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Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder characterized by the predisposition to develop tumors such as malignant peripheral nerve sheath tumors (MPNSTs) which represents the primary cause of death for NF1-affected patients. Regardless of the high incidence and mortality, the molecular mechanisms underneath MPNST growth and metastatic progression remain poorly understood. In this proof-of-concept study, we performed somatic whole-exome sequencing (WES) to profile the genomic alterations in four samples from a patient with NF1-associated MPNST, consisting of a benign plexiform neurofibroma, a primary MPNST, and metastases from lung and skin tissues. By comparing genomic patterns, we identified a high level of variability across samples with distinctive genetic changes which allow for the definition of profiles of the early phase with respect to the late metastatic stages. Pathogenic and likely pathogenic variants were abundant in the primary tumor, whereas the metastatic samples exhibited a high level of copy-number variations (CNVs), highlighting a possible genomic instability in the late phases. The most known MPNST-related genes, such as TP53 and SUZ12, were identified in CNVs observed within the primary tumor. Pathway analysis of altered early genes in MPNST pointed to a potential role in cell motility, division and metabolism. Moreover, we employed survival analysis with the TCGA sarcoma genomic dataset on 262 affected patients, in order to corroborate the predictive significance of the identified early and metastatic MPNST driver genes. Specifically, the expression changes related to the mutated genes, such as in RBMX, PNPLA6 and AGAP2, were associated with reduced patient survival, distinguishing them as potential prognostic biomarkers. This study underlines the relevance of integrating genomic results with clinical information for early diagnosis and prognostic understanding of tumor aggressiveness. [ABSTRACT FROM AUTHOR]

Simple Summary: The landscape of malignant peripheral nerve sheath tumours (MPNSTs) is usually challenging both in terms of recognition and management. Despite a low incidence in the general population (0.001%), MPNST is an important cause of mortality in the neurofibromatosis type 1 (NF1) population. It is essential for a multi-disciplinary collaboration to achieve the best possible outcome. The aim of our paper was to contribute with a comprehensive review from the literature of the best multi-modality ways that show improvements in terms of survival and address potential future treatment approaches based on the molecular alterations seen in these tumours. Malignant peripheral nerve sheath tumours (MPNST) are aggressive sarcomas that have nerve sheath differentiation and can present at any anatomical site. They can arise from precursor neurofibroma in the context of neurofibromatosis type 1 (NF1) or as de novo and sporadic tumours in the absence of an underlying genetic predisposition. The primary therapeutic approach is most often radical surgery, with non-surgical modalities playing an important role, especially in locally advanced or metastatic cases. The aim of multimodality approaches is to optimize both local and systemic control while keeping to a minimum acute and late treatment morbidity. Advances in the understanding of the underlying biology of MPNSTs in both sporadic and NF-1-related contexts are essential for the management and implementation of novel therapeutic approaches. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder resulting from mutations in the NF1 gene. Patients harboring these mutations are predisposed to a spectrum of peripheral nerve sheath tumors (PNSTs) originating from Schwann cells, of which malignant peripheral nerve sheath tumors (MPNSTs) are the deadliest, with limited treatment options. Therefore, an unmet need still exists for more effective therapies directed at these aggressive malignancies. Cold atmospheric plasma (CAP) is a reactive oxygen species (ROS) and reactive nitrogen species (RNS) generating ionized gas that has been proposed to be a potential therapeutic modality for cancer. In this study, we sought to determine the effects of CAP on NF1-associated PNSTs. Utilizing established mouse and human cell lines to interrogate the effects of CAP in both in vitro and in vivo settings, we found that NF1-associated PNSTs were highly sensitive to CAP exposure, resulting in cell death. To our knowledge, this is the first application of CAP to NF1-associated PNSTs and provides a unique opportunity to study the complex biology of NF1-associated tumors. [ABSTRACT FROM AUTHOR]

Background: Neurofibromatosis type 1 (NF1) is a genetic disorder that affects multiple systems in the body, often leading to physical disfigurements and a wide range of clinical symptoms. This study aims to investigate the relationship between NF1 severity and visibility and the quality of life (QoL) in children. Methods: The Pediatric Quality of Life Inventory (PedsQL) and a modified version of the Ablon scale were used to assess QoL and NF1 severity and visibility, respectively. Self-reported and parent-reported QoL scores were compared, and the associations between NF1 severity/visibility and QoL were explored. Results: Thirty-eight pediatric NF1 patients and their parents were enrolled. QoL scores did not differ significantly between patient self-reports and parent reports. However, correlational analyses revealed that higher NF1 severity was associated with lower physical QoL in patients, and greater NF1 visibility was linked to lower physical and social QoL. For parents, higher NF1 severity correlated with lower school functioning, whereas NF1 visibility did not show a significant correlation with QoL. Conclusion: The severity and visibility of NF1 have distinct impacts on various aspects of QoL in children, highlighting the need for tailored interventions that address both physical and psychological challenges. These findings underscore the importance of comprehensive care approaches in managing NF1 in pediatric populations. [ABSTRACT FROM AUTHOR]

Simple Summary: Plexiform neurofibromas in neurofibromatosis type 1 (pNF1), characterized by aggressive growth and local invasiveness, are comprised primarily of Schwann cell-derived tumor cells (Nf1−/−) and the tumor microenvironment (TME). Fibroblasts (Nf1+/−), the most abundant cell type in the TME, are known to significantly contribute to pNF1 formation, but their precise role in the subsequent tumor progression is poorly understood. Using our established three-dimensional (3D) culture models with patient-derived pNF1 cells and fibroblasts, we observed that the fibroblast-derived secretome stimulates the growth and local invasiveness of pNF1 spheroids. Depletion of small extracellular vesicles (sEVs) from the fibroblast secretome completely eliminated the paracrine effect on pNF1 spheroid growth. These results suggest that targeting paracrine interactions between pNF1 tumor cells and fibroblasts may offer a potential therapeutic approach for reducing pNF1 tumor progression. Plexiform neurofibromas (PNs) occur in about a half of neurofibromatosis type 1 (NF1) patients and have garnered significant research attention due to their capacity for growth and potential for malignant transformation. NF1 plexiform neurofibroma (pNF1) is a complex tumor composed of Schwann cell-derived tumor cells (Nf1−/−) and the tumor microenvironment (TME). Although it has been widely demonstrated that the TME is involved in the formation of neurofibromas, little is known about the effects of the TME on the subsequent progression of human pNF1. Elucidating the molecular interactions between tumor cells and the TME may provide new therapeutic targets to reduce the progression of pNF1. In the present study, we focused on the contributions of fibroblasts, the most abundant cell types in the TME, to the growth of pNF1. To simulate the TME, we used a three-dimensional (3D) coculture model of immortalized pNF1 tumor cells (Nf1−/−) and primary fibroblasts (Nf1+/−) derived from pNF1 patients. We performed live-cell imaging of 3D/4D (3D in real-time) cultures through confocal microscopy followed by 3D quantitative analyses using advanced imaging software. The growth of pNF1 spheroids in 3D cocultures with fibroblasts was significantly greater than that of pNF1 spheroids in 3D monocultures. An increase in the growth of pNF1 spheroids also occurred when they were cultured with conditioned media (CM) from fibroblasts. Moreover, fibroblast-derived CM increased the invasive outgrowth and further local invasion of pNF1 spheroids. Interestingly, when small extracellular vesicles (sEVs) were depleted from the fibroblast-derived CM, the stimulation of the growth of pNF1 spheroids was lost. Our results suggest that fibroblast-derived sEVs are a therapeutic target for reducing the growth of pNF1. [ABSTRACT FROM AUTHOR]

Simple Summary: Although a large number of NF1 variants have been cataloged in public databases, known NF1 genotype-phenotype correlations are still limited. Through a retrospective analysis of a large cohort of NF1 patients at the Medical Genomics Laboratory of the University of Alabama at Birmingham, we established a novel NF1 genotype-phenotype correlation. Specifically, NF1 patients with NF1 exon 24 [19a] skipping typically exhibit a mild phenotype, characterized by the absence of severe NF1-specific clinical features, including neurofibromas. This newly established genotype-phenotype correlation will help clinicians improve the management of patients harboring NF1 exon 24 [19a] skipping variants and provide a new therapeutic target for NF1 treatment. Neurofibromatosis type 1 (NF1) is an autosomal dominant neurocutaneous disorder caused by loss-of-function variants in the NF1 gene. As of 20 November 2023, over 5000 distinct pathogenic or likely pathogenic variants have been reported in public databases. However, only a few NF1 genotype–phenotype correlations have been established so far. In this study, we present findings on 40 individuals with NF1, comprising 26 unrelated probands and 14 affected relatives, who carry one of nine NF1 heterozygous pathogenic splicing variants, all of which result in the in-frame skipping of exon 24 [19a] (NM_000267.3:r.3114_3197del, p.Asn1039_Arg1066del). These variants include c.3114-2A>G, c.3114-1G>A, c.3196A>G, c.3197G>A, c.3197G>T, c.3197+1G>A, c.3197+1G>T, c.3197+2T>C, and c.3197+3A>T. Among individuals with these variants, none exhibit externally visible plexiform neurofibromas, histopathologically confirmed cutaneous or subcutaneous neurofibromas, symptomatic spinal neurofibromas, or symptomatic optic pathway gliomas. The most prevalent, and sometimes sole, clinical feature observed in this cohort is multiple café-au-lait macules, with or without skinfold freckles: 85% and 60.5% of the individuals display six or more café-au-lait macules and freckles, respectively. In comparison to established NF1 genotype–phenotype correlations, these patients demonstrate highly similar clinical presentations to those associated with the NF1 pathogenic variant c.2970_2972del (p.Met992del), known for resulting in the mildest clinical features. Despite the generally mild phenotype, cognitive impairment, developmental delay, and/or learning difficulties are still observed in 33.3% of these patients, suggesting that learning challenges remain a prominent aspect of the phenotypic presentation in these individuals and necessitate specialized care. This newly established genotype–phenotype correlation will assist clinicians in improving the management of patients harboring NF1 exon 24 [19a] skipping variants and provide a new therapeutic target for NF1 treatment. [ABSTRACT FROM AUTHOR]

Malignant Peripheral Nerve Sheath Tumors (MPNSTs) are aggressive sarcomas that can arise both sporadically and in patients with the genetic syndrome Neurofibromatosis type 1 (NF1). Prognosis is dismal, as large dimensions, risk of relapse, and anatomical localization make surgery poorly effective, and no therapy is known. Hence, the identification of MPNST molecular features that could be hit in an efficient and selective way is mandatory to envision treatment options. Here, we find that MPNSTs express high levels of the glycolytic enzyme Hexokinase 2 (HK2), which is known to shield cancer cells from noxious stimuli when it localizes at MAMs (mitochondria-associated membranes), contact sites between mitochondria and endoplasmic reticulum. A HK2-targeting peptide that dislodges HK2 from MAMs rapidly induces a massive death of MPNST cells. After identifying different matrix metalloproteases (MMPs) expressed in the MPNST microenvironment, we have designed HK2-targeting peptide variants that harbor cleavage sites for these MMPs, making such peptides activatable in the proximity of cancer cells. We find that the peptide carrying the MMP2/9 cleavage site is the most effective, both in inhibiting the in vitro tumorigenicity of MPNST cells and in hampering their growth in mice. Our data indicate that detaching HK2 from MAMs could pave the way for a novel anti-MPNST therapeutic strategy, which could be flexibly adapted to the protease expression features of the tumor microenvironment. [ABSTRACT FROM AUTHOR]

Background: type 1 neurofibromatosis (NF1) is the most common neurocutaneous disorder, and it is an inherited condition that causes a tumour predisposition. Central nervous system (CNS) manifestations are a significant cause of morbidity and mortality in NF1. We provide a pictorial review of neuroradiological features of NF1, with emphasis on magnetic resonance imaging (MRI), and we assess the frequency of those features on a cohort of NF1 patients. Methods: we retrospectively evaluated all patients with a diagnosis of NF1 who underwent MRI of the spine and brain in our centre over a period of almost 5 years. A total of 74 patients were enrolled, 28 males and 46 females, with a mean age of 21 ± 12.67 years. The frequency of CNS manifestations encountered in our cohort of NF1 patients was assessed and compared with the data found in other studies published in the literature. Results: many of our findings were in line with the literature, and possible interpretations for those that turned out to be different were suggested in the discussion. Conclusion: imaging plays a central role in the diagnosis and management of NF1, and the knowledge of CNS manifestations could be critical for its early detection and identification, such as for treatment planning and prognostic implications. [ABSTRACT FROM AUTHOR]

Objectives: Simultaneous removal and cochlear implantation (CI) have been reported in intralabyrinthine and intracochlear schwannoma. A wide range of postoperative hearing outcomes have been reported after CI in these cases. This study evaluated the outcomes of performing a simultaneous resection of Schwannoma in cochlea and cochlear implantation (CI), aiming to assess the effectiveness of this combined surgical approach for hearing rehabilitation with CI. Methods: This retrospective case series was conducted at a tertiary care center. The study included four consecutive patients with profound sensorineural hearing loss due to a mass inside the cochlea. These patients underwent simultaneous single-sided CI and tumor resection performed by the same surgeon. Preoperative and postoperative audiological assessments were conducted to evaluate the patients' hearing outcomes before and after the surgical intervention. Results: Simultaneous CI with tumor resection was successful in all cases. Two of the four patients had a unilateral tumor, while the other two had a bilateral tumor with the involvement of the internal auditory canal and cerebellopontine angle (neurofibromatosis type 2 (NF2)). In two cases of unilateral tumor, aided free-field pure tone average (PTA) was 26 dB, and 46 dB hearing level (HL), and word recognition score (WRS) at 65 dB was 40% and 68%, respectively, 3 months after surgery. In two cases of tumor with NF2, aided free-field PTA was 36 dB and 60 dB HL, and both cases showed 0% WRS at 65 dB 3 months after surgery. Conclusions: Simultaneous schwannoma excision and CI in patients with Schwannoma inside cochlea are surgically practical and safe. Postoperatively, there was a notable improvement in hearing in cases of sporadic schwannoma, regardless of the type of CI used. However, there was 0% WRS in the two NF2 patients with a mass in the internal auditory canal. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is a neurocutaneous disorder. Plexiform neurofibromas (PNFs) are benign tumors commonly formed in patients with NF1. PNFs have a high incidence of developing into malignant peripheral nerve sheath tumors (MPNSTs) with a 5-year survival rate of only 30%. Therefore, the accurate diagnosis and differentiation of MPNSTs from benign PNFs are critical to patient management. We studied a fluorine-18 labeled tryptophan positron emission tomography (PET) radiotracer, 1-(2-[18F]fluoroethyl)-L-tryptophan (L-[18F]FETrp), to detect NF1-associated tumors in an animal model. An ex vivo biodistribution study of L-[18F]FETrp showed a similar tracer distribution and kinetics between the wild-type and triple mutant mice with the highest uptake in the pancreas. Bone uptake was stable. Brain uptake was low during the 90-min uptake period. Static PET imaging at 60 min post-injection showed L-[18F]FETrp had a comparable tumor uptake with [1⁸F]fluorodeoxyglucose (FDG). However, L-[18F]FETrp showed a significantly higher tumor-to-brain ratio than FDG (n = 4, p < 0.05). Sixty-minute-long dynamic PET scans using the two radiotracers showed similar kidney, liver, and lung kinetics. A dysregulated tryptophan metabolism in NF1 mice was further confirmed using immunohistostaining. L-[18F]FETrp is warranted to further investigate differentiating malignant NF1 tumors from benign PNFs. The study may reveal the tryptophan–kynurenine pathway as a therapeutic target for treating NF1. [ABSTRACT FROM AUTHOR]

Simple Summary: Pancreatic neuroendocrine tumors (PanNETs) and lung NETs (LNETs) have garnered increased attention in recent years due to their diverse clinical manifestations and challenging management. Although the vast majority of both PanNETs and LNETs are sporadic, they can also occur in the context of inherited syndromes that necessitate a high index of suspicion as the course of the disease is different and there are additional clinical implications for other family members. Our systematic review encompasses studies conducted over the past decade, focusing on the incidence, diagnosis, and treatment of PanNETs and/or LNETs encountered in hereditary syndromes such as Multiple Endocrine Neoplasia type 1 (MEN1), MEN4, von Hippel–Lindau (VHL), Tuberous Sclerosis Complex (TSC), and Neurofibromatosis type 1 (NF1). We discuss the importance of early detection and tailored management strategies, emphasizing the need for multidisciplinary collaboration among relevant healthcare professionals to optimize patients' outcomes. Moreover, we highlight the importance of active surveillance strategies for early tumor detection in high-risk individuals and the evolving landscape of personalized medicine for targeted intervention. Pancreatic neuroendocrine tumors (PanNETs) and lung NETs (LNETs) represent a rare but clinically significant subgroup of neoplasms. While the majority is sporadic, approximately 17% of PanNETs and a subset of LNETs develop in the context of monogenic familial tumor syndromes, especially multiple endocrine neoplasia type 1 (MEN1) syndrome. Other inherited syndromes associated with PanNETs include MEN4, von Hippel–Lindau (VHL) syndrome, neurofibromatosis type 1 (NF1), and tuberous sclerosis complex (TSC). These syndromes are highly penetrant and their clinical manifestations may vary even among members of the same family. They are attributed to genetic mutations involving key molecular pathways regulating cell growth, differentiation, and angiogenesis. Pancreatic NETs in hereditary syndromes are often multiple, develop at a younger age compared to sporadic tumors, and are associated with endocrine and nonendocrine tumors derived from multiple organs. Lung NETs are not as common as PanNETs and are mostly encountered in MEN1 syndrome and include typical and atypical lung carcinoids. Early detection of PanNETs and LNETs related to inherited syndromes is crucial, and specific follow-up protocols need to be employed to optimize diagnosis and management. Genetic screening is recommended in childhood, and diagnostic screening starts often in adolescence, even in asymptomatic mutation carriers. Optimal management and therapeutic decisions should be made in the context of a multidisciplinary team in specialized centers, whereas specific biomarkers aiming to identify patients denoted to follow a more aggressive course need to be developed. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aims to improve the preoperative classification of nerve sheath tumors using radiomics, a method that extracts quantitative data from medical images. By analyzing MRI scans, we seek to develop a more accurate way to distinguish between different types of nerve sheath tumors before surgery. Our findings could lead to better treatment planning and outcomes for patients with these tumors. This research has the potential to enhance the diagnostic process and contribute to more personalized care for individuals with nerve sheath tumors, ultimately benefiting the medical community and patients alike. Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft-tissue tumors prevalent in neurofibromatosis type 1 (NF1) patients, posing a significant risk of metastasis and recurrence. Current magnetic resonance imaging (MRI) imaging lacks decisiveness in distinguishing benign peripheral nerve sheath tumors (BPNSTs) and MPNSTs, necessitating invasive biopsies. This study aims to develop a radiomics model using quantitative imaging features and machine learning to distinguish MPNSTs from BPNSTs. Clinical data and MRIs from MPNST and BPNST patients (2000–2019) were collected at a tertiary sarcoma referral center. Lesions were manually and semi-automatically segmented on MRI scans, and radiomics features were extracted using the Workflow for Optimal Radiomics Classification (WORC) algorithm, employing automated machine learning. The evaluation was conducted using a 100× random-split cross-validation. A total of 35 MPNSTs and 74 BPNSTs were included. The T1-weighted (T1w) MRI radiomics model outperformed others with an area under the curve (AUC) of 0.71. The incorporation of additional MRI scans did not enhance performance. Combining T1w MRI with clinical features achieved an AUC of 0.74. Experienced radiologists achieved AUCs of 0.75 and 0.66, respectively. Radiomics based on T1w MRI scans and clinical features show some ability to distinguish MPNSTs from BPNSTs, potentially aiding in the management of these tumors. [ABSTRACT FROM AUTHOR]

MEK inhibitors (MEKi) represent innovative and promising treatments for managing manifestations of neurofibromatosis type 1 (NF1). To mitigate potential ophthalmic side effects, such as MEKi-associated retinopathy (MEKAR), patients undergoing MEKi therapy routinely receive ophthalmology evaluations. Our study aims to assess the necessity of this regular screening within a predominantly pediatric NF1 population by examining the occurrence of ocular adverse events (OAE). A retrospective study evaluated 45 NF1 patients receiving MEKi. Inclusion criteria included baseline and follow-up examinations following the initiation of MEKi therapy. At each assessment, a comprehensive eye evaluation was performed, comprising a dilated fundus examination, ocular coherence tomography of the macula and nerve fiber layer, and Humphrey visual field testing. Twenty-six patients, with an average age of 13 years (range 2–23 years) and an average follow-up duration of 413 days were included in the analysis. Three different MEKi were used: selumetinib (77%), trametinib (23%), and mirdametinib (4%). None of the patients experienced retinopathy at any point during the study. Some patients had pre-existing optic neuropathies (27%), but no instances of nerve changes occurred after commencing MEKi therapy. Four patients (15%) exhibited symptoms of dry eye, all of which were effectively managed with topical lubrication. [ABSTRACT FROM AUTHOR]

Aim of the report: Brooke–Spiegler syndrome (BSS) is a rare autosomal dominant disease characterized by the growth of cylindromas, spiradenomas, trichoepitheliomas, or their combination. These neoplasms usually begin in the second decade and progressively increase in number and size over the years. Diagnosis necessitates consideration of family history, clinical examination, histological findings, and genetic analysis. The aim of this paper is to explore the clinical overlap between Brooke–Spiegler syndrome (BSS) and neurofibromatosis type 1 (NF1). We aim to highlight the challenges associated with their differential diagnosis and emphasize the lack of standardized diagnostic criteria and treatment approaches. Case presentation: Hereby, we introduce the case of a 28-year-old male referred for suspicion of neurofibromatosis type 1 (NF1) who initially declined the recommended surgical excision for a scalp mass. After four years, he returned with larger masses of the scalp, and underwent excision of multiple masses, revealing cylindromas, spiradenomas, and spiradenocylindromas. Family history reported similar tumors in his father, who was also diagnosed with NF1 for the presence of multiple subcutaneous lesions on the scalp. Clinical overlap led to a genetic consultation, but testing for CYLD mutations yielded no significant variations. Despite this, the strong family history and consistent findings led to a revised diagnosis of Brooke–Spiegler syndrome, correcting the initial misdiagnosis of NF1 syndrome. Conclusions: Thanks to the evolving landscape of BSS research over the past two decades, its molecular underpinnings, clinical presentation, and histopathological features are now clearer. However, a thorough family history assessment is mandatory when BSS is suspected. It is our belief that a multidisciplinary approach and cooperation between specialists are essential when dealing with BSS. By sharing this case, we hope to underscore the importance of considering BSS as a differential diagnosis, especially in cases with atypical presentations or overlapping features with other syndromes like NF1. [ABSTRACT FROM AUTHOR]

Neurofibromatosis 1 (NF1) is a multisymptomatic disorder with highly variable presentations, which include short stature, susceptibility to formation of the characteristic benign tumors known as neurofibromas, intense freckling and skin discoloration, and cognitive deficits, which characterize most children with the condition. Attention deficits and Autism Spectrum manifestations augment the compromised learning presented by most patients, leading to behavioral problems and school failure, while fragmented sleep contributes to chronic fatigue and poor quality of life. Neurofibromin (Nf1) is present ubiquitously during human development and postnatally in most neuronal, oligodendrocyte, and Schwann cells. Evidence largely from animal models including Drosophila suggests that the symptomatic variability may reflect distinct cell-type-specific functions of the protein, which emerge upon its loss, or mutations affecting the different functional domains of the protein. This review summarizes the contributions of Drosophila in modeling multiple NF1 manifestations, addressing hypotheses regarding the cell-type-specific functions of the protein and exploring the molecular pathways affected upon loss of the highly conserved fly homolog dNf1. Collectively, work in this model not only has efficiently and expediently modelled multiple aspects of the condition and increased understanding of its behavioral manifestations, but also has led to pharmaceutical strategies towards their amelioration. [ABSTRACT FROM AUTHOR]

S100 protein expression levels and neurofibromatosis type 2 (NF-2) mutations result in different disease courses in meningiomas. This study aimed to investigate non-invasive biomarkers of NF-2 copy number loss and S100 protein expression in meningiomas using morphological, radiomics, and deep learning-based features of susceptibility-weighted MRI (SWI). This retrospective study included 99 patients with S100 protein expression data and 92 patients with NF-2 copy number loss information. Preoperative cranial MRI was conducted using a 3T clinical MR scanner. Tumor volumes were segmented on fluid-attenuated inversion recovery (FLAIR) and subsequent registration of FLAIR to high-resolution SWI was performed. First-order textural features of SWI were extracted and assessed using Pyradiomics. Morphological features, including the tumor growth pattern, peritumoral edema, sinus invasion, hyperostosis, bone destruction, and intratumoral calcification, were semi-quantitatively assessed. Mann–Whitney U tests were utilized to assess the differences in the SWI features of meningiomas with and without S100 protein expression or NF-2 copy number loss. A logistic regression analysis was used to examine the relationship between these features and the respective subgroups. Additionally, a convolutional neural network (CNN) was used to extract hierarchical features of SWI, which were subsequently employed in a light gradient boosting machine classifier to predict the NF-2 copy number loss and S100 protein expression. NF-2 copy number loss was associated with a higher risk of developing high-grade tumors. Additionally, elevated signal intensity and a decrease in entropy within the tumoral region on SWI were observed in meningiomas with S100 protein expression. On the other hand, NF-2 copy number loss was associated with lower SWI signal intensity, a growth pattern described as "en plaque", and the presence of calcification within the tumor. The logistic regression model achieved an accuracy of 0.59 for predicting NF-2 copy number loss and an accuracy of 0.70 for identifying S100 protein expression. Deep learning features demonstrated a strong predictive capability for S100 protein expression (AUC = 0.85 ± 0.06) and had reasonable success in identifying NF-2 copy number loss (AUC = 0.74 ± 0.05). In conclusion, SWI showed promise in identifying NF-2 copy number loss and S100 protein expression by revealing neovascularization and microcalcification characteristics in meningiomas. [ABSTRACT FROM AUTHOR]

Background: Plexiform neurofibromas (pNFs) are benign neoplasms, primarily originating from Schwann cells, posing challenges in patients with type 1 neurofibromatosis (NF1) due to pain, disfigurement, compression of vital structures and potential for malignancy. Selumetinib, a MEK1/2 inhibitor, has shown promising results in treating inoperable pNFs, with clinical trials demonstrating tumor volume reduction and improved patient-reported outcomes. Despite its efficacy, dermatologic toxicities may impact the quality of life and treatment adherence. Evaluating the frequency and spectrum of such effects is crucial for effective management. Methods: In a four-year retrospective and prospective study, pediatric NF1 patients with symptomatic, inoperable plexiform neurofibromas (pNFs) were treated with selumetinib. Eligibility criteria included significant morbidity, pNF size exceeding 3 cm or surgical inoperability, and performance status >70%. Hematological, liver, lung and cardiac assessments established baseline health. Selumetinib, orally administered at 25 mg/m2 twice, was administered for two years unless a response warranting extension occurred. Cutaneous AEs were documented and graded by severity according to CTCAE v5.0, with evaluations every three to six months. The impact on symptoms and pNF size was systematically recorded, and biopsies characterized histopathological features in those patients requiring surgery. Results: Twenty patients were enrolled, with an average age at therapy initiation of 11.6 years. Cutaneous side effects were common, with all patients experiencing at least one and a median of two per patient. Xerosis, paronychia and acneiform rash were prevalent. Notably, pre-pubertal individuals were more susceptible to xerosis. Acneiform rash had a higher incidence in older patients and those with skin phototypes II and III. Successful management involved tailored approaches, such as clindamycin for acneiform rash and topical agents for paronychia. Hair abnormalities, including color changes and thinning, occurred, with female patients at higher risk for the latter. Paronychia presented challenges, necessitating various interventions, including surgical approaches. AEs led to treatment suspension in 20% of patients, with tumor rebound observed in 75%. Conclusions: According to our experience, successful management of selumetinib-induced cutaneous AEs requires tailored strategies including surgery. AEs might indirectly determine pNF regrowth due to therapy suspension. We thus emphasize the pivotal role of addressing cutaneous reactions for effective selumetinib management in pediatric patients. [ABSTRACT FROM AUTHOR]

Simple Summary: Neurofibromatosis Type 1 is an inherited tumour predisposition syndrome with a varied clinical phenotype. Long-term monitoring through imaging is inconsistent and varies in high- and low-income countries. Implementation of a clinical practice guideline through a multidisciplinary clinic is instrumental to the care of adult Neurofibromatosis Type 1 patients. This systematic review aims to evaluate the association between a country's socioeconomic status and diagnostic modalities and strategies used for adult Neurofibromatosis Type 1 patients. Our results show multiple imaging modalities are used in high-income countries; however, there is limited use in low-income countries. The two most common diagnostic modalities used in developed countries are WB MRI and FDG PET/CT. Background: Neurofibromatosis Type 1 is an autosomal dominant tumour-predisposition condition commonly diagnosed in childhood and fully penetrant by adulthood. Long-term monitoring through imaging is inconsistent and varies between high- and low-income countries. Implementation of a clinical practice guideline through a multidisciplinary clinic is instrumental to the care of adult Neurofibromatosis Type 1 patients. We aim to systematically review international diagnostic modalities and strategies to evaluate any association between a country's socioeconomic status and diagnostic modalities or strategies used for Neurofibromatosis Type 1 patients. Methods: We searched PubMed, Embase, Web of Science, and Cochrane. Relevant clinical information on the surveillance of adult Neurofibromatosis Type 1 patients worldwide was reviewed, extracted, and synthesised. Results: We identified 51 papers reporting on 7724 individuals. Multiple imaging modalities are actively employed in high-income and upper-middle-income countries for surveying adult Neurofibromatosis Type 1 patients. We did not find any relevant papers from low- and middle-income countries. Conclusions: This systematic review suggests that there is robust data on diagnostic modalities for adult Neurofibromatosis Type 1 patients in high-income countries, but not for low- and middle-income countries. There is a lack of data on consolidated diagnostic strategies from both high- and low-income countries. Efforts should be made to publish data on usual clinical practice in low- and middle-income countries to develop clinical practice guidelines describing best medical practice to fit a local context. [ABSTRACT FROM AUTHOR]

Background: Neurofibromatosis Type 1 (NF1) is a genetic autosomal dominant disorder that affects both the central and peripheral nervous systems. Children and adolescents with NF1 commonly experience neuropsychological, motor, and behavioral deficits. The cognitive profile hallmark of this disorder includes visuospatial and executive function impairments. These cognitive disorders may persist into adulthood. This study aims to analyze previous research studies that have described cognitive dysfunctions in adults with NF1. The purpose of this analysis is to review the neuropsychological and psychological assessment methods used. Methods: A total of 327 articles were identified based on the search terms in their titles and abstracts. The evaluation was conducted by scrutinizing each article's title, abstract, and text. Results: Only 16 articles were found to be eligible for inclusion based on the pre-defined criteria. The selected studies primarily focus on the development of diagnostic protocols for individuals with NF1. Conclusions: The management of NF1 disease requires a multidisciplinary approach to address symptoms, preserve neurological functions, and ensure the best possible quality of life. However, cognitive impairment can negatively affect psychological well-being. This study suggested that cognitive functions in NF1 patients were not tested using specific measures, but rather were evaluated through intelligence scales. Additionally, the findings revealed that there is no standardized neuropsychological assessment for adults with NF1. To address this gap, it would be helpful to create a specific neuropsychological battery to study cognitive function in NF1 patients during clinical studies. This battery could also serve as a tool to design models for cognitive rehabilitation by using reliable and sensitive measures of cognitive outcomes. [ABSTRACT FROM AUTHOR]

Simple Summary: In this review, we explore how interactions between tumorigenic Schwann cells and infiltrating immune cells shape the development and malignant transformation of peripheral nerve sheath tumors in neurofibromatosis type 1. We summarize the current state of the field and address key knowledge gaps surrounding the impact of neurofibromin haploinsufficiency on immune cell function, as well as the impact of Schwann cell lineage states on immune cell recruitment and activation within the tumor microenvironment. Furthermore, we discuss emerging evidence suggesting a dueling role of the immune system in promoting benign tumor initiation while potentially restraining malignant outgrowth. Finally, we highlight the potential implications of these findings and suggest future directions for research relevant to the diagnosis, risk-assessment, and treatment of peripheral nerve sheath tumors, utilizing immunomodulatory therapeutics. Neurofibromatosis type 1 (NF1) is a common genetic disorder resulting in the development of both benign and malignant tumors of the peripheral nervous system. NF1 is caused by germline pathogenic variants or deletions of the NF1 tumor suppressor gene, which encodes the protein neurofibromin that functions as negative regulator of p21 RAS. Loss of NF1 heterozygosity in Schwann cells (SCs), the cells of origin for these nerve sheath-derived tumors, leads to the formation of plexiform neurofibromas (PNF)—benign yet complex neoplasms involving multiple nerve fascicles and comprised of a myriad of infiltrating stromal and immune cells. PNF development and progression are shaped by dynamic interactions between SCs and immune cells, including mast cells, macrophages, and T cells. In this review, we explore the current state of the field and critical knowledge gaps regarding the role of NF1(Nf1) haploinsufficiency on immune cell function, as well as the putative impact of Schwann cell lineage states on immune cell recruitment and function within the tumor field. Furthermore, we review emerging evidence suggesting a dueling role of Nf1+/- immune cells along the neurofibroma to MPNST continuum, on one hand propitiating PNF initiation, while on the other, potentially impeding the malignant transformation of plexiform and atypical neurofibroma precursor lesions. Finally, we underscore the potential implications of these discoveries and advocate for further research directed at illuminating the contributions of various immune cells subsets in discrete stages of tumor initiation, progression, and malignant transformation to facilitate the discovery and translation of innovative diagnostic and therapeutic approaches to transform risk-adapted care. [ABSTRACT FROM AUTHOR]

Objective: Vertebro-vertebral arteriovenous fistulae (VVFs) are a rare disorder characterized by a direct shunt between the extracranial vertebral artery and the veins of the vertebral venous plexus. This study aims to comprehensively review the characteristics and outcomes of endovascular treatments for VVFs at our center. Methods: A retrospective review was conducted on 14 patients diagnosed with a VVF who underwent endovascular treatment at Siriraj Hospital from January 2000 to January 2023. The study assessed patient demographics, presentation, fistula location, treatment strategies, endovascular techniques employed, and treatment outcomes. Results: Among the 14 patients, 11 (78.6%) were female, with an age range from 25 to 79 years (median: 50 years). Spontaneous VVFs were observed in 64.3% of the cases, including three associated with neurofibromatosis type 1 (NF-1). Iatrogenic injury accounted for two cases, and three patients had VVFs resulting from traffic accidents. A pulsatile neck mass and tinnitus, with or without neurological deficits, were common presenting symptoms. Active bleeding was observed in three cases with vascular injury, while unilateral proptosis, congestive heart failure, and incidental findings each presented in one patient. All the VVFs were successfully obliterated without major treatment complications. Parent vessel sacrifice was performed in 85.7% of the cases, while vertebral artery preservation was achieved in the remaining two patients. Embolic materials included detachable balloons, detachable coils, and n-butyl cyanoacrylate (NBCA) glue. All the presenting symptoms showed improvement, and no morbidity or mortality was observed. Conclusions: Endovascular embolization is a feasible and effective approach for achieving complete VVF obliteration with safety. Parent artery sacrifice should not be reluctantly performed, particularly when adequate collateral circulation is demonstrated. [ABSTRACT FROM AUTHOR]

Simple Summary: Most neurofibromatosis type 1 (NF1) patients present with neurological issues in parallel with abnormal brain white matter and myelin. Although links for NF1 neuropathophysiology and abnormal myelin were proposed long ago, no current data can openly support or refute this idea. Various studies suggest that Nf1 mutations affect myelin biology and function, but any impact on learning/memory remains unclear. Here, we show that mice with an Nf1 mutation induced in adult myelinating cells present learning, but not memory, issues in a voluntary fine motor skill test, the complex wheel (CW). The specific parameters shaping CW learning curves are differentially impacted in an Nf1 mutation dose- and gender-dependent manner and are responsive to nitric oxide modulation. Fate analyses of Nf1 mutant cells support links between defective myelin and fine motor learning issues. Our results diversify the potential therapeutic targets and windows of time for NF1 treatments that restore or improve myelin function. Neurofibromatosis type 1 (NF1) is caused by mutations in the NF1 gene. The clinical presentation of NF1 includes diverse neurological issues in pediatric and adult patients, ranging from learning disabilities, motor skill issues, and attention deficit disorder, to increased risk of depression and dementia. Preclinical research suggests that abnormal neuronal signaling mediates spatial learning and attention issues in NF1; however, drugs that improve phenotypes in models show inconclusive results in clinical trials, highlighting the need for a better understanding of NF1 pathophysiology and broader therapeutic options. Most NF1 patients show abnormalities in their brain white matter (WM) and myelin, and links with NF1 neuropathophysiology have been suggested; however, no current data can clearly support or refute this idea. We reported that myelin-targeted Nf1 mutation impacts oligodendrocyte signaling, myelin ultrastructure, WM connectivity, and sensory–motor behaviors in mice; however, any impact on learning and memory remains unknown. Here, we adapted a voluntary running test—the complex wheel (CW; a wheel with unevenly spaced rungs)—to delineate fine motor skill learning curves following induction of an Nf1 mutation in pre-existing myelinating cells (pNf1 mice). We found that pNf1 mutant females experience delayed or impaired learning in the CW, while proper learning in pNf1 males is predominantly disrupted; these phenotypes add complexity to the gender-dependent learning differences in the mouse strain used. No broad differences in memory of acquired CW skills were detected in any gender, but gene-dose effects were observed at the studied time points. Finally, nitric oxide signaling regulation differentially impacted learning in wild type (WT)/pNf1, male/female mice. Our results provide evidence for fine motor skill learning issues upon induction of an Nf1 mutation in mature myelinating cells. Together with previous connectivity, cellular, and molecular analyses, these results diversify the potential treatments for neurological issues in NF1. [ABSTRACT FROM AUTHOR]

Simple Summary: Activated RAS proteins drive the proliferation and survival of many human tumors. For example, in type 1 neurofibromatosis (NF1), loss of expression of neurofibromin allows hyper-activation of RAS. Drug treatments to block activated RAS have been long sought as a rational and targeted approach to treating cancer, but numerous obstacles have been discovered. We have designed a combinatorial approach to block the maturation of RAS in cellular models of malignant peripheral nerve sheath tumors (MPNSTs) from NF1 patients. The combination of a prodrug farnesyl transferase inhibitor (FTI) that is competitive with the prenyl co-factor of the enzyme plus a low dose of lovastatin to reduce cellular pools of prenyl precursors was effective and selective in blocking the proliferation of NF1 MPNST cells in vitro and in an orthotopic xenograft on the murine sciatic nerve. This approach could also be applicable to other cancers that are driven by activated RAS. Neurofibromatosis type 1 (NF1) is a disorder in which RAS is constitutively activated due to the loss of the Ras-GTPase-activating activity of neurofibromin. RAS must be prenylated (i.e., farnesylated or geranylgeranylated) to traffic and function properly. Previous studies showed that the anti-growth properties of farnesyl monophosphate prodrug farnesyltransferase inhibitors (FTIs) on human NF1 malignant peripheral nerve sheath tumor (MPNST) cells are potentiated by co-treatment with lovastatin. Unfortunately, such prodrug FTIs have poor aqueous solubility. In this study, we synthesized a series of prodrug FTI polyamidoamine generation 4 (PAMAM G4) dendrimers that compete with farnesyl pyrophosphate for farnesyltransferase (Ftase) and assessed their effects on human NF1 MPNST S462TY cells. The prodrug 3-tert-butylfarnesyl monophosphate FTI-dendrimer (i.e., IG 2) exhibited improved aqueous solubility. Concentrations of IG 2 and lovastatin (as low as 0.1 μM) having little to no effect when used singularly synergistically suppressed cell proliferation, colony formation, and induced N-RAS, RAP1A, and RAB5A deprenylation when used in combination. Combinational treatment had no additive or synergistic effects on the proliferation/viability of immortalized normal rat Schwann cells, primary rat hepatocytes, or normal human mammary epithelial MCF10A cells. Combinational, but not singular, in vivo treatment markedly suppressed the growth of S462TY xenografts established in the sciatic nerves of immune-deficient mice. Hence, prodrug farnesyl monophosphate FTIs can be rendered water-soluble by conjugation to PAMAM G4 dendrimers and exhibit potent anti-tumor activity when combined with clinically achievable statin concentrations. [ABSTRACT FROM AUTHOR]

Simple Summary: Neurofibromatosis 1 (NF1) is a genetic disorder that predisposes patients to developing nerve sheath tumors that are difficult to treat. There is currently just one drug approved for the treatment of NF1-related inoperable plexiform neurofibromas (for a limited patient population), highlighting the need for further drug discovery in this field. High-throughput screening data are used to guide drug development, but identifying and selecting promising targets can be complex. The aim of our study is to improve the value of high-throughput screening data by combining potency and effectiveness into single-value indices (S, ΔS, and ΔS mean), which are used to assess and rank drug sensitivity and drug resistance in cells exposed to potential therapeutic drugs. Our approach with S indices was applied to cell lines derived from plexiform neurofibromas of patients with NF1 gene mutations. The use of S indices provides valuable additional and independent information for discriminating among candidate compounds for follow-up pre-clinical evaluations. Background: Neurofibromatosis type 1 (NF1) is a genetic disorder characterized by heterozygous germline NF1 gene mutations that predispose patients to developing plexiform neurofibromas, which are benign but often disfiguring tumors of the peripheral nerve sheath induced by loss of heterozygosity at the NF1 locus. These can progress to malignant peripheral nerve sheath tumors (MPNSTs). There are no approved drug treatments for adults with NF1-related inoperable plexiform neurofibromas, and only one drug (selumetinib), which is an FDA-approved targeted therapy for the treatment of symptomatic pediatric plexiform neurofibromas, highlighting the need for additional drug screening and development. In high-throughput screening, the effectiveness of drugs against cell lines is often assessed by measuring in vitro potency (AC50) or the area under the curve (AUC). However, the variability of dose–response curves across drugs and cell lines and the frequency of partial effectiveness suggest that these measures alone fail to provide a full picture of overall efficacy. Methods: Using concentration–response data, we combined response effectiveness (EFF) and potency (AC50) into (a) a score characterizing the effect of a compound on a single cell line, S = log[EFF/AC50], and (b) a relative score, ΔS, characterizing the relative difference between a reference (e.g., non-tumor) and test (tumor) cell line. ΔS was applied to data from high-throughput screening (HTS) of a drug panel tested on NF1−/− tumor cells, using immortalized non-tumor NF1+/− cells as a reference. Results: We identified drugs with sensitivity, targeting expected pathways, such as MAPK-ERK and PI3K-AKT, as well as serotonin-related targets, among others. The ΔS technique used here, in tandem with a supplemental ΔS web tool, simplifies HTS analysis and may provide a springboard for further investigations into drug response in NF1-related cancers. The tool may also prove useful for drug development in a variety of other cancers. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is a rare disease, affecting around 1 in 3500 individuals in the general population. The rarity of the disease contributes to the scarcity of the available diagnostic and therapeutic approaches. Multispectral imaging is a non-invasive imaging method that shows promise in the diagnosis of various skin diseases. The device utilized for the present study consisted of four sets of narrow-band LEDs, including 526 nm, 663 nm, and 964 nm for diffuse reflectance imaging and 405 nm LEDs, filtered through a 515 nm long-pass filter, for autofluorescence imaging. RGB images were captured using a CMOS camera inside of the device. This paper presents the results of this multispectral skin imaging approach to distinguish the lesions in patients with NF1 from other more common benign skin lesions. The results show that the method provides a potential novel approach to distinguish NF1 lesions from other benign skin lesions. [ABSTRACT FROM AUTHOR]

In this paper, the authors present a clinical picture of the diagnosis and current treatment regimens of optic pathway glioma in the pediatric population, with an emphasis on the role of an ophthalmic diagnosis in the differentiation and monitoring of lesions. Glioma is the most common optic nerve tumor in children. Material: Articles in PubMed, Scholar and Website were reviewed, taking into account current standards of management related to sporadic or NF1-related optic glioma, epidemiology, location, course of the disease, clinical manifestations, histological types of the tumor, genetic predisposition, diagnostic ophthalmic tests currently applicable in therapeutic monitoring of the tumor, neurological diagnosis, therapeutic management and prognosis. The importance of current screening recommendations, in line with standards, was emphasized. Results: Glioma occurs in children most often in the first decade of life. Initially, they may be asymptomatic, and clinically ophthalmic changes are associated with the organ of vision or with systemic changes. Gliomas associated with the NF1 mutation have a better prognosis for sporadic gliomas. Diagnosis includes radiological imaging methods/MRI/ophthalmology/OCT and visual acuity log MAR assessment. The basis of treatment is clinical observation. In the case of disease progression, surgical treatment, chemotherapy and targeted therapy are used. Conclusion: Further research into novel techniques for detecting gliomas would allow for early monitoring of the disease. [ABSTRACT FROM AUTHOR]

Simple Summary: Neurofibromatosis type 1 is a common autosomal dominant inherited condition, with variable phenotype among affected individuals. Abnormalities of the cerebral vasculature are an acknowledged but poorly understood complication, leading to high morbidity and mortality for individuals with neurofibromatosis type 1. The current review discusses the different types of cerebral vasculopathy, the clinical presentation and diagnosis, followed by proposed pathogenesis. Medical and surgical management options are presented, with a goal to prevent lasting neurologic injury. Cerebrovascular abnormalities are a severe and often underrecognized complication of childhood neurofibromatosis type 1 (NF1). There are no prospective studies of cerebral vasculopathy in NF1; thus, the estimated frequency of vasculopathy varies between studies. The data is difficult to interpret due to the retrospective data collection and variability in whether imaging is done based on screening/surveillance or due to acute neurologic symptoms. The prevalent NF1-associated cerebral vasculopathy is moyamoya syndrome (MMS). Vascular changes can present without symptoms or with acute TIA or stroke-like symptoms or a range of progressive neurologic deficits. Advanced imaging may enhance sensitivity of neuroimaging in children. Medical and/or surgical interventions may prevent short- and long-term complications. Challenges for establishment of a screening protocol for cerebral vasculopathy in children with NF1 include the relatively large number of patients with NF1, the potential need for sedation to achieve quality imaging and the broad age range at time of detection for cerebral vascular changes. The goal of this review is to present the epidemiology, clinical presentation, imaging features and medical/surgical management of cerebral arteriopathies in children with NF1. [ABSTRACT FROM AUTHOR]

Optic pathway glioma (OPG) is one of the causes of pediatric visual impairment. Unfortunately, there is as yet no cure for such a disease. Understanding the underlying mechanisms and the potential therapeutic strategies may help to delay the progression of OPG and rescue the visual morbidities. Here, we provide an overview of preclinical OPG studies and the regulatory pathways controlling OPG pathophysiology. We next discuss the role of microenvironmental cells (neurons, T cells, and tumor-associated microglia and macrophages) in OPG development. Last, we provide insight into potential therapeutic strategies for treating OPG and promoting axon regeneration. [ABSTRACT FROM AUTHOR]

Simple Summary: Neurofibromatosis type 1 (Nf1) is a genetically determined neurodevelopmental disorder and tumor syndrome with an incidence of approximately 1/3000 live births. It is caused by loss of function mutations in the neurofibromin gene (Nf1) and is estimated to affect 100,000 people in the US. Approximately 50% of the patients inherited the condition in an autosomal dominant pattern; the remaining 50% are the result of de novo mutations. Behavioral alterations and cognitive deficits have been found in 50–70% of children with Nf1. These behavioral alterations and cognitive deficits include specific problems with attention, visual perception, language, learning, attention, and executive function. Inhibition of the anaplastic lymphoma kinase (Alk), a kinase which is negatively regulated by neurofibromin, allows for testing the hypothesis that this inhibition may be therapeutically beneficial in Nf1. In this review, we discuss this area of research and directions for the development of alternative therapeutic strategies to inhibit Alk. Neurofibromatosis type 1 (Nf1) is a neurodevelopmental disorder and tumor syndrome caused by loss of function mutations in the neurofibromin gene (Nf1) and is estimated to affect 100,000 people in the US. Behavioral alterations and cognitive deficits have been found in 50–70% of children with Nf1 and include specific problems with attention, visual perception, language, learning, attention, and executive function. These behavioral alterations and cognitive deficits are observed in the absence of tumors or macroscopic structural abnormalities in the central nervous system. No effective treatments for the behavioral and cognitive disabilities of Nf1 exist. Inhibition of the anaplastic lymphoma kinase (Alk), a kinase which is negatively regulated by neurofibromin, allows for testing the hypothesis that this inhibition may be therapeutically beneficial in Nf1. In this review, we discuss this area of research and directions for the development of alternative therapeutic strategies to inhibit Alk. Even if the incidence of adverse reactions of currently available Alk inhibitors was reduced to half the dose, we anticipate that a long-term treatment would pose challenges for efficacy, safety, and tolerability. Therefore, future efforts are warranted to investigate alternative, potentially less toxic and more specific strategies to inhibit Alk function. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is a clinically heterogeneous neurocutaneous disorder inherited in autosomal dominant manner. Approximately 5–10% of the cases are caused by NF1 microdeletions involving the NF1 gene and its flanking regions. Microdeletions, which lead to more severe clinical manifestations, can be subclassified into four different types (type 1, 2, 3 and atypical) according to their size, the genomic location of the breakpoints and the number of genes included within the deletion. Besides the prominent hallmarks of NF1, patients with NF1 microdeletions frequently exhibit specific additional clinical manifestations like dysmorphic facial features, macrocephaly, overgrowth, global developmental delay, cognitive disability and an increased risk of malignancies. It is important to identify the genes co-deleted with NF1, because they are likely to have an effect on the clinical manifestation. Multiplex ligation-dependent probe amplification (MLPA) and microarray analysis are the primary techniques for the investigation of NF1 microdeletions. However, based on previous research, optical genome mapping (OGM) could also serve as an alternative method to identify copy number variations (CNVs). Here, we present a case with NF1 microdeletion identified by means of OGM and demonstrate that this novel technology is a suitable tool for the identification and classification of the NF1 microdeletions. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is a rare inherited neurocutaneous disorder with a major impact on the skin, nervous system and eyes. The ocular diagnostic hallmarks of this disease include iris Lisch nodules, ocular and eyelid neurofibromas, eyelid café-au-lait spots and optic pathway gliomas (OPGs). In the last years, new manifestations have been identified in the ocular district in NF1 including choroidal abnormalities (CAs), hyperpigmented spots (HSs) and retinal vascular abnormalities (RVAs). Recent advances in multi-modality imaging in ophthalmology have allowed for the improved characterization of these clinical signs. Accordingly, CAs, easily detectable as bright patchy nodules on near-infrared imaging, have recently been added to the revised diagnostic criteria for NF1 due to their high specificity and sensitivity. Furthermore, subclinical alterations of the visual pathways, regardless of the presence of OPGs, have been recently described in NF1, with a primary role of neurofibromin in the myelination process. In this paper, we reviewed the latest progress in the understanding of choroidal and retinal abnormalities in NF1 patients. The clinical significance of the recently revised diagnostic criteria for NF1 is discussed along with new updates in molecular diagnosis. New insights into NF1-related neuro-ophthalmic manifestations are also provided based on electrophysiological and optical coherence tomography (OCT) studies. [ABSTRACT FROM AUTHOR]

Background: Statins, apart from their plasma-cholesterol-lowering ability, exert several pleiotropic effects, making them a potential treatment for other diseases. Animal studies have showed that statins, through the inhibition of 3-hydroxy-3-methylglutaryl coenzyme A reductase, can affect the Ras/MAPK pathway, thus providing impetus to examine the efficacy of statins in the pediatric population with neurofibromatosis type 1 (NF1). We aimed to systematically address all relevant evidence of statin treatment in children with NF1. Methods: We searched PubMed and Cochrane Library resources up to 2 June 2023 for randomized controlled trials (RCTs) written in English and evaluating statins versus placebo in children with NF1 (PROSPERO registration number: CRD42023439424). Results: Seven RCTs were suitable to be included in this qualitative synthesis, with a total participation of 336 children with NF1. The duration of the studies ranged from 12 to 52 weeks. The mean age of the pediatric population was 10.9 years old. Three studies investigated the role of simvastatin, while four studies examined lovastatin. According to our analysis, neither simvastatin nor lovastatin improved cognitive function, full-scale intelligence, school performance, attention problems, or internalizing behavioral problems when compared with placebo in children with NF1. Statins were well tolerated in all included RCTs. Conclusion: Although safe, current evidence demonstrates that statins exert no beneficial effect in cognitive function and behavioral problems in children with NF1. [ABSTRACT FROM AUTHOR]

Simple Summary: Difficulties in sensory processing are often found in neurodevelopmental disorders and can significantly impact how a child responds to and functions within their environment. Studies examining sensory processing in children with neurofibromatosis type 1 (NF1) are sparse. This cross-sectional study aims to address this gap by examining parent-reported sensory processing in a sample of 152 children with NF1. Approximately 61% of children with NF1 displayed differences in how they respond to sensory stimuli when compared to a typically developing control group. These difficulties were seen equally across ages and sex and were found to be associated with a higher degree of autistic behaviors, ADHD symptoms, lower adaptive skills, poorer social skills, and increased anxiety and affective symptoms. The results highlight the importance of accommodating multisensory processing difficulties at home and school when deciding how to support a child with NF1 across environments. Despite the evidence of elevated autistic behaviors and co-occurring neurodevelopmental difficulties in many children with neurofibromatosis type 1 (NF1), we have a limited understanding of the sensory processing challenges that may occur with the condition. This study examined the sensory profile of children and adolescents with NF1 and investigated the relationships between the sensory profiles and patient characteristics and neuropsychological functioning. The parent/caregivers of 152 children with NF1 and 96 typically developing children completed the Sensory Profile 2 (SP2), along with standardized questionnaires assessing autistic behaviors, ADHD symptoms, internalizing symptoms, adaptive functioning, and social skills. Intellectual functioning was also assessed. The SP2 data indicated elevated sensory processing problems in children with NF1 compared to typically developing children. Over 40% of children with NF1 displayed differences in sensory registration (missing sensory input) and were unusually sensitive to and unusually avoidant of sensory stimuli. Sixty percent of children with NF1 displayed difficulties in one or more sensory modalities. Elevated autistic behaviors and ADHD symptoms were associated with more severe sensory processing difficulties. This first detailed assessment of sensory processing, alongside other clinical features, in a relatively large cohort of children and adolescents with NF1 demonstrates the relationships between sensory processing differences and adaptive skills and behavior, as well as psychological well-being. Our characterization of the sensory profile within a genetic syndrome may help facilitate more targeted interventions to support overall functioning. [ABSTRACT FROM AUTHOR]

The induced membrane technique is an innovative approach for repairing critical bone defects and has been applied recently in patients with congenital pseudarthrosis of the tibia (CPT). CPT is frequently associated with neurofibromatosis type 1 (NF1). Here, we briefly describe the clinical results of the induced membrane technique in NF1-deficient patients with CPT and in an animal model of CPT. Furthermore, we discuss the hypotheses used to explain inconsistent outcomes for the induced membrane technique in CPT–especially when associated with NF1. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 is a rare autosomal dominant genetic disorder, with up to 50% of patients clinically displaying skeletal defects. Currently, the pathogenesis of bone disorders in NF1 patients is unclear, and there are no effective preventive and treatment measures. In this study, we found that knockout of the NF1 gene reduced cAMP levels and osteogenic differentiation in an osteoblast model, and icariin activated the cAMP/PKA/CREB pathway to promote osteoblast differentiation of the NF1 gene knockout cell model by increasing intracellular cAMP levels. The PKA selective inhibitor H89 significantly impaired the stimulatory effect of icariin on osteogenesis in the NF1 cell model. In this study, an osteoblast model of NF1 was successfully constructed, and icariin was applied to the cell model for the first time. The results will help to elucidate the molecular mechanism of NF1 bone disease and provide new ideas for the clinical prevention and treatment of NF1 bone disease and drug development in the future. [ABSTRACT FROM AUTHOR]

Simple Summary: Most melanoma patients have non-overlapping "driver" mutations in either BRAF, NRAS, or NF1 genes based on Next-Gen sequencing. Other overlapping genetic changes, termed "passenger mutations" may also be identified. The impact of these mutations on cancer immunotherapy outcome is currently not well understood. We evaluated the outcome of checkpoint inhibitor-based immunotherapy in 73 patients. Rare patients with BRAF fusion genes or internal rearrangements had a significantly reduced progression-free and overall survival. No other "driver" or "passenger" mutations appeared to influence outcome in a multivariate analysis. The strongest predictor of long-term survival in our study appeared to be development of a complete response as assessed at 12 months from the start of treatment. Background: Non-overlapping somatic mutations in BRAF, NRAS, or NF1 genes occur in 85% of metastatic melanoma patients. It is not known whether these mutations affect immunotherapy outcome. Materials and methods: Next-Gen sequencing of 324 oncogenes was performed in 73 metastatic melanoma patients. A retrospective review of immunotherapy outcome was performed. Results: BRAF fusions/internal rearrangements, BRAF V600E, NRAS, NF1 mutations, and triple-negative genotypes occurred in 6.9%, 30.1%, 17.8%, 32.9%, and 12.3% of patients, respectively. Median potential follow-up was 41.0 months. Patients with BRAF fusion/rearrangement had decreased progression-free and overall survival (p = 0.015). The other genotypes each had similar progression-free and overall survival. Patients who achieved a complete best objective response at 12 months (n = 36, 49.3%) were found to have significantly improved survival compared those who failed to achieve remissions (n = 37, 50.7%, p < 0.001). Conclusions: The most important determinant of long-term survival was achievement of a complete response by 12 months following immunotherapy. PR and SD were not a stable type of response and generally resulted in progression and death from melanoma. Rare patients with BRAF fusions or rearrangements had decreased progression-free and overall survival following initial immunotherapy. Other BRAF, NRAS, or NF1 mutations were not associated with significant differences in outcome. [ABSTRACT FROM AUTHOR]

Simple Summary: Mobile applications are an effective method to promote self-monitoring of various diseases and disorders. However, maintaining active engagement and adherence in mobile applications can be difficult. We found that using an incentive based system increased an individual's usage of the mobile application in multiple areas (e.g., number of articles read, number of goals set). In keeping individuals engaged in the mobile application they were more apt to review and use the content to learn how to self-monitor their pain symptoms and reduce their chronic pain. We suggest implementing incentive based systems to increase engagement and adherence for mobile applications. Introduction: Neurofibromatosis Type 1 (NF1) is an autosomal dominant genetic condition in which chronic pain is a predominant issue. Given the rarity of the disease, there are limited psychosocial treatments for individuals with NF1 suffering with chronic pain. Using mobile applications can facilitate psychosocial treatments; however, there are consistent issues with engagement. Utilizing a mixed methodology, the current study evaluated the customized iCanCope mobile application for NF1 on increasing engagement through the usage of contingency management. Methods: A mixed methods study from a subset of data coming from a randomized clinical trial that occurred from January 2021 to August 2022 was undertaken. Two groups (iCC and iCC + CM) were exposed to the customized iCanCope mobile application in which engagement data were captured in real-time with daily check-ins for interference, sleep, mood, physical activity, energy levels, goal setting, and accessing article content (coping strategies). Additionally, semi-structured interviews were conducted to gain insight into the participants' experience at the end of the trial. Results: Adults (N = 72) were recruited via NF patient advocacy groups. Significant differences were noted between the groups in total articles read (p = 0.002), goals achieved (p = 0.017), and goals created (p = 008). Additionally, there were significant differences observed between user-generated goals and those that were app recommended (p < 0.001). Both groups qualitatively reported positive feedback on the customized mobile application, indicating that continued usage and engagement of the mobile application were acceptable. Conclusions: Employing customized mobile applications for adults with NF1 along with contingency management can leverage self-managed pain treatments while providing auxiliary resources to this population. [ABSTRACT FROM AUTHOR]

The most common complaint among patients with vestibular schwannoma (VS) is hearing loss. This significantly affects the quality of life before, during, and after treatment for patients with VS. Untreated hearing loss in VS patients may even lead to depression and feelings of social isolation. A variety of devices are available for hearing rehabilitation for patients with vestibular schwannoma. These include contralateral routing of hearing signals (CROSs), bone-anchored hearing devices, auditory brainstem implants (ABI), and cochlear implants. In the United States, ABI is approved for patients 12 years of age and older with neurofibromatosis type 2. In the past few years, cochlear implantation has been offered simultaneously or sequentially with tumor resection or irradiation, or even to patients whose VS have been monitored with serial imaging. However, determining the functional integrity of the auditory nerve in patients with vestibular schwannoma is a challenge. This review article consists of (1) the pathophysiology of vestibular schwannoma (VS), (2) hearing loss in VS, (3) treatment of VS and associated hearing loss, (4) options for auditory rehabilitation in patients with VS with their individual benefits and limitations, and (5) challenges in hearing rehabilitation in this cohort of patients to determine auditory nerve functionality. (6) Future directions. [ABSTRACT FROM AUTHOR]

Simple Summary: Neurofibromatosis type 1 (NF1) is a genetic neurophakomatosis (neuroectodermal disorder) associated with a wide array of skin findings. The most recognizable feature is cutaneous neurofibromas; however, less common dermatologic stigmata may also occur. Currently, there are limited therapeutic options for the cutaneous manifestations of NF1. This review summarizes the dermatologic sequelae of NF1 and provides an update on emerging treatments. Appropriate care of these patients often requires interdisciplinary collaboration between neurologists, oncologists, and dermatologists, among other specialties. Increased awareness of these conditions is crucial for providing adequate care to patients with NF1. Neurofibromatosis type 1 (NF1) is an autosomal dominant tumor predisposition syndrome that increases one's risk for both benign and malignant tumors. NF1 affects every organ in the body, but the most distinctive symptoms that are often the most bothersome to patients are the cutaneous manifestations, which can be unsightly, cause pain or pruritus, and have limited therapeutic options. In an effort to increase awareness of lesser-known dermatologic associations and to promote multidisciplinary care, we conducted a narrative review to shed light on dermatologic associations of NF1 as well as emerging treatment options. Topics covered include cutaneous neurofibromas, plexiform neurofibromas, diffuse neurofibromas, distinct nodular lesions, malignant peripheral nerve sheath tumors, glomus tumors, juvenile xanthogranulomas, skin cancer, and cutaneous T-cell lymphoma. [ABSTRACT FROM AUTHOR]

Simple Summary: Limited effective therapies exist for the treatment of neurofibromatosis type 1 (NF1)-associated plexiform neurofibroma (PN). The aim of our prospective clinical trial was to evaluate the activity and safety of vinblastine and methotrexate (conventional cytotoxic chemotherapies) given on a metronomic schedule in children and young adults with NF1 and PN. Of the 23 participants evaluable for treatment outcomes and toxicities, 14 completed all protocol therapy. There were no participants that discontinued therapy due to dose-limiting toxicities. In addition, there were no participants that demonstrated a partial response. VBL/MTX was well-tolerated but did not result in objective volumetric responses. Limited therapies exist for neurofibromatosis type 1 (NF1)-associated plexiform neurofibroma (PN). For this reason, the activity of vinblastine (VBL) and methotrexate (MTX) was evaluated in children and young adults with NF1 and PN. Patients ≤ 25 years of age with progressive and/or inoperable NF1-PN received VBL 6 mg/m2 and MTX 30 mg/m2 weekly for 26 weeks, followed by every 2 weeks for 26 weeks. Objective response rate was the primary endpoint. Of 25 participants enrolled, 23 were evaluable. The median age of participants was 6.6 years (range 0.3–20.7). The most frequent toxicities were neutropenia and elevation of transaminases. On two-dimensional (2D) imaging, 20 participants (87%) had stable tumor, with a median time to progression of 41.5 months (95% confidence interval 16.9, 64.9). Two of eight participants (25%) with airway involvement demonstrated functional improvements including decreased positive pressure requirements and apnea-hypopnea index. A post hoc three-dimensional (3D) analysis of PN volumes was completed on 15 participants with amenable imaging; 7 participants (46%) had progressive disease on or by the end of therapy. VBL/MTX was well-tolerated but did not result in objective volumetric response. Furthermore, 3D volumetric analysis highlighted the lack of sensitivity of 2D imaging for PN response evaluation. [ABSTRACT FROM AUTHOR]

Next-generation sequencing technology has improved molecular genetic analysis, and many molecular genetic studies have been utilized for diagnostic classification, risk stratification, and prognosis prediction of acute lymphoblastic leukemia (ALL). Inactivation of neurofibromin or Nf1, a protein derived from the NF1 gene, causes Ras pathway regulation failure, which is related to leukemogenesis. Pathogenic variants of the NF1 gene in B-cell lineage ALL are uncommon, and in this study, we reported a pathogenic variant that is not registered in any public database. The patient diagnosed with B-cell lineage ALL had no clinical symptoms of neurofibromatosis. Studies on the biology, diagnosis, and treatment of this uncommon disease, as well as other related hematologic neoplasms, such as acute myeloid leukemia and juvenile myelomonocytic leukemia, were reviewed. Biological studies included epidemiological differences among age intervals and pathways for leukemia, such as the Ras pathway. Diagnostic studies included cytogenetic, FISH, and molecular tests for leukemia-related genes and ALL classification, such as Ph-like ALL or BCR-ABL1-like ALL. Treatment studies included pathway inhibitors and chimeric antigen cell receptor T-cells. Resistance mechanisms related to leukemia drugs were also investigated. We believe that these literature reviews will enhance medical care for the uncommon diagnosis of B-cell lineage ALL. [ABSTRACT FROM AUTHOR]

Simple Summary: Focal areas of signal intensity (FASI) are common neuro-imaging abnormalities in children with neurofibromatosis type 1 (NF1). They may confound tumor evaluations and have been associated with neurocognitive differences in some studies. Selumetinib is a MEK inhibitor recently studied in NF1-associated low-grade glioma by the Pediatric Brain Tumor Consortium (PBTC). The current study looked at the impact of selumetinib on FASI. Unlike its effect on NF1-associated LGG, selumetinib did not change the overall size of FASI in children with NF1. Background: Understanding the effect of selumetinib on FASI may help elucidate the biology, proliferative potential, and role in neurocognitive changes for these NF1-associated lesions. Methods: Patients with NF1-associated LGG and FASI treated with selumetinib on PBTC-029B were age-matched to untreated patients with NF1-associated FASI at Cincinnati Children's Hospital Medical Center. Paired bidirectional measurements were compared over time using nonparametric tests. Results: Sixteen age-matched pairs were assessed (age range: 2.8–16.9 years, 60% male). Initial FASI burden was not different between groups (median range 138.7 cm2 [88.4–182.0] for the treated subjects vs. 121.6 cm2 [79.6—181.9] for the untreated subjects; p = 0.98). Over a mean follow-up of 18.9 (±5.9) months, the LGG size consistently decreased with treatment while no consistent change among the treated or untreated FASI size was seen. At the paired time points, the median treated LGG decreased significantly more than the treated FASI (−41.3% (LGG) versus −10.7% (FASI), p = 0.006). However, there was no difference in the median size change in the treated versus untreated FASI (−10.7% (treated FASI) versus −17.9% (untreated FASI), p = 0.08). Among the treated subjects, there was no correlation between the change in LGG and FASI (r = −0.04, p = 0.88). Conclusions: Treatment with selumetinib did not affect the overall FASI size in children with NF1 treated for progressive low-grade glioma. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is one of the central nervous system's most common autosomal dominant conditions. The diagnosis is based on the clinical diagnostic criteria and/or a molecularly confirmed mutation in the NF1 gene. This study investigated the possibility of substantiating choroidal nodules as a diagnostic criterion for the disease, including patients affected with and without high myopia. A cross-sectional study was carried out in 60 eyes of 30 adult patients diagnosed with NF1. A total of 30 healthy individuals of equivalent age and sex served as control. The Spectralis HRA+OCT MultiColor (Heidelberg Engineering GmbH, Heidelberg, Germany) evaluated the presence of choroidal abnormalities with near-infrared reflectance imaging. Secondly, the presence of iridian Lisch nodules was evaluated by slit lamp examination. Near-infrared reflectance imaging showed the presence of choroidal hyperreflective nodules in 83% of the patients diagnosed with NF1, while these choroidal abnormalities were not observed in any control subject. The patients diagnosed with NF1 associated with high myopia were the only ones who did not present the characteristic choroidal disorders. Therefore, when excluding patients diagnosed with high myopia, choroidal nodules were more frequent than Lisch nodules in a statistically significant proportion. Hyperreflective nodules detected by near-infrared reflectance imaging are as regular as Lisch nodules or even significantly more frequent when excluding high myope patients. Our observation of the mutual exclusion of choroidal hyperreflective nodules and high myopia in the NF1 patients seems a novel and interesting remark. [ABSTRACT FROM AUTHOR]

Simple Summary: Neurofibromatosis type 1 and Moyamoya disease can be associated in Moyamoya syndrome (MMS), which causes cerebral arteriopathy consisting of a progressive steno-occlusion of the intracranial arteries. Here, we investigated if rare variants of RNF213, the most common genetic risk factor for Moyamoya, could act as genetic modifiers of MMS phenotype in a pediatric cohort of patients. Next-generation sequencing of NF1 and RNF213 genes was performed on genomic DNA extracted from patients' blood. We found that in MMS patients, RNF213 does not appear to modify Moyamoya occurrence risk. Rather, it is more probable that the loss of neurofibromin 1, the protein encoded by the NF1 gene, is responsible by itself for the excessive proliferation of vascular smooth muscle cells causing arterial stenosis. Further studies in larger cohorts of patients are necessary to confirm these findings and to identify other genetic factors in order to increase our understanding of MMS pathogenesis. Neurofibromatosis type 1 (NF1) is a neurocutaneous disorder caused by mutations in NF1 gene, coding for neurofibromin 1. NF1 can be associated with Moyamoya disease (MMD), and this association, typical of paediatric patients, is referred to as Moyamoya syndrome (MMS). MMD is a cerebral arteriopathy characterized by the occlusion of intracranial arteries and collateral vessel formation, which increase the risk of ischemic and hemorrhagic events. RNF213 gene mutations have been associated with MMD, so we investigated whether rare variants of RNF213 could act as genetic modifiers of MMS phenotype in a pediatric cohort of 20 MMS children, 25 children affected by isolated MMD and 47 affected only by isolated NF1. By next-generation re-sequencing (NGS) of patients' DNA and gene burden tests, we found that RNF213 seems to play a role only for MMD occurrence, while it does not appear to be involved in the increased risk of Moyamoya for MMS patients. We postulated that the loss of neurofibromin 1 can be enough for the excessive proliferation of vascular smooth muscle cells, causing Moyamoya arteriopathy associated with NF1. Further studies will be crucial to support these findings and to elucidate the possible role of other genes, enhancing our knowledge about pathogenesis and treatment of MMS. [ABSTRACT FROM AUTHOR]

To provide an effective alternative to sedation during MRI examinations in pediatric cancer and NF1 patients, the aims of the present study were to (1) exploratively evaluate a behavioral MRI training program, to (2) investigate potential moderators, as well as to (3) assess the patients' well-being over the course of the intervention. A total of n = 87 patients of the neuro-oncology unit (mean age: 6.83 years) underwent a two-step MRI preparation program, including training inside the scanner, and were recorded using a process-oriented screening. In addition to the retrospective analysis of all data, a subset of 17 patients were also analyzed prospectively. Overall, 80% of the children receiving MRI preparation underwent the MRI scan without sedation, making the success rate almost five times higher than that of a group of 18 children that opted out of the training program. Memory, attentional difficulties, and hyperactivity were significant neuropsychological moderators for successful scanning. The training was associated with favorable psychological well-being. These findings suggest that our MRI preparation could present an alternative to sedation of young patients undergoing MRI examinations as well as a promising tool for improving patients' treatment-related well-being. [ABSTRACT FROM AUTHOR]

Background: Congenital pseudoarthrosis of the tibia (CPT) remains a challenge for physicians. Several treatment options have been proposed, but the standard of care remains inconclusive. In this study, we present three patients for whom the failure of prior treatments was managed with a contralateral vascularized fibular bone graft (VFG) and an anatomic distal tibial locking plate. Methods: Between 2017 and 2021, three patients were referred for failed treatment of CPT. All patients had undergone multiple prior surgeries, including tumor excision and fixation with ring external fixators, plates, and screws. We performed radical tumor resection and reconstruction of bone defects with a VFG. The construct was fixed with an anatomic locking plate, and the patients were followed up for a mean of 45.7 months. Results: All three patients were able to obtain graft union at 19.3 weeks. At the final follow-up, all grafts achieved bony hypertrophy without evidence of bone resorption or local tumor recurrence. There was a mean leg length difference of 8.5 cm preoperatively, compared with 6.3 cm postoperatively. The average lower leg angulation was 7.4 degrees and the average ankle range of motion was 58.3 degrees. The mean VAS score was 0 and the mean AOFAS score was 88.3. No significant complications were noted. Conclusions: Implantation of a VFG and an anatomic distal tibia locking plate can be considered an option for treatment-refractory CPT. Patients can expect to achieve bone consolidation, ambulate as tolerated, and have a low complication rate. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is a genetic condition affecting 1 in 3000 individuals. Having a child with a chronic illness can introduce both practical and emotional challenges to a parental relationship. This cross-sectional study was administered to 50 parents of children with NF1, diagnosed between the ages of 1–24. Each participant was provided a 50-item self-report survey to complete during an inpatient or outpatient visit. The survey gathered information on the participants' views of the spouse/partner relationship, coping mechanisms, and elements that supported emotional connections. While the majority of parental relationships were reported to remain strong, the mean relationship quality was perceived to have decreased compared to prior to the child's diagnosis. Compassionate and open communication, shared perspective, having time alone with their partner outside of medical situations, and dyadic coping were identified as strategies that could strengthen the relationship. The identified stressors to the parental relationship during the NF1 illness trajectory can inform interventions and help guide development of a couple's intervention. The National Cancer Institute, NIH Institutional Review Board approved this study (12-C-0206). [ABSTRACT FROM AUTHOR]

Simple Summary: In the last few years, an increasing number of genotype–phenotype correlations has been described for neurofibromatosis type 1 (NF1), impacting on the clinical follow-up of patients, especially in pediatric age. The widespread use of molecular diagnosis, made easier by next generation sequencing technology, now allows very early confirmation of clinical diagnosis, even in the case of non-canonical presentation of the disorder with other overlapping conditions. Here, we review the main clinical characteristics and complications related to NF1, particularly those occurring in children. We also describe currently known genotype–phenotype associations that need to be considered because of their effect on genetic counseling and prognosis. Molecular diagnosis is today fundamental for the confirmation of doubtful clinical diagnoses, especially in the light of recently revised diagnostic criteria, and for the early identification of genotypes, albeit few, that correlate with specific phenotypes. Neurofibromatosis type 1 (NF1) is an autosomal dominant condition, with a birth incidence of approximately 1:2000–3000, caused by germline pathogenic variants in NF1, a tumor suppressor gene encoding neurofibromin, a negative regulator of the RAS/MAPK pathway. This explains why NF1 is included in the group of RASopathies and shares several clinical features with Noonan syndrome. Here, we describe the main clinical characteristics and complications associated with NF1, particularly those occurring in pediatric age. NF1 has complete penetrance and shows wide inter- and intrafamilial phenotypic variability and age-dependent appearance of manifestations. Clinical presentation and history of NF1 are multisystemic and highly unpredictable, especially in the first years of life when penetrance is still incomplete. In this scenario of extreme phenotypic variability, some genotype–phenotype associations need to be taken into consideration, as they strongly impact on genetic counseling and prognostication of the disease. We provide a synthetic review, based on the most recent literature data, of all known genotype–phenotype correlations from a genetic and clinical perspective. Molecular diagnosis is fundamental for the confirmation of doubtful clinical diagnoses, especially in the light of recently revised diagnostic criteria, and for the early identification of genotypes, albeit few, that correlate with specific phenotypes. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is an autosomal dominant condition, associated with neurocutaneous manifestations and neuropsychiatric manifestations. The present study explored the prevalence of bullying/cyberbullying behaviors and victimization behaviors in a cohort of children and adolescents with NF1. Possible gender differences and predictors of psychological symptoms, quality of life (QoL), and self-esteem were also examined. Thirty-eight school-aged participants with NF1 completed a psychological evaluation designed to assess anxiety and depression symptomatology, QoL, self-esteem, and the prevalence and extent of bullying/cyberbullying and victimization behaviors. We found that our participants frequently reported victimization behaviors rather than bullying/cyberbullying ones. Moreover, participants complained of depressive and anxiety symptomatology together with reduced self-esteem, and low psychosocial quality of life, with females reporting more severe performances than males. Furthermore, we found that reduced self-esteem was associated with more visibility of the NF1 symptoms, and victimization behaviors were found to mediate the relationship between anxiety and psychosocial QoL. Our findings indicated the presence of a maladaptive loop in children and adolescents with NF1 patients characterized by psychological symptoms, unfavorable self-perception, low self-esteem, and psychosocial difficulties that might be worsened by experiencing victimization behaviors. These results suggest the need to use a multidisciplinary approach in the diagnosis and treatment of NF1. [ABSTRACT FROM AUTHOR]

Neurofibromatosis type 1 (NF1) is a genetic multisystemic autosomal dominant disorder determining reduced life expectancy due to higher risk of developing benign and malignant tumors. Low levels of vitamin D and reduced bone mineral density (BMD) have been reported in young patients with NF1. However, correlation between vitamin D and NF1 phenotype needs to be elucidated. Aim of this study was to assess vitamin D levels and bone metabolism in NF1 patients, analyzing potential correlations with clinical phenotype. A cross-sectional study was carried out in a monocentric series of NF1 patients, evaluating genotype, clinical phenotype, BMD, biochemical evaluation with focus on serum 25OH-vitamin D, parathyroid hormone (PTH), calcium and phosphate levels. Correlations between clinical manifestations, neurofibromas, and vitamin D status have been studied in comparison with healthy controls. 31 NF1 adult patients were matched for sex, age and body mass index with 31 healthy controls. A significantly difference in vitamin D level emerged in NF1 patients compared to controls. Interestingly low vitamin D levels correlated with a more aggressive phenotype and with a bigger size of neurofibromas. These data underline that vitamin D deficiency/insufficiency may play a role in clinical severity of neurofibromas in patients with NF1, suggesting the need to check bone status and replace vitamin D in these patients. [ABSTRACT FROM AUTHOR]