06. INTRAMEDULLARY SPINAL CORD METASTASIS OF RENAL CELL CARCINOMA: A COMPARISON OF CASES AND TREATMENT OUTCOMES
Authors: Fukushima Corinna , Kuzel Timothy 
Published: November 2023

Abstract
Renal cell carcinoma (RCC) intramedullary spinal cord metastasis (ISCM) is a rare but frequently devastating diagnosis. Due to its rarity, there is currently no clear standard of care for RCC ISCM management. However, with improvements in metastatic RCC management and imaging for early detection of ISCM, we may see a rise in the incidence of RCC patients developing ISCM, for which treatment guidelines are lacking. Here, we aim to add to the growing body of RCC ISCM literature with two cases- one with ISCM managed with surgery, radiation, and immunotherapy, and the other managed with only radiation, immunotherapy, and chemotherapy. Case 1 is a 47 year old male with RCC and lung and bone metastases who underwent nephrectomy, lobectomy, high dose IL-2 therapy, and immunotherapy. He later developed worsening low back pain, and lower extremity paresthesias and weakness. Imaging revealed a thoracic metastasis for which he was started on steroids, underwent surgical resection followed by radiation therapy, and immunotherapy. Serial imaging and clinical exams have not found evidence of ISCM recurrence 5 years after initial resection. Case 2 is a 74 year old female with RCC with cerebellar metastasis who underwent nephrectomy, suboccipital craniotomy with mass resection, radiation therapy, and immunotherapy. 3 years later, she developed neck pain with right arm paresthesias, and imaging revealed cervical spine ISCM. Patient declined surgical intervention, and she was managed with steroids and radiation therapy, followed by chemotherapy. Approximately 5 years after initial ISCM findings, serial imaging and clinical exams have not revealed evidence of disease progression. These cases have several important differences including prior central nervous system metastases, ISCM location, and surgical intervention. However, both have not shown evidence of disease progression at similar time points. We hope these cases add to the small body of cases to move towards developing treatment guidelines.
NCMP-10. DEXAMETHASONE: A TOOL AND A PROBLEM IN GLIOBLASTOMA MANAGEMENT
Authors: Mohammad Amro , Jatana Sukhdeep , Sakalla Rawan , Davalan William , Khalaf Roy , Li Hongda , Aberra Rebecca , Carias Mathew , Al-saadi Tariq , Guevara-Moriones Natalia , Ruiz-Barrera Miguel Angel , Mindru Chritina , Diaz Roberto 
Published: November 2023

Abstract
Glioblastoma (GBM) patient morbidity and overall survival (OS) are associated with dexamethasone use. We studied dexamethasone-associated hyper-glycemia, leukocytosis, and accompanying complications in the peri-operative period. We also examined the effect of metformin treatment on GBM patient OS. We retrospectively studied 243 GBM patients admitted between 2014-2018. Patients with peri-operative glucose measurements and adequate follow-up to assess for complications were included. Metformin was used for treatment of diabetes or in the management of glucocorticoid-induced hyper-glycemia. Kaplan-Meier curves and log-rank p test were used for univariate analysis. Cox-proportional hazards model was used to generate adjusted hazard ratios for multivariate analysis. Dexamethasone dose was associated with hyper-glycemia and leukocytosis post-operatively. Poor glycemic control was associated with increased odds of 30-day any complication on univariate analysis and 30-day any complication and increased length of stay on multivariate analysis. We then demonstrated that metformin improved OS in methylated O6-methylguanine DNA methyltransferase gene (MGMT) promoter tumor patients (652 days, 95% CI 327 – 897, n = 25 vs 394 days, 95% CI 210 – 513, n = 63; P = .049). Non-diabetic MGMT-methylated tumor patients treated with metformin also had an improved median OS of 736 days, 95% CI 365 – 1036, n = 11 vs 395 days, 95% CI 210 – 513, n = 66; P = .01). Overall, peri-operative hyper-glycemia and higher average dexamethasone use are associated with poor glycemic control and leukocytosis. As a result, dexamethasone can increase the risk of peri-operative complications in GBM patients. Avoiding hyper-glycemia by limiting dexamethasone use or using Metformin may decrease the risk of complications and improve OS.