INTRODUCTION

Neurofibromatosis type 1 (NF1) is an autosomal dominantly inherited condition seen in one of 4000 live births, predisposing to peripheral and central neurofibromas. Spinal tumors are seen in 40% of cases with NF1 and only 2% will develop symptoms, and among those who develop symptoms where 33% showed intradural extramedullary location. Thoracic spinal dumbbell neurofibroma is even rarer, and cases that extend to obliterate the posterior mediastinum even more so, with the case presented being the largest in size documented to date.

A 34-year-old female presented since childhood clinical findings consistent with Neurofibromatosis Type I: generalized cafe-au-lait macules, axillary freckling, cutaneous neurofibromas, two iris Lisch nodules identified via slit lamp examination, and anterolateral bowing of the right tibia, and no known parental history of Neurofibromatosis Type I. Prior to admission, the patient presented with progressive loss of motor strength of the lower extremities, and progressive dyspnea. Work-up revealed a Thoracic Intradural Extramedullary Neurofibroma extending to the Right Posterior Mediastinum measuring 15.3 cm x 12.9 cm x 9.7 cm in the thoracic cavity compressing the right lung and bronchus. An extensive two stage surgery was contemplated involving an initial resection of the Intradural mass, with spine instrumentation for support, and subsequent resection of the mediastinal extension. However, complications from the compressing tumor: complete cord transection syndrome causing spinal autonomic dysfunction, lung and airway compromise causing prolonged intubation and difficulty in weaning from mechanical ventilatory support, extensive thrombus formation in the right jugular vein, and nosocomial infections all created compounding difficulties for the surgical technique and anesthetic plan.

Cornerstone management for dumbbell spinal neurofibromas involves their total removal. The best results are obtained in patients showing minimal neurological deficits during the preoperative period. However, little improvement may be expected from patients who develop complete transection syndrome during the postoperative period. Concurrent medical management to prepare the patients are equally important. The multi-subspecialty approach required in managing these cases entails a good balance between the disability before the surgery, anticipated outcomes, and quality of life of the patients.

Neurofibromatosis Type 1 （NF1） is an autosomal dominant hereditary neurological disorder. One of the typical manifestations of NF1 is neurofibroma, which can develop gradually over time. When the volume exceeds 100 cm², it is referred to as giant neurofibroma, representing a tumor-like proliferation of Schwann cells within the nerve fiber sheath. The Department of Otolaryngology at the Affiliated Hospital of Guangdong Medical University received a rare case involving a patient with giant neurofibromatosis affecting the maxillofacial region, neck, and chest. The patient underwent successful surgical treatment with the collaboration of various medical disciplines.
Humans ; Head and Neck Neoplasms/surgery* ; Neck ; Neurofibromatoses ; Neurofibromatosis 1/surgery* ; Thoracic Neoplasms/surgery*

Neurofibromas are benign peripheral nerve sheath tumors. It is more common in neurofibromatosis type Ⅰ. However, isolated vagal nerve neurofibroma（VNN） of the neck is extremely rare, and only a few case reports have been reported. Its etiology and pathogenesis are not clear. The diagnosis is mainly based on pathological examination and immunohistochemistry, and surgical resection is the main treatment. This study reports a rare case of giant solitary vagus neurofibroma in the neck. The patient was a 29-year-old female who was found to have a mass on the right side of the neck by physical examination, which was considered to be a vagus nerve tumor by neck ultrasound and imaging examination. The tumor was completely removed during the operation, with the size of about 10.0 cm×2.5 cm, and the patient had no special discomfort. Postoperative pathology and immunohistochemistry confirmed neurofibroma. After surgery, the patient had right vocal cord paralysis, hoarseness, choking and paroxysmal cough. After swallowing function training and voice rehabilitation treatment in the department, the patient recovered satisfactorily. There was no complication and recurrence during the follow-up of 1 year. This article reviews the literature to improve the diagnosis and treatment of solitary vagus neurofibroma in the neck by combining its medical history, imaging features, pathology and immunohistochemistry, and surgical treatment.
Humans ; Female ; Adult ; Neurofibroma ; Vagus Nerve/pathology* ; Neck ; Cranial Nerve Neoplasms

Neurofibromatosis is a systemic disorder that presents with cafe-au-lait spots, intertriginous freckling, neurofibromas, optic pathway tumors, lisch nodules, and distinct osseous lesions. We present a case of a 57-year-old Filipino female with a lifelong history of multiple bumps on the skin. Clinical, dermoscopic, and histopathologic findings confirmed our diagnosis.

A multidisciplinary approach is the cornerstone of management of Neurofibromatosis Type 1. Surgical excision can be performed on symptomatic lesions, but the recurrence can occur. In April 2020, Koselugo (selumetinib) was approved by the U.S. Food and Drug Administration (FDA) for the treatment of NF1-associated plexiform neurofibromas that are disfiguring or inoperable in children 2 years and older. The outlook for patients with NF-1 is guarded and depends on the severity of the disease, the presence of malignancy, and the extent of the deformity.

OBJECTIVE: To summarize the gene therapy strategies for neurofibromatosis type 1 (NF1) and related research progress. METHODS: The recent literature on gene therapy for NF1 at home and abroad was reviewed. The structure and function of the NF1 gene and its mutations were analyzed, and the current status as well as future prospects of the transgenic therapy and gene editing strategies were summarized. RESULTS: NF1 is an autosomal dominantly inherited tumor predisposition syndrome caused by mutations in the NF1 tumor suppressor gene, which impair the function of the neurofibromin and lead to the disease. It has complex clinical manifestations and is not yet curable. Gene therapy strategies for NF1 are still in the research and development stage. Existing studies on the transgenic therapy for NF1 have mainly focused on the construction and expression of the GTPase-activating protein-related domain in cells that lack of functional neurofibromin, confirming the feasibility of the transgenic therapy for NF1. Future research may focus on split adeno-associated virus (AAV) gene delivery, oversized AAV gene delivery, and the development of new vectors for targeted delivery of full-length NF1 cDNA. In addition, the gene editing tools of the new generation have great potential to treat monogenic genetic diseases such as NF1, but need to be further validated in terms of efficiency and safety. CONCLUSION Gene therapy, including both the transgenic therapy and gene editing, is expected to become an important new therapeutic approach for NF1 patients.
Humans ; Neurofibromatosis 1/pathology* ; Neurofibromin 1/metabolism* ; GTPase-Activating Proteins ; Mutation ; Genetic Predisposition to Disease ; Genetic Therapy

Malignant peripheral nerve sheath tumor (MPNST) is a rare neurogenic malignant tumor. MPNST has aty-pical clinical symptoms and imaging presentations, difficult diagnosis, a high degree of malignancy, and poor prognosis. It usually occurs in the trunk, approximately 20% in the head and neck, and rarely in the mouth. This paper reports a case of MPNST of the tongue. A summary of the clinical features, diagnosis, and treatment of MPNST is presented in combination with a literature review to provide a reference for the diagnosis and treatment of this disease.
Humans ; Nerve Sheath Neoplasms/pathology* ; Neurofibrosarcoma ; Tongue/pathology*

OBJECTIVE: To report on a rare case of Neurofibromatosis type 2 (NF2) manifesting as oculomotor nerve palsy and explore its genetic basis. METHODS: A patient with NF2 who had presented at Beijing Ditan Hospital Affiliated to Capital Medical University on July 10, 2021 was selected as the study subject. Cranial and spinal cord magnetic resonance imaging (MRI) was carried out on the patient and his parents. Peripheral blood samples were collected and subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: MRI revealed bilateral vestibular Schwannomas, bilateral cavernous sinus meningiomas, popliteal neurogenic tumors, and multiple subcutaneous nodules in the patient. DNA sequencing revealed that he has harbored a de novo nonsense variant of the NF2 gene, namely c.757A>T, which has replaced a codon (AAG) encoding lysine (K) at position 253 with a stop codon (TAG). This has resulted in removal of the Merlin protein encoded by the NF2 gene from position 253 onwards. The variant was not found in public databases. Bioinformatic analysis suggested that the corresponding amino acid is highly conserved. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was rated as pathogenic (PVS1+PS2+PM2_Supporting+PP3+PP4). CONCLUSION The heterozygous nonsense variant c.757A>T (p.K253*) of the NF2 gene probably underlay the disease in this patient with an early onset, atypical but severe phenotype.
Male ; Humans ; Neurofibromatosis 2/genetics* ; Genes, Neurofibromatosis 2 ; Oculomotor Nerve Diseases/genetics* ; Computational Biology ; Genomics ; Mutation

Humans ; Neurofibromatosis 1 ; Larynx ; Laryngeal Neoplasms/surgery*

A 16.5-year-old Indian female presented with secondary amenorrhoea, cubitus valgus, scoliosis and multiple lentigines on the face. Karyotyping revealed mosaic Turner syndrome (TS) with 45, X/46, X iXq. She also had multiple café-au-lait macules and axillary freckles but no neurofibroma and did not fulfil the classic criteria for diagnosis of Neurofibromatosis-1(NF1). Many of her macules were smaller than 15 mm in diameter, which might be due to her hypoestrogenic state. However, exome-sequencing found a pathologic variant consistent with NF1. She was started on daily oral estrogen, and oral progesterone for 10 days every month with close monitoring for neurofibroma and/or glioma expansion. Co-occurrence of NF1 and TS is extremely rare, TS and NF1 can both affect growth and puberty, cause different cutaneous and skeletal deformities, hypertension, vasculopathy and learning disabilities. Our case highlights the need for genetic testing in some cases with NF1 who do not strictly fulfil the NIH diagnostic criteria. We also emphasize the need for close monitoring during therapy with growth hormone, estrogen and progesterone due to the potential risk of tumour expansion in NF1.
Turner syndrome ; Neurofibromatosis 1 ; NF-1

OBJECTIVE: To explore the types of NF1 gene variants and clinical characteristics among patients with Neurofibromatosis type I (NF1). METHODS: Clinical data of 12 patients diagnosed at Ningbo Women and Children's Hospital between December 2019 and May 2022 were retrospectively analyzed. The probands and their family members were subjected to high-throughput sequencing, and candidate variants were verified by Sanger sequencing and chromosome microarray analysis. RESULTS: The 12 patients had ranged from 4 months to 27 years old, with a male-to-female ratio of 2 : 1. Cafè-au-lait spots were found in all patients. 83.3% of them also had axillary and/or inguinal freckling, 58.3% had neurofibromas, and 16.7% had congenital pseudarthrosis of the tibia. Five types of NF1 gene variants were identified in the patients, including 5 nonsense variants, 4 frameshift variants, 1 missense variant, 1 splice variant, 1 large deletion involving the whole gene. Six patients were found to harbor de novo variants, 2 had inherited the variants from their parents, and 4 were not verified for their parental origin. The c.3379del (p.Thr1127Glnfs*15) and c.6628_6629del (p.Glu2210Thrfs*10) variants were unreported in literature and databases. CONCLUSION Most NF1 patients may present with Cafè-au-lait spots initially and are due to pathogenic variant of the NF1 gene. High-throughput sequencing can efficiently identify such variants among the patients and enable the definite diagnosis.
Child ; Humans ; Female ; Male ; Neurofibromatosis 1/diagnosis* ; Cafe-au-Lait Spots/diagnosis* ; Genes, Neurofibromatosis 1 ; Retrospective Studies ; Frameshift Mutation