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  1. Home
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Browsing by Author "Vortmeyer, Alexander"

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    Cerebellopontine Angle Primary Choroid Plexus Carcinoma Present in an Adult: Case Report and Literature Review
    (Cureus, 2021-02-10) Witten, Andrew J.; Mendenhall, Stephen K.; DeWitt, Logan S.; Vortmeyer, Alexander; Cohen-Gadol, Aaron; Neurological Surgery, School of Medicine
    Choroid plexus tumors (CPTs) are rare intraventricular neoplasms that primarily occur in children and are rare in adults. Of the CPT subtypes, choroid plexus carcinomas (CPC) are highly aggressive and malignant and of World Health Organization (WHO) Grade III. Dissemination through the cerebrospinal fluid space is the inevitable natural course of the disease. In this case report, we present a 33-year-old female with a past medical history notable for schizophrenia and bipolar disease who suffered from left-sided acute vision loss and hearing loss. Magnetic resonance imaging (MRI) demonstrated multiple enhancing masses found in the left cerebellopontine angle (CPA), right internal auditory canal, the atrium of the left ventricle, and the left foramen of Monroe. After surgical decompression of the CPA tumor, the permanent final pathology was consistent with CPC. To our knowledge, this is the first reported case of a primary CPC occurring within the CPA in an adult. The unique presentation and progression of this rare adult-onset CPC provide insight for the diagnosis and treatment of other rare instances of CPTs.
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    Conjunctival Fungal Ball Mimicking Melanoma
    (Elsevier, 2020-04) Chuang, Katherine; Vortmeyer, Alexander; Liu, Shaohui; Ophthalmology, School of Medicine
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    Developmental vascular malformations in EPAS1 gain-of-function syndrome
    (American Society for Clinical Investigation, 2021-03-08) Rosenblum, Jared S.; Wang, Herui; Dmitriev, Pauline M.; Cappadona, Anthony J.; Mastorakos, Panagiotis; Xu, Chen; Jha, Abhishek; Edwards, Nancy; Donahue, Danielle R.; Munasinghe, Jeeva; Nazari, Matthew A.; Knutsen, Russell H.; Rosenblum, Bruce R.; Smirniotopoulos, James G.; Pappo, Alberto; Spetzler, Robert F.; Vortmeyer, Alexander; Gilbert, Mark R.; McGavern, Dorian B.; Chew, Emily; Kozel, Beth A.; Heiss, John D.; Zhuang, Zhengping; Pacak, Karel; Pathology and Laboratory Medicine, School of Medicine
    Mutations in EPAS1, encoding hypoxia-inducible factor-2α (HIF-2α), were previously identified in a syndrome of multiple paragangliomas, somatostatinoma, and polycythemia. HIF-2α, when dimerized with HIF-1β, acts as an angiogenic transcription factor. Patients referred to the NIH for new, recurrent, and/or metastatic paraganglioma or pheochromocytoma were confirmed for EPAS1 gain-of-function mutation; imaging was evaluated for vascular malformations. We evaluated the Epas1A529V transgenic syndrome mouse model, corresponding to the mutation initially detected in the patients (EPAS1A530V), for vascular malformations via intravital 2-photon microscopy of meningeal vessels, terminal vascular perfusion with Microfil silicate polymer and subsequent intact ex vivo 14T MRI and micro-CT, and histologic sectioning and staining of the brain and identified pathologies. Further, we evaluated retinas from corresponding developmental time points (P7, P14, and P21) and the adult dura via immunofluorescent labeling of vessels and confocal imaging. We identified a spectrum of vascular malformations in all 9 syndromic patients and in all our tested mutant mice. Patient vessels had higher variant allele frequency than adjacent normal tissue. Veins of the murine retina and intracranial dura failed to regress normally at the expected developmental time points. These findings add vascular malformation as a new clinical feature of EPAS1 gain-of-function syndrome.
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    Efficacy of pre-operative stereotactic radiosurgery followed by surgical resection and correlative radiobiological analysis for patients with 1-4 brain metastases: study protocol for a phase II trial
    (Biomed Central, 2018-12-20) Huff, Wei X.; Agrawal, Namita; Shapiro, Scott; Miller, James; Kulwin, Charles; Shah, Mitesh; Savage, Jesse J.; Payner, Troy; Vortmeyer, Alexander; Watson, Gordon; Dey, Mahua; Neurological Surgery, School of Medicine
    BACKGROUND: Stereotactic radiosurgery (SRS) has emerged as a common adjuvant modality used with surgery for resectable brain metastases (BMs). However, the optimal sequence of the multi-modality therapy has not been established. The goal of the study is to evaluate 6-month local control utilizing pre-operative SRS followed by surgical resection for patients with 1-4 brain metastases. METHODS: This prospective, single arm, phase II trial will recruit patients with up to 4 brain metastases and at least one resectable lesion. All lesions will be treated with SRS and symptomatic lesions will be resected within 1-4 days after SRS. Patients will be monitored for 6-month local control, in-brain progression free survival, distant in-brain failure, rate of leptomeningeal spread, radiation necrosis and overall survival. Additionally, we will also perform correlative radiobiological molecular studies to assess the effect of radiation dosing on the tumor tissue and clinical outcomes. We expect that pre-operative SRS to the gross tumor prior to surgical resection will improve local control and decrease leptomeningeal failure. DISCUSSION: Our study is the second prospective trial to investigate the efficacy of pre-operative SRS in the treatment of multiple BMs. In addition, the correlative molecular studies will be the first to investigate early response of BMs at a cellular and genetic level in response to radiation doses and potentially provide molecular prognostic markers for local control and overall survival.
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    Expression of Hemangioblast Proteins in von Hippel-Lindau Disease Related Tumors
    (MDPI, 2023-04-29) Vergauwen, Evelynn; Forsyth, Ramses; Vortmeyer, Alexander; Gläsker, Sven; Pathology and Laboratory Medicine, School of Medicine
    Von Hippel-Lindau (VHL) disease is a hereditary tumor syndrome that targets a highly selective subset of organs causing specific types of tumors. The biological basis for this principle of organ selectivity and tumor specificity is not well understood. VHL-associated hemangioblastomas share similar molecular and morphological features with embryonic blood and vascular precursor cells. Therefore, we suggest that VHL hemangioblastomas are derived from developmentally arrested hemangioblastic lineage keeping their potential of further differentiation. Due to these common features, it is of major interest to investigate whether VHL-associated tumors other than hemangioblastoma also share these pathways and molecular features. The expression of hemangioblast proteins has not yet been assessed in other VHL-related tumors. To gain a better understanding of VHL tumorigenesis, the expression of hemangioblastic proteins in different VHL-associated tumors was investigated. The expression of embryonic hemangioblast proteins Brachyury and TAL1 (T-cell acute lymphocytic leukemia protein 1) was assessed by immunohistochemistry staining on 75 VHL-related tumors of 51 patients: 47 hemangioblastomas, 13 clear cell renal cell carcinomas, 8 pheochromocytomas, 5 pancreatic neuroendocrine tumors, and 2 extra-adrenal paragangliomas. Brachyury and TAL1 expression was, respectively, observed in 26% and 93% of cerebellar hemangioblastomas, 55% and 95% of spinal hemangioblastomas, 23% and 92% of clear cell renal cell carcinomas, 38% and 88% of pheochromocytomas, 60% and 100% of pancreatic neuroendocrine tumors, and 50% and 100% of paragangliomas. We concluded that the expression of hemangioblast proteins in different VHL-associated tumors indicates a common embryological origin of these lesions. This may also explain the specific topographic distribution of VHL-associated tumors.
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    Head and neck paraganglioma in Pacak-Zhuang syndrome
    (Oxford University Press, 2025) Rosenblum, Jared S.; Cole, Yasemin; Dang, Danielle; Lookian, Pashayar P.; Alkaissi, Hussam; Patel, Mayank; Cappadona, Anthony J.; Jha, Abhishek; Edwards, Nancy; Donahue, Danielle R.; Munasinghe, Jeeva; Wang, Herui; Knutsen, Russell H.; Pappo, Alberto S.; Lechan, Ronald M.; Kozel, Beth A.; Smirniotopoulos, James G.; Kim, H. Jeffrey; Vortmeyer, Alexander; Miettinen, Markku; Heiss, John D.; Zhuang, Zhengping; Pacak, Karel; Pathology and Laboratory Medicine, School of Medicine
    Background: Head and neck paragangliomas (HNPGLs) are typically slow-growing, hormonally inactive tumors of parasympathetic paraganglia. Inactivation of prolyl-hydroxylase domain-containing 2 protein causing indirect gain-of-function of hypoxia-inducible factor-2α (HIF-2α), encoded by EPAS1, was recently shown to cause carotid body hyperplasia. We previously described a syndrome with multiple sympathetic paragangliomas caused by direct gain-of-function variants in EPAS1 (Pacak-Zhuang syndrome, PZS) and developed a corresponding mouse model. Methods: We evaluated a cohort of patients with PZS (n = 9) for HNPGL by positron emission tomography, magnetic resonance imaging, and computed tomography and measured carotid body size compared to literature reference values. Resected tumors were evaluated by histologic sectioning and staining. We evaluated the corresponding mouse model at multiple developmental stages (P8 and adult) for lesions of the head and neck by high resolution ex vivo imaging and performed immunohistochemical staining on histologic sections of the identified lesions. Results: hree patients had imaging consistent with HNPGL, one of which warranted resection and was confirmed on histology. Three additional patients had carotid body enlargement (Z-score > 2.0), and 3 had carotid artery malformations. We found that 9 of 10 adult variant mice had carotid body tumors and 6 of 8 had a paraganglioma on the cranio-caval vein, the murine homologue of the superior vena cava; these were also found in 4 of 5 variant mice at post-natal day 8. These tumors and the one resected from a patient were positive for tyrosine hydroxylase, synaptophysin, and chromogranin A. Brown fat in a resected patient tumor carried the EPAS1 pathogenic variant. Conclusions: These findings (1) suggest HNPGL as a feature of PZS and (2) show that these pathogenic variants are sufficient to cause the development of these tumors, which we believe represents a continuous spectrum of disease starting from hyperplasia.
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    Pediatric Prostatic Alveolar Rhabdomyosarcoma Presenting with Metastatic Spinal Cord Compression in the Thoracic Spine: A Case Report and Review of the Literature
    (Springer Nature, 2024-03-20) Perry, Matthew T.; Witten, Andrew J.; Marwan, Majeed; Vortmeyer, Alexander; Tailor, Jignesh; Neurological Surgery, School of Medicine
    Rhabdomyosarcoma (RMS) is a pediatric malignancy with a variable prognosis depending on tumor stage and genotype. There has been a significant improvement in survival rates over the past decades. However, aggressive variants can metastasize to locations that are difficult to treat. We report a case of prostatic alveolar rhabdomyosarcoma with metastases to the bone marrow and thoracic spine in a child. The patient was treated with a multimodal approach that included surgical resection of the epidural mass; the administration of vincristine, dactinomycin, and cyclophosphamide; and radiotherapy. Unfortunately, after six months, the patient showed disease progression and was started on secondary-line treatment. This case illustrates the difficulties in managing end-stage metastatic rhabdomyosarcoma and is the first report of prostatic rhabdomyosarcoma presenting with spinal cord compression in a child.
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    Predictors of Seizure Freedom in Pediatric Low-Grade Gliomas
    (Springer Nature, 2022-11-26) Budnick, Hailey C.; Baygani, Shawyon; Easwaran, Teresa; Vortmeyer, Alexander; Jea, Andrew; Desai, Virendra; Raskin, Jeffrey; Neurological Surgery, School of Medicine
    Objective: Pediatric low-grade gliomas (LGGs) are found in approximately one to three percent of patients with childhood epilepsy. Epilepsy in these patients is often medically refractory and therefore represents a unique cohort with significant morbidity from concomitant pathology. Similar studies in adult patients with low-grade gliomas have identified predictors of seizure freedom including gross-total resection, preoperative seizure control on antiepileptic medication and duration of seizures of less than one year. This study aims to identify similar predictors of seizure freedom in operatively managed pediatric LGGs. Methods: A retrospective chart review was performed for patients diagnosed with World Health Organization (WHO) Grade I and II gliomas in patients ≤18 years old at a single institution (Indiana University School of Medicine at Riley Hospital for Children in Indianapolis, IN) from 2007-2017. Infratentorial and purely intraventricular lesions were excluded. WHO classification and histologic diagnosis were based on surgical pathology. Tumor grade, location, laterality, seizure status at presentation, and AED requirements pre- and post-operatively were recorded. Chi-squared analyses for independence were performed controlling for age at presentation, resection extent, seizure type, and Engel Class for seizure freedom post-operatively. Results: Forty-two patients met the inclusion criteria. Preoperative seizures were observed in 23 patients (55%). Presentation with preoperative seizures was highly associated with continued seizure burden post-operatively, independent of the extent of surgical resection. Supratentorial location and the administration of prophylactic pre- and post-operative AEDs were associated with Engel Class I seizure freedom. Temporal location was not significantly associated with medically refractory epilepsy compared with extra-temporal locations. Conclusions: In our cohort of pediatric LGGs, we find that patients that did not initially present with seizures and those who were treated with prophylactic pre- and post-operative AEDs, were more likely to achieve Engel Class I seizure freedom post-operatively. Tumors located in the temporal location were not significantly associated with a higher seizure burden than other supratentorial, extra-temporal tumors. Neither extent of resection nor electrocorticography-guided resection correlated with improved seizure freedom outcomes during glioma resection.
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