French cohort of children and adolescents with neurofibromatosis type 1 and symptomatic inoperable plexiform neurofibromas: CASSIOPEA study

Surgery is a treatment option for neurofibromatosis type 1 (NF1)-related plexiform neurofibromas (PN), but complete resection is often not feasible. Real-world studies are warranted to understand disease burden, progression, and need for medical treatment in patients with inoperable PN. CASSIOPEA was a retrospective study of French pediatric patients (aged ≥3 to <18 years) presenting at a national multidisciplinary team (MDT) review with NF1 and ≥1 symptomatic, inoperable PN. Medical records were reviewed from the time of MDT review and over a follow-up period of up to 2 years. Primary objectives were to describe patient characteristics and target PN-associated therapy patterns. A secondary objective was evolution of target PN-related morbidities. Patients with prior, ongoing, or MDT recommendation of mitogen-activated protein kinase kinase (MEK) inhibitor treatment were excluded. Overall, 78 target PN were identified in 76 patients. At MDT review, median age was 8.4 years, with approximately 30% of patients aged 3-6 years. Target PN were primarily internal (77.3%), and 43.2% were progressive. Target PN location was evenly distributed. 34 target PN had documented MDT recommendations; of these, a majority (76.5%) were for non-medication management, including surveillance. At least one follow-up visit was recorded for 74 target PN. Despite initially being considered inoperable, 12.3% of patients underwent surgery for target PN. At MDT review, most (98.7%) target PN were associated with ≥1 morbidity, primarily pain (61.5%) and deformity (24.4%); severe morbidities were identified in 10.3%. Of 74 target PN with follow-up data, 89.2% were associated with ≥1 morbidity, primarily pain (60.8%) and deformity (25.7%). Of 45 target PN associated with pain, pain improved in 26.7%, was stable in 44.4%, and deteriorated in 28.9%. Deformity improved in 15.8% and remained stable in 84.2% of 19 target PN associated with deformity. None deteriorated. In this real-world study in France, NF1-PN disease burden was considerable, and a considerable proportion of patients were very young. Most patients received only supportive care without medication for target PN management. Target PN-related morbidities were frequent, heterogeneous, and generally did not improve during follow-up. These data highlight the importance of effective treatments that target PN progression and improve disease burden.

Neurofibromatosis Type 1: Diagnostic Timelines in Children

BACKGROUND AND OBJECTIVES

The neurofibromatosis 1 (NF1) diagnosis is challenging in young children without a family history of NF1. The aims of this study were to estimate diagnostic delays in children without a family history of NF1 and to examine the effects of using café au lait macules and skin fold freckling as a single diagnostic criterion.

PATIENTS AND METHODS

Retrospective, descriptive, observational study of all patients diagnosed with NF1 before the age of 18 years who were seen at our hospital. The medical records of those included were reviewed to identify the date on which the diagnostic criteria of NF1 were objectified. The patients were categorized into 2 groups: those with a known parental history of NF1 and those without. Café au lait macules and skin fold freckling were assessed as a single diagnostic criterion, and genetic evidence was considered to confirm highly suspicious cases.

RESULTS

We studied 108 patients younger than the age of 18 years with a diagnosis of NF1. Mean (SD) age at diagnosis was 3.94 (±3.8) years for the overall group, 1 year for patients with a parental history of NF1, and 4 years and 8 months for those without. Diagnosis was therefore delayed by 3 years and 8 months in patients without a family history.

CONCLUSION

Skin lesions were the first clinical manifestation of NF1 in most patients. We believe that the National Institutes of Health's diagnostic criteria for NF1 should be updated to aid diagnosis in young children.

MRI-guided laser interstitial thermal therapy for deep-seated gliomas in children with neurofibromatosis type 1: report of two cases

PURPOSE

Nearly a quarter of neurofibromatosis type 1 (NF 1)- associated diencephalic low-grade tumors are refractory to chemotherapy. Addition of alternative treatment options with laser interstitial thermal therapy will have a positive impact on the outcome of these patients.

METHODS

We report on two illustrated cases of pediatric NF1- associated, chemoresistant, WHO grade 1 pilocytic astrocytomas treated with laser interstitial thermal therapy (LITT).

RESULTS

Both tumors responded favorably to LITT.

CONCLUSION

LITT should be considered as a treatment option for chemoresistant deep-seated NF1-associated low-grade gliomas.

Characterization of Dental Pulp Stem Cell Populations in the Teeth of Patients With Neurofibromatosis Type 1 - Therapeutic Potential for Bone Tissue Engineering

BACKGROUND/AIM

Neurofibromas (NF) are the most common benign nerve sheath tumors in the tongue, gingiva, major salivary glands, and jaw bones. Nowadays, tissue engineering is a revolutionary technique for reconstructing tissues. To explore the feasibility of using stem cells derived from NF teeth to treat orofacial bone defects, the differences in cell biological properties between an NF teeth group and Normal teeth group.

PATIENTS AND METHODS

The intra-dental pulp tissues from each tooth were extracted. The cell survival rates, morphology, proliferation rates, cell activity, and differentiation abilities were contrastively analyzed between the NF teeth group and Normal teeth group.

RESULTS

Between the two groups, there were no differences in the primary generation (P0) cells (p>0.05), the cell yield, and the time required for the cells to grow out of the pulp tissue and attach to the culture plate. Furthermore, no differences were found at the first generation (passage) between the two groups in colony formation rate and cell survival rate. The proliferation capacity, cell growth curve, and surface marker expression of dental pulp cells was not altered in the third generation (p>0.05).

CONCLUSION

Dental pulp stem cells from NF teeth were successfully obtained and were not different from normal dental pulp stem cells. Although, clinical research using tissue-engineered bone to repair bone defects is still in its infancy, it will eventually enter the clinic and become a routine means of bone defect reconstruction treatment as related disciplines and technologies develop.

[Translated article] Neurofibromatosis Type 1: Diagnostic Timelines in Children

BACKGROUND AND OBJECTIVES

Diagnosis of neurofibromatosis 1 (NF1) diagnosis is challenging in young children without a family history of NF1. The aims of this study were to estimate diagnostic delays in children without a family history of NF1 and to examine the effects of considering café-au-lait macules and skinfold freckling as a single diagnostic criterion.

PATIENTS AND METHODS

Retrospective, descriptive, observational study of all patients diagnosed with NF1 before the age of 18 years who were seen at our hospital. The medical records of those included were reviewed to identify the date on which the diagnostic criteria of NF1 were objectified. The patients were categorized into 2 groups: those with a known parental history of NF1 and those without. Café-au-lait macules and skinfold freckling were assessed as a single diagnostic criterion, and genetic evidence was considered to confirm highly suspicious cases.

RESULTS

We studied 108 patients younger than the age of 18 years with a diagnosis of NF1. Mean (SD) age at diagnosis was 3.94 (±3.8) years for the overall group, 1 year for patients with a parental history of NF1, and 4 years and 8 months for those without. Diagnosis was therefore delayed by 3 years and 8 months in patients without a family history.

CONCLUSION

Skin lesions were the first clinical manifestation of NF1 in most patients. We believe that the National Institutes of Health's diagnostic criteria for NF1 should be updated to aid diagnosis in young children.

The determinants of saccade targeting strategy in neurodevelopmental disorders: The influence of suboptimal reading experience

Whether eye-movements deficits are causal in reading disorders (RD) or rather a consequence of linguistic processing difficulty experienced by disabled readers has been extensively debated.Since RD are frequently comorbid with the Neurofibromatosis type1 (NF1), children with NF1 were used as a comparison group for children with dyslexia in this study.Eye movements were recorded while 21 dyslexic, 20 NF1, and 20 typically developing children performed an oculomotor lateralized bisection task. In this experiment, we manipulated the type of stimulus - discrete (words and strings of hashes) versus continuous (solid lines) - and the visual field where the stimulus was displayed (left vs right). The results showed that (1) only proficient readers (TD and NF1 without RD) showed fully developed oculomotor mechanisms for efficient reading, with a clear preferred viewing location located to the left of the word's centre in both visual fields, and fine-tuned saccade targeting guided by the between-character space information and (2) NF1 poor readers mirrored the dyslexic eye movement behaviour, with less accuracy and more variability in saccadic programming, no sensitivity to the discreteness of the stimuli, particularly in the left visual field. We concluded that disruption to oculomotor behaviour reflectsthe fact that many of the processes involved in reading are not yet automatized for children with RD, independently of NF1. This suggests that the differences in saccade targeting strategy between children with and without RD would be secondary consequences of their reduced reading experience.

Clinical Characteristics and Management of Children and Adults with Neurofibromatosis Type 1 and Plexiform Neurofibromas in Denmark: A Nationwide Study

INTRODUCTION

Plexiform neurofibromas (PN) are benign nerve sheath tumours that are a frequent and potentially debilitating complication in patients with neurofibromatosis type 1 (NF1). The objective of this study was to describe the natural history of PN in children, adolescents and adults with NF1.

METHODS

This was a nationwide, longitudinal cohort study of patients with NF1 under observation at the two national centres of NF1 expertise in Denmark between 2000 and 2020. Patient and clinical characteristics were documented from individual medical records.

RESULTS

A total of 1099 patients with NF1 were included. Overall, 12% (35/296) of paediatric patients and 21% (172/803) of adult patients had ≥ 1 large PN (≥ 3 cm). Approximately half of patients with a large PN had ≥ 1 symptomatic PN. The most frequent symptoms were pain, neurological deficits, cosmetic issues, disfigurement, compression, increased psychosocial burden and vision loss. Clinical evaluations of PN size were available for 40 PN in 34 paediatric patients and 191 PN in 159 adult patients with large PN. Surgery (complete resection or debulking) was performed in 38% (15/40) of PN in paediatric patients and 45% (86/191) in adult patients. In addition, 35% of PN in paediatric patients and 33% in adult patients were inoperable. In a subgroup analysis, the overall PN size increased 1.06-fold per year. Malignant peripheral nerve sheath tumours (MPNST) were diagnosed in 21 patients (two paediatric and 19 adult patients).

CONCLUSIONS

This study shows that PN are common, their size and prevalence increase with age, many are often inoperable and pain and other symptoms are frequently associated. The results highlight the severe sequelae and unmet need for alternatives to analgesia and surgery in patients with PN.

Precocious and accelerated puberty in children with neurofibromatosis type 1: results from a close follow-up of a cohort of 45 patients

PURPOSE

Central precocious puberty (CPP) in neurofibromatosis type 1 (NF1) occurs mainly in association with optic pathway glioma (OPG), but it can also develop in the absence of OPG. The aim of this study was to analyze the prevalence of puberty disorders in children with NF1 and its association with OPG and its location.

METHODS

A retrospective study of 45 children with NF1 (68.9% boys) followed at our center between 2008 and 2020 was conducted. A cerebral MRI scan was performed in all children. We analyzed auxological, laboratory, and imaging data of children with CPP or accelerated puberty (AP). Treatments used for CPP/AP and their effect on height were also evaluated.

RESULTS

The prevalence of puberty disorders in our cohort was 17.8% (male to female ratio of 7:1). CPP and AP were diagnosed in 8/45 (17.8%) NF1 children. Among children with puberty disorders, 5/8 (62.5%) had an OPG with chiasm involvement, 1/8 (12.5%) had an isolated optic nerve tumor, and 2/8 (25%) did not have any evidence of OPG on MRI. Fisher's exact test showed an association between CPP/AP and chiasm OPG (p = 0.025). Treatment with triptorrelin was initiated in 5/8 children, of whom four attained final predicted height.

CONCLUSION

Our study confirms the higher prevalence of CPP/AP in NF1 patients, as well as an association between chiasm OPG and puberty disorders. However, CPP/AP also occurred in the absence of OPG with an incidence of 9.1%. Comprehensive evaluation of every child with NF1 regardless of the presence of OPG is therefore essential.

Neurofibromatosis type 1 system-based manifestations and treatments: a review

INTRODUCTION

Neurofibromatosis type 1 (NF1) is a genetic disorder caused by a mutation in the NF1 gene. This disease presents with various system-based manifestations, including cardiac, musculoskeletal, and neuronal issues, which have been well-studied in previous research and have prompted the development of current and emerging treatments. These treatments, mainly medications targeting specific manifestations of NF1, aim to mitigate the negative impacts of the disease on patients' lives. NF1 is associated with an increased risk of malignancy and a significant decrease in life expectancy. In this paper, we review the current and emerging treatments for NF1 in relation to its system-based manifestations.

METHODS

We conducted an extensive literature search using specific keywords through databases such as PubMed, Scopus, and Cochrane. The articles we found were compiled and subjected to strict inclusion and exclusion criteria.

RESULTS

Pharmacological advances have led to the development of products that hold promise as future treatments for NF1. Given the diverse manifestations that can affect multiple organ systems in patients with NF1, it is important to consider a variety of treatment options to achieve optimal results. However, one of the major challenges in diagnosing and treating NF1 is that patients present asymptomatically, making it necessary to rely on clinical features for diagnosis.

CONCLUSION

In conclusion, NF1 is a complex disease with varying manifestations and a growing field of pharmacologic treatments. The information presented in this article synthesizes current knowledge and available therapies for NF1.

How to select the lowest instrumented vertebra in NF-1 non-dystrophic scoliosis

PURPOSE

To investigate lowest instrumented vertebra (LIV) selection strategy for neurofibromatosis type 1 (NF-1) non-dystrophic scoliosis.

METHODS

Consecutive eligible subjects with NF-1 non-dystrophic scoliosis were included. All patients were followed up at least for 24 months. Enrolled patients with LIV in stable vertebra were divided into stable vertebra group (SV group), and the other patients with LIV above the stable vertebra were divided into above stable vertebra group (ASV group). Demographic data, operative data, preoperative and postoperative radiographic data, and clinical outcome were collected and analyzed.

RESULTS

There were 14 patients in SV group (ten males and four females, mean age 13.9 ± 4.1 years) and 14 patients in ASV group (nine males and five females, mean age 12.9 ± 3.5 years). The mean follow-up period was 31.7 ± 17.4 months for patients in SV group and 33.6 ± 17.4 months for patients in ASV group, respectively. No significant differences were found in demographic data between two groups. The coronal Cobb angle, C7-CSVL, AVT, LIVDA, LIV tilt and SRS-22 questionnaire outcome significantly improved at the final follow-up in both groups. However, significantly higher loss of correction rate and increasement of LIVDA were found in ASV group. Two patients (14.3%) in ASV group but none in SV group suffered adding-on phenomenon.

CONCLUSIONS

Although patients in both SV and ASV groups obtained improved therapeutic efficacy at final follow-up, the radiographic and clinical outcome seemed more likely to deteriorate in ASV group after surgery. The stable vertebra should be recommended as LIV for NF-1 non-dystrophic scoliosis.

Neurofibromatosis-Noonan syndrome and growth deficiency in an Iranian girl due to a pathogenic variant in NF1 gene

BACKGROUND

Mutations in NF1 gene could cause allelic disorders with clinical spectrum of Neurofibromatosis type 1 to Noonan syndrome. Here, a 7-year-old Iranian girl is described with Neurofibromatosis-Noonan syndrome due to a pathogenic variant in NF1 gene.

METHODS

Clinical evaluations were performed along with genetic testing using whole exome sequencing (WES). The variant analysis including pathogenicity prediction was also done using bioinformatics tools.

RESULTS

The chief compliant of the patient was short stature and lack of proper weight gain. Other symptoms were developmental delay, learning disability, inadequate speech skill, broad forehead, hypertelorism, and epicanthal folds, low set ears and webbed neck. A small deletion, c.4375-4377delGAA, was found in NF1 gene using WES. This variant was classified as pathogenic according to ACMG.

CONCLUSIONS

NF1 variants may show variable phenotypes among the patients; identifying such variants is helpful in therapeutic management of the disease. WES is considered as an appropriate test to diagnose Neurofibromatosis-Noonan syndrome.

Updates in the Management of Central and Peripheral Nervous System Tumors among Patients with Neurofibromatosis Type 1 and Neurofibromatosis Type 2

BACKGROUND

Neurofibromatosis type 1 and neurofibromatosis type 2 are unrelated, distinct genetic disorders characterized by the development of central and peripheral nervous system tumors.

SUMMARY

Neurofibromatosis type 1 is the most common inherited tumor predisposition syndrome with a lifelong increased risk of benign and malignant tumor development, such as glioma and nerve sheath tumors. Neurofibromatosis type 2 classically presents with bilateral vestibular schwannoma, yet it is also associated with non-vestibular schwannoma, meningioma, and ependymoma. Historically, the number of effective therapies for neurofibromatosis-related neoplasms has been limited.

KEY MESSAGE

In the past decade, there have been significant advances in the development of precision-based therapies for NF-associated tumors with an increased emphasis on functional outcomes in addition to tumor response. Continued scientific discovery and advancement of targeted therapies for NF-associated neoplasms are necessary to continue to improve outcomes for patients with NF.

ERN GENTURIS tumour surveillance guidelines for individuals with neurofibromatosis type 1

BACKGROUND

Neurofibromatosis type 1 (NF1) is a multisystem genetic disorder, predisposing development of benign and malignant tumours. Given the oncogenic potential, long-term surveillance is important in patients with NF1. Proposals for NF1 care and its specific manifestations have been developed, but lack integration within routine care. This guideline aims to assimilate available information on NF1 associated tumours (based on evidence and/or expert opinion) to assist healthcare professionals in undertaking tumour surveillance of NF1 individuals.

METHODS

By comprehensive literature review, performed March 18th 2020, guidelines were developed by a NF1 expert group and patient representatives, conversant with clinical care of the wide NF1 disease spectrum. We used a modified Delphi procedure to overcome issues of variability in recommendations for specific (national) health care settings, and to deal with recommendations based on indirect (scarce) evidence.

FINDINGS

We defined proposals for personalised and targeted tumour management in NF1, ensuring appropriate care for those in need, whilst reducing unnecessary intervention. We also incorporated the tumour-related psychosocial and quality of life impact of NF1.

INTERPRETATION

The guideline reflects the current care for NF1 in Europe. They are not meant to be prescriptive and may be adjusted to local available resources at the treating centre, both within and outside EU countries.

FUNDING

This guideline has been supported by the European Reference Network on Genetic Tumour Risk Syndromes (ERN GENTURIS). ERN GENTURIS is funded by the European Union. DGE is supported by the Manchester NIHRBiomedical Research Centre (IS-BRC-1215-20007).

The role of visual electrodiagnostics in management of children with neurofibromatosis type 1

PURPOSE

To evaluate the role of visual electrodiagnostic testing in children with neurofibromatosis type 1 (NF1) despite improved accessibility to magnetic resonance imaging (MRI).

METHODS

The records from 39 children (78 eyes, 15 boys, 24 girls, average age at last visit of 11.5 ± 4.3 years, average follow-up time of 7.8 ± 3.9 years) with genetically confirmed NF1 were retrospectively analysed. They all underwent a thorough ophthalmological investigation, including age-appropriate visual acuity testing, anterior segment evaluation for Lisch nodules and a dilated fundus examination. If children were cooperative enough, colour vision was tested using the Hardy-Rand-Rittler test, visual fields were evaluated with Goldmann perimetry. All performed MRI of the brain and orbits as part of the standard of care protocol. Visual electrodiagnostics included electroretinography (ERG) and visual evoked potentials (VEP) using a standard protocol in older children, whereas with less cooperative children a modified protocol according to the Great Ormond Street Hospital (GOSH protocol) was used.

RESULTS

The average visual acuity was 0.8 ± 0.3, colour vision was abnormal in 6%, perimetry in 8%, Lisch nodules were present in 62%, and the optic disc was pale in 66% of all eyes. Plexiform neurofibroma of the eyelid/orbit was present in 4%. Optic pathway glioma (OPG) was detected with MRI in 22 (57%) and in 6/22 treatment was indicated. Other intracranial NF1-related lesions were documented in 70% of children. VEP were abnormal in 16/39 of all children with NF1 (41%) comprising 14/22 (65%) of children with confirmed OPG and 2/17 (12%) of children without OPG. All full-field and pattern ERG responses were within normal limits. All individual VEP results are described and three cases from this cohort of children are presented in detail to illustrate the importance of VEP testing. In Case 1, VEP abnormality suggested subsequent MRI of the brain under general anaesthesia, which was otherwise contraindicated according to normal clinical findings and his young age. In Cases 2 and 3, VEP provided more precise functional information during the follow-up of OPG, while other psychophysical tests remained unchanged.

CONCLUSIONS

Electrodiagnostics has multifactorial role and importance in children with NF1, either when visual pathway function is impaired in young children, even before MRI under general anaesthesia and other psychophysical tests can be performed, as well as for a more precise monitoring of the visual pathway function before potential treatment of OPG, or after it, to evaluate its success.

Inhibition of YAP Sensitizes the Selumetinib Treatment for Neurofibromatosis Type 1 Related Plexiform Neurofibroma

Background: Targeted therapy of Neurofibromatosis type 1 (NF1) related plexiform neurofibroma (pNF) aiming at MEK molecule has not demonstrated a convincing result for complete disease inhibition, probably due to other signal pathways crosstalk. Our previous study revealed an increased nuclear translocation of YAP molecule in NF1 related pNF. Herein, we decided to further investigate the therapeutic relations of YAP interference during the MEK treatment against NF1 related pNF. Methods: By means of selumetinib (MEK-inhibitor), RNA-sequencing was firstly performed to identify the changes of signal pathways in pNF Schwann cells, which was probably related to YAP regulation. Nuclear-cytoplasmic fractionation and western blotting were performed to show the intracellular YAP changes under selumetinib treatment. Thirdly, a series of in vitro assays were performed including flow cytometry, CCK-8, and colony/sphere formation under dual treatment of selumetinib and verteporfin (YAP-inhibitor). In addition, Chou-Talalay method was adopted to evaluate the synergistic inhibiting effects of such drug combination. Xenograft study was also used to detect the combining effects in vivo. Results: RNA-sequencing revealed that selumetinib treatment might be associated with the undesirable activation of Hippo pathway in NF1 related pNF tumor cells, which might reduce its pharmaceutic effects. Next, nuclear-cytoplasmic fractionation and further studies demonstrated that selumetinib could promote the nuclear translocation and transcriptional activation of YAP in vitro, which might cause the aforementioned resistance to selumetinib treatment. Additionally, when combined treatments were performed based on verteporfin and selumetinib, synergistic effects were observed on cytotoxicity of NF1 related pNF tumor cells in vitro and in vivo xenograft models. Conclusion: YAP inhibition can effectively sensitize NF1 related pNF tumor cells to selumetinib. Dual targeting of YAP and MEK might be a promising therapeutic strategy for treating NF1 related pNF.

Expanded analysis of high-grade astrocytoma with piloid features identifies an epigenetically and clinically distinct subtype associated with neurofibromatosis type 1

High-grade astrocytoma with piloid features (HGAP) is a recently recognized glioma type whose classification is dependent on its global epigenetic signature. HGAP is characterized by alterations in the mitogen-activated protein kinase (MAPK) pathway, often co-occurring with CDKN2A/B homozygous deletion and/or ATRX mutation. Experience with HGAP is limited and to better understand this tumor type, we evaluated an expanded cohort of patients (n = 144) with these tumors, as defined by DNA methylation array testing, with a subset additionally evaluated by next-generation sequencing (NGS). Among evaluable cases, we confirmed the high prevalence CDKN2A/B homozygous deletion, and/or ATRX mutations/loss in this tumor type, along with a subset showing NF1 alterations. Five of 93 (5.4%) cases sequenced harbored TP53 mutations and RNA fusion analysis identified a single tumor containing an NTRK2 gene fusion, neither of which have been previously reported in HGAP. Clustering analysis revealed the presence of three distinct HGAP subtypes (or groups = g) based on whole-genome DNA methylation patterns, which we provisionally designated as gNF1 (n = 18), g1 (n = 72), and g2 (n = 54) (median ages 43.5 years, 47 years, and 32 years, respectively). Subtype gNF1 is notable for enrichment with patients with Neurofibromatosis Type 1 (33.3%, p = 0.0008), confinement to the posterior fossa, hypermethylation in the NF1 enhancer region, a trend towards decreased progression-free survival (p = 0.0579), RNA processing pathway dysregulation, and elevated non-neoplastic glia and neuron cell content (p < 0.0001 and p < 0.0001, respectively). Overall, our expanded cohort broadens the genetic, epigenetic, and clinical phenotype of HGAP and provides evidence for distinct epigenetic subtypes in this tumor type.

Quality of life in patients with neurofibromatosis type 1: a nationwide database study in Japan from 2015 to 2019

BACKGROUND

This study examined the association between dermatological, neurological, and bone manifestations of neurofibromatosis type 1 (NF1) and quality of life (QoL) in patients with NF1 using a nationwide database of all patients who newly claimed for medical expense subsidies in Japan from 2015 to 2019.

METHODS

The Japanese Ministry of Health, Labour and Welfare provided the "National Database of Designated Intractable Diseases of Japan" containing clinical and personal records ("Medical Certificates of Designated Intractable Diseases") of all patients with NF1 following approval of the study protocol. To examine the association between the severity of symptoms and QoL, multinominal logistic regression analyses were performed, adjusted for potential confounders.

RESULTS

The final study population consisted of 1,487 patients (775 females and 712 males; mean (standard deviation) age, 45.4 (17.9) years). More than 50% and nearly 45% of participants were recorded as having moderate or severe "pain/discomfort" and "anxiety/depression," respectively. The severity of neurological symptoms was significantly associated with all components of QoL, whereas the severity of dermatological symptoms was significantly associated with only moderate or severe subjective and mental health-related components of QoL, and the severity of bone lesions was associated with only moderate or severe physical health-related components of QoL. Subjective and mental health-related components of QoL tended to be deteriorated more than physical health-related components of QoL in younger and female patients.

CONCLUSIONS

Severities of neurological and dermatological symptoms were significantly associated with subjective and mental health-related components of QoL, while the severity of bone symptoms was associated with only moderate and severe deterioration of physical health-related components of QoL.

MicroRNA-217 aggravates breast cancer through activation of NF1-mediated HSF1/ATG7 axis and c-Jun/ATF3/MMP13 axis

Application of microRNA-mediated mRNA expression in treatment of diverse cancers has been documented. The current study was explored to study the role of miR-217 in breast cancer (BC) progression and the related downstream factors. Clinical tissue samples, BC cell lines and the established xenograft models were prepared for ectopic expression and depletion experiments to discern the regulatory roles of miR-217-mediated NF1 in BC cell proliferation, metastasis and chemoresistance as well as tumorigenic ability of BC cells in nude mice. miR-217 was upregulated in BC, which was a predictor of poor prognosis of BC patients. NF1 could be targeted by miR-217. miR-217 promoted malignant characteristics of BC cells through enhancing ATF3-MMP13 interaction by inhibiting NF1. miR-217 repressed sensitivity against anti-cancer drugs by inducing autophagy of BC cells through the NF1/HSF1/ATG7 axis. Also, miR-217 could inhibit NF1 to facilitate tumorigenic ability of BC cells in vivo. Our study emphasized that miR-217 could potentially inhibit NF1 expression to activate the c-Jun, thus enhancing the expression and interaction of ATF3/MMP13 and promoting the malignant features of BC cells. Furthermore, miR-217 conferred chemoresistance on BC by enhancing BC cell autophagy, which was achieved by limiting NF1 expression to induce the HSF1/ATG7 pathway.

Treatment of Cutaneous Neurofibromas in Patients with Neurofibromatosis Type 1

Neurofibromatosis type 1 is a genetic disorder impacting approximately 2.5 million people worldwide, often leading to development of numerous benign yet disfiguring cutaneous neurofibromas (cNF). Removal of cNF is limited to excision or laser ablation with common post-operation complications and scarring. The current case explores a new approach to removal or reduction of cNF by a minimally invasive and pain-reduced treatment modality. A 40-year-old female patient with numerous cNF across her body underwent a single treatment using a 20 MHz dermatologically focused ultrasound device on seven selected cNF on the upper back. Each cNF was treated in a single session of 20-60 s without anesthesia due to manageable pain. Only one minimal adverse reaction in the form of dyspigmentation in a single treated tumor was noted from treatment or during the healing of a thin scab that formed on each cNF a few days after treatment. At the 12-month follow-up, four out of seven treated cNF showed full remission, two showed partial or significant reduction in tumor volume, while two did not respond to treatment. The reason for the variability is not fully understood, but speculations include difference in tissue content, e.g., due to tumor age. The method is concluded to be a promising candidate for a new safe and minimally invasive treatment that can potentially be used for single-session removal/reduction of a large number of cNF. Further research should focus on refining treatment parameters and strategies to enhance response predictability.

A Novel Hybrid Technique in the Treatment of Dystrophic Scoliosis Secondary to Neurofibromatosis Type 1 Lacking Pedicles in the Apical Area

STUDY DESIGN

A retrospective observational study.

OBJECTIVE

To introduce a novel hybrid technique using segmentation correction (SC) and to compare it with traditional correction (TC) in treating dystrophic scoliosis secondary to neurofibromatosis type 1 (NF1-S) lacking pedicles in the apical area.

METHODS

We reviewed the NF1-S cases lacking pedicles diagnosed in our hospital between January 2015 and December 2019. Patients were divided into the SC and TC groups and were followed up for at least 2 years. The degree of deformities, correction rate, and vertebral rotatory subluxation (RS) were assessed before the operation, post-traction, post operation, and during follow-up visits.

RESULTS

A total of 27 patients were included in the SC group and 21 in the TC group. There was no significant difference in the 2 groups before the surgery regarding age, height, weight, degree of deformities, and spinal flexibility. The correction rate of patients in the SC group was higher (57.7% ± 17.3% vs. 40.9% ± 19.0%, P = 0.002) than in the TC group. During the 2-year follow-up, the loss of Cobb angles of the SC group in both coronal and sagittal planes were lower than those of the TC group (coronal plane, 1.2° ± 1.1° vs. 2.0° ± 1.4°, P = 0.039; sagittal plane, 0.9° ± 0.5° vs. 1.7° ± 1.0°, P = 0.002).

CONCLUSIONS

The SC technique showed better deformity correction than TC, suggesting that SC may be an alternative method for treating NF1-S patients lacking pedicles in the apical area.

A Review of Spinal Lesions in Neurofibromatosis Type 1 in a Large Neurofibromatosis Type 1 Center

BACKGROUND

Spinal lesions are a known manifestation of neurofibromatosis type 1 (NF1). The aim of this retrospective review was to analyze and report the prevalence of spinal lesions on imaging in a large NF1 center.

METHODS

The data were collected from a period of 62 months from a cohort of 514 patients. Data were collected from multidisciplinary team meeting reports that included radiologic reports of each patient investigating 20 distinct variables. The prevalence of each of these lesions was calculated, and any statistically significant associations were investigated using the χ² test.

RESULTS

Four-hundred forty-seven patients had classic NF1, and 67 patients had spinal NF1. Many of the patients had spinal abnormalities; 25.7% of these patients were found to have dural ectasia, whereas 44.9% of patients had a spinal deformity. A statistically significant association between dural ectasia and spinal neurofibromatosis was established (P < 0.05). An additional statically significant association was established between dural ectasia and spinal deformity (P < 0.00001). The patients with spinal nerve root tumors were identified, and it was found that 49.8% of patients possessed these tumors, whereas 56.3% of these tumors were intraspinal tumors. The most common region affected was the cervical spine, and the most common spinal level was C2.

CONCLUSIONS

This high prevalence of spinal tumours in mobile areas of the spine is possibly the result of a combination of genetic predisposition and repeated microtraumas resulting in tumor formation. This is the largest reported study of spinal lesions in NF1 based on imaging and offers insights into the etiology and relationships between lesions.

Neurofibromatosis type 1 in Syrian older patient presented with gastric outlet obstruction

Neurofibromatosis type 1 is an autosomal dominant disorder with cutaneous features and multiple tumors that involve different organs. Gastrointestinal stromal tumors are non-epithelial tumors associated with neurofibromatosis type 1 and arise from the gastrointestinal tract. Patients with gastrointestinal stromal tumor present most commonly with anemia due to overt or occult bleeding and in rare cases diagnosis might be delayed so patients present with gastrointestinal tract obstruction. Here, we report a rare case of an older patient with neurofibromatosis type 1, who was undiagnosed and presented with acute abdomen due to gastric outlet obstruction. It was caused by progressive gastrointestinal stromal tumor in the antrum of the stomach. Gastrointestinal stromal tumors should be considered in the differential diagnosis of gastric outlet obstruction, especially in patients with neurofibromatosis type 1.

Role of nerves in neurofibromatosis type 1-related nervous system tumors

BACKGROUND

Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder that affects nearly 1 in 3000 infants. Neurofibromin inactivation and NF1 gene mutations are involved in various aspects of neuronal function regulation, including neuronal development induction, electrophysiological activity elevation, growth factor expression, and neurotransmitter release. NF1 patients often exhibit a predisposition to tumor development, especially in the nervous system, resulting in the frequent occurrence of peripheral nerve sheath tumors and gliomas. Recent evidence suggests that nerves play a role in the development of multiple tumor types, prompting researchers to investigate the nerve as a vital component in and regulator of the initiation and progression of NF1-related nervous system tumors.

CONCLUSION

In this review, we summarize existing evidence about the specific effects of NF1 mutation on neurons and emerging research on the role of nerves in neurological tumor development, promising a new set of selective and targeted therapies for NF1-related tumors.

A fortuitous discovery of a neurofibroma in a female patient with type 1 neurofibromatosis: a case report

Neurofibromatosis type 1 (NF1) is a neurocutaneous condition with an autosomal dominant pattern of inheritance. This congenital disease is characterized by a wide spectrum of clinical manifestations and degree of severity. This case report describes a female patient in her early 20s who presented with a complaint of lumbosciatica-like pain evolving for several months. The condition initially escaped the attention of clinicians until a lumbar computed tomography scan and spinal magnetic resonance imaging were performed. The patient was then transferred to the general surgery department, where a clinical diagnosis of NF1 was established. The clinical manifestations were specific for this disease, including café-au-lait macules, plexiform neurofibroma, and a history of neurofibromatosis in her mother. The patient underwent surgical resection of the neurofibroma, which resulted in a favorable outcome. However, 2 years later, a new mass attached to the second lumbar spinal nerve was revealed by a follow-up computed tomography scan. Long-term and close follow-up of NF1 is required because of the high risk of malignancy and recurrence in NF1 patients.