Successful desensitization in a patient with recurrent anaplastic oligodendroglioma presenting with procarbazine-mediated anaphylaxis.

INTRODUCTION: Procarbazine is an oral chemotherapeutic agent used in the treatment of brain malignancies and is associated with hypersensitivity reactions. In case of grade 4 reactions, rechallenge should be avoided, and the agent should be replaced, unless the treatment is curative, in which case the application of a desensitization protocol should be considered. We present a successful case of desensitization in procarbazine anaphylaxis. CASE REPORT: A 53-year-old male patient was diagnosed with recurrent anaplastic oligodendroglioblastoma. The patient received three cycles of procarbazine, lomustine, and vincristine chemotherapy for malignancy recurrence. In the fourth cycle, on the 12th day of procarbazine treatment, the patient developed anaphylaxis. Procarbazine was given together with premedication as part of the 12-step desensitization process, and the fourth cycle was successfully completed. MANAGEMENT AND OUTCOME: Procarbazine hypersensitivity reactions are observed less frequently than reactions to other chemotherapeutics. We presented a case of procarbazine-associated severe anaphylaxis that was able to continue procarbazine chemotherapy with successful desensitization. This case is important in terms of confirming the procarbazine desensitization protocol. DISCUSSION: In literature there is only one protocol developed was successfully applied in one patient with procarbazine anaphylaxis. In the current case, we took this protocol into consideration in the management of our patient. Following the use of this protocol, the patient was able to continue procarbazine chemotherapy successfully. Procarbazine anaphylaxis is rare, and more cases are needed to be reported to confirm the desensitization protocol and when to continue procarbazine treatment.

T2-Fluid-attenuated inversion recovery (FLAIR) pseudoprogression in patients with anaplastic oligodendrogliomas treated with procarbazine, lomustine and vincristine (PCV) chemotherapy alone.

BACKGROUND: Pseudoprogression in gliomas has been extensively described after radiotherapy with or without chemotherapy, but not after chemotherapy alone. Here we describe the occurrence of pseudoprogression in patients with anaplastic oligodendrogliomas treated with postoperative procarbazine, lomustine and vincristine (PCV) chemotherapy alone. METHODS: We retrospectively reviewed the medical and radiological files of patients with 1p/19q codeleted, IDH-mutant anaplastic oligodendrogliomas treated with PCV chemotherapy alone who presented magnetic resonance imaging (MRI) modifications suggestive of tumour progression and in whom the final diagnosis was a pseudoprogression. RESULTS: We identified six patients. All patients underwent a surgical resection and were treated with PCV chemotherapy without radiotherapy. After a median of 11 months following the initiation of chemotherapy (range: 3-49 months), the patients developed asymptomatic white matter MRI modifications around the surgical cavity leading to the suspicion of a tumour progression. These modifications appeared as hyperintense on T2-fluid-attenuated inversion recovery (FLAIR) sequence, hypointense on T1 sequence, and lacked mass effect (0/6), contrast enhancement (0/6), restriction on diffusion-weighted imaging (0/4), relative cerebral blood volume (rCBV) increase on perfusion MRI (0/4), and hypermetabolism on 18 F-fluoro-L-dopa positron emission tomography (18 F-DOPA PET) scan (0/3). One patient underwent a surgical resection demonstrating no tumour recurrence; the five other patients were considered as having post-therapeutic modifications based on imaging characteristics. After a median follow-up of 4 years all patients were progression-free. CONCLUSIONS: Anaplastic oligodendroglioma patients treated with postoperative PCV chemotherapy alone occasionally develop T2/FLAIR hyperintensities around the surgical cavity that can wrongly suggest tumour progression. Multimodal imaging and close follow-up should be considered in this situation.

Malignant Glioma.

This chapter provides a comprehensive overview of malignant gliomas, the most common primary brain tumor in adults. These tumors are varied in their cellular origin, genetic profile, and morphology under the microscope, but together they share some of the most dismal prognoses of all neoplasms in the body. Although there is currently no cure for malignant glioma, persistent efforts to improve outcomes in patients with these tumors have led to modest increases in survival, and researchers worldwide continue to strive toward a deeper understanding of the factors that influence glioma development and response to treatment. In addition to well-established epidemiology, clinical manifestations, and common histopathologic and radiologic features of malignant gliomas, this section considers recent advances in molecular biology that have led to a more nuanced understanding of the genetic changes that characterize the different types of malignant glioma, as well as their implications for treatment. Beyond the traditional classification of malignant gliomas based on histopathological features, this chapter incorporates the World Health Organization's 2016 criteria for the classification of brain tumors, with special focus on disease-defining genetic alterations and newly established subcategories of malignant glioma that were previously unidentifiable based on microscopic examination alone. Traditional therapeutic modalities that form the cornerstone of treatment for malignant glioma, such as aggressive surgical resection followed by adjuvant chemotherapy and radiation therapy, and the studies that support their efficacy are reviewed in detail. This provides a foundation for additional discussion of novel therapeutic methods such as immunotherapy and convection-enhanced delivery, as well as new techniques for enhancing extent of resection such as fluorescence-guided surgery.

Characteristics of Anaplastic Oligodendrogliomas Short-Term Survivors: A POLA Network Study.

BACKGROUND: Anaplastic oligodendrogliomas IDH-mutant and 1p/19q codeleted (AO) occasionally have a poor outcome. Herein we aimed at analyzing their characteristics. METHODS: We retrospectively analyzed the characteristics of 44 AO patients with a cancer-specific survival <5 years (short-term survivors, STS) and compared them with those of 146 AO patients with a survival ≥5 years (classical survivors, CS) included in the POLA network. RESULTS: Compared to CS, STS were older (P = .0001), less frequently presented with isolated seizures (P < .0001), more frequently presented with cognitive dysfunction (P < .0001), had larger tumors (P = .= .003), a higher proliferative index (P = .= .0003), and a higher number of chromosomal arm abnormalities (P = .= .02). Regarding treatment, STS less frequently underwent a surgical resection than CS (P = .= .0001) and were more frequently treated with chemotherapy alone (P = .= .009) or with radiotherapy plus temozolomide (P = .= .05). Characteristics independently associated with STS in multivariate analysis were cognitive dysfunction, a number of mitosis > 8, and the absence of tumor resection. Based on cognitive dysfunction, type of surgery, and number of mitosis, patients could be classified into groups of standard (18%) and high (62%) risk of <5 year survival. CONCLUSION: The present study suggests that although STS poor outcome appears to largely result from a more advanced disease at diagnosis, surgical resection may be particularly important in this population.

A single institution retrospective analysis on survival based on treatment paradigms for patients with anaplastic oligodendroglioma.

INTRODUCTION: Anaplastic oligodendrogliomas are high-grade gliomas defined molecularly by 1p19q co-deletion. There is no curative therapy, and standard of care includes surgical resection followed by radiation and chemotherapy. However, the benefit of up-front radiation with chemotherapy compared to chemotherapy alone has not been demonstrated in a randomized control trial. Given the potential long-term consequences of radiation therapy, such as cognitive impairment, arteriopathy, endocrinopathy, and hearing/visual impairment, there is an effort to balance longevity with radiation toxicity. METHODS: We performed a retrospective single institution analysis of survival of patients with anaplastic oligodendroglioma over 20 years. RESULTS: 159 patients were identified as diagnosed with an anaplastic oligodendroglioma between 1996 and 2016. Of those, 40 patients were found to have AO at original diagnosis and had documented 1p19q co-deletion with a median of 7.1 years of follow-up (range: 0.6-16.7 years). After surgery, 45 % of patients were treated with radiation and chemotherapy at diagnosis, and 50 % were treated with adjuvant chemotherapy alone. The group treated with chemotherapy alone had a trend of receiving more cycles of chemotherapy than patients treated with radiation and chemotherapy upfront (p = 0.051). Median overall survival has not yet been reached. The related risk of progression in the upfront, adjuvant chemotherapy only group was almost 5-fold higher than the patients who received radiation and chemotherapy (hazard ratio = 4.85 (1.74-13.49), p = 0.002). However, there was no significant difference in overall survival in patients treated with upfront chemotherapy compared to patients treated upfront with chemotherapy and radiation (p = 0.8). Univariate analysis of age, KPS, extent of resection, or upfront versus delayed radiation was not associated with improved survival. CONCLUSIONS: Initial treatment with adjuvant chemotherapy alone, rather than radiation and chemotherapy, may be an option for some patients with anaplastic oligodendroglioma, as it is associated with similar overall survival despite shorter progression free survival.

Challenges and Perspectives of Standard Therapy and Drug Development in High-Grade Gliomas.

Despite their low incidence rate globally, high-grade gliomas (HGG) remain a fatal primary brain tumor. The recommended therapy often is incapable of resecting the tumor entirely and exclusively targeting the tumor leads to tumor recurrence and dismal prognosis. Additionally, many HGG patients are not well suited for standard therapy and instead, subjected to a palliative approach. HGG tumors are highly infiltrative and the complex tumor microenvironment as well as high tumor heterogeneity often poses the main challenges towards the standard treatment. Therefore, a one-fit-approach may not be suitable for HGG management. Thus, a multimodal approach of standard therapy with immunotherapy, nanomedicine, repurposing of older drugs, use of phytochemicals, and precision medicine may be more advantageous than a single treatment model. This multimodal approach considers the environmental and genetic factors which could affect the patient's response to therapy, thus improving their outcome. This review discusses the current views and advances in potential HGG therapeutic approaches and, aims to bridge the existing knowledge gap that will assist in overcoming challenges in HGG.

[Anaplastic astrocytoma and anaplastic oligodendroglioma of the brain: current state of the problem]. / Anaplasticheskie astrotsitomy i anaplasticheskie oligodendrogliomy golovnogo mozga: sovremennoe sostoyanie problemy.

This review is devoted to the problem of anaplastic cerebral gliomas. The authors consider classification, neuroimaging of these tumors including comparison of magnetic resonance imaging and positron emission tomography data. Clinical manifestations of anaplastic gliomas, issues of their histological and molecular genetic classification are discussed. Moreover, the authors compare the data of neuroimaging and genetic examinations of tumors. Other issues are multicomponent treatment and prognosis in patients with anaplastic glioma of the brain.

Anaplastic oligodendroglioma metastasizing to the bone marrow: a unique case report and literature review.

Oligodendrogliomas are a rare type of primary brain tumor. They are genetically defined as diffuse gliomas carrying mutation in isocitrate dehydrogenase type 1 (IDH1) or type 2 (IDH2) and codeletion of chromosomes 1p and 19q. The WHO grading system distinguishes two histopathologic grades of ODs: grade II (low-grade) and grade III (anaplastic oligodendroglioma or AO). These tumors rarely metastasize outside of central nervous system with only few cases reported in the literature. Here we present a case of an AO, which metastasized to the bone marrow and other sites within a year of diagnosis despite aggressive treatment measures. Our patient eventually succumbed to his disease, raising many questions about this rare condition, its natural course and optimal management strategy.

[IDH、TERT and 1p/19q predicting clinical outcomes in patients with anaplastic oligodendroglioma].

Objective: To investigate the prognostic values of IDH, TERT and 1p/19q in patients with anaplastic oligodendroglioma. Methods: In the study, 66 patients with pathological diagnosis of anaplastic oligodendroglioma were enrolled (The First Affiliated Hospital of Zhengzhou University 2011 to 2016 years). Kaplan-Meier method was used to calculate the survival rates. Log-rank was used to calculate the differences in group. Chi-square testwas used tocalculate the differences in common factor group. Cox regression model was used to conduct multivariate analysis. Results: The median survival time of IDH-wt and IDH-mt subgroups were 16.10 and 42.00 months with statistical significance (P=0.001). The median survival time of 1p/19q codeleted and 1p/19q noncodeleted subgroups were 42.00 and 22.40 months with statistical significance (P=0.012). IDH-mt and 1p/19q codeleted predicted better survivals compared with IDH-wt and 1p/19q noncodeleted (P=0.001). And IDH-mt and 1p/19q noncodeleted predicted better survivals compared with IDH-wt and 1p/19q noncodeleted (P=0.041), too. Multivariate survival analysis demonstrated that Molecular groups was an independent factor to evaluate the prognosis of anaplastic oligodendroglioma (P=0.008). Conclusion: IDH-mtand (or) 1p/19q codeletedpredicted better survivals in patients with anaplastic oligodendroglioma. IDH and 1p/19q deleted might be a biomarker for predicting prognosis of patients with anaplastic oligodendroglioma.

[Repetitive resection and intrasurgery radiation therapy of brain malignant gliomas: history of question and modern state of problem]. / Povtornaia rezektsiia i intraoperatsionnaia luchevaia terapiia zlokachestvennykh gliom golovnogo mozga: istoricheskii ékskurs i sovremennoe sostoianie problemy.

Numerous studies have shown that the degree of primary resection of malignant gliomas of the brain (MG) directly correlates with rates of relapse-free and overall patient survival. Currently, there is no unequivocal opinion regarding the indications and effectiveness of repeated resection in relapse of MG after combined treatment. Surgical intervention, taking into account the pathomorphological features of these tumors, is not healing and should be supplemented with certain methods of adjuvant treatment. The article reviews and analyzes publications devoted to repeated resection and various methods of intraoperative radiation therapy in the treatment of MG. Based on the analysis, the authors of the article came to the conclusion that it is advisable to start their own research on the use of intraoperative balloon brachytherapy in the treatment of recurrent MG based on modern technological solutions.

A case of radiation-induced osteosarcoma of the skull presenting as a cutaneous epidermotropic tumor with a short latent period.

Radiation-induced sarcoma (RIS) is an unusual but well documented tumor. The frequency of RIS of the head and neck region has been reported as 0.143%. In the literature the median interval between irradiation and development of sarcoma is 11 years. Cases of RIS with a short latent period, that is, less than 4 years are rare. We report a case of a 34-year-old female who developed an osteosarcoma of the scalp, over a previous craniotomy scar, 3 years after excision of a frontal anaplastic oligodendroglioma which had been followed by a course of 6 weeks radiotherapy (58 Gy) and 6 cycles of temozolomide. The histological features were those of a high-grade osteosarcoma with epidermotropism of tumor cells. Lymph nodes were partially replaced by high-grade metastatic osteosarcoma, with extra-nodal lymphatic tumor thrombi. To our knowledge the only other case report of post-radiation osteosarcoma with a short latency period was a case of osteosarcoma in the craniofacial bone 3 years after radiotherapy for maxillary squamous cell carcinoma. The histological finding of prominent replacement of the epidermis by osteosarcoma has not been reported before.

Expression of Oligodendrocyte Precursor Cell Markers in Canine Oligodendrogliomas.

Oligodendroglioma is a common brain tumor in dogs, particularly brachycephalic breeds. Oligodendrocyte precursor cells (OPCs) are suspected to be a possible origin of oligodendroglioma, although it has not been well elucidated. In the present study, 27 cases of canine brain oligodendrogliomas were histologically and immunohistochemically examined. The most commonly affected breed was the French Bulldog ( n = 19 of 27, 70%). Seizure was the most predominant clinical sign ( n = 17 of 25, 68%). The tumors were located mainly in the cerebrum, particularly in the frontal lobe ( n = 10 of 27, 37%). All cases were diagnosed as anaplastic oligodendroglioma (AO) and had common histologic features characterized by the proliferation of round to polygonal cells with pronounced atypia and conspicuous mitotic activity (average, 10.7 mitoses per 10 high-power fields). Honeycomb pattern ( n = 5 of 27, 19%), myxoid matrix ( n = 10, 37%), cyst formation ( n = 6, 22%), necrosis ( n = 19, 70%), pseudopalisading ( n = 5, 18.5%), glomeruloid vessels ( n = 16, 59%), and microcalcification ( n = 5, 19%) were other histopathologic features of the present tumors. Immunohistochemically, the tumor cells were positive for Olig2 in all cases and for other markers of OPCs in most cases, including SOX10 ( n = 24 of 27, 89%), platelet-derived growth factor receptor α ( n = 24, 89%), and NG2 ( n = 23, 85%). The present AO also consisted of heterogeneous cell populations that were positive for nestin ( n = 13 of 27, 48%), glial fibrillary acidic protein ( n = 5, 19%), doublecortin ( n = 22, 82%), and ßIII-tubulin ( n = 15, 56%). Moreover, cultured AO cells obtained from 1 case retained expression of OPC markers and exhibited multipotent characteristics in a serum culture condition. Overall, the findings suggest that transformed multipotent OPCs may be a potential origin of canine AO.

Cerebrospinal fluid dissemination of high-grade gliomas following boron neutron capture therapy occurs more frequently in the small cell subtype of IDH1R132H mutation-negative glioblastoma.

We have used boron neutron capture therapy (BNCT) to treat patients in Japan with newly diagnosed or recurrent high-grade gliomas and have observed a significant increase in median survival time following BNCT. Although cerebrospinal fluid dissemination (CSFD) is not usually seen with the current standard therapy of patients with glioblastoma (GBM), here we report that subarachnoid or intraventricular CSFD was the most frequent cause of death for a cohort of our patients with high-grade gliomas who had been treated with BNCT. The study population consisted of 87 patients with supratentorial high-grade gliomas; 41 had newly diagnosed tumors and 46 had recurrent tumors. Thirty of 87 patients who were treated between January 2002 and July 2013 developed CSFD. Tumor histology before BNCT and immunohistochemical staining for two molecular markers, Ki-67 and IDH1R132H, were evaluated for 20 of the 30 patients for whom pathology slides were available. Fluorescence in situ hybridization (FISH) was performed on 3 IDH1R132H-positive and 1 control IDH1R132H-negative tumors in order to determine chromosome 1p and 19q status. Histopathologic evaluation revealed that 10 of the 20 patients' tumors were IDH1R132H-negative small cell GBMs. The remaining patients had tumors consisting of other IDH1R132H-negative GBM variants, an IDH1R132H-positive GBM and two anaplastic oligodendrogliomas. Ki-67 immunopositivity ranged from 2 to 75%. In summary, IDH1R132H-negative GBMs, especially small cell GBMs, accounted for a disproportionately large number of patients who had CSF dissemination. This suggests that these tumor types had an increased propensity to disseminate via the CSF following BNCT and that these patients are at high risk for this clinically serious event.

Molecular characterization reveals NF1 deletions and FGFR1-activating mutations in a pediatric spinal oligodendroglioma.

Pediatric spinal oligodendrogliomas are rare and aggressive tumors. They do not share the same molecular features of adult oligodendroglioma, and no previous reports have examined the molecular features of pediatric spinal oligodendroglioma. We present the case of a child with a recurrent spinal anaplastic oligodendroglioma. We performed whole exome (paired tumor and germline DNA) and transcriptome (tumor RNA) sequencing, which revealed somatic mutations in NF1 and FGFR1. These data allowed us to explore potential personalized therapies for this patient and expose molecular drivers that may be involved in similar cases.

Utilization and impact of adjuvant therapy in anaplastic oligodendroglioma: an analysis on 1692 patients.

The aim of this study was to determine the utilization rates and impact of adjuvant therapy on overall survival (OS) for anaplastic oligodendroglioma (AO). Data were extracted from the National Cancer Data Base (NCDB). Chi square test, Kaplan-Meier method, and Cox regression models were employed in SPSS 22.0 (Armonk, NY: IBM Corp.) for data analyses. 1692 patients with AO who underwent surgery were identified. 945 (55.9 %) received adjuvant radiotherapy with concomitant chemotherapy (chemoRT), 102 (6.0 %) adjuvant radiotherapy (RT) sequentially followed by chemotherapy, 244 (14.4 %) adjuvant RT alone, and 401 (23.7 %) received no adjuvant therapy. Patients were more likely to receive adjuvant chemoRT if they were diagnosed in 2009-2013 vs. 2004-2008 (p < 0.001), had Karnofsky Performance Status >70 vs. <70 (p = 0.018), had private insurance vs. Medicaid vs. no insurance (p < 0.001), or had median income ≥$63,000 vs. <$63,000 (p = 0.014). Those who received adjuvant chemoRT (concomitant or sequential) had significantly better 5-year OS than those who received adjuvant RT alone or no adjuvant therapy (59.8 % vs. 65.0 % vs. 44.9 % vs. 45.6 %, p < 0.001). This significant 5-year OS benefit was also observed regardless of age. There was no difference in OS when comparing concomitant chemoRT to sequential RT and chemotherapy (p = 0.481). On multivariate analysis, receipt of adjuvant chemoRT (concomitant or sequential) remained an independent prognostic factor for improved OS. Adjuvant chemoRT (concomitant or sequential) is an independent prognostic factor for improved OS in anaplastic oligodendroglioma and should be considered for all clinically suitable patients who have undergone surgery for the disease.

High Radiation Dose to the Fornix Causes Symptomatic Radiation Necrosis in Patients with Anaplastic Oligodendroglioma.

PURPOSE: Surgery, radiotherapy (RT), and chemotherapy have prolonged the survival of patients with anaplastic oligodendroglioma. However, whether RT induces long-term toxicity remains unknown. We analyzed the relationship between the RT dose to the fornix and symptomatic radiation necrosis (SRN). MATERIALS AND METHODS: A total of 67 patients treated between 2009 and 2019 were analyzed. SRN was defined according to the following three criteria: 1) radiographic findings, 2) symptoms attributable to the lesion, and 3) treatment resulting in symptom improvement. Various contours, including the fornix, were delineated. Univariate and multivariate analyses of the relationship between RT dose and SRN, as well as receiver operating characteristic curve analysis for cut-off values, were performed. RESULTS: The most common location was the frontal lobe (n=40, 60%). Gross total resection was performed in 38 patients (57%), and 42 patients (63%) received procarbazine, lomustine, and vincristine chemotherapy. With a median follow-up of 42 months, the median overall and progression-free survival was 74 months. Sixteen patients (24%) developed SRN. In multivariate analysis, age and maximum dose to the fornix were associated with the development of SRN. The cut-off values for the maximum dose to the fornix and age were 59 Gy (equivalent dose delivered in 2 Gy fractions) and 46 years, respectively. The rate of SRN was higher in patients whose maximum dose to the fornix was >59 Gy (13% vs. 43%, p=0.005). CONCLUSION: The maximum dose to the fornix was a significant factor for SRN development. While fornix sparing may help maintain neurocognitive function, additional studies are needed.

Construction and Validation of Nomograms for Predicting Overall Survival and Cancer-Specific Survival in Patients with Primary Anaplastic Oligodendroglioma.

OBJECTIVE: Anaplastic oligodendroglioma (AOD) is a rare high-grade central nervous system tumor. The current research on prognostic prediction of AOD remains limited. This study aimed to identify prognostic factors and establish the nomograms to predict overall survival (OS) and cancer-specific survival (CSS) for patients with AOD. METHODS: Patients diagnosed with AOD between 1992 and 2020 were extracted from the Surveillance, Epidemiology, and End Result database. We performed univariate and multivariate Cox regression analyses to identify independent prognostic factors based on the training group. Kaplan-Meier survival curves were used to compare the impact of various independent factors on patient prognosis. For OS and CSS, the nomograms were constructed and verified by the validation group. Harrell''s concordance index, receiver operating characteristic curves, calibration curves, and decision curve analyses were used to assess the discrimination, consistency, and clinical value of the nomograms. RESULTS: A total of 1202 AOD patients were enrolled, being randomly divided into training (n = 841) and validation (n = 361) groups (7:3 ratio). Univariate and multivariate Cox analysis identified 4 significant independent factors (tumor site, age, surgery, and chemotherapy). For OS and CSS, Harrell''s concordance index were 0.731 (0.705-0.757) and 0.728 (0.701-0.754) in the training group, 0.688 (0.646-0.731) and 0.684 (0.639-0.729) in the validation group, respectively. Receiver operating characteristic curves and Calibration curves showed good discrimination and consistency, respectively. In addition, the decision curve analyses curves showed the nomograms have good clinical benefits. CONCLUSIONS: We successfully established the nomograms to predict the OS and CSS for AOD patients. The nomograms showed good performance in prognostic prediction, assisting clinicians in evaluating patient prognosis and personalizing treatment plans.

A rare, giant, anaplastic oligodendroglioma.

Oligodendroglioma, the third most common glioma, accounts for 5% of primary brain tumors and around 20% of all glial neoplasms. They are quite uncommon in children. Here, we aimed to show an unusual case of a 9-year-old boy developing a huge anaplastic oligodendroglioma. A high-grade astrocytoma-like supratentorial tumor was discovered by a sophisticated brain scan employing magnetic resonance imaging. The tumor was identified by histopathology as an anaplastic oligodendroglioma. Anaplastic oligodendroglioma should be considered while making the differential diagnosis of high-grade astrocytoma notwithstanding its rarity.

Anaplastic oligodendroglioma presenting with apoplectic intratumoral hemorrhage.

A 31-year-old woman presented with a headache and nausea. At presentation, her blood pressure was 114/71 mm Hg with left hemiparesis. Computed tomography revealed a large hyperdense mass in the right temporal lobe accompanied by intralesional calcifications and ventricular perforation. Spot signs were not identified, and cerebral angiography did not reveal any abnormal vasculature. The patient underwent emergency craniotomy assuming an intracerebral hemorrhage. Intraoperatively, grayish tumor tissue was found to intermingle with the clots. Microscopic findings of the tumor revealed neoplastic cells possessing perinuclear halo and cell atypia, and diffusely stained with glial fibrillary acidic protein, which were consistent with anaplastic oligodendrogliomas. However, genomic analyses of the tumor showed non-mutant isocitrate dehydrogenase 1 and telomerase reverse transcriptase, in addition to wild-type O6-methylguanine DNA-methyltransferase. These are equivalent to glioblastoma multiforme. Based on the results, we assumed that anaplastic oligodendrogliomas may develop apoplectic intratumoral hemorrhages that mimic intracerebral hemorrhage. Genomic exploration is recommended for such tumors, coupled with careful follow-up, owing to its potentially aggressive nature.

The feasibility of MRI texture analysis in distinguishing glioblastoma, anaplastic astrocytoma and anaplastic oligodendroglioma.

Background: The aim of this study was to investigate whether texture analysis-based machine learning could be utilized in presurgical differentiation of high-grade gliomas in adults. Methods: This is a single-center retrospective study involving 150 patients diagnosed with glioblastoma (GBM) (n=50), anaplastic astrocytoma (AA) (n=50) or anaplastic oligodendroglioma (AO) (n=50). The training group and validation group were randomly divided with a 4:1 ratio. Forty texture features were extracted from contrast-enhanced T1-weighted images using LIFEx software. Two feature-selection methods were separately introduced to select optimal features, including distance correlation (DC) and least absolute shrinkage and selection operator (LASSO). Optimal features selected were fed into linear discriminant analysis (LDA) classifier and support vector machine (SVM) classifier to establish multiple classification models. The performance was evaluated by using the accuracy, Kappa value and area under receiver operating characteristic curve (AUC) of each model. Results: The overall diagnostic accuracies of LDA-based models were 76.0% (DC + LDA) and 74.3% (LASSO + LDA) in the validation group, while for SVM-based models were 58.0% (DC + SVM) and 63.3% (LASSO + SVM). The combination of DC and LDA reach the highest diagnostic accuracy, AUC of GBM, AA and AO were 0.999, 0.834 and 0.865 separately, indicating that this model could distinguish GBM from AA and AO commendably, whereas the differentiation between AA and AO was relatively difficult. Conclusions: This study indicated that MRI texture analysis combined with LDA algorithm has the potential to be utilized in distinguishing the subtypes of high-grade gliomas.