Nerve Sheath Tumors Research Articles

The Combined Use of Acute Regional and Interventional Pain Offers Superior Quality of Life in Palliative Care

BACKGROUND: Pain is a common symptom associated with cancer and can greatly compromise quality of life, motivation, and further treatments. Intrathecal pump (ITP) offers improved pain scores and clinical outcomes, while reducing the adverse effects of systemic analgesics. CASE REPORT: A 29-year-old woman with neurofibromatosis type 1 had a malignant peripheral nerve sheath tumor in her right thigh surgically resected. However, one month later, metastatic lesions were found throughout her body. Despite chemotherapy, the disease spread and pain became severe resulting in multiple hospitalizations and halting treatment. Multimodal analgesia was pursued, including regional anesthesia, but she was unable to tolerate the adverse effects of systemic opioids. For long-term analgesia, ITP was pursued, which significantly improved her pain control and quality of life. CONCLUSIONS: In advanced stages of cancer, we highlight the significant benefits ITP offers with improved quality of life and reduced medication side-effect profiles vs systemic analgesics. KEY WORDS: Intrathecal pump, regional anesthesia, palliative care, cancer, chronic pain, opioids

A rare case presentation of neurofibromatosis type 1 with multiple gastrointestinal stromal tumors: a case report

Neurofibromatosis type 1 (NF1), a hereditary cancer predisposing syndrome is an autosomal dominant disorder. Gastrointestinal stromal tumor (GIST) is the most prevalent non-neurological tumor in these individuals. In NF1-associated GIST, KIT and platelet-derived growth factor receptor α (PDGFRA) mutations might not be present, and Imatinib may not be effective. Surgical resection is the first-line treatment. The primary aim was to include the possibility of rare tumors including GIST in neurofibromatosis patients in the differential diagnosis of GIT pathology/presentation. A 50-year-old male with neurofibromatosis came with complaints of dull aching abdominal pain and on further investigation was found to have lesions in the distal small bowel, suspicious of nerve sheath tumors, in abdominal computed tomography. A laparotomy was performed and the jejunum containing nodular lesions was resected and pathologically diagnosed as GIST. The patient was then started on Imatinib. At the 6-month follow-up, no tumor recurrence was visible. The rare and unusual location of multiple GIST in neurofibromatosis patients underscores its importance in differential diagnosis, and our case report on the patient's therapy and the clinical outcome could aid in patient care.

Role of catecholamine synthases in the maintenance of cancer stem-like cells in malignant peripheral nerve sheath tumors.

Malignant peripheral nerve sheath tumors (MPNSTs) are malignant tumors that are derived from Schwann cell lineage around peripheral nerves. As in many other cancer types, cancer stem cells (CSCs) have been identified in MPNSTs, and they are considered the cause of treatment resistance, recurrence, and metastasis. As an element defining the cancer stemness of MPNSTs, we previously reported a molecular mechanism by which exogenous adrenaline activates a core cancer stemness factor, YAP/TAZ, through β2 adrenoceptor (ADRB2). In this study, we found that MPNST cells express catecholamine synthases and that these enzymes are essential for maintaining cancer stemness, such as the ability to self-renew and maintain an undifferentiated state. Through gene knockdown and inhibition of these enzymes, we confirmed that catecholamines are indeed synthesized in MPNST cells. The results confirmed that catecholamine synthase knockdown in MPNST cells reduces the activity of YAP/TAZ. These data suggest that a mechanism of YAP/TAZ activation by de novo synthesized adrenaline, as well as exogenous adrenaline, may exist in the maintenance of cancer stemness of MPNST cells. This mechanism not only helps to understand the pathology of MPNST, but could also contribute to the development of therapeutic strategies for MPNST.

Impact of formulation on solid oxygen-entrapping materials to overcome tumor hypoxia.

Tumor hypoxia, resulting from rapid tumor growth and aberrant vascular proliferation, exacerbates tumor aggressiveness and resistance to treatments like radiation and chemotherapy. To increase tumor oxygenation, we developed solid oxygen gas-entrapping materials (O2-GeMs), which were modeled after clinical brachytherapy implants, for direct tumor implantation. The objective of this study was to investigate the impact different formulations of solid O2-GeMs have on the entrapment and delivery of oxygen. Using a Parr reactor, we fabricated solid O2-GeMs using carbohydrate-based formulations used in the confectionary industry. In evaluating solid O2-GeMs manufactured from different sugars, the sucrose-containing formulation exhibited the highest oxygen concentration at 1 mg/g, as well as the fastest dissolution rate. The addition of a surface coating to the solid O2-GeMs, especially polycaprolactone, effectively prolonged the dissolution of the solid O2-GeMs. In vivo evaluation confirmed robust insertion and positioning of O2-GeMs in a malignant peripheral nerve sheath tumor, highlighting potential clinical applications.

Primary intradural extraosseous Ewing's sarcoma of the L3 nerve root: illustrative case.

Ewing's sarcoma is an uncommon, aggressive malignancy that typically presents as an osseous lesion, most commonly in children and adolescents. Very rarely Ewing's sarcoma can present as an intradural extramedullary mass mimicking more common tumors. A 32-year-old female had a left L3 nerve root-associated lesion identified in the setting of recent-onset radiculopathy. Contrast-enhanced magnetic resonance imaging of the lumbar spine was favored to demonstrate a schwannoma or neurofibroma. Hemilaminectomy, facetectomy, and resection of the mass led to improved radiculopathy and a tissue diagnosis of Ewing's sarcoma. Immediate referral to medical oncology facilitated expeditious initiation of adjuvant chemotherapy and radiation. The differential diagnosis for newly identified nerve root-associated tumors should remain broad, including common benign pathologies and rare malignant entities. Tissue remains the gold standard for diagnosis, as preoperative imaging suggested a nerve sheath tumor. Malignant pathologies such as Ewing's sarcoma must be considered, especially in the setting of rapidly progressive symptoms or interval growth on serial imaging. Early diagnosis allows for the timely initiation of comprehensive oncological care. Long-term multidisciplinary follow-up is necessary for the surveillance of disease progression.

Systematic Characterization of the Clinical and Pathological Features of Schwannomas Harboring SH3PXD2A::HTRA1 Fusion

The understanding of schwannoma tumorigenesis has been reshaped by the recent identification of SH3PXD2A::HTRA1 fusion in 10% of intracranial/spinal schwannomas. Nonetheless, pathologic features of schwannomas harboring this fusion, as well as its prevalence outside intracranial/spinal locations, have not been characterized. We screened 215 consecutive schwannomas for their clinicopathologic characteristics and fusion status using reverse-transcriptase polymerase chain reaction (RT-PCR). Among 29 (13.5%) fusion-positive schwannomas, the most prevalent location was peripheral somatic tissue (30.7%, 19/62), followed by spinal/paraspinal (18.4%, 7/38), body cavity/deep structures (10%, 2/20), intracranial (1.3%, 1/75), and viscera (0/13). All 8 cellular, 4 microcystic/reticular, and 3 epithelioid schwannomas were fusion-negative, as were 41/42 nonschwannomatous peripheral nerve sheath tumors. Remarkably, a distinct ‘serpentine’ palisading pattern, comprising ovoid/plump cells shorter than usual schwannian cells in a hyalinized stroma, was identified in most fusion-positive cases and the schwannomatous component of the only fusion-positive malignant peripheral nerve sheath tumor. To validate this finding, 60 additional cases were collected, including 36 with (≥10% arbitrarily) and 24 without appreciable serpentine histology, of which 29 (80.6%) and 2 (8.3%) harbored the fusion, respectively. With percentages of ‘serpentine’ areas scored, 10% was determined as the optimal practical cut-off to predict the fusion status (sensitivity, 0.950; specificity, 0.943). Fusion positivity was significantly associated with serpentine histology, smaller tumors, younger patients, and peripheral somatic tissue, while multivariate logistic linear regression analysis only identified serpentine histology and location as independent fusion-predicting factors. RNA in situ hybridization successfully detected the fusion junction, highly concordant with RT-PCR results. Gene expression profiling on 18 schwannomas demonstrated segregation largely consistent with fusion status. Fusion-positive cases expressed significantly higher HTRA1 mRNA abundance, perhaps exploitable as a biomarker. In summary, we systematically characterize a series of 60 SH3PXD2A::HTRA1 fusion-positive schwannomas, showing their distinctive morphology and location-specific prevalence for the first time.

Deciphering the Immune Microenvironment of NF1-associated Peripheral Nerve Sheath Tumors: Identifying Early Biomarkers of Disease Progression and Malignant Transformation

Background/Objective:Neurofibromatosis type 1 (NF1) is a multisystem disorder that affects ~1/3000 newborns. Plexiform neurofibromas (PN) are present in about half of cases and can transform (lifetime risk of 8-13%) into malignant peripheral nerve sheath tumor (MPNST), a highly aggressive and metastatic sarcoma with poor survival. Unfortunately, there are currently no reliable biomarkers to identify PN at risk of undergoing malignant transformation. Our research has revealed that a subset of benign-appearing and atypical PN exhibit deregulated immune surveillance and T-cell infiltration that precede malignant transformation. In this study, we are analyzing tumor microenvironment and immune landscape in NF1-related tissue specimens to identify biomarkers of disease progression. To power these studies, this project focused on constructing a dataset of NF1-related samples to be analyzed.
 Methods:701 patients were identified via Cerner billing codes and pathology archives. De-identified clinical data, including presenting symptoms, relevant clinical history, pathology diagnoses, disease features, prior chemotherapeutics/radiation, prior gene profiling, and imaging features were collected.
 Results: We selected 86 patients with a total of 175 samples. 81% of patients had a clinical diagnosis of NF1, and 6% had a history of MPNST. Out of the 175 samples, 54 were in the head and neck, 42 in the thorax, 28 in the lower extremity, 27 in the upper extremity, 26 in the pelvis/abdomen, and 15 in the paraspinal region. The leading causes of procedures were pain (41%), growth (40%), and concern for malignancy (27%). The most common tissue diagnoses were neurofibroma (51.4%), PN (20%), and undefined-grade MPNST (11%). Out of the 46 MPNSTs, 30 were primary tumors, 4 metastases, and 12 local recurrences.
 Conclusion and Potential Impact:The results of this study will provide valuable insights to inform preclinical models of NF1-tumorigenesis to validate these findings and identify novel treatment approaches for individuals affected by these rare but devastating tumors.

Management of head & neck sarcomas in adults: A retrospective study

The research purpose is to review the surgical approach and evaluate the results in adult patients with head and neck sarcomas.The histopathology varied, including two leiomyosarcomas, six malignant fibrous histiocytomas, two malignant peripheral nerve sheath tumors, four dermatofibrosarcomas protuberans, three osteosarcomas, two angiosarcomas, one liposarcoma, one Ewing sarcoma, one synovial sarcoma, two unclassified/non-differentiated sarcomas and one solitary fibrous tumor. Surgical resection included maxillectomy, mandibulectomy, craniectomy, parotidectomy, scalp resection, face skin resection and laminectomy. The reconstruction was performed with one rectus abdominis flap, four radial forearm flaps, two latissimus dorsi flaps, two vascularized fibula flaps, two pectoralis major myocutaneous flaps, two trapezius flaps, two temporalis flaps, seven scalp flaps and two nasolabial flaps.The total patient number was 24. The hospitalization was uncomplicated, followed by postoperative radiotherapy in the majority of cases. In a mean 15-year follow-up period, 11 patients are still alive and disease-free. There were four recurrences treated with palliative radiotherapy.The surgical approach for head and neck sarcomas, including the achievement of a functionally acceptable result by organ sparing techniques, remains challenging. Wide resection combined with the appropriate reconstruction, particularly with microsurgical techniques, and followed by adjuvant radiotherapy or chemotherapy offer improved prognosis and quality of life.

Survival outcomes of malignant peripheral nerve sheath tumors (MPNSTs) with and without neurofibromatosis type I (NF1): a meta-analysis

IntroductionMalignant peripheral nerve sheath tumors (MPNSTs) are malignancies that demonstrate nerve sheath differentiation in the peripheral nervous system. They can occur sporadically or be associated with neurofibromatosis type 1 (NF1), an autosomal dominant neurocutaneous disorder, with up to 13% of patients developing MPNSTs in their lifetimes. Previous studies have suggested conflicting findings regarding the prognosis of NF1 for patients with MPNSTs. The elucidation of NF1 as an independent prognostic factor on mortality has implications for clinical management. We aim to investigate the role of NF1 status as an independent prognostic factor of overall survival (OS) and disease-specific survival (DSS) in MPNSTs.MethodsAn electronic literature search of PubMed and MEDLINE was performed on studies reporting OS or DSS outcomes of MPNSTs with and without NF1. A grey literature search by reviewing bibliographies of included studies and review articles was performed to find pertinent studies. Data was extracted and assessed in accordance with the PRISMA guidelines. A meta-analysis was performed to calculate hazard ratios (HRs) using a random-effects model. The primary and secondary outcomes were all-cause and disease-specific mortality, respectively, with NF1 as an independent prognostic factor of interest.ResultsA total of 59 retrospective studies involving 3602 patients fulfilled the inclusion criteria for OS analysis, and 23 studies involving 704 MPNST patients were included to evaluate DSS outcomes. There was a significant increase in the hazard of all-cause mortality (HR 1.63, 95% CI 1.45 to 1.84) and disease-specific mortality (HR 1.52, 95% CI 1.24 to 1.88) among NF1 as compared to sporadic cases. Subgroup analyses and meta-regression showed that this result was consistent regardless of the quality of the study and year of publication.ConclusionNF1 is associated with a substantially higher risk of all-cause and disease-specific mortality. This finding suggests that closer surveillance is required for NF1 patients at risk of developing MPNSTs.

Vesicourachal Diverticulum: An Uncommon Incidental Finding on Staging 18F-FDG PET/CT in a Patient with Suspected Malignant Transformation of Neurofibromatosis.

In a 32-y-old man with neurofibromatosis type 1, 18F-FDG PET/CT incidentally revealed a vesicourachal diverticulum, a rare anatomic variant. The PET/CT, performed for staging a malignant peripheral nerve sheath tumor, highlighted a distinctive 18F-FDG-avid pattern crucial for accurate diagnosis. Recognizing such features enhances disease assessment and clarifies distinctions between benign urogenital anomalies and malignancies in 18F-FDG PET/CT staging.

Clinical case of surgical treatment of a malignant tumor from the sheaths of peripheral nerves of retroperitoneal localization

Clinical case. The article presents a clinical case of malignant retroperitoneal schwannoma, which was a diagnostic finding. The clinical picture of the disease was dominated by pain in the lower abdomen and lower back, frequent urination. After a diagnostic examination and preliminary preparation, the patient was operated on in a hospital at the oncogynecology department of the Tashkent City branch of the Republican Specialized Scientific and practical Medical Center of Oncology and Radiology with a preliminary diagnosis of an ovarian tumor. Interrooperatively, a tumor of the retroperitoneal space with lesions of the obturator nerve was revealed. Subsequently, immunohistochemical analysis clarified the histological type of the tumor, which turned out to be a malignant schwannoma of the retroperitoneal space.Conclusion. These data may help in the management of patients with this pathology and improve the diagnosis of patients with small pelvic tumors.

Y-Box Binding Protein 1: Unraveling the Multifaceted Role in Cancer Development and Therapeutic Potential.

Y-box binding protein 1 (YBX1), a member of the Cold Shock Domain protein family, is overexpressed in various human cancers and is recognized as an oncogenic gene associated with poor prognosis. YBX1's functional diversity arises from its capacity to interact with a broad range of DNA and RNA molecules, implicating its involvement in diverse cellular processes. Independent investigations have unveiled specific facets of YBX1's contribution to cancer development. This comprehensive review elucidates YBX1's multifaceted role in cancer across cancer hallmarks, both in cancer cell itself and the tumor microenvironment. Based on this, we proposed YBX1 as a potential target for cancer treatment. Notably, ongoing clinical trials addressing YBX1 as a target in breast cancer and lung cancer have showcased its promise for cancer therapy. The ramp up in in vitro research on targeting YBX1 compounds also underscores its growing appeal. Moreover, the emerging role of YBX1 as a neural input is also proposed where the high level of YBX1 was strongly associated with nerve cancer and neurodegenerative diseases. This review also summarized the up-to-date advanced research on the involvement of YBX1 in pancreatic cancer.

Malignant peripheral nerve sheath tumor (MPNST) and MPNST-like entities are defined by a specific DNA methylation profile in pediatric and juvenile population

BackgroundMalignant peripheral nerve sheath tumors (MPNSTs) account for 3–10% of pediatric sarcomas, 50% of which occur in neurofibromatosis type 1 (NF1). Sporadic MPNSTs diagnosis may be challenging due to the absence of specific markers, apart from immunohistochemical H3K27me3 loss. DNA methylation (DNAm) profiling is a useful tool for brain and mesenchymal neoplasms categorization, and MPNSTs exhibit a specific DNAm signature. An MPNST-like group has recently been recognized, including pediatric tumors with retained H3K27me3 mark and clinical/histological features not yet well explored. This study aims to characterize the DNAm profile of pediatric/juvenile MPNSTs/MPNST-like entities and its diagnostic/prognostic relevance.ResultsWe studied 42 tumors from two groups. Group 1 included 32 tumors histologically diagnosed as atypical neurofibroma (ANF) (N = 5) or MPNST (N = 27); group 2 comprised 10 tumors classified as MPNST-like according to Heidelberg sarcoma classifier. We performed further immunohistochemical and molecular tests to reach an integrated diagnosis. In group 1, DNAm profiling was inconclusive for ANF; while, it confirmed the original diagnosis in 12/27 MPNSTs, all occurring in NF1 patients. Five/27 MPNSTs were classified as MPNST-like: Integrated diagnosis confirmed MPNST identity for 3 cases; while, the immunophenotype supported the change to high-grade undifferentiated spindle cell sarcoma in 2 samples. The remaining 10/27 MPNSTs variably classified as schwannoma, osteosarcoma, BCOR-altered sarcoma, rhabdomyosarcoma (RMS)-MYOD1 mutant, RMS-like, and embryonal RMS or did not match with any defined entity. Molecular analysis and histologic review confirmed the diagnoses of BCOR, RMS-MYOD1 mutant, DICER1-syndrome and ERMS. Group 2 samples included 5 high-grade undifferentiated sarcomas/MPNSTs and 5 low-grade mesenchymal neoplasms. Two high-grade and 4 low-grade lesions harbored tyrosine kinase (TRK) gene fusions.By HDBSCAN clustering analysis of the whole cohort we identified two clusters mainly distinguished by H3K27me3 epigenetic signature. Exploring the copy number variation, high-grade tumors showed frequent chromosomal aberrations and CDKN2A/B loss significantly impacted on survival in the MPNSTs cohort.ConclusionDNAm profiling is a useful tool in diagnostic work-up of MPNSTs. Its application in a retrospective series collected during pre-molecular era contributed to classify morphologic mimics. The methylation group MPNST-like is a ‘hybrid’ category in pediatrics including high-grade and low-grade tumors mainly characterized by TRK alterations.

P28 Congenital Cellular Plexiform Schwannoma Masquerading as Infantile Haemangioma – A Case Report

Abstract Introduction Schwannomas are tumours of the peripheral nerve sheath that rarely metastasize but are prone to recurrence. They sometimes occur in the context of syndromes such as neurofibromatosis type 2, Carney complex, and schwannomatosis. Congenital schwannomas appear as an erythematous patch that increases in size in the first few weeks and can be easily mistaken for infantile haemangioma (IH). Case A 3-month-old boy was referred to us for suspected IH on the dorsum of his right hand. At birth, he had a slightly erythematous patch but was rapidly increasing in size. Initial ultrasound done locally suggested it may be an IH based on the demonstration of arterial and venous flows. He was otherwise well, and there were no concerns about his growth or development. On examination, he had a firm mass, measuring 3 cm in diameter, that was not clinically in keeping with a vascular anomaly. Our repeated ultrasound showed a solid tumour, possibly fibrosarcoma or myofibroma. Biopsy confirmed cellular plexiform schwannoma and he underwent excision. The results of whole genome sequencing are pending (SMARC-1 and NF), and he remains under the care of the oncology team. Conclusion Clinicians assessing infants with “haemangiomas” have a difficult task of differentiating them from other soft tissue tumours. The clinical appearance of vascularity, along with high vascular flow seen on the imaging, cannot always rule out soft tissue tumours. Assessment of firmness can be somewhat subjective, but any vascular lesion that is very firm should be investigated further.

Coincidence of chronic rhinosinusitis with nasal polyps and neurofibroma

Background: Nasal polyps are painless inflammatory lesions originated from around the middlemeatus or paranasal sinus cavity; while neurofibroma is benign peripheral nerve sheath tumor. Purpose:To report a rare case of neurofibroma concurrently with nasal polyps in chronic rhinosinusitis. Casereport: A 64-year-old female with chief complaint congestion on the right nose cavity. There was a mass on both nasal cavities. Patient diagnosed with benign mass at right nasal cavity and chronic rhinosinusitis with nasal polyps at left nasal cavity; with a differential diagnosis of chronic rhinosinusitis with bilateral nasal polyps. Computer tomography scan results showed homogeneous isodense lesion in the right nasal cavity, and mucosal thickening in left nasal cavity and maxillary sinus. Patient was managed with total extirpation of the bilateral nasal cavity mass and functional endoscopic sinus surgery. Pathological examination revealed neurofibroma in the right nasal cavity and polyps in the left nasal cavity. Clinical question: “How to differentiate inflammation with tumor of nasal and paranasal sinuses? Is there a causal relationship?” Review method: Literature searching was performed with the keywords “nasal cavity neurofibroma”, AND “nasal polyps”, AND ”chronic rhinosinusitis” through database Google Scholar, PubMed, and hand searching/e-book. Result: There were 11 literatures published in the last 5 years, and 7 articles relevant with the subject. Conclusion: Chronic rhinosinusitis with nasal polyps, along with neurofibroma on nasal cavity is a rare co-incidence, and there was no correlation between those lesions. Pathological examination is a gold standard in differentiating a definite diagnosis of neurofibromas and polyps.Keywords: nasal cavity neurofibroma, nasal polyps, chronic rhinosinusitis

Discrimination of benign, atypical, and malignant peripheral nerve sheath tumors in neurofibromatosis type 1 using diffusion-weighted MRI.

Neurofibromatosis type 1 (NF1) is associated with the development of benign (BPNST) and malignant (MPNST) peripheral nerve sheath tumors. Recently described atypical neurofibromas (ANF) are considered pre-malignant precursor lesions to MPNSTs. Previous studies indicate that diffusion-weighted magnetic resonance imaging (DW-MRI) can reliably discriminate MPNSTs from BPNSTs. We therefore investigated the diagnostic accuracy of DW-MRI for the discrimination of benign, atypical, and malignant peripheral nerve sheath tumors. In this prospective explorative single-center phase II diagnostic study, 44 NF1 patients (23 male; 30.1 ± 11.8 years) underwent DW-MRI (b-values 0-800s/mm²) at 3T. Two radiologists independently assessed mean and minimum apparent diffusion coefficients (ADCmean/min) in areas of largest tumor diameters and ADCdark in areas of lowest signal intensity by manual contouring of the tumor margins of 60 BPNSTs, 13 ANFs, and 21 MPNSTs. Follow-up of ≥ 24 months (BPNSTs) or histopathological evaluation (ANFs + MPNSTs) served as diagnostic reference standard. Diagnostic ADC-based cut-off values for discrimination of the three tumor groups were chosen to yield the highest possible specificity while maintaining a clinically acceptable sensitivity. ADC values of pre-malignant ANFs clustered between BPNSTs and MPNSTs. Best BPNST vs. ANF + MPNST discrimination was obtained using ADCdark at a cut-off value of 1.6 × 10-3 mm2/s (85.3% sensitivity, 93.3% specificity), corresponding to an AUC of 94.3% (95% confidence interval: 85.2-98.0). Regarding BPNST + ANF vs. MPNST, best discrimination was obtained using an ADCdark cut-off value of 1.4 × 10-3 mm2/s (83.3% sensitivity, 94.5% specificity). DW-MRI using ADCdark allows specific and noninvasive discrimination of benign, atypical, and malignant nerve sheath tumors in NF1.

Incidence of Malignant Peripheral Nerve Sheath Tumor in Saudi Arabia: A Registry-based Descriptive Analysis

Background: Malignant peripheral nerve sheath tumors (MPNSTs) refer to malignant tumors in the cells of the peripheral nerve or nerve sheath. This study was conducted to report the incidence and provide an overview of MPNSTs in Saudi Arabia due to the rarity and lack of studies on MPNSTs in the country. Methods: This retrospective cohort study of MPNSTs included all patients diagnosed with MPNSTs in Saudi Arabia between 2010 and 2020. The data was collected from the Saudi Cancer Registry (SCR) and was analyzed using John's Macintosh Project (JMP) statistical software. Results: Twenty-five total with 25 MPNST cases were included in this study. The annual incidence in Saudi Arabia is 0.076 per million people. Of the patients, 15 were males (60.00%), and the median age was 36 (15–47) years. In this study, all 25 cases were diagnosed based on histopathology of the primary lesions (100.00%). For the sites of the lesions, the trunk and lower limbs were the most reported sites with six cases (24.00%) each. Regarding tumor grading, the majority had an unknown grade (18 cases, 72.00%), followed by grade II (moderately differentiated) in four cases (16.00%). Lastly, for tumor extension, 12 cases (48.00%) were localized, whereas only one case (4.00%) was distally metastasized. Conclusion: This study revealed a low incidence of MPNSTs in Saudi Arabia, providing information on gender distribution, age, geographical distribution, tumor site, grading, and tumor extension.

Surgical Treatment of Malignant Peripheral Nerve Sheath Tumor of the Scalp With Intracranial and Extracranial Extension: A Rare Case Report.

Malignant peripheral nerve sheath tumors of the scalp are rare neoplasms of the peripheral nervous system. Here, we describe an unusual malignant peripheral nerve sheath tumor of the scalp in an 84-year-old Asian man. The tumor was associated with bony destruction, intracranial, and extracranial extension. Trans-arterial embolization was done twice preoperatively. En block excision was performed and the dura and soft tissue defect were reconstructed by anterolateral thigh free fasciocutaneous flap. There is no recurrence and the wound healed well during follow-up.

A Cerebral Embolism Caused by a Malignant Peripheral Nerve Sheath Tumor in a Patient with Neurofibromatosis Type 1.

A 31-year-old man with neurofibromatosis type 1 (NF-1) had undergone resection of a malignant peripheral nerve sheath tumor (MPNST) on the buttock 3 months previously. He subsequently underwent mechanical thrombectomy for a hyperacute left middle cerebral artery embolism. Histopathologically, the emboli comprised neurofilament-positive pleomorphic tumor cells with geographic necrosis and conspicuous mitosis and were identified as MPNST. The patient died of respiratory failure due to lung MPNST metastasis on day 15 of hospitalization. To our knowledge, this is the first report of a spontaneous cerebral embolism due to MPNST in a NF-1 patient.

Nerve Sheath Tumours In and Around Spine—A Series of 50 Cases

Abstract Background: Nerve sheath tumours in and around the spine, especially in the junctional zones, are a challenging endeavour for the surgeon, because of the difficulty in approaching these structures as well as their close proximity to the major vessels and nerves. Most of these tumours are benign in nature. They are usually very slow growing, and hence the tumour may be detected very late in its clinical course unless it compresses or encircles any of the major neurovascular structures early in its course. The surgical results after the excision of these tumours are excellent. Most of the patients get completely cured by prompt treatment. Here we present a series of 50 nerve sheath tumours in and around the spine operated over a period of 21 years. Materials and Methods: A retrospective study was done for 50 patients who underwent an operation for nerve sheath tumours in and around the spine, over a period of 21 years. Patient’s clinical and radiological data were extracted from the Medical Record Department (MRD) of our hospital and analysed. Results: Out of the 50 cases of nerve sheath tumours, 40 patients (80%) were of schwannoma and 10 patients (20%) were of neurofibroma. Overall, 10 patients had dumbbell tumours (neurofibroma+schwannoma). The mean age group was between 4th and 6th decade. Patients were followed up for a minimum of 1 year and a maximum of 20 years period. All of these tumours were benign except one patient who had a malignant neurofibroma of the C-8 nerve root. 15 out of 50 patients presented with paraparesis, 5 with paraplegia and another 5 with quadriparesis. All these patients had complete neurological recovery after surgical removal of the tumours. Conclusion: This case series brings out the nuances in the management of nerve sheath tumours in and around the spine and their results.