Diffuse Leptomeningeal Glioneuronal Tumors: A Case Series of Five Patients with Parenchymal Forms and an Analysis of the Diagnostic Challenges, Treatment Options and Outcomes.

BACKGROUND: Diffuse leptomeningeal glioneuronal tumors (DL-GNT) are rare glioneuronal neoplasms with oligodendroglioma-like cells. These tumors can present as a dominant intracranial mass or as a solitary spinal cord mass without leptomeningeal involvement. In this study, we aimed to determine the magnetic resonance imaging and histopathological features, treatment modalities, and clinical outcomes of the parenchymal forms of DL-GNTs. METHODS: This is a retrospective three-center case series study of 5 patients with a confirmed parenchymal form of DLGTs, out of which 4 patients were adults. Brain and spinal cord MR imaging were performed in all patients at either 1.5 or 3T. The patients' age ranged from 5 years to 50 years with a mean age of 27.6 years at presentation. RESULTS: Four of the tumors were located in the frontal lobe, and one in the tectum. They were usually solid-cystic enhancing tumors as the other mixed neuronal-glial tumors. All of the tumors had an extension to the superficial surface of a cerebral hemisphere. One had systemic bone metastases. The clinical signs and symptoms of the parenchymal form varied based on the location of the mass, in contrast to the leptomeningeal form associated with hydrocephalus. In one case, the tumor's initial grade was defined as intermediate. The initial histopathology of the two cases was low-grade and no upgrade occurred in the follow-up period. In two cases, although the tumors were low grade initially, they progressed to an anaplastic form in the follow-up period. CONCLUSION: The parenchymal form of DL-GNTs is common in adults. Extension to the superficial surface of a cerebral hemisphere is a distinctive imaging feature. Systemic osseous metastasis may occur. Due to the presence of common histopathological features, including the biphasic composition of glial and neuronal cell elements and oligodendroglioma-like cells, a proposed classification approach might be more beneficial for the histopathological and imaging description, and management of the glioneuronal tumors with oligodendroglioma-like features.

Malignant Progression of a Superior Cerebellar Tentorium Solitary Fibrous Tumor in the Pineal Region with Intracranial Metastases: A Case Report and a Literature Review.

BACKGROUND: Pineal region solitary fibrous tumors (SFT) incorporate a histologic spectrum of rarely metastasizing mesenchymal neoplasms that include tumors formerly classified as hemangiopericytoma. CASE REPORT: Here, we describe a rare case of SFT of the pineal region in a 25-year-old man with a literature review. After the first surgery, the tumor reappeared as a local low-grade recurrence, followed by metastasis to the right parietal lobe, and then hyperacute intraparenchymal hematoma at the metastatic site, and later presentation of widespread intracranial intra-axial and extra-axial metastases during the follow-up period. Systemic metastases were not detected. The histopathological evaluation of the resected tissues confirmed the malignant progression of the tumor. CONCLUSION: The diagnosis of SFT of the pineal region through clinical and imaging features can be considerably challenging. Large size, intratumoral cystic areas, and intense contrast enhancement are the main conventional imaging characteristics of the tumor. Surgery is the first preferential treatment. All recurrent or metastatic cases were grade II or grade III tumors. Adjuvant radiotherapy should be added to surgical treatment in high-grade tumors. Gamma knife radiosurgery is a treatment option for intracranial metastases.

Magnetic Resonance Imaging of Unusual Neoplasms Related to Foramen of Luschka: A Review for Differential Diagnosis.

There are many types of neoplasms in or around the foramen of Luschka (FL), and definitive diagnosis in some cases requires knowledge of imaging findings. The uncommon and challenging neoplasms with FL involvement considered in this study are exophytic brainstem glioma, primary glioblastoma of the cerebellopontine angle (CPA), primary anaplastic ependymoma of the CPA, choroid plexus papilloma of the FL, solitary FL choroid plexus metastasis, extraskeletal myxoid chondrosarcoma of the jugular foramen, paraganglioma of the jugular foramen, exostosis of the jugular foramen, psammomatous meningioma in the lateral cerebellar medullary cistern, epidermoid tumor of the fourth ventricle, and a hypoglossal schwannoma. These neoplasms may have overlapping clinical and imaging features, but some have relatively distinct imaging features. Knowledge of the key clinical and magnetic resonance imaging features of these unusual lesions with FL involvement is important for radiologists to improve diagnostic ability and to assist the referring physician in the appropriate management of the patient.

Magnetic resonance imaging criteria for prediction of isocitrate dehydrogenase (IDH) mutation status in patients with grade II-III astrocytoma and oligodendroglioma.

BACKGROUND: IDH mutation status is an important prognostic marker for glial tumors, which is detected immunohistochemically after surgery. Since this method is invasive, easy and noninvasive magnetic resonance imaging (MRI) methods have recently been used in predicting the IDH mutation status. However, there is currently no standard MRI technique to predict IDH mutation. We analyzed the value of conventional MRI to predict IDH mutation and its effect on survival among grade II-III astrocytoma and oligodendroglioma patients. MATERIAL AND METHODS: We included WHO grade II-III astrocytoma and oligodendroglioma patients who underwent surgery at Bahcesehir University Goztepe Medical Park Hospital. All patients were analyzed according to their immunohistochemical IDH mutation status. Preoperative conventional MRI studies with respect to their location, diffusion restriction, contrast enhancement, calcification and hemorrhage on susceptibility-weighted image (SWI) or T2*- weighted imaging (T2*WI), and T2 -FLAIR mismatch properties were retrospectively assessed by a neuroradiologist. The relation between MRI characteristics and IDH mutation was analyzed using a chi-square test. The sensitivity and specificity of radiological IDH mutation were determined by ROC analysis. The impact of IDH mutation on survival was also analyzed by Kaplan-Meier tests. RESULTS: IDH mutation was found to be positive in 82.5% of tumors histopathologically and 54.4% radiologically. The sensitivity and specificity were 63.8% and 90%, respectively (Area under the curve/AUC = 0.369, p = 0.08). IDH wild gliomas were predominantly diffusion-restricted tumors. IDH mutant tumors were less likely to have contrast enhancement and had lower grades compared to the IDH wild tumors. The median survival time could not be reached and the overall survival was not related to any tumor characteristics or IDH mutation. CONCLUSIONS: Conventional MRI predicts IDH-mutation status in Grade II-III astrocytoma and oligodendroglioma. Contrast-enhancement and restricted diffusion were strongly associated with grade III astrocytoma and oligodendroglioma, IDH-wild type. Location, T2-FLAIR mismatch, and SWI did not contribute to making a decision on the IDH mutation status. There was no significant difference between the survival times of patients and their IDH status.

NK-92 cellular therapy for pediatric relapsed/refractory Ewing sarcoma.

Relapsed/refractory Ewing sarcoma prognosis is dreadful, especially for recurrences within the first 2 years after initial diagnosis. It is obvious that there is an urgent need for novel treatment strategies for this dismal situation. NK-92 is an activated NK cell line with high cytotoxicity against malignant cells. Here, we present a relapsed/refractory Ewing sarcoma case who had no response to conventional strategies and recieved intratumoral NK-92 cell injections. We observe that intratumoral injection of NK-92 is safe, has no toxicity and shows preliminary evidence of tumor response in relapsed/refractory Ewing Sarcoma.

The effect of bone mineral density on development of Schmorl's nodes in young patients.

OBJECTIVE: The aim of this study was to detect the relationship between the development of Schmorl's nodes (SNs) and bone mineral density (BMD) in young patients. METHODS: Computerized tomography (CT) images of the thoracolumbar vertebral column were retrospectively examined by two experienced radiologists for SNs. The diagnostic criterion for SN was defined as a node size larger than one-third but not more than two-thirds of the relevant vertebral endplate. Considering the eligibility criteria, a total of 74 individuals (60 males and 14 females; mean age: 24.3 years; age range: 18-40 years) with SN at the thoracolumbar vertebrae were included in the patient group, and a total of 38 age- and gender-matched individuals (30 males and 8 females; mean age: 25 years) with no evidence of SN were included in the control group. All these individuals were younger than 40 years. In the patient group, SNs were assessed in terms of the distribution of the thoracolumbar vertebrae, the location of the upper and lower endplates, and the total number of lesions. In all individuals included in the study, BMD was measured from the axial CT sections by quantitative CT and then compared between the two groups. RESULTS: The distribution of age and gender was comparable between the two groups (p=0.438). A total of 208 SNs were identified in the patient group. Of these, 92 (44%) were located at the thoracic vertebrae and 116 (56%) at the lumbar vertebrae. The mean BMD was 131.6 g/cm3 in the patient group and 140.7 g/cm3 in the control group (p=0.03). There was no significant relationship between the total number of SNs per patient and the mean BMD (p=0.156). CONCLUSION: Evidence from this study revealed that low BMD may be a predisposing factor for the development of SNs in patients younger than 40 years. LEVEL OF EVIDENCE: Level III, Diagnostic Study.

Posterior fossa astroblastoma in a child: a case report and a review of the literature.

A 4-year-old girl presented to the hospital with a progressive headache, difficulty walking, and persistent daily vomiting for 3 weeks. Papilledema was observed on fundoscopic examination. A large left cerebellovermian tumor with "bubbly" appearance was discovered. Total removal of the tumor mass was performed, and a diagnosis of low-grade astroblastoma was made. Adjuvant radiotherapy was performed due to the risk of recurrence. The patient is disease-free and has been kept on close follow-up for 6 months. The occurrence of posterior fossa astroblastoma has been rarely reported in the literature. Thus, when a "bubby" appearance enhancing cystic solid tumor is located on the cerebellar hemisphere in a child, an astroblastoma should also be included in the differential diagnosis.