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Abstract Lipoblastoma/lipoblastomatosis presents some unique diagnostic and therapeutic challenges when encountered in the oral cavity. In these rare cases, diagnostic confirmation with molecular testing and a conservative surgical resection can contribute to successful management.

The manuscript describes an unusual vascular anomaly. Persistence of carotid-vertebrobasilar anastomosis is a rare occurrence with presence of bilateral hypoglossal arteries (HAs) rarer still. We present a case of bilateral persistent HAs with hypoplastic vertebral arteries which end into posterior inferior cerebellar arteries. The computed tomography and magnetic resonance imaging appearance, course, and other associations are discussed. A review of 6 cases of bilateral HA published in the world literature is also discussed. Keywords: Persistent hypoglossal artery, Computed tomography

Introduction: Inverting papillomas (IPs) represent the most common benign neoplasm of the sinonasal cavity and are known for local invasion, proclivity for recurrence, and risk of malignant transformation. IP of the temporal bone (TBIP) is exceptionally rare, with 32 reported cases. We present a new case of multifocal IP of the sinonasal cavity and temporal bone. Methods: Case report and review of the literature. Results: A 45-year-old man presented with a left sided biopsy proven IP and associated left sided hearing loss. Imaging demonstrated a left sided nasal mass and a separate non-contiguous soft tissue mass filling the left middle ear without involvement of the eustachian tube. He underwent an endonasal endoscopic gross total resection of the sinonasal lesion and biopsy of the middle ear mass with pathology showing IP. He subsequently underwent a left sided transtemporal resection of the TBIP. Review of the literature, revealed 32 TBIP cases, with 59% having history of associated sinonasal IP and 41% with isolated temporal bone disease. Over half of the patients demonstrated recurrence. In comparison to patients with history of sinonasal IP, isolated TBIP occurred in younger patients, was more common in females, and had less association with HPV and malignant transformation. Conclusion: TBIP is extraordinarily rare and usually presents with a history of sinonasal IP. Isolated TBIP may be a distinctly different disease process. Disease recurrence is common and risk of malignant transformation is present, so aggressive initial surgical treatment with gross total resection is advocated.

Abstract Objectives To describe the work-up and surgical management of an osteoblastoma involving the lateral skull base. Typically occurring in the spine or long bones, osteoblastomas of the craniofacial skeleton are exceedingly rare and infrequently reported. A review of the current literature regarding temporal bone osteoblastoma, diagnosis, and treatment is described. Methods This case report describes the clinical presentation, radiographic studies, surgical management, histology, and postoperative follow-up of a young man presenting to a tertiary care neurotology practice with osteoblastoma involving the lateral skull base. A review of the current literature regarding osteoblastoma of the skull base, work-up, and treatment is described. Results A 15-year-old adolescent boy with a greater than 1-year history of right-sided retroauricular pain, a palpable postauricular mass, and chronic headaches presented for evaluation/management. Microscope examination of the ears, hearing, and cranial nerve function were normal. High-resolution temporal bone computed tomography and magnetic resonance imaging scans were obtained, which revealed an expansile mass involving the junction of the temporal and occipital bones. The patient underwent a combined retrosigmoid/retrolabyrinthine resection of this extradural tumor. Histology revealed a benign bone neoplasm consistent with osteoblastoma. Complete surgical resection was achieved, and the patient's symptoms fully resolved. Follow-up imaging studies found no evidence of recurrence. The scientific literature relevant to work-up and management of osteoblastoma is reviewed. Discussion Osteoblastomas of the lateral skull base are rare, histologically benign tumors that can present with radiographic features suggestive of malignancy. An en bloc resection is important for both diagnosis and definitive treatment of these neoplasms. The differential diagnosis on imaging and histology is discussed.

Breast, lung, and prostate cancers are the three most common malignancies to metastasize to the temporal bone. Still, metastatic prostate cancer of the temporal bone is a rare finding, with approximately 21 cases reported in the literature and only 2 cases discovered more than 10 years after initial treatment of the primary. This disease may be asymptomatic and discovered incidentally; however, hearing loss, otalgia, cranial nerve palsies, and visual changes can all be presenting symptoms. We present the case of a 95-year-old man with history of primary prostate cancer treated 12 years earlier that was seen for new-onset asymmetric hearing loss and otalgia. The tympanic membranes and middle ears were normal; however, based on radiologic findings and eventual biopsy, the patient was diagnosed with extensive metastatic prostate cancer to the left temporal bone. This case (1) demonstrates that a high index of suspicion for unusual etiologies of seemingly benign symptoms must be maintained in elderly patients having prior history of cancer and (2) substantiates the value of temporal bone imaging when diagnosis may be unclear from history and physical exam.

PURPOSE: The study aims to assess the tolerance of elderly patients (70 years or older) with locally advanced rectal cancers to image-guided radiotherapy (IGRT). A retrospective review of 13 elderly patients with locally advanced rectal cancer who underwent preoperative chemoradiation using IGRT was performed. Grade 3-4 acute toxicities, survival, and long-term complications were compared to 17 younger patients (

We recently described new pathogenic variants in VRK1, in patients affected with distal Hereditary Motor Neuropathy associated with upper motor neurons signs. Specifically, we provided evidences that hiPSC-derived Motor Neurons (hiPSC-MN) from these patients display Cajal Bodies (CBs) disassembly and defects in neurite outgrowth and branching. We here focused on the Axonal Initial Segment (AIS) and the related firing properties of hiPSC-MNs from these patients. We found that the patient's Action Potential (AP) was smaller in amplitude, larger in duration, and displayed a more depolarized threshold while the firing patterns were not altered. These alterations were accompanied by a decrease in the AIS length measured in patients' hiPSC-MNs. These data indicate that mutations in VRK1 impact the AP waveform and the AIS organization in MNs and may ultimately lead to the related motor neuron disease., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Distal hereditary motor neuropathies (dHMNs) are a heterogeneous group of diseases, resembling Charcot-Marie-Tooth syndromes, but characterized by an exclusive involvement of the motor part of the peripheral nervous system. Here, we describe two new compound heterozygous mutations in VRK1, the vaccinia-related kinase 1 gene, in two siblings from a Lebanese family, affected with dHMN associated with upper motor neurons (MNs) signs. The mutations lead to severely reduced levels of VRK1 by impairing its stability, and to a shift of nuclear VRK1 to cytoplasm. Depletion of VRK1 from the nucleus alters the dynamics of coilin, a phosphorylation target of VRK1, by reducing its stability through increased proteasomal degradation. In human-induced pluripotent stem cell-derived MNs from patients, we demonstrate that this drop in VRK1 levels leads to Cajal bodies (CBs) disassembly and to defects in neurite outgrowth and branching. Mutations in VRK1 have been previously reported in several neurological diseases affecting lower or both upper and lower MNs. Here, we describe a new phenotype linked to VRK1 mutations, presenting as a classical slowly progressive motor neuropathy, beginning in the second decade of life, with associated upper MN signs. We provide, for the first time, evidence for a role of VRK1 in regulating CB assembly in MNs. The observed MN defects are consistent with a length dependent axonopathy affecting lower and upper MNs, and we propose that diseases due to mutations in VRK1 should be grouped under a unique entity named `VRK1-related motor neuron disease'., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Spinal muscular atrophy (SMA) is caused by mutations and/or deletions of the survival motor neuron gene ( SMN1 ). Besides its function in the biogenesis of spliceosomal snRNPs, SMN might possess a motor neuron specific role and could function in the transport of axonal mRNAs and in the modulation of local protein translation. Accordingly, SMN colocalizes with axonal mRNAs of differentiated NSC-34 motor neuron-like cells. We recently showed that SMN depletion gives rise to a decrease in the axonal transport of the mRNAs encoding Annexin A2 (Anxa2). In this work, we have characterized the structural features of the Anxa2 mRNA required for its axonal targeting by SMN. We found that a G-rich motif located near the 3'UTR is essential for axonal localization of the Anxa2 transcript. We also show that mutations in the motif sequence abolish targeting of Anxa2 reporter mRNAs in axon-like structures of differentiated NSC-34 cells. Finally, localization of both wild-type and mutated Anxa2 reporters is restricted to the cell body in SMN-depleted cells. Altogether, our studies show that this G-motif represents a novel and essential determinant for axonal localization of the Anxa2 mRNA mediated by the SMN complex., (© 2017 Rihan et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.)

Spinal muscular atrophy is a neuromuscular disease resulting from mutations in the SMN1 gene, which encodes the survival motor neuron (SMN) protein. SMN is part of a large complex that is essential for the biogenesis of spliceosomal small nuclear RNPs. SMN also colocalizes with mRNAs in granules that are actively transported in neuronal processes, supporting the hypothesis that SMN is involved in axonal trafficking of mRNPs. Here, we have performed a genome-wide analysis of RNAs present in complexes containing the SMN protein and identified more than 200 mRNAs associated with SMN in differentiated NSC-34 motor neuron-like cells. Remarkably, ~30% are described to localize in axons of different neuron types. In situ hybridization and immuno-fluorescence experiments performed on several candidates indicate that these mRNAs colocalize with the SMN protein in neurites and axons of differentiated NSC-34 cells. Moreover, they localize in cell processes in an SMN-dependent manner. Thus, low SMN levels might result in localization deficiencies of mRNAs required for axonogenesis.