[PET/CT with 11C-methionine in assessment of brain glioma metabolism]. / Pozitronnaya emissionnaya tomografiya v sochetanii s komp'yuternoi tomografiei i 11S-metioninom v otsenke metabolizma gliom golovnogo mozga.

OBJECTIVE: To study 11C-methionine (MET) metabolism in gliomas using CNS tumor biobank imaging data. MATERIAL AND METHODS: MRI and 11C-MET PET/CT were performed in 225 patients (49±14 years, M/F=84/101) according to standard protocols with analysis of 11C-MET accumulation index and volumetric parameters (V_FLAIR, V_PET and V_PET/FLAIR). These results were compared with molecular genetic testing and 2-year overall survival. RESULTS: We examined 225 patients with gliomas (97 glioblastomas, 70 astrocytomas, 58 oligodendrogliomas). Accumulation index and volume of 11C-MET in glioblastomas were significantly higher in the general group (AI=2.90, Se 69%, Sp 76%, AUC 0.76; V_PET=24.3 cm3, Se 67%, Sp 60%, AUC 0.65; V_PET/FLAIR 0.46, Se 60%, Sp 69%, AUC 0.67) and within the group of astrocytomas (AI=2.93, Se 68%, Sp 89%, AUC 0.84; V_PET=8.06 cm3, Se 91%, Sp 35%, AUC 0.66; V_PET/FLAIR 0.27, Se 77%, Sp 60%, AUC 0.71). The median 2-year overall survival in patients with glioblastomas was 13 months that was significantly lower compared to IDH «+¼ gliomas (p<0.0001). There was a relationship between high accumulation index of 11C-MET and shorter overall survival in patients with glioblastomas. Significantly higher AI >3.59 (Se 89%, Sp 67%, AUC 0.79) was additionally obtained in subgroup of patients with glioblastomas >50 years (n=34) for EGFR «+¼ tumors. CONCLUSION: We found variable 11C-MET metabolism in WHO 2021 gliomas and confirmed significant difference in metabolic activity and volume of 11C-MET accumulation in glioblastomas compared to IDH «+¼ gliomas. Moreover, we revealed the relationship between high accumulation index and shorter survival. Analysis of 11C-MET metabolism in patients over 50 years old revealed higher accumulation index in the EGFR «+¼ group. Further comparison of these imaging methods and assessment of other significant mutations are necessary to identify the anatomical and metabolic patterns of IDH «+¼ gliomas.

Comparison of diagnostic performance of radiologist- and AI-based assessments of T2-FLAIR mismatch sign and quantitative assessment using synthetic MRI in the differential diagnosis between astrocytoma, IDH-mutant and oligodendroglioma, IDH-mutant and 1p/19q-codeleted.

PURPOSE: This study aimed to compare assessments by radiologists, artificial intelligence (AI), and quantitative measurement using synthetic MRI (SyMRI) for differential diagnosis between astrocytoma, IDH-mutant and oligodendroglioma, and IDH-mutant and 1p/19q-codeleted and to identify the superior method. METHODS: Thirty-three cases (men, 14; women, 19) comprising 19 astrocytomas and 14 oligodendrogliomas were evaluated. Four radiologists independently evaluated the presence of the T2-FLAIR mismatch sign. A 3D convolutional neural network (CNN) model was trained using 50 patients outside the test group (28 astrocytomas and 22 oligodendrogliomas) and transferred to evaluate the T2-FLAIR mismatch lesions in the test group. If the CNN labeled more than 50% of the T2-prolonged lesion area, the result was considered positive. The T1/T2-relaxation times and proton density (PD) derived from SyMRI were measured in both gliomas. Each quantitative parameter (T1, T2, and PD) was compared between gliomas using the Mann-Whitney U-test. Receiver-operating characteristic analysis was used to evaluate the diagnostic performance. RESULTS: The mean sensitivity, specificity, and area under the curve (AUC) of radiologists vs. AI were 76.3% vs. 94.7%; 100% vs. 92.9%; and 0.880 vs. 0.938, respectively. The two types of diffuse gliomas could be differentiated using a cutoff value of 2290/128 ms for a combined 90th percentile of T1 and 10th percentile of T2 relaxation times with 94.4/100% sensitivity/specificity with an AUC of 0.981. CONCLUSION: Compared to the radiologists' assessment using the T2-FLAIR mismatch sign, the AI and the SyMRI assessments increased both sensitivity and objectivity, resulting in improved diagnostic performance in differentiating gliomas.

Reliability assessment of methylthioadenosine phosphorylase immunohistochemistry as a surrogate biomarker for CDKN2A homozygous deletion in adult-type IDH-mutant diffuse gliomas.

According to the 2021 World Health Organization classification of brain tumors, astrocytomas containing a CDKN2A/B homozygous deletion (HD) are designated as grade 4 even when no microvascular proliferation and/or necrosis is present. In this study, we aimed to investigate the relationship between CDKN2A HD and loss of methylthioadenosine phosphorylase (MTAP) expression in adult-type IDH-mutant gliomas and to assess the sensitivity and specificity of MTAP immunohistochemistry (IHC) along with interobserver agreement as a surrogate biomarker for CDKN2A HD. Eighty-eight astrocytomas and 71 oligodendrogliomas cases that were diagnosed between 2014 and 2021 at Hacettepe University were selected and tissue microarrays were conducted to perform CDKN2A fluorescence in situ hybridization and MTAP IHC. Twenty-five (15.7%) cases harbored CDKN2A HD. MTAP loss was detected in 28 (15.7%) cases by the first observer and 27 (17%) cases by the second observer. The sensitivity and specificity of MTAP were calculated as 88% and 95.52%-96.27% for 2 observers. A very good/perfect agreement was noted between the observers (Cohen kappa coefficient = 0.938). Intratumoral heterogeneity was observed in 4 cases. MTAP IHC was found to be a reliable surrogate biomarker as a possible alternative to CDKN2A HD identification with a high sensitivity and specificity along with high interobserver agreement.

Contribution of whole slide imaging-based deep learning in the assessment of intraoperative and postoperative sections in neuropathology.

The pathological diagnosis of intracranial germinoma (IG), oligodendroglioma, and low-grade astrocytoma on intraoperative frozen section (IFS) and hematoxylin-eosin (HE)-staining section directly determines patients' treatment options, but it is a difficult task for pathologists. We aimed to investigate whether whole-slide imaging (WSI)-based deep learning can contribute new precision to the diagnosis of IG, oligodendroglioma, and low-grade astrocytoma. Two types of WSIs (500 IFSs and 832 HE-staining sections) were collected from 379 patients at multiple medical centers. Patients at Center 1 were split into the training, testing, and internal validation sets (3:1:1), while the other centers were the external validation sets. First, we subdivided WSIs into small tiles and selected tissue tiles using a tissue tile selection model. Then a tile-level classification model was established, and the majority voting method was used to determine the final diagnoses. Color jitter was applied to the tiles so that the deep learning (DL) models could adapt to the variations in the staining. Last, we investigated the effectiveness of model assistance. The internal validation accuracies of the IFS and HE models were 93.9% and 95.3%, respectively. The external validation accuracies of the IFS and HE models were 82.0% and 76.9%, respectively. Furthermore, the IFS and HE models can predict Ki-67 positive cell areas with R2 of 0.81 and 0.86, respectively. With model assistance, the IFS and HE diagnosis accuracy of pathologists improved from 54.6%-69.7% and 53.5%-83.7% to 87.9%-93.9% and 86.0%-90.7%, respectively. Both the IFS model and the HE model can differentiate the three tumors, predict the expression of Ki-67, and improve the diagnostic accuracy of pathologists. The use of our model can assist clinicians in providing patients with optimal and timely treatment options.

Utility of real-time polymerase chain reaction for the assessment of CDKN2A homozygous deletion in adult-type IDH-mutant astrocytoma.

The World Health Organization Classification of Tumors of the Central Nervous System 5th Edition (WHO CNS5) introduced a newly defined astrocytoma, IDH-mutant grade 4, for adult diffuse glioma classification. One of the diagnostic criteria is the presence of a CDKN2A/B homozygous deletion (HD). Here, we report a robust and cost-effective quantitative polymerase chain reaction (qPCR)-based test for assessing CDKN2A HD. A TaqMan copy number assay was performed using a probe located within CDKN2A. The linear correlation between the Ct values and relative CDKN2A copy number was confirmed using a serial mixture of DNA from normal blood and U87MG cells. The qPCR assay was performed in 109 IDH-mutant astrocytomas, including 14 tumors with CDKN2A HD, verified either by multiplex ligation-dependent probe amplification (MLPA) or CytoScan HD microarray platforms. Receiver operating characteristic curve analysis indicated that a cutoff value of 0.85 yielded optimal sensitivity (100%) and specificity (99.0%) for determining CDKN2A HD. The assay applies to DNA extracted from frozen or formalin-fixed paraffin-embedded tissue samples. Survival was significantly shorter in patients with than in those without CDKN2A HD, assessed by either MLPA/CytoScan or qPCR. Thus, our qPCR method is clinically applicable for astrocytoma grading and prognostication, compatible with the WHO CNS5.

[Analysis of the difference in MGMT promoter status in gliomas and its significance in prognosis assessment].

The data of 1 268 newly diagnosed gliomas from the Fourth Ward of Neurosurgery Department of Beijing Tiantan Hospital between April 2013 and March 2022 were retrospectively analyzed. Based on postoperative pathology, the gliomas were divided into groups: oligodendrogliomas (n=308), astrocytomas (n=337) and glioblastomas (n=623). According to the O6-methylguanine-DNA methyl transferase (MGMT) promoter status defined by the 12% of best cut-off value in previous research results, patients were divided into methylation group (n=763) and non-methylation group (n=505). Methylation level [M (Q1, Q3)] in patients with glioblastoma, astrocytoma and oligodendroglioma was 6% (2%, 24%), 17% (10%, 28%) and 29% (19%, 40%), respectively (P<0.001). Compared with non-methylation patients, the progression-free survival (PFS) and overall survival (OS) of glioblastomas patients with methylation of MGMT promoter demonstrated more favorable prognosis [M (Q1, Q3)]) of PFS: 14.0 (6.0, 36.0) months vs 8.0 (4.0, 15.0) months, P<0.001; M (Q1, Q3) of OS: 29.0 (17.0, 60.5) months vs 16.0 (11.0, 26.5) months, P<0.001]. In astrocytomas patients, the PFS was much longer for those with methylation [the median PFS of patients with methylation was not observed at the end of follow-up, but those without methylation showed a median PFS of 46.0 (29.0, 52.0) months] (P=0.001). However, no statistically significant difference was observed in OS [the median OS of patients with methylation was not observed at the end of follow-up, but those without methylation had a median OS of 62.0 (46.0, 98.0) months] (P=0.085). In oligodendrogliomas patients, no statistically significant differences of PFS and OS were observed between patients with methylation and those without methylation. MGMT promoter status was a related factor affecting PFS and OS in glioblastomas (PFS: HR=0.534,95%CI: 0.426-0.668, P<0.001; OS: HR=0.451, 95%CI: 0.353-0.576, P<0.001). Moreover, MGMT promoter status was also a related factor affecting PFS in astrocytomas (HR=0.462, 95%CI: 0.221-0.966, P=0.040), but not for OS (HR=0.664, 95%CI: 0.259-1.690, P=0.389). The methylation level of MGMT promoter differed substantially in different types of gliomas, and the status of MGMT promoter profoundly affected the prognosis of glioblastomas.

A Population-Based Study of Treatment and Survival in Older Glioma Patients.

BACKGROUND: Population-based analyses of patterns of care and survival of older patients diagnosed with grade II-III oligodendroglioma (OLI) or astrocytoma (AST) can aid clinicians in their understanding and care of these patients. METHODS: We identified patients diagnosed between 2006 and 2015 with primary glioma diagnoses (OLI or AST) who were older than 65 years using the latest release of the Surveillance, Epidemiology, and End Results-Medicare-linked database. Medicare claims were used to identify cancer treatments (surgery, chemotherapy, and radiation therapy) from 2006 to 2016. Kaplan-Meier methodology was used to describe overall survival (OS). Cox proportional hazards regression was used to associate variables of interest, including treatments in a time-dependent manner, with OS. Hazard ratios (HRs) and 95% confidence intervals (CIs) from multivariable, cause-specific competing risk models identified associations with treatments. All statistical tests were 2-sided. RESULTS: We identified 1291 patients comprising 158 with OLI, 1043 with AST, and 90 with mixed histologies. Median OS was 6.5 (95% CI = 6.1 to 7.3) months for the overall cohort, 22.6 (95% CI = 13.9 to 33.1) months for OLI, and 5.8 (95% CI = 5.3 to 6.4) months for AST. Patients who received surgery and patients who received both chemotherapy and radiation therapy in combination experienced better OS (HR = 0.87, 95% CI = 0.79 to 0.96, and HR = 0.58, 95% CI = 0.35 to 0.96, respectively). Over the time frame studied, there was a 4.0% increase per year in prescription of chemotherapy (P = .03) and a 2.0% improvement in OS for each calendar year (P = .003). CONCLUSIONS: We provide population-based evidence that patients older than 65 years with grade II-III glioma have experienced increased chemotherapy use as well as improvement in survival over time.

Assessment of therapeutic outcome and role of reirradiation in patients with radiation-induced glioma.

BACKGROUND: We sought to clarify the optimal follow-up, therapeutic strategy, especially the role of reirradiation, and the diagnostic impact of isocitrate dehydrogenase (IDH) 1 and 2 mutation status in patients with radiation-induced glioma (RIG). METHODS: We retrospectively reviewed the clinical characteristics and treatment outcomes of 11 patients with high-grade glioma who satisfied Cahan's criteria for RIG in our database during 2001-2021. IDH 1/2 mutations were analyzed by Sanger sequencing and/or pyrosequencing. RESULTS: The RIGs included glioblastoma with IDH 1/2 wild-type (n = 7), glioblastoma not otherwise specified (n = 2), anaplastic astrocytoma with IDH1/2 wild-type (n = 1), and anaplastic astrocytoma not otherwise specified (n = 1). The median period from primary disease and RIG diagnosis was 17 years (range: 9-30 years). All patients underwent tumor removal or biopsy, 5 patients postoperatively received reirradiation combined with chemotherapy, and 6 patients were treated with chemotherapy alone. The median progression-free and survival times were 11.3 and 28.3 months. The median progression-free survival time of patients treated with reirradiation and chemotherapy (n = 5) tended to be longer than that of patients that received chemotherapy alone (n = 6) (17.0 vs 8.1 months). However, the median survival time was similar (29.6 vs 27.4 months). Local recurrence was observed in 5 patients treated with chemotherapy alone, whereas in 2 patients among 4 patients treated with reirradiation and chemotherapy. None of the patients developed radiation necrosis. In one case, the primary tumor was diffuse astrocytoma with IDH2 mutant, and the secondary tumor was glioblastoma with IDH 1/2 wild-type. Based on the difference of IDH2 mutation status, the secondary tumor with IDH 1/2 wild-type was diagnosed as a de novo tumor that was related to the previous radiation therapy. CONCLUSIONS: RIG can occur beyond 20 years after successfully treating the primary disease using radiotherapy; thus, cancer survivors should be informed of the long-term risk of developing RIG and the need for timely neuroimaging evaluation. Reirradiation combined with chemotherapy appears to be feasible and has favorable outcomes. Determining the IDH1/2 mutational status is useful to establish RIG diagnosis when the primary tumor is glioma.

Utility of methylthioadenosine phosphorylase immunohistochemical deficiency as a surrogate for CDKN2A homozygous deletion in the assessment of adult-type infiltrating astrocytoma.

Homozygous deletion (HD) of CDKN2A is one of the most promising biomarkers for predicting poor prognosis of IDH-mutant diffuse gliomas. The Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy (cIMPACT-NOW) recommendations propose that IDH-mutant lower-grade astrocytomas with CDKN2A/B HD be classified as grade IV tumors. Loss of methylthioadenosine phosphorylase (MTAP) immunohistochemistry staining has been proposed as a surrogate of CDKN2A HD in various tumors but its performance has not been fully investigated in diffuse glioma. This study determined whether MTAP immunoreactivity could serve as a proxy for CDKN2A HD in adult-type diffuse glioma, thereby contributing to stratifying patient outcome. MTAP immunohistochemistry staining using clone EPR6893 was scored in 178 diffuse glioma specimens consisting of 77 IDH-mutant astrocytomas, 13 IDH-mutant oligodendrogliomas, and 88 IDH-wildtype glioblastomas. The use of MTAP immunohistochemical deficiency to predict CDKN2A HD was good for IDH-mutant astrocytomas (sensitivity, 88%; specificity, 98%) and IDH-wildtype glioblastomas (sensitivity, 89%; specificity, 100%), but poor for IDH-mutant oligodendrogliomas (sensitivity, 67%; specificity, 57%). Both CDKN2A HD and MTAP immunohistochemical deficiency were significant adverse prognostic factors of overall survival for IDH-mutant astrocytoma (P < 0.001 each), but neither were prognostically significant for oligodendroglioma or IDH-wildtype glioblastoma. IDH-mutant lower-grade astrocytoma with CDKN2A HD and deficient MTAP immunoreactivity exhibited overlapping unfavorable outcome with IDH-mutant glioblastoma. MTAP immunostaining was easily interpreted in 61% of the cases tested, but scoring required greater care in the remaining cases. An alternative MTAP antibody clone (2G4) produced identical scoring results in all but 1 case, and a slightly larger proportion (66%) of cases were considered easy to interpret compared to using EPR6893. In summary, loss of MTAP immunoreactivity could serve as a reasonable predictive surrogate for CDKN2A HD in IDH-mutant astrocytomas and IDH-wildtype glioblastomas and could provide significant prognostic value for IDH-mutant astrocytoma, comparable to CDKN2A HD.

Feasibility of performance-based functional assessment in brain tumour survivors.

INTRODUCTION: Rehabilitation and exercise interventions are beneficial for the physical and psychological health of cancer survivors. Current clinic-based performance status measures do not accurately capture the survivor's functioning, or rehabilitation and exercise needs. Our primary objective was to explore the feasibility of performing a performance-based functional assessment with brain tumour survivors as a means to inform needs for rehabilitation and exercise. METHODS: A feasibility study was conducted with survivors of brain and other neurological cancers attending new patient or follow-up clinics. Survivors were assessed using the Short Physical Performance Battery (SPPB), grip strength and Rosow-Breslau Physical Activity Self-Assessment (RSB). RESULTS: We approached 40 survivors with brain tumours, and 30 agreed to participate in the study. The SPPB was inversely correlated with Eastern Cooperative Oncology Group (ECOG) scores (r = -.73; p < .01), but scores on the SPPB for individuals classified as ECOG 1 ranged from 5 to 12 out of 12, indicating a large variability in functional scores within this ECOG grade. CONCLUSION: Implementation of objective functional testing is feasible in the neuro-oncology outpatient clinic. The SPPB appears to best inform the functional status of survivors with brain tumours, facilitating more individualised exercise and rehabilitation referrals.

Rehabilitación de las funciones ejecutivas en un caso de oligoastrocitoma frontal derecho / Rehabilitation of executive functions in a case of right frontal oligoastrocytoma

El desarrollo tecnológico y científico en salud de los últimos años ha permitido mejoras en el diagnóstico y mayor eficacia en el tratamiento de pacientes con tumores cerebrales, generado un aumento no solo en la supervivencia, sino también una mayor demanda de los servicios de neuropsicología y rehabilitación, debido a las alteraciones cognitivas asociadas y dificultades en cuanto a la funcionalidad e independencia, disminuyendo significativamente la calidad de vida de estos pacientes. La presente investigación documenta el caso de un paciente masculino de 43 años, remitido al servicio de neuropsicología tras la resección de oligoastrocitoma frontal derecho, en la evaluación neuropsicológica se evidenció alteraciones en funciones ejecutivas, fluidez de lenguaje discursivo y dificultad en habilidades instrumentales. La investigación se realizó bajo el diseño cuasi experimental de caso único, donde se aplicó en repetidas ocasiones a lo largo del tratamiento el Inventario de Adaptabilidad Mayo-Portland (MPAI-4) para determinar las dificultades funcionales del paciente. El objetivo de la rehabilitación neuropsicológica se centró en implementar estrategias de autoinstrucciones y automonitoreo, que pudieran ser aplicadas en contextos cotidianos y en intereses específicos del paciente. Los resultados indican que el proceso de rehabilitación neuropsicológica demostró tener un efecto positivo en la funcionalidad del paciente y las estrategias aprendidas pueden ser trasladadas a su vida cotidiana

The technological and scientific development on health in recent years has allowed improvements in diagnosis and treatment on brain tumor patients, have increase not only their survivor rate but also their need of neuropsychology and rehabilitation services due to cognitive alterations associated and the subsequent struggling with independence and functionality that reduces significantly their life quality. The present research documents the case of a male patient, 43 years old, referred to the service after resection of right frontal oligoastrocytoma, in the neuropsychologic evaluation evidenced executive functions, discursive language fluency alterations and difficulties in instrumental skills. The research was carried out under the quasi experimental design of a single case where there will be applied repeatedly during the course of treatment the Mayo-Portland Adaptability Inventory (MPAI-4) to identify functional difficulties on the patient. The objective of the neuropsychological rehabilitation focuses on implementing self-instruction and self-observance strategies in order to apply them on an ordinary context and the patient's specific areas of interest. The results indicate that the neuropsychological rehabilitation treatment has shown a positive effect on the patient's functionality and an improvement on his ability to apply the learned strategies to his day to day life.

Expression-based decision tree model reveals distinct microRNA expression pattern in pediatric neuronal and mixed neuronal-glial tumors.

BACKGROUND: The understanding of the molecular biology of pediatric neuronal and mixed neuronal-glial brain tumors is still insufficient due to low frequency and heterogeneity of those lesions which comprise several subtypes presenting neuronal and/or neuronal-glial differentiation. Important is that the most frequent ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNET) showed limited number of detectable molecular alterations. In such cases analyses of additional genomic mechanisms seem to be the most promising. The aim of the study was to evaluate microRNA (miRNA) profiles in GGs, DNETs and pilocytic asytrocytomas (PA) and test the hypothesis of plausible miRNA connection with histopathological subtypes of particular pediatric glial and mixed glioneronal tumors. METHODS: The study was designed as the two-stage analysis. Microarray testing was performed with the use of the miRCURY LNA microRNA Array technology in 51 cases. Validation set comprised 107 samples used during confirmation of the profiling results by qPCR bioinformatic analysis. RESULTS: Microarray data was compared between the groups using an analysis of variance with the Benjamini-Hochberg procedure used to estimate false discovery rates. After filtration 782 miRNAs were eligible for further analysis. Based on the results of 10 × 10-fold cross-validation J48 algorithm was identified as the most resilient to overfitting. Pairwise comparison showed the DNETs to be the most divergent with the largest number of miRNAs differing from either of the two comparative groups. Validation of array analysis was performed for miRNAs used in the classification model: miR-155-5p, miR-4754, miR-4530, miR-628-3p, let-7b-3p, miR-4758-3p, miRPlus-A1086 and miR-891a-5p. Model developed on their expression measured by qPCR showed weighted AUC of 0.97 (95% CI for all classes ranging from 0.91 to 1.00). A computational analysis was used to identify mRNA targets for final set of selected miRNAs using miRWalk database. Among genomic targets of selected molecules ZBTB20, LCOR, PFKFB2, SYNJ2BP and TPD52 genes were noted. CONCLUSIONS: Our data showed the existence of miRNAs which expression is specific for different histological types of tumors. miRNA expression analysis may be useful in in-depth molecular diagnostic process of the tumors and could elucidate their origins and molecular background.

A Multiplex Quantitative Reverse Transcription Polymerase Chain Reaction Assay for the Detection of KIAA1549-BRAF Fusion Transcripts in Formalin-Fixed Paraffin-Embedded Pilocytic Astrocytomas.

BACKGROUND AND OBJECTIVE: Genomic duplications and fusion involving BRAF and KIAA1549 that create fusion proteins with constitutive B-RAF kinase activity are a hallmark of pilocytic astrocytomas (PAs). The detection of KIAA1549-BRAF fusion transcripts is of paramount importance to classify these tumors and to identify patients who could benefit from BRAF inhibitors. In a clinical setting, the available material for molecular analysis from these pediatric tumors is often limited to formalin-fixed paraffin-embedded (FFPE) tissue. The aim of the present study was to develop a new method to detect the three most frequent KIAA1549-BRAF fusion transcripts, 15-9, 16-11, and 16-9, where numbers refer to the exons fused together, using a FFPE-compatible multiplex quantitative reverse transcription polymerase chain reaction (qRT-PCR). METHODS: We compared performance of the assay to a reference singleplex method on a collection of 46 FFPE PAs. RESULTS: The results showed that both methods are comparable. The multiplex method had an overall 97% sensitivity and 100% specificity compared to the singleplex method, and agreement between the two techniques was almost perfect (Cohen's kappa: 0.97). There was no evidence of a significant difference between the qRT-PCR efficiencies of the multiplex technique and of the singleplex assay for all fusion transcripts and for GAPDH, the latter used as a reference gene. The multiplex method consumed four times less complementary DNA (cDNA), cost less, and required half the hands-on technical time. CONCLUSION: The results show that it could be beneficial to implement the multiplex method in a clinical setting, where samples presenting low quantity of degraded RNA are not unusual.

Intraoperative assessment of isocitrate dehydrogenase mutation status in human gliomas using desorption electrospray ionization-mass spectrometry.

OBJECTIVE: The authors describe a rapid intraoperative ambient ionization mass spectrometry (MS) method for determining isocitrate dehydrogenase (IDH) mutation status from glioma tissue biopsies. This method offers new glioma management options and may impact extent of resection goals. Assessment of the IDH mutation is key for accurate glioma diagnosis, particularly for differentiating diffuse glioma from other neoplastic and reactive inflammatory conditions, a challenge for the standard intraoperative diagnostic consultation that relies solely on morphology. METHODS: Banked glioma specimens (n = 37) were analyzed by desorption electrospray ionization-MS (DESI-MS) to develop a diagnostic method to detect the known altered oncometabolite in IDH-mutant gliomas, 2-hydroxyglutarate (2HG). The method was used intraoperatively to analyze tissue smears obtained from glioma patients undergoing resection and to rapidly diagnose IDH mutation status (< 5 minutes). Fifty-one tumor core biopsies from 25 patients (14 wild type [WT] and 11 mutant) were examined and data were analyzed using analysis of variance and receiver operating characteristic curve analysis. RESULTS: The optimized DESI-MS method discriminated between IDH-WT and IDH-mutant gliomas, with an average sensitivity and specificity of 100%. The average normalized DESI-MS 2HG signal was an order of magnitude higher in IDH-mutant glioma than in IDH-WT glioma. The DESI 2HG signal intensities correlated with independently measured 2HG concentrations (R2 = 0.98). In 1 case, an IDH1 R132H-mutant glioma was misdiagnosed as a demyelinating condition by frozen section histology during the intraoperative consultation, and no resection was performed pending the final pathology report. A second craniotomy and tumor resection was performed after the final pathology provided a diagnosis most consistent with an IDH-mutant glioblastoma. During the second craniotomy, high levels of 2HG in the tumor core biopsies were detected. CONCLUSIONS: This study demonstrates the capability to differentiate rapidly between IDH-mutant gliomas and IDH-WT conditions by DESI-MS during tumor resection. DESI-MS analysis of tissue smears is simple and can be easily integrated into the standard intraoperative pathology consultation. This approach may aid in solving differential diagnosis problems associated with low-grade gliomas and could influence intraoperative decisions regarding extent of resection, ultimately improving patient outcome. Research is ongoing to expand the patient cohort, systematically validate the DESI-MS method, and investigate the relationships between 2HG and tumor heterogeneity.

Differentiation between pilocytic astrocytoma and glioblastoma: a decision tree model using contrast-enhanced magnetic resonance imaging-derived quantitative radiomic features.

OBJECTIVE: To differentiate brain pilocytic astrocytoma (PA) from glioblastoma (GBM) using contrast-enhanced magnetic resonance imaging (MRI) quantitative radiomic features by a decision tree model. METHODS: Sixty-six patients from two centres (PA, n = 31; GBM, n = 35) were randomly divided into training and validation data sets (about 2:1). Quantitative radiomic features of the tumours were extracted from contrast-enhanced MR images. A subset of features was selected by feature stability and Boruta algorithm. The selected features were used to build a decision tree model. Predictive accuracy, sensitivity and specificity were used to assess model performance. The classification outcome of the model was combined with tumour location, age and gender features, and multivariable logistic regression analysis and permutation test using the entire data set were performed to further evaluate the decision tree model. RESULTS: A total of 271 radiomic features were successfully extracted for each tumour. Twelve features were selected as input variables to build the decision tree model. Two features S(1, -1) Entropy and S(2, -2) SumAverg were finally included in the model. The model showed an accuracy, sensitivity and specificity of 0.87, 0.90 and 0.83 for the training data set and 0.86, 0.80 and 0.91 for the validation data set. The classification outcome of the model related to the actual tumour types and did not rely on the other three features (p < 0.001). CONCLUSIONS: A decision tree model with two features derived from the contrast-enhanced MR images performed well in differentiating PA from GBM. KEY POINTS: • MRI findings of PA and GBM are sometimes very similar. • Radiomics provides much more quantitative information about tumours. • Radiomic features can help to distinguish PA from GBM.

Long-term health and social function in adult survivors of paediatric astrocytoma: A report from the Childhood Cancer Survivor Study.

BACKGROUND: Although paediatric astrocytoma has an excellent 5-year survival rate, survivors remain at risk for morbidity and late mortality. This study aimed to estimate the risk of late mortality, chronic conditions, poor health status and social impairment in ageing paediatric astrocytoma survivors. METHODS: We longitudinally evaluated 1182 5-year astrocytoma survivors diagnosed between 1970 and 1986 and 4023 siblings enrolled in a retrospective cohort study. Kaplan-Meier estimates of late mortality and cumulative incidence of serious chronic conditions were estimated. Cox regression models provided hazard ratios (HRs) with 95% confidence intervals (CIs) for development of chronic conditions, and generalised linear models provided relative risks (RRs) of the poor health status and social outcomes. RESULTS: At 30 years from diagnosis, cumulative late mortality was 22.1% (CI 20.0-24.3%), primarily due to disease progression or recurrence. Compared with siblings, survivors were at increased risk of serious chronic conditions (HR 4.6, CI 3.8-5.5). Survivors reported higher rates of poor general health (RR 3.3, CI 2.8-3.8), poor mental health (RR 1.9, CI 1.7-2.1), functional impairment (RR 9.0, CI 7.7-10.5) and activity limitation (RR 3.6, CI 3.1-4.2) and lower rates of college graduation (RR 0.75, CI 0.69-0.82), marriage (RR 0.62, CI 0.58-0.66), employment (RR 0.75, CI 0.72-0.79) and household income ≥$40,000 (RR 0.68, CI 0.64-0.73). Even survivors without radiation exposure had elevated risk of chronic conditions, poor health status and social impairment compared with siblings. CONCLUSIONS: Survivors of paediatric astrocytoma are at high risk for long-term complications of their disease and its treatment. They require lifelong monitoring for late effects.

Everolimus compliance and persistence among tuberous sclerosis complex patients with renal angiomyolipoma or subependymal giant cell astrocytoma.

OBJECTIVE: Everolimus is the only FDA approved drug to treat renal angiomyolipoma or subependymal giant-cell astrocytoma (SEGA) in tuberous sclerosis complex (TSC). Potential differences exist between patients with commercial and Medicaid insurance on everolimus use; however, there is limited information from the real world. This study compared compliance and persistence of everolimus between commercial and Medicaid patients using US claims data. METHODS: Patients with ≥1 claim of TSC with renal angiomyolipoma or SEGA were selected from the MarketScan commercial (1 January 2009-31 August 2016) and Medicaid (1 January 2009-30 June 2015) databases. Patients were followed from index date (the earliest date of TSC, renal angiomyolipoma or SEGA diagnosis) to death or end of data. Non-persistence, defined as ≥60 day gap without everolimus, and medication possession ratio (MPR) were assessed among the subset of patients with ≥1 year of follow-up from the first everolimus claim. RESULTS: A total of 1497 TSC patients met the study criteria (896 renal angiomyolipoma only, 411 SEGA only and 190 both). Compared to Medicaid patients (N = 513), commercial patients (N = 984) had the same ages (22 years) but a shorter length of follow-up (38 vs. 48 months, p < .001). Medicaid and commercial patients had similar rates of being treated with everolimus (14.4% vs. 13.6%, p = .668), but it took Medicaid patients a longer time to start everolimus (871 vs. 704 days, p < .001). Although the non-persistence rate was not significantly different between commercial and Medicaid patients (42.5% vs. 35.1%, p = .561), the number of days from everolimus initiation to non-persistence was significantly lower for commercial patients (945 vs. 1132, p < .001). During the 1 year post everolimus initiation, commercial patients had a significantly higher MPR (0.81 vs. 0.74, p < .001) and higher percentage of patients with MPR ≥0.80 (67.8% vs. 58.1%, p < .001). CONCLUSIONS: Among TSC patients with renal angiomyolipoma or SEGA and treated with everolimus, everolimus MPR was between 0.74 and 0.81. Medicaid patients had lower MPR than commercial patients but better persistence.

Assessment of the impact of glioma diagnostic reclassification following the new 2016 WHO classification on a series of cases. / Evaluación del impacto del cambio diagnóstico de los gliomas aplicando la nueva clasificación de la OMS de 2016 sobre una serie de casos.

BACKGROUND AND OBJECTIVES: The aim of this project is to assess diagnostic reclassification based on molecular data over morphology in a series of glial tumours since the introduction of the 2016 WHO classification of brain tumours. MATERIALS AND METHODS: Retrospective review of glial tumours (oligodendrogliomas and astrocytomas) treated in our centre between January 2012 and June 2016 in which a review of diagnosis was performed when molecular studies were added. Statistical analysis included evaluation of variables of epidemiology, morphology and molecular data (mainly IDH mutation and 1p19q codeletion), diagnostic changes after new classification was considered, and clinical impact in cases of diagnostic reclassification. RESULTS: From a total of 147 glial tumours reviewed in our centre, molecular diagnosis was obtained in 74 cases (50.3%). Initial diagnosis changed in 23 cases (31%), and 20 (87%) of them had a prior histological diagnosis of oligodendroglioma (69.6% grade ii and 17.4% grade iii). Only 3 of these 23 cases diagnosis changed from astrocytoma to oligodendroglioma. Among reclassified tumours, there was a common molecular pattern, as findings showed mutant IDH in 16 cases (69.6%) and no codeletion in 20 cases (87%). According to the cell of origin, of the whole group of 27 oligodendrogliomas in our series (reclassified and non-reclassifed), 20 cases (74%) became astrocytomas, despite typical oligodendroglial morphology, due to absence of 1p19q codeletion. There was a trend for diagnosis reclassification in younger patients (<40 years), P=.065, mainly in those with a prior diagnosis of oligodendroglioma, with no statistical differences based on gender or clinical data. Besides, reclassification was more common among tumours with mutant IDH (69.6%), P=.003, than those with wild type IDH. In terms of survival, despite receiving different treatments, no significant changes were detected between reclassified and non-reclassified tumours after a mean follow-up of 16 months, partly related to lower grade of these lesions. CONCLUSIONS: Within the spectrum of the glial tumours treated in our institution, this new classification including molecular genetics over morphological data has provided marked diagnostic changes. These changes appear mainly in tumours previously diagnosed as oligodendrogliomas and in younger patients, with molecular patterns of mutant IDH and 1p19q codeletion. Although diagnosis reclassification may affect clinic, prognosis or therapeutic management of these tumours, deeper and prospective studies on these specific aspects are needed.

Grading and proliferation assessment of diffuse astrocytic tumors with monoexponential, biexponential, and stretched-exponential diffusion-weighted imaging and diffusion kurtosis imaging.

PURPOSE: To compare the main parameters derived from monoexponential, biexponential and stretched-exponential diffusion-weighted imaging (DWI) and diffusion kurtosis imaging (DKI) with respect to diagnostic performance for tumor grading and proliferation assessment in diffuse astrocytic tumors (DATs). MATERIALS AND METHODS: Fifty-eight pathologically confirmed DAT patients who underwent DWI and DKI on a 3-T scanner were prospectively collected and retrospectively reviewed. Measurements including the apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudodiffusion coefficient (D*), perfusion fraction (f), distributed diffusion coefficient (DDC), heterogeneity index (α), mean diffusivity (MD), fractional anisotropy (FA), and mean kurtosis (MK) were compared between tumor grades (Ⅱ, Ⅲ, and Ⅳ) by using a Jonckheere-Terpstra test. Receiver operating characteristic (ROC) curves were used to assess the diagnostic efficacy of these parameters. Spearman's rho with the Ki-67 labeling index (LI) was calculated for each parameter. RESULTS: MK values differed significantly between all DAT subtypes and increased with grade. The ADC, D, f, DDC, α and MD values were significantly higher in grade Ⅱ tumors than in grade Ⅲ/Ⅳ tumors. D* values were significantly lower in grade Ⅱ tumors than in grade Ⅳ tumors (all P < 0.05). In discriminating between grade Ⅱ and Ⅲ tumors, α, MK, MD, D and f had significantly greater area under the ROC curve (AUC) values than D* and FA (0.927, 0.901, 0.896, 0.895, and 0.889, respectively vs 0.659 and 0.598, respectively, P < 0.05). In discriminating between grade Ⅲ and Ⅳ tumors, only MK demonstrated acceptable discrimination (AUC = 0.711). MK and D showed a strong correlation with the Ki-67 LI (ρ = 0.791 and -0.789, respectively, P < 0.001). D*, f, MD, ADC, DDC and α showed a moderate correlation (|ρ| ranged from 0.415 to 0.698, P < 0.05). CONCLUSION: MK and D have considerable potential to predict the degree of proliferation of DATs. MK could effectively characterize microstructural changes throughout the malignant transformation of DATs and provided useful complementary information for grading.