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Pediatric Dermatology Mar 2020Neurothekeoma is a rare, benign, cutaneous neoplasm consisting of Schwann cells and perineural cells in myxoid stroma. Cellular neurothekeoma (CNT) was previously...
BACKGROUND/OBJECTIVES
Neurothekeoma is a rare, benign, cutaneous neoplasm consisting of Schwann cells and perineural cells in myxoid stroma. Cellular neurothekeoma (CNT) was previously thought to represent a morphologic variant of neurothekeoma, but recent studies have shown that CNTs are unrelated to neurothekeomas and are more likely of histiocytic lineage.
METHODS
Herein, we describe seven cases of CNT in pediatric patients. A comprehensive search of PubMed was performed, and 71 cases of cellular neurothekeoma in pediatric patients were reviewed.
RESULTS
The clinical differential diagnosis for these lesions included Spitz nevi, keloid, juvenile xanthogranuloma, cutaneous lymphoid hyperplasia, and lymphomatoid papulosis. All cases were treated by excision or excisional biopsy. Histopathologically, all demonstrated multilobular, primarily intradermal neoplasms composed of plump spindled or epithelioid mononuclear cells with abundant eosinophilic pale-staining cytoplasm. Immunophenotypic findings included CD68 and NKI/C3 positivity, and negative staining with cytokeratin, S-100, Melan-A, and SOX-10.
CONCLUSION
Cellular neurothekeoma is distinguished from conventional neurothekeoma by increased cellularity, a lack of myxoid stroma, and a lack of neural expression with immunohistochemical stains. These uncommon neoplasms should be included in the differential diagnosis of dermal nodules in children. Accurate diagnosis of these lesions is essential, as they can be mistaken for malignancy leading to unnecessary treatment.
Topics: Adolescent; Child; Child, Preschool; Cohort Studies; Female; Humans; Infant; Male; Neurothekeoma; Skin Neoplasms
PubMed: 31930561
DOI: 10.1111/pde.14043 -
ELife Oct 2020Several MRI measures have been proposed as in vivo biomarkers of myelin, each with applications ranging from plasticity to pathology. Despite the availability of these... (Meta-Analysis)
Meta-Analysis
Several MRI measures have been proposed as in vivo biomarkers of myelin, each with applications ranging from plasticity to pathology. Despite the availability of these myelin-sensitive modalities, specificity and sensitivity have been a matter of discussion. Debate about which MRI measure is the most suitable for quantifying myelin is still ongoing. In this study, we performed a systematic review of published quantitative validation studies to clarify how different these measures are when compared to the underlying histology. We analyzed the results from 43 studies applying meta-analysis tools, controlling for study sample size and using interactive visualization (https://neurolibre.github.io/myelin-meta-analysis). We report the overall estimates and the prediction intervals for the coefficient of determination and find that MT and relaxometry-based measures exhibit the highest correlations with myelin content. We also show which measures are, and which measures are not statistically different regarding their relationship with histology.
Topics: Animals; Biomarkers; Humans; Magnetic Resonance Imaging; Mice; Myelin Sheath; Rats
PubMed: 33084576
DOI: 10.7554/eLife.61523 -
World Neurosurgery Jun 2024Schwannomas are benign peripheral nerve sheath tumors arising from myelinating Schwann cells. Although macrocystic changes are regularly encountered in schwannoma... (Review)
Review
BACKGROUND
Schwannomas are benign peripheral nerve sheath tumors arising from myelinating Schwann cells. Although macrocystic changes are regularly encountered in schwannoma variants such as vestibular nerve tumors, they are exceedingly rare among spinal neoplasms.
METHODS
Case report and systematic review of 4 databases (Ovid Medline, PubMed, Science Direct, and SCOPUS) from inception to present. All peer-reviewed publications reporting intradural cystic thoracic schwannoma were included.
RESULTS
We identified 8 publications documenting 9 cases of cystic thoracic schwannoma. Four were female, 5 male; median age was 41 years (range, 27-80). Presentations ranged from incidental to pain, sensory changes, lower extremity paresis, or bowel/bladder dysfunction. Characteristic radiographic findings included T1 hypointensity, T2 hyperintensity, and cord effacement or compression. The present case followed a similar pattern: a 52-year-old male presented with worsening bilateral lower extremity weakness, low back pain, and gait dysfunction, worsening over 3 days. Examination also revealed decreased left lower extremity sensation. Imaging identified a well-delineated intradural, extramedullary macrocystic extending over T7-T10. The patient underwent a laminectomy resulting in complete tumor resection and restoration of intact neurologic function. Final pathology confirmed benign cystic schwannoma.
CONCLUSIONS
Macrocystic thoracic schwannomas are exceedingly rare and lack a comprehensive scheme for clinical classification of their natural history and pathogenesis. We report the 10th case of such a schwannoma, and the first associated systematic review. Although macrocystic thoracic schwannomas are not frequently encountered, accurate diagnosis and appropriate neurosurgical treatment is critical in these vulnerable patients, given the opportunity for excellent functional outcomes following neurosurgical treatment.
Topics: Humans; Neurilemmoma; Male; Middle Aged; Thoracic Vertebrae; Female; Spinal Cord Neoplasms; Adult; Aged
PubMed: 38522790
DOI: 10.1016/j.wneu.2024.03.091 -
Pathogens (Basel, Switzerland) Dec 2023is an intracellular bacillus that causes leprosy, a neglected disease that affects macrophages and Schwann cells. Leprosy reactions are acute inflammatory responses to... (Review)
Review
BACKGROUND
is an intracellular bacillus that causes leprosy, a neglected disease that affects macrophages and Schwann cells. Leprosy reactions are acute inflammatory responses to mycobacterial antigens, classified as type1 (T1R), a predominant cellular immune response, or type2 (T2R), a humoral phenomenon, leading to a high number of bacilli in infected cells and nerve structures. Xenophagy is a type of selective autophagy that targets intracellular bacteria for lysosomal degradation; however, its immune mechanisms during leprosy reactions are still unclear. This review summarizes the relationship between the autophagic process and elimination during leprosy reactions.
METHODS
Three databases, PubMed/Medline (n = 91), Scopus (n = 73), and ScienceDirect (n = 124), were searched. After applying the eligibility criteria, articles were selected for independent peer reviewers in August 2023.
RESULTS
From a total of 288 studies retrieved, eight were included. In multibacillary (MB) patients who progressed to T1R, xenophagy blockade and increased inflammasome activation were observed, with IL-1β secretion before the reactional episode occurrence. On the other hand, recent data actually observed increased IL-15 levels before the reaction began, as well as IFN-γ production and xenophagy induction.
CONCLUSION
Our search results showed a dichotomy in the T1R development and their relationship with xenophagy. No T2R studies were found.
PubMed: 38133338
DOI: 10.3390/pathogens12121455 -
The Journal of Surgical Research Dec 2021Histomorphometry quantitatively evaluates nerve regeneration. Total myelinated fiber count (TMFC) is most accurately obtained manually across full nerve cross-sections,...
BACKGROUND
Histomorphometry quantitatively evaluates nerve regeneration. Total myelinated fiber count (TMFC) is most accurately obtained manually across full nerve cross-sections, but most researchers opt for automated, sampled analysis. Few of the numerous techniques available have been validated. The goal of this study was to compare common histomorphometric methods (full manual [FM], sampled manual [SM], and sampled automatic [SA]) to determine their reliability and consistency.
MATERIAL AND METHODS
Twenty-four rats underwent sciatic nerve (SN) repair with 20mm isografts; SNs distal to the graft were analyzed. TMFC was manually determined in each full cross-section. Counts were also extrapolated from sampled fields, both manually and automatically with ImageJ software. Myelinated fiber diameter, axon diameter, and myelin sheath thickness were measured manually in full and sampled fields; G-ratio was calculated. Repeated-measures MANOVA, Spearman correlation, and Wilcoxon signed-rank tests were performed. A systematic review of histomorphometry in rat SN repair was performed to analyze the variability of techniques in the literature.
RESULTS
FM TMFC was 13,506 ± 4,217. Both sampled methods yielded significantly different TMFCs (SM:14.4 ± 13.4%, P< 0.001; SA:21.8 ± 44.7%, P = 0.037). All three methods strongly correlated with each other, especially FM and SM (r = 0.912, P< 0.001). FM fiber diameter, axon diameter, and myelin sheath thickness did not differ from SM (P = 0.493, 0.209, and 0.331, respectively). 65% of papers used sampling; 78% utilized automated or semi-automated analysis. Software, sampling, and histomorphometric parameters varied widely.
CONCLUSION
SM and SA analysis are reliable with standardized, systematic sampling. Transparency is essential to allow comparison of data; meanwhile, researchers must be cognizant of the wide variety of methodologies in the literature.
Topics: Animals; Axons; Myelin Sheath; Nerve Regeneration; Rats; Reproducibility of Results; Sciatic Nerve
PubMed: 34403855
DOI: 10.1016/j.jss.2021.06.060 -
World Journal of Gastrointestinal... Sep 2019Gastrointestinal schwannomas are slow-growing benign mesenchymal neoplasms that originate from Schwann cells of the nerve sheath of Auerbach´s plexus or less frequently...
BACKGROUND
Gastrointestinal schwannomas are slow-growing benign mesenchymal neoplasms that originate from Schwann cells of the nerve sheath of Auerbach´s plexus or less frequently from Meissner´s plexus. The main differential diagnosis of gastric schwannomas are the gastrointestinal stromal tumors (GISTs), which are classified by their immunohistochemistry. The treatment of choice for gastric schwannomas is surgery where laparoscopy plays an important role. Wedge resection, subtotal or total gastrectomy can be done. In its counterpart, esophageal schwannomas are benign tumors of the esophagus that are very uncommon since they comprise less than 2% of all esophageal tumors. The main differential diagnosis is the leiomyoma which corresponds to the most common benign esophageal tumor, followed by GIST. The treatment consists on tumoral enucleation or esophagectomy.
AIM
To review the available literature about gastrointestinal schwannomas; especially lesions from de stomach and esophagus, including diagnosis, treatment, and follow up, as well as, reporting our institutional experience.
METHODS
A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines. The following databases were used for reviewing process: PubMed, Ovid, MEDLINE, and Scopus. Only English language manuscripts were included. All gastrointestinal schwannomas specifically located in the esophagus and stomach were included. Cases that did not report long-term follow-up were excluded.
RESULTS
Gastric localization showed a higher prevalence in both, the literature review and our institution: 94.95% ( = 317) and 83% ( = 5) respectively. With a follow-up with disease-free survival greater than 36 mo in most cases: 62.01% ( = 80) 66.66% ( = 4). In both groups, the median size was > 4.1 cm. Surgical treatment is curative in most cases.
CONCLUSION
Schwannoma must be taken into account in the differential diagnosis of gastrointestinal mesenchymal tumors. It has a good prognosis, and most are benign. A disease-free survival of more than 36 mo can be achieved by surgery.
PubMed: 31558979
DOI: 10.4251/wjgo.v11.i9.750 -
NeuroImage Apr 2021Recent years have seen an increased understanding of the importance of myelination in healthy brain function and neuropsychiatric diseases. Non-invasive microstructural... (Meta-Analysis)
Meta-Analysis
Recent years have seen an increased understanding of the importance of myelination in healthy brain function and neuropsychiatric diseases. Non-invasive microstructural magnetic resonance imaging (MRI) holds the potential to expand and translate these insights to basic and clinical human research, but the sensitivity and specificity of different MR markers to myelination is a subject of debate. To consolidate current knowledge on the topic, we perform a systematic review and meta-analysis of studies that validate microstructural imaging by combining it with myelin histology. We find meta-analytic evidence for correlations between various myelin histology metrics and markers from different MRI modalities, including fractional anisotropy, radial diffusivity, macromolecular pool, magnetization transfer ratio, susceptibility and longitudinal relaxation rate, but not mean diffusivity. Meta-analytic correlation effect sizes range widely, between R = 0.26 and R = 0.82. However, formal comparisons between MRI-based myelin markers are limited by methodological variability, inconsistent reporting and potential for publication bias, thus preventing the establishment of a single most sensitive strategy to measure myelin with MRI. To facilitate further progress, we provide a detailed characterisation of the evaluated studies as an online resource. We also share a set of 12 recommendations for future studies validating putative MR-based myelin markers and deploying them in vivo in humans.
Topics: Brain; Humans; Magnetic Resonance Imaging; Myelin Proteins; Myelin Sheath; Qualitative Research; Reproducibility of Results
PubMed: 33524576
DOI: 10.1016/j.neuroimage.2021.117744 -
European Archives of... Mar 2024Cerebral venous sinus thrombosis (CVST) is a potentially serious complication following surgical treatment of vestibular schwannoma, a benign tumor originating from... (Review)
Review
PURPOSE
Cerebral venous sinus thrombosis (CVST) is a potentially serious complication following surgical treatment of vestibular schwannoma, a benign tumor originating from Schwann cells of the vestibulocochlear nerve. This study aimed to determine the prevalence of CVST following surgical treatment of vestibular schwannoma and the factors contributing to its occurrence.
METHOD
Two independent researchers searched the global databases of PubMed, Web of Science, Scopus, and the Cochrane Library up to September 01, 2023. We employed a random-effects model for data analysis. Heterogeneity was evaluated using the I test. To assess the quality of the studies meeting our inclusion criteria, we employed the Joanna Briggs Institute Critical Appraisal Checklist.
RESULTS
We included 23 articles in this meta-analysis. The pooled prevalence of CVST after vestibular schwannoma surgery was 6.4% (95%CI 3.4-11.5%). The pooled prevalence of CVST following the retrosigmoid (RS), translabyrinthine (TL), and middle cranial fossa (MCF) approaches was 4.8% (95%CI 2.0-11.0%), 9.6% (95%CI 4.3-20.3%) and 9.9% (95%CI 1.6-42.2%), respectively, revealing a significant difference between the TL and the RS approaches (Odds ratio = 2.10, 95%CI 1.45-3.04, P < 0.001). The sigmoid sinus exhibited the highest post-operative thrombosis rate (7.9%), surpassing the transverse sinus (3.7%) and involvement of both sigmoid and transverse sinuses (1.6%), respectively. No significant associations were found with demographic or surgical factors.
CONCLUSION
In the current meta-analysis, we identified a 6.4% CVST prevalence following vestibular schwannoma surgery, with varying rates depending on the surgical approach. No significant associations with patient or surgical factors were found, emphasizing the need for heightened clinical vigilance and further research in this context.
TRAIL REGISTRATION
PROSPERO ID: CRD42023453513.
PubMed: 38443628
DOI: 10.1007/s00405-024-08534-y -
Asian Journal of Andrology 2020Peripheral nerve damage, such as that found after surgery or trauma, is a substantial clinical challenge. Much research continues in attempts to improve outcomes after...
Peripheral nerve damage, such as that found after surgery or trauma, is a substantial clinical challenge. Much research continues in attempts to improve outcomes after peripheral nerve damage and to promote nerve repair after injury. In recent years, low-intensity pulsed ultrasound (LIPUS) has been studied as a potential method of stimulating peripheral nerve regeneration. In this review, the physiology of peripheral nerve regeneration is reviewed, and the experiments employing LIPUS to improve peripheral nerve regeneration are discussed. Application of LIPUS following nerve surgery may promote nerve regeneration and improve functional outcomes through a variety of proposed mechanisms. These include an increase of neurotrophic factors, Schwann cell (SC) activation, cellular signaling activations, and induction of mitosis. We searched PubMed for articles related to these topics in both in vitro and in vivo animal research models. We found numerous studies, suggesting that LIPUS following nerve surgery promotes nerve regeneration and improves functional outcomes. Based on these findings, LIPUS could be a novel and valuable treatment for nerve injury-induced erectile dysfunction.
Topics: Animals; Cell Proliferation; Cell Survival; Erectile Dysfunction; Humans; Male; Mitosis; Nerve Growth Factors; Nerve Regeneration; Penis; Peripheral Nerve Injuries; Pudendal Nerve; Schwann Cells; Signal Transduction; Ultrasonic Therapy; Ultrasonic Waves
PubMed: 31535626
DOI: 10.4103/aja.aja_95_19 -
World Journal of Surgical Oncology Sep 2020Ganglioneuromas (GNs) are extremely rare, slowly growing, benign tumors that can arise from Schwann cells, ganglion cells, and neuronal or fibrous tissues. Due to their...
BACKGROUND
Ganglioneuromas (GNs) are extremely rare, slowly growing, benign tumors that can arise from Schwann cells, ganglion cells, and neuronal or fibrous tissues. Due to their origin from the sympathetic neural crest, they show neuroendocrine potential; however, most are reported to be hormonally inactive. Nevertheless, complete surgical removal is recommended for symptom control or for the prevention of potential malignant degeneration.
CASE REPORT
A 30-year-old female was referred to our oncologic center due to a giant retroperitoneal and mediastinal mass detected in computed tomography (CT) scans. The initial symptoms were transient nausea, diarrhea, and crampy abdominal pain. There was a positive family history including 5 first- and second-degree relatives. Presurgical biopsy revealed a benign ganglioneuroma. Total resection (TR) of a 35 × 25 × 25 cm, 2550-g tumor was obtained successfully via laparotomy combined with thoracotomy and partial incision of the diaphragm. Histopathological analysis confirmed the diagnosis. Surgically challenging aspects were the bilateral tumor invasion from the retroperitoneum into the mediastinum through the aortic hiatus with the need of a bilateral 2-cavity procedure, as well as the tumor-related displacement of the abdominal aorta, the mesenteric vessels, and the inferior vena cava. Due to their anatomic course through the tumor mass, the lumbar aortic vessels needed to be partially resected. Postoperative functioning was excellent without any sign of neurologic deficit.
CONCLUSION
Here, we present the largest case of a TR of a GN with retroperitoneal and mediastinal expansion. On review of the literature, this is the largest reported GN resected and was performed safely. Additionally, we present the first systematic literature review for large GN (> 10 cm) as well as for resected tumors growing from the abdominal cavity into the thoracic cavity.
Topics: Adult; Female; Ganglioneuroma; Humans; Mediastinal Neoplasms; Prognosis; Retroperitoneal Neoplasms; Retroperitoneal Space; Tomography, X-Ray Computed
PubMed: 32948207
DOI: 10.1186/s12957-020-02016-1