Neurofibromatosis type 1 in genetic counseling practice: recommendations of the National Society of Genetic Counselors

Altered body as a source of interactional problems in the family of individuals with neurofibromatosis type 1 - A polish study

BACKGROUND

Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder, whose clinical picture is dominated by visible body changes as well as numerous somatic and behavioural abnormalities.

AIM

The aim of the study was to explore the ways in which the individual experiences NF1 in everyday life, with particular emphasis on the impact of the altered body on family interactions, in addition to the personal and social identity of individuals with NF1.

METHODS

A qualitative study was performed using individual in-depth interviews with 93 individuals with NF1 (median age: 36.69; range: 18 to 64; 26% males).

RESULTS

Body changes caused by NF1 determine the specificity of social interactions in the families of the sick. The strength and direction of the impact of body changes on social interactions depends on their type (visibility, invisibility), as well as the meanings given to them. The visibility of disease lesions triggers an attitude of excessive control and stigmatization in the family, especially on the part of the mothers of individuals with NF1, and prompts a tendency to define the individual through the prism of the disease and its bodily manifestations. In turn, the lack of visibility of disease symptoms gives rise to, especially on the part of the fathers of the sick, opposing attitudes of disease denial, normalization of its symptoms and a tendency to question the disease identity of individuals with NF1. The great intensity of interactional problems concerns especially those families in which NF1 was transmitted through inheritance, and family members blame each other for the disease. This leads to repression and denial of the disease, excluding it from the scope of issues discussed in the family, which is an attempt to avoid the attribution of blame for the disease.

CONCLUSIONS

The body changes resulting from NF1 have social consequences that are of critical importance in the lives of the sick. The impact of NF1 on family interactions depends on the ways in which the disease is understood by the sick individual and his or her family members. The obtained patient-driven data constitute a convenient starting point for designing personalized interventions supporting individuals with NF1 and their families.

Seventy years of pheochromocytomas and paragangliomas in Argentina. The FRENAR database

Pheochromocytomas and paragangliomas (PPGL) are neuroendocrine tumors characterized by the excessive production of catecholamines. This study aims to describe the clinical characteristics of PPGL cases in Argentina over recent decades. A multicenter retrospective cross-sectional analysis was carried out using a database comprising both pediatric and adult patients with confirmed PPGL diagnoses based on pathological reports. A cohort of 486 patients with PPGL was recruited. Women represent 58.4% of the patients, with a mean age of 38.3 years old at the time of diagnosis and 15.2% of the patients were under the age of 18. Hypertension, as well as classic signs and symptoms, were present in 80.9% of the patients. The adrenal incidentaloma, as a mode of presentation, increased in the last two decades rising from 3.9% (1953-2000) to 21.8% (2001-2022), p<0.001. Most tumors were located within the adrenal glands, accounting 83.0% of the cases, with bilateral occurrences noted in 20.0%. The median tumor size was 4.8cm. Local recurrence and metastases were observed in 10.9% and 12.2%. Out of 412 patients, 87.0% exhibited urinary excretion elevation of catecholamines and/or their metabolites. Furthermore, 148 patients, representing 30.4% of the study population, displayed a distinct genetic profile indicative of hereditary syndromes. The distribution of hereditary syndromes revealed that MEN2, VHL, and PGL4 constituted the most prevalent syndromes. This population-based study, spanning seven decades, offers valuable insights into the demographic and clinical characteristics of PPGL patients in Argentina.

Neurofibromatosis Type 1: Optimizing Management with a Multidisciplinary Approach

Neurofibromatosis Type I (NF1) is a complex genetic condition that affects multiple organ systems and presents a unique set of challenges for clinicians in its management. NF1 is a tumor predisposition syndrome that primarily affect the peripheral and central nervous systems via the impact of haploinsufficiency upon neural crest lineage cells including Schwann cells, melanocytes, fibroblasts, etc. NF1 can further lead to pathology of the skin, bones, visual system, and cardiovascular system, all of which can drastically reduce a patient's quality of life (QOL). This review provides a comprehensive examination of the many specialties required for the care of patients with Neurofibromatosis Type 1 (NF1). We delve into the pathogenesis and clinical presentation of NF1, highlighting its diverse manifestations and the challenges they pose in management. The review underscores the importance of a multidisciplinary approach to NF1, emphasizing how such an approach can significantly improve patient outcomes and overall QOL. Central to this approach is the role of the NF expert, who guides a multidisciplinary team (MDT) comprising healthcare professionals from many areas of expertise. The MDT collaboratively addresses the multifaceted needs of NF1 patients, ensuring comprehensive and personalized care. This review highlights the need for further investigation to optimize the workflow for NF1 patients in an MDT setting, and to improve implementation and efficacy.

Improving care for rare genetic neurodevelopmental disorders: A systematic review and critical appraisal of clinical practice guidelines using AGREE II

PURPOSE

Rare genetic neurodevelopmental disorders associated with intellectual disability require lifelong multidisciplinary care. Clinical practice guidelines may support healthcare professionals in their daily practice, but guideline development for rare conditions can be challenging. In this systematic review, the characteristics and methodological quality of internationally published recommendations for this population are described to provide an overview of current guidelines and inform future efforts of European Reference Network ITHACA (Intellectual disability, TeleHealth, Autism, and Congenital Anomalies).

METHODS

MEDLINE, Embase, and Orphanet were systematically searched to identify guidelines for conditions classified as "rare genetic intellectual disability" (ORPHA:183757). Methodological quality was assessed using the Appraisal of Guidelines, Research, and Evaluation II tool.

RESULTS

Seventy internationally published guidelines, addressing the diagnosis and/or management of 28 conditions, were included. The methodological rigor of development was highly variable with limited reporting of literature searches and consensus methods. Stakeholder involvement and editorial independence varied as well. Implementation was rarely addressed.

CONCLUSION

Comprehensive, high-quality guidelines are lacking for many rare genetic neurodevelopmental disorders. Use and transparent reporting of sound development methodologies, active involvement of affected individuals and families, robust conflict of interest procedures, and attention to implementation are vital for enhancing the impact of clinical practice recommendations.

Altered actin dynamics is possibly implicated in the inhibition of mechanical stimulation-induced dermal fibroblast differentiation into myofibroblasts

The formation of hypertrophic scars and keloids is strongly associated with mechanical stimulation, and myofibroblasts are known to play a major role in abnormal scar formation. Wounds in patients with neurofibromatosis type 1 (NF1) become inconspicuous and lack the tendency to form abnormal scars. We hypothesized that there would be a unique response to mechanical stimulation and subsequent scar formation in NF1. To test this hypothesis, we investigated the molecular mechanisms of differentiation into myofibroblasts in NF1-derived fibroblasts and neurofibromin-depleted fibroblasts and examined actin dynamics, which is involved in fibroblast differentiation, with a focus on the pathway linking LIMK2/cofilin to actin dynamics. In normal fibroblasts, expression of α-smooth muscle actin (α-SMA), a marker of myofibroblasts, significantly increased after mechanical stimulation, whereas in NF1-derived and neurofibromin-depleted fibroblasts, α-SMA expression did not change. Phosphorylation of cofilin and subsequent actin polymerization did not increase in NF1-derived and neurofibromin-depleted fibroblasts after mechanical stimulation. Finally, in normal fibroblasts treated with Jasplakinolide, an actin stabilizer, α-SMA expression did not change after mechanical stimulation. Therefore, when neurofibromin was dysfunctional or depleted, subsequent actin polymerization did not occur in response to mechanical stimulation, which may have led to the unchanged expression of α-SMA. We believe this molecular pathway can be a potential therapeutic target for the treatment of abnormal scars.

Perspectives on adapting a mobile application for pain self-management in neurofibromatosis type 1: results of online focus group discussions with individuals living with neurofibromatosis type 1 and pain management experts

OBJECTIVE

Neurofibromatosis type 1 (NF1) is a genetic disorder in which chronic pain commonly occurs. The study sought to understand the needs of individuals with NF1 and pain management experts when adapting a pain self-management mobile health application (app) for individuals with NF1.

DESIGN

We conducted a series of online, audio-recorded focus groups that were then thematically analysed.

SETTING

Online focus groups with adults currently residing in the USA.

PARTICIPANTS

Two types of participants were included: individuals with NF1 (n=32 across six focus groups) and pain management experts (n=10 across three focus groups).

RESULTS

Six themes across two levels were identified. The individual level included lifestyle, reasons for using the mobile app and concerns regarding its use. The app level included desired content, desired features and format considerations. Findings included recommendations to grant free access to the app and include a community support feature for individuals to relate and validate one another's experience with pain from NF1. In addition, participants noted the importance of providing clear instructions on navigating the app, the use of an upbeat, hopeful tone and appropriate visuals.

CONCLUSIONS

Both participant groups endorsed the use of iCanCope (iCC) as an NF1 pain self-management mobile app. Differences between groups were noted, however. The NF1 group appeared interested in detailed and nuanced pain tracking capabilities; the expert group prioritised tracking information such as mood, nutrition and activity to identify potential associations with pain. In tailoring the existing iCC app for individuals with NF1, attention should be paid to creating a community support group feature and to tailoring content, features and format to potential users' specific needs.

[Expert consensus on diagnosis and management of neurofibromatosis type 1 (2021 edition)]

Neurofibromatosis type 1 (NF1) is an autosomal dominant neoplastic disease caused by mutations in the NF1 gene and one of the most challenging diseases to treat. Patients have a characteristic phenotype with neurofibromas as the main features in different forms, including numerous cutaneous neurofibromas, plexiform neurofibromas involving the primary nerves, or malignant peripheral nerve sheath tumors with a very short survival period after malignant transformation. NF1 patients also suffer from multi-system involvement, with a high rate of deformity and disability, making complete surgical resection more difficult. Currently, there is no consensus on the diagnosis and treatment of NF1 in China, and different disciplines have different understandings of NF1. Multidisciplinary systematic evaluations and cooperative treatments are the keys to improve the treatment, quality of life, and prognosis of NF1 patients. In 2020, the Department of Plastic Surgery of the Ninth People's Hospital of Shanghai Jiaotong University School of Medicine led the establishment of the first multi-center collaboration group for NF1 in China. Furthermore, the group had worked with renowned experts from the various departments including surgical oncology, medical oncology, dermatology, reproductive medicine, et al. in China to formulate the "Expert consensus on diagnosis and management of neurofibromatosis type 1 (2021 edition)", aiming to promote standardized and homogeneous treatment covering the whole life cycle of NF1 patients and improve the treatment level and outcome of NF1 patients in China.

Congenital Pigmentary Anomalies in the Newborn

Congenital pigmentary anomalies may be evident at birth or soon after, with some birthmarks becoming apparent later in infancy or early childhood. It is important to recognize various pigmentary anomalies in the neonate, most of which are benign but a subset of which are associated with cutaneous morbidity or systemic ramifications and require further evaluation. This review will focus on pigmentary mosaicism, congenital melanocytic nevi, nevus spilus, dermal melanocytosis, and pigmentary anomalies associated with neurofibromatosis type 1 (café au lait spots, freckling, plexiform neurofibromas, nevus anemicus), tuberous sclerosis (hypomelanotic macules), and incontinentia pigmenti.

Development and Preliminary Evaluation of a Quality-of-Life Questionnaire for Adults with Neurofibromatosis Type 1 (NF1-AdQOL)

BACKGROUND

Neurofibromatosis type 1 (NF1) is a variable and unpredictable multisystem genetic disorder which predisposes to medical complications, cognitive impairment and disfigurement, of all which can impact negatively upon the health related quality of life (HRQOL) of affected adults.

OBJECTIVES

To develop and validate a disease specific HRQOL adult questionnaire to evaluate effects of NF1 from the patient's viewpoint.

METHODS

The NF1 adult HRQOL questionnaire (NF1-AdQOL) was developed based on patient interviews (n=8), survey of clinicians and piloting of the questionnaire. Adults with NF1 (n=114, 18-40 years) were recruited from three Australian genetics clinics and completed the NF1-AdQOL, Skindex-29 and Short Form-36v2 (SF-36v2) questionnaires. An exploratory factor analysis of the NF1-AdQOL was conducted to assess construct validity. Convergent and discriminant validity of the NF1-AdQOL was determined by using the multi-trait multi-method with Skindex-29 and SF-36v2 scores.

RESULTS

Factor analysis indicated that 62.7% of the common variance could be explained by three factors labelled as 'emotions associated with cosmetic appearance' (12 items), 'social functioning and learning' (11 items) and 'physical symptoms' (8 items). NF1-AdQOL had good internal consistency (Cronbach's α = 0.96). Convergent validity was confirmed by moderate associations with similarly named scales of the Skindex-29 and SF-36v2. Results from all HRQOL questionnaires indicated overall healthy HRQOL for young adults with NF1.

CONCLUSIONS

NF1-AdQOL is a relatively valid, feasible and fairly easy to read tool to measure QOL in adults with NF1. Further evaluation is required to determine its test-retest reliability, responsiveness and validity in larger adult NF1 cohorts.

Diagnostic difficulties and possibilities of NF1-like syndromes in childhood

BACKGROUND

Neurofibromatosis type 1 (NF1), which is caused by heterozygous inactivating pathogenic variants in the NF1, has poor phenotypic expressivity in the early years of life and there are numerous conditions, including many other tumor predisposition syndromes, that can mimic its appearance. These are collectively termed NF1-like syndromes and are also connected by their genetic background. Therefore, the NF1's clinical diagnostic efficiency in childhood could be difficult and commonly should be completed with genetic testing.

METHODS

To estimate the number of syndromes/conditions that could mimic NF1, we compiled them through an extensive search of the scientific literature. To test the utility of NF1's National Institutes of Health (NIH) clinical diagnostic criteria, which have been in use for a long time, we analyzed the data of a 40-member pediatric cohort with symptoms of the NF1-like syndromes' overlapping phenotype and performed NF1 genetic test, and established the average age when diagnostic suspicion arises. To facilitate timely identification, we compiled strongly suggestive phenotypic features and anamnestic data.

RESULTS

In our cohort the utility of NF1's clinical diagnostic criteria were very limited (sensitivity: 80%, specificity: 30%). Only 53% of children with clinically diagnosed NF1 had a detectable NF1 pathogenic variation, whereas 40% of patients without fulfilled clinical criteria tested positive. The average age at first genetic counseling was 9 years, and 40% of children were referred after at least one tumor had already been diagnosed. These results highlight the need to improve NF1-like syndromes' diagnostic efficiency in childhood. We collected the most extensive spectrum of NF1-like syndromes to help the physicians in differential diagnosis. We recommend the detailed, non-invasive clinical evaluation of patients before referring them to a clinical geneticist.

CONCLUSIONS

Early diagnosis of NF1-like syndromes can help to prevent severe complications by appropriate monitoring and management. We propose a potential screening, diagnostic and management strategy based on our findings and recent scientific knowledge.

Early-Onset Spinal Deformity in Neurofibromatosis Type 1: Natural History, Treatment, and Imaging Surveillance

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Early-onset scoliosis (EOS) or kyphosis is common in patients with neurofibromatosis (NF) and is characterized by rapid progression of deformity.

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Traditional growing rods provide good functional and deformity outcomes in patients with NF and EOS; magnetically controlled growing rods (MCGRs) also provide good deformity correction, although high rates of revision have been reported after their use.

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Among patients with NF type 1 (NF1), morphologic characteristics of the spinal deformity are different in those with paraspinal neurofibromas than in those without paraspinal tumors.

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Patients with NF1 are at low risk for developing malignant peripheral nerve sheath tumors during childhood (<1%) and their lifetime (8% to 12%), and routine imaging surveillance for malignancy in the absence of symptoms should be clinically directed.

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Further investigation is needed to standardize screening for EOS in children with NF1 and to develop guidelines for ideal imaging modalities, including their frequency and a timeline.

Psychosocial and Socioeconomic Factors in Children with Neurofibromatosis Type 1

The aim of this study is to analyze whether children with familial and sporadic neurofibromatosis type 1 (NF1) differ in psychosocial and socioeconomic aspects such as developmental delay as well as in comorbidities. Medical records of 250 children with NF1 at a median age of 10.6 years (range = 2–20 years at time of data collection) were retrospectively reviewed. Specifically, psychosocial and socioeconomic factors from 88 children with a family history for NF1 and 162 sporadic cases were compared. Comparing IQ, familial cases scored significantly lower than sporadic cases (89.8 vs. 96.5; p = 0.015). IQ scores of children with familial and sporadic NF1 differ depending on level of parental education (mean IQ for high education 101.3 [familial] and 102.8 [sporadic] vs. low education 87.5 [familial] and 90.4 [sporadic]; p < 0.001). No significant differences were found regarding the presence of developmental delay, learning disorders, autism spectrum disorder, or attention deficit hyperactivity disease. Children with inherited NF1 had a significantly lower IQ than sporadic cases. Children with familial NF1 more often had parents with a lower level of education, highlighting a possible impact of NF1 through generations. Also, the present study confirmed previous results in literature regarding high frequencies of learning disabilities, autism spectrum disease, and attention deficits in children with NF1.

The mediating effects of quality of life, depression, and generalized anxiety on perceived barriers to employment success for people diagnosed with Neurofibromatosis Type 1

Background

Neurofibromatosis Type 1 (NF1) is a genetic disorder that presents with physical symptoms that can negatively impact numerous areas of one’s life, including occupational and psychological functioning, with decreased quality of life compared to a normative population. The purpose of the current study was to explore differences in the impact of psychological factors (anxiety and depression), quality of life and employment hope on barriers to successful employment between those with NF1 and matched controls.

Methods

A total of 212 individuals were stratified into two groups (NF1 and matched controls) using a cross-sectional design that collected a one-time response.

Results

A mediation analysis in which total barriers to successful employment on the differences between groups with quality of life, anxiety and depression as the mediators, and levels of employment hope as the co-variates were examined. The results confirmed a direct (.001) and indirect (< .001) relationship between barriers to successful employment with NF1 to matched controls, and with quality of life, anxiety, and depression.

Conclusions

The current findings indicate that the barriers to successful employment for individuals with NF1 impact their quality of life, anxiety, and depression more than that of the matched controls. Poorer barriers of employment observed amongst people with a genetic disease can impact mental health and quality of life.

Familial Nervous System Tumor Syndromes

PURPOSE OF REVIEW

Although sporadic primary neoplasms account for the majority of nervous system tumors, familial nervous system tumor syndromes are important and clinically relevant conditions for the neurologist to understand. This article reviews common inherited nervous system tumor syndromes including neurofibromatosis type 1, neurofibromatosis type 2, schwannomatosis, tuberous sclerosis complex, and von Hippel-Lindau syndrome. The epidemiology, genetics, approach to diagnosis, neurologic and nonneurologic manifestations, and management options are reviewed.

RECENT FINDINGS

Awareness of the more common and clinically relevant familial nervous system tumor syndromes is important. These conditions teach us about the underlying biology that drives tumor development in the central and peripheral nervous systems including peripheral nerve sheath tumors (eg, neurofibroma, schwannoma), meningioma, vestibular schwannoma, subependymal giant cell astrocytoma, and hemangioblastoma. Knowledge of the clinical manifestations ensures that the neurologist will be able to diagnose these conditions, recommend appropriate surveillance, refer to specialists, and support optimal management. Important discoveries in the role of the underlying genetics have contributed to the launch of several novel drug trials for these tumors, which are changing therapeutic options for patients.

SUMMARY

Familial nervous system tumor syndromes are uncommon conditions that require specialized surveillance and management strategies. Coordination across a multidisciplinary team that includes neurologists, neuro-oncologists, radiologists, neurosurgeons, radiation oncologists, otolaryngologists, pathologists, neuropsychologists, physical medicine and rehabilitation specialists, and geneticists is necessary for the optimal treatment of these patients.

Development of a multidisciplinary clinic of neurofibromatosis type 1 and other neurocutaneous disorders in Greece. A 3-year experience

Given the complexity of neurocutaneous syndromes, a multidisciplinary approach has been advocated in order to provide optimum care. Subjects and Methods: Retrospective analysis of a cohort of 157 patients during a 3-year period, seen at a newly developed neurocutaneous clinic in a pediatric tertiary care hospital in Athens (Greece); and systematic chart review of the patients diagnosed with neurofibromatosis type 1 during this time period. Results: The most frequent neurocutaneous syndromes were neurofibromatosis type 1 (NF1) in 89 patients and tuberous sclerosis complex in 17. In 20.38% of patients a neurocutaneous syndrome was not confirmed. Approximately 2/3 of the NF1 patients underwent genetic analysis, and for 76.67% of them, a pathogenic mutation on the NF1 gene was revealed. Eighty-one patients manifested with generalized NF1 and eight with mosaic NF1. Dermatological manifestations included café-au-lait macules in all patients, followed by axillary and/or inguinal freckling (n = 57), external plexiform neurofibromas (n = 17), and cutaneous and subcutaneous neurofibromas (n = 11). Approximately half of patients had learning disabilities and attention deficit hyperactivity disorder, followed by mental retardation (n = 9), autistic spectrum disorders (n = 4), headaches (n = 3) and seizures (n = 2). Neuroimaging showed characteristic areas of hyperintensity on T2-weighted images in 74.07% of patients and optic pathway glioma in 19.75%. Two patients developed malignant peripheral sheath nerve tumor. Conclusions: Neurocutaneous syndromes are clinically heterogeneous and the surveillance of potential clinical complications is challenging. The availability of genetic diagnosis and novel imaging methods in this group of disorders is likely to further expand their clinical spectrum. Guidelines for assessment and management will need to be modified based on new available data.

Bilateral pheochromocytoma after kidney transplantation in neurofibromatosis type 1

We present the case of a 25-year-old male with a history of neurofibromatosis type 1 and bilateral pheochromocytoma 4 years after kidney transplantation that was successfully treated with simultaneous bilateral posterior retroperitoneoscopic adrenalectomy. Learning points: Hypertensive patients with NF1 should always be screened for pheochromocytoma. Pheochromocytoma is rarely associated with transplantation, but it must be ruled out in patients with genetic susceptibility. Posterior retroperitoneoscopic adrenalectomy (PRA) allows more direct access to the adrenal glands, especially in patients with previous abdominal surgeries.

Coordinated medical care for children with neurofibromatosis type 1 and related RASopathies in Poland

Coordinated medical care offered in Poland for patients suffering from neurofibromatosis type 1 and related RASopathies combines complex multispecialty consultation with permanent supervision and the patient's oriented longitudinal care. Neurofibromatosis type 1 is one of the most common single gene disorders in the global population, observed in 1 out of 2500-3000 live births. It is a primary neoplasia disease with 100% penetration of the gene mutation but remarkable age-dependent onset of different disease signs and symptoms, outstanding clinical heterogeneity between patients even in one family and lack of genotype-phenotype correlation, a high rate of spontaneous mutation exceeding 50%, and multiple comorbidities among which increased risk of malignancy is the most important. Medical practice proved that not only patient-oriented complex but also coordinated care provided in centers of competence is indispensable for patients and the families and provides a sense of medical security to them in conjunction with public health costs rationalization.

Clinical Syndromes and Genetic Screening Strategies of Pheochromocytoma and Paraganglioma

Pheochromocytomas (PCCs) are rare neuroendocrine tumors that originate from chromaffin cells of the adrenal medulla, and paragangliomas (PGLs) are extra-adrenal pheochromocytomas. These can be mainly found in clinical syndromes including multiple endocrine neoplasia (MEN), von Hippel–Lindau (VHL) syndrome, neurofibromatosis-1 (NF-1) and familial paraganglioma (FPGL). PCCs and PGLs are thought to have the highest degree of heritability among human tumors, and it has been estimated that 60% of the patients have genetic abnormalities. This review provides an overview of the clinical syndrome and the genetic screening strategies of PCCs and PGLs. Comprehensive screening principles and strategies, along with specific screening based on clinical symptoms, biochemical tests and immunohistochemistry, are discussed.

Rare NF1 microdeletion syndrome in an Omani patient

Neurofibromatosis-1 phenotype combined with webbed neck and short stature in a young Omani patient was revealed to be due to a de novo germ-line heterozygous 1.7 Mb microdeletion at 17q11.2. This lead to the diagnosis of NF1 microdeletion syndrome.

Increased insulin sensitivity in individuals with neurofibromatosis type 1

Objects To compare insulin resistance (IR) and metabolic aspects of patients with neurofibromatosis type 1 (NF1) and individuals without the disease. Subjects and methods Forty patients with NF1 were matched by sex, age, and body mass index (BMI) to 40 controls from the community. Blood samples were collected for biochemical assessment. Homeostasis model assessment adiponectin (HOMA-AD), Homeostasis model assessment insulin resistance (HOMA-IR), and adiponectin/leptin ratio (ALR) were used to identify IR. Results The median HOMA-IR values were similar between the groups. However, the HOMA-AD value was significantly lower and the ALR significantly higher in the NF1 group. Fasting blood glucose (FBG), leptin, and visfatin levels of patients with NF1 were significantly lower, although adiponectin levels were significantly higher than those in the controls. Fasting insulin and blood glucose levels 2 hours after administration of 75 g of dextrose, glycated hemoglobin, and resistin showed no significant differences between groups. The HOMA-AD correlated with BMI, FBG, blood glucose levels 2 hours after administration of 75 g of dextrose, fasting insulin, glycated hemoglobin, adiponectin, leptin, visfatin, ALR, and HOMA-IR. The ALR correlated with BMI leptin, visfatin, and adiponectin. Conclusions Lower levels of FBG, leptin, visfatin, and HOMA-AD, and higher adiponectin levels and ALR may be related to increased insulin sensitivity and lower occurrence of type 2 diabetes mellitus in patients with NF1.

Cancer and Central Nervous System Tumor Surveillance in Pediatric Neurofibromatosis 1

Although the neurofibromatoses consist of at least three autosomal dominantly inherited disorders, neurofibromatosis 1 (NF1), neurofibromatosis 2 (NF2), and schwannomatosis, NF1 represents a multisystem pleiotropic condition very different from the other two. NF1 is a genetic syndrome first manifesting in childhood; affecting multiple organs, childhood development, and neurocognitive status; and presenting the clinician with often complex management decisions that require a multidisciplinary approach. Molecular genetic testing (see article for detailed discussion) is recommended to confirm NF1, particularly in children fulfilling only pigmentary features of the diagnostic criteria. Although cancer risk is not the major issue facing an individual with NF1 during childhood, the condition causes significantly increased malignancy risks compared with the general population. Specifically, NF1 is associated with highly elevated risks of juvenile myelomonocytic leukemia, rhabdomyosarcoma, and malignant peripheral nerve sheath tumor as well as substantial risks of noninvasive pilocytic astrocytoma, particularly optic pathway glioma (OPG), which represent a major management issue. Until 8 years of age, clinical assessment for OPG is advised every 6 to 12 months, but routine MRI assessment is not currently advised in asymptomatic individuals with NF1 and no signs of clinical visual pathway disturbance. Routine surveillance for other malignancies is not recommended, but clinicians and parents should be aware of the small risks (<1%) of certain specific individual malignancies (e.g., rhabdomyosarcoma). Tumors do contribute to both morbidity and mortality, especially later in life. A single whole-body MRI should be considered at transition to adulthood to assist in determining approaches to long-term follow-up. Clin Cancer Res; 23(12); e46-e53. ©2017 AACRSee all articles in the online-only CCR Pediatric Oncology Series.

Identifying Symptoms of Distress in Youth Living with Neurofibromatosis Type 1 (NF1)

Children and adolescents with Neurofibromatosis type 1 (NF1) are at increased risk for wide-ranging behavioral, developmental, and cognitive impairments and decreased quality of life. To date, no psychosocial screening tool has been developed to quickly assess the symptoms that 1) can be addressed during routine medical appointments in children with NF1, 2) can produce interpretable and actionable results, 3) can be integrated into medical care, and 4) can quickly identify patients at risk in order to better address that the provision of appropriate care are available. This study was conducted to test the overall usability of the Distress Thermometer (DT) and symptom checklist and concordance of DT ratings between pediatric patients, their caregivers and medical providers. Eighty youth (ages 7-21) living with NF1 completed the DT and an accompanying checklist. The findings of this study suggest the DT and symptom checklist was acceptable and feasible to complete in a clinic setting. A small subset reported high distress that required further assessment and intervention. Significant discordance between distress ratings of caregivers and children and healthcare providers was also found. Overall, the DT and accompanying symptom checklist provide important information to identify the presence of distress and contextualize the child's distress but is limited by not assessing whether these symptoms interfere with the child's daily life.

Predicting neurofibromatosis type 1 risk among children with isolated café-au-lait macules

BACKGROUND

Although isolated cafe-au-lait macules (CALMs) are a common skin finding, they are an early feature of neurofibromatosis type 1 (NF1).

OBJECTIVE

We sought to develop an algorithm determining the risk of children with CALMs to have constitutional NF1.

METHODS

We conducted a retrospective study of patients with isolated CALMs. Diagnosis of NF1 was based on detecting NF1 mutation in blood or fulfilling clinical criteria.

RESULTS

In all, 170 of 419 (41%) and 21 of 86 (24%) children with isolated CALMs who underwent molecular testing and clinical follow-up, respectively, were given a diagnosis of NF1. Presence of fewer than 6 CALMs at presentation or atypical CALMs was associated with not having NF1 (P < .001). An algorithm based on age, CALMs number, and presence of atypical macules predicted NF1 in both cohorts. According to the algorithm, children older than 29 months with at least 1 atypical CALM or less than 6 CALMs have a 0.9% (95% confidence interval 0%-2.6%) risk for constitutional NF1 whereas children younger than 29 months with 6 or more CALMs have a high risk (80.4%, 95% confidence interval 74.6%-86.2%).

LIMITATIONS

The study was designed to detect constitutional NF1 and not NF1 in mosaic form.

CONCLUSIONS

A simple algorithm enables categorization of children with isolated CALMs as being at low or high risk for having NF1.

Neurofibromatosis Clinic: A Report on Patient Demographics and Evaluation of the Clinic

BACKGROUND

Neurofibromatosis type 1 (NF1) is a common single-gene disorder. A multidisciplinary approach to the management of NF1 patients is necessitated by the heterogeneity of clinical manifestations. Although multidisciplinary paediatric clinics have been well established, there is a dearth of such resources for adults with NF1. Herein we report our one-year institutional experience with a multidisciplinary adult NF1 clinic.

METHODS

A multidisciplinary team was assembled, and an NF Patient Registry Initiative questionnaire was adapted to collect patient-reported data during clinics. Multiple databases were searched to identify publications pertaining to the experience of other multidisciplinary NF1 clinics focusing on adult patients. Data on patient epidemiology and clinical staff were compared to our data.

RESULTS

A total of 77 patients were scheduled, and 68 attended the clinic, of whom 66 completed the intake questionnaire. The demographic and clinical data from this Canadian population are mostly consistent with previous reports, with some exceptions. Clinical data related to immune system involvement such as asthma, airway/breathing-related difficulties or allergies were striking in our NF1 population. Six relevant published reports of other NF1 clinics were identified. Reports from these studies pertained to periods ranging from 10 to 38 months, and the number of adults assessed ranged from 19 to 177 patients.

CONCLUSIONS

The structure of our clinic and the patient volume are comparable to those of other established centres found in the literature. Our data offer valuable cross-sectional prevalence statistics in the Canadian population. The patient-reported data concerning involvement of the immune system contribute to an emerging recognized medical concern within the NF1 population and warrant further clinical and basic investigation.

An Update on Neurofibromatosis Type 1: Not Just Café-au-Lait Spots and Freckling. Part II. Other Skin Manifestations Characteristic of NF1. NF1 and Cancer

Neurofibromatosis type 1 (NF1) is the most common neurocutaneous syndrome and probably the one best known to dermatologists. Although the genetic locus of NF1 was identified on chromosome 17 in 1987, diagnosis of the disease is still based primarily on clinical observations. The 7 diagnostic criteria of the National Institutes of Health, which were established in 1988, include 3 skin manifestations (café-au-lait spots, freckling on flexural areas, and cutaneous neurofibromas). The age at which these diagnostic lesions appear is variable: onset can be late in some patients while others never develop certain symptoms. Definitive diagnosis may therefore be delayed by years. Although the appearance of the characteristic café-au-lait spots and freckling in the early years of childhood are very suggestive of the disease, these signs are not pathognomonic and, in isolation, do not constitute sufficient evidence to establish a definitive diagnosis. Thus, other diagnoses should be considered in patients whose only symptoms are café-au-lait spots and freckling. By contrast, the presence of multiple cutaneous neurofibromas or at least 1 plexiform neurofibroma is a very specific indication of NF1. Identification of the different types of neurofibroma allows us to confirm the diagnosis and initiate appropriate management.

A randomized placebo-controlled lovastatin trial for neurobehavioral function in neurofibromatosis I

Objective

Lovastatin has been shown to reverse learning deficits in a mouse model of Neurofibromatosis Type 1 (NF1), a common monogenic disorder caused by a mutation in the Ras‐MAPK pathway and associated with learning disabilities. We conducted a randomized double‐blind placebo‐controlled trial to assess lovastatin's effects on cognition and behavior in patients with NF1.

Method

Forty‐four NF1 patients (mean age 25.7+/−11.6 years; 64% female) were randomly assigned to 14 weeks of lovastatin (N = 23; maximum dose of 80 mg/day for adult participants and 40 mg/day for children) or placebo (N = 21). Based on findings in the mouse model, primary outcome measures were nonverbal learning and working memory. Secondary outcome measures included verbal memory, attention, and self/parent‐reported behavioral problems, as well as tolerability of medication. Participants also underwent neuroimaging assessments at baseline and 14 weeks, to determine whether neural biomarkers were associated with treatment response. Linear mixed models assessed for differential treatment effects on outcome measures.

Results

Twelve participants dropped from the study prior to completion (8 placebo, 4 lovastatin), resulting in 32 completers (15 placebo, 17 lovastatin). Lovastatin was well‐tolerated, with no serious adverse events. Differential improvement favoring lovastatin treatment was observed for one primary (working memory; effect size f² = 0.70, P < 0.01) and two secondary outcome measures (verbal memory, f² = 0.19, P = 0.02, and adult self‐reported internalizing problems, f² = 0.26, P = 0.03). Exploratory moderator analyses revealed that higher baseline neural activity in frontal regions was associated with larger treatment effects.

Interpretation

These preliminary results suggest beneficial effects of lovastatin on some learning and memory functions, as well as internalizing symptoms in patients with NF1.

Lower fasting blood glucose in neurofibromatosis type 1

Studies indicate a lower occurrence of diabetes mellitus (DM) in patients with neurofibromatosis type 1 (NF1). Fasting blood glucose (FBG) level is the main criterion used to diagnose DM and glucose intolerance. Therefore, this study compared FBG level between adults with NF1 and non-NF1 controls. We selected clinical records of 57 out of 701 individuals attending the Neurofibromatosis Outpatient Reference Center of the Clinics Hospital of the Federal University of Minas Gerais in Brazil. The selected patients with NF1 were matched to non-NF1 controls selected from the Brazilian Longitudinal Study of Adult Health according to sex, age (range, 35-74 years) and BMI at a ratio of 1:3. In both groups, individuals with DM were excluded. Median FBG level in the NF1 group (86 mg/dl (range, 56-127 mg/dl)) was lower than that in the non-NF1 control group (102 mg/dl (range, 85-146 mg/dl)) (P<0.001). Prevalence of FBG level ≥100 mg/dl in the NF1 group (16%) was lower than that in the non-NF1 control group (63%) (P<0.05). The chance of a high FBG level was 89% lower in the NF1 group (odds ratio, 0.112; 95% CI, 0.067-0.188) (P<0.05). In conclusion, adults with NF1 showed a lower FBG level and a lower prevalence of high FBG level compared with non-NF1 controls.

Depression among adults with neurofibromatosis type 1: prevalence and impact on quality of life

Neurofibromatosis type 1 (NF1) carries a significant psychosocial burden for affected individuals. The objective of this study was to measure the prevalence of depressive symptoms among a large sample of adults with NF1 and to quantify the impact of depressive symptoms on quality of life (QoL). This cross-sectional study used an Internet-based questionnaire to collect data from 498 adults who self-reported as having NF1. Using the Center for Epidemiologic Studies Depression (CESD) scale, 55% of all participants (61% of females and 43% of males) scored above 16, indicating a high likelihood of clinical depression. In a multivariate regression model controlling for demographics and potential confounders, depressive symptoms accounted for 32% of the variance in QoL as measured by the Quality of Life Index. This study is the largest to date and found the highest prevalence of depression compared to prior studies. Our data provide more compelling evidence that individuals with NF1 are at increased risk for psychiatric morbidity and suggest that this population should be routinely screened for depression. Because depression was found to be strongly associated with QoL and accounted for nearly one-third of the variance in QoL, it is likely that effectively treating depression may significantly enhance QoL for individuals with NF1.

LEOPARD syndrome: clinical dilemmas in differential diagnosis of RASopathies

Background

Diagnosis within RASopathies still represents a challenge. Nevertheless, many efforts have been made by clinicians to identify specific clinical features which might help in differentiating one disorder from another. Here, we describe a child initially diagnosed with Neurofibromatosis-Noonan syndrome. The follow-up of the proband, the clinical evaluation of his father together with a gene-by-gene testing approach led us to the proper diagnosis.

Case presentation

We report a 8-year-old male with multiple café-au-lait macules, several lentigines and dysmorphic features that suggest Noonan syndrome initially diagnosed with Neurofibromatosis-Noonan syndrome. However, after a few years of clinical and ophthalmological follow-up, the absence of typical features of Neurofibromatosis type 1 and the lack of NF1 mutation led us to reconsider the original diagnosis. A new examination of the patient and his similarly affected father, who was initially referred as healthy, led us to suspect LEOPARD syndrome, The diagnosis was then confirmed by the occurrence in both patients of a heterozygous mutation c.1403 C > T, p.(Thr468Met), of PTPN11. Subsequently, the proband was also found to have type-1 Arnold-Chiari malformation in association with syringomyelia.

Conclusion

Our experience suggests that differential clinical diagnosis among RASopathies remains ambiguous and raises doubts on the current diagnostic clinical criteria. In some cases, genetic tests represent the only conclusive proof for a correct diagnosis and, consequently, for establishing individual prognosis and providing adequate follow-up. Thus, molecular testing represents an essential tool in differential diagnosis of RASophaties. This view is further strengthened by the increasing accessibility of new sequencing techniques.

Finally, to our knowledge, the described case represents the third report of the occurrence of Arnold Chiari malformation and the second description of syringomyelia with LEOPARD syndrome.

Genetic testing by cancer site: skin

Many hereditary cancer predisposition syndromes are associated with cutaneous findings, both benign and malignant. Dermatological examination and histopathology, when combined with a thorough personal and family medical history, play an important role in the diagnosis of cancer predisposition syndromes. Skin findings are an important diagnostic tool for a variety of cancer syndromes, including Cowden syndrome, Birt-Hogg-Dubé, hereditary leiomyomatosis renal cell carcinoma, and others. This article focuses on the phenotype, medical management, and genetic testing for 4 hereditary cancer syndromes that include cutaneous findings: hereditary melanoma, basal cell nevus syndrome, neurofibromatosis type 1, and neurofibromatosis type 2.

Uncertainty management and communication preferences related to genetic relativism among families affected by down syndrome, Marfan syndrome, and neurofibromatosis

Genes hold opportunities for us to look backward and forward in family health and disease incidence. Our beliefs about genes' roles in health form around frameworks relating to personal control, and the influence of social networks and/or religious faith on genetic expression in health. These genetic relativistic frameworks were found to predict levels of illness uncertainty among 541 diagnosed adults and family members affected by neurofibromatosis, Down syndrome, and Marfan syndrome. Participants were recruited and surveyed about their expectations and preferences for communicating about their respective disorder, with illness uncertainty found to predict the desire to communicate about the condition and to manage related uncertainty. The desire to manage uncertainty in ways that foster control and hope partially mediated the relationship between illness uncertainty and communication preferences. Negative feelings about the condition, which were stronger for affected participants than for family members, related to illness uncertainty, the desire to manage uncertainty, and communication preferences, mediating the relationship between illness uncertainty and uncertainty management. Findings contribute to research in illness uncertainty management and have pragmatic implications for the design of counseling and educational materials associated with the genetic conditions considered in this research.

Neurofibromatosis without Neurofibromas: Confirmation of a Genotype-Phenotype Correlation and Implications for Genetic Testing

Neurofibromatosis type 1 (NF1) is a multisystem disease with autosomal dominant inheritance and complete penetrance diagnosed by clinical findings. Cutaneous neurofibromas are present in almost all adult patients in the dermis, epidermis or along the peripheral nerves. Plexiform neurofibromas are subcutaneous or deep lesions involving nerve plexuses or roots. Neurofibromas can degenerate into malignant tumors, with important prognostic implications. NF1 shows a broad clinic variability even within a single family. Exceptions are cases reporting the in-frame microdeletion c.2970_2972delAAT, presenting with the typical pigmentary features of NF1, but no cutaneous or plexiform neurofibromas. We report a patient with a de novo c.2970_2972delAAT mutation who had few café-au-lait spots, only 2 of which measured >15 mm, axillary and submammary freckling, a flat angioma extending over the neck, arm and trunk, a high arched palate, micrognathia, macrocephaly, pes cavus and scoliosis. There was complete absence of observable cutaneous neurofibromas as well as external plexiform neurofibromas. She had had epileptic seizures since childhood; however, a diagnosis of NF1 had not been confirmed until she was 38, partly due to the paucity of characteristic cutaneous stigmata. We confirm the association of the c.2970_2972delAAT mutation in NF1 with a particular clinical phenotype, especially with lack of detectable neurofibromas. For an appropriate management of patients and family counseling, molecular study of the NF1 gene should be considered in patients not fulfilling NIH criteria when other features suggestive of NF1 are present. In the absence of neurofibromas, starting NF1 testing with the screening of exon 17 may be worthwhile.

Comparison of the background, needs, and expectations for genetic counseling of adults with experience with Down syndrome, Marfan syndrome, and neurofibromatosis

We describe an analysis of the responses of 605 adults with experience with Down syndrome, Marfan syndrome, or neurofibromatosis (NF) to the BNE Scale, a scale specifically designed to assess the background, needs, and expectations (BNE) of genetic counseling patients. Significant group differences were found. Specifically, the respondents in the Down syndrome group reported more favorable beliefs about the condition and the availability of social support than the respondents in the other groups. Respondents in the NF group reported more unsureness about their condition and a greater need for genetic information than members of the other groups. Notably, having positive feelings about the condition was negatively correlated with support group interest for respondents of the Marfan syndrome group (r = -0.159, P < 0.01). Having an affected child was associated with interest in health provider input (t = -3.4; P = 0.001) and the desire to talk about psychosocial issues (t = -2.9; P = 0.004). However, previous experience with genetic counseling was not found to affect BNE. These results support the usefulness of the BNE Scale to compare the BNE of patient groups, as well as provide important insight into the BNE of individuals seeking counseling about Down syndrome, Marfan syndrome, and NF.

Neurofibromatosis type 1 and the "elephant man's" disease: the confusion persists: an ethnographic study

BACKGROUND

In 1986, two Canadian geneticists had demonstrated that Joseph Merrick, better known as the Elephant Man, suffered from the Proteus syndrome and not from neurofibromatosis type 1 (NF1), as was alleged by dermatologist Parkes in 1909. Despite this and although the two diseases differ at several levels: prevalence, diagnostic criteria, clinical manifestations and transmission, the confusion between NF1 and the "elephant man's" disease continues in medical and social representations by current linguistic usage, and in some media reports. With this article, we want to 1) document the persistence and extent of this fallacy, 2) identify certain critical factors that contribute to its persistence, and 3) evaluate its impact on the health and well being of patients with NF1 and their family members.

METHODOLOGY

Participant observation in the course of an ethnographic study on intergenerational dialogue between individuals with neurofibromatosis and their parents - Analysis of the scientific literature and of pinpoint articles in the print and online news media.

FINDINGS

Our findings show that because physicians have little knowledge about NF1, several print and online news media and a lot of physicians continue to make the confusion between NF1 and the disease the "elephant man". This misconception contributes to misinformation about the disease, feeding prejudices against affected patients, exacerbating the negative impacts of the disease on their quality of life, their cognitive development, their reproductive choices, as well as depriving them of proper care and appropriate genetic counseling.

CONCLUSION

If family physicians and pediatricians were properly informed about the disease, they could refer their patients with NF1 to NF clinics and to specialists. Thus, patients and their family members would benefit from better-tailored clinical management of their cases, perhaps even optimal management. [corrected]

Inherited cancer syndromes in children and young adults

Geneticists estimate that 5% to 10% of all cancers diagnosed in the pediatric age range occur in children born with a genetic mutation that directly increases their lifetime risk for neoplasia. However, despite the fact that only a fraction of cancers in children occur as a result of an identified inherited predisposition, characterizing genetic mutations responsible for increased cancer risk in such syndromes has resulted in a profound understanding of relevant molecular pathways involved in carcinogenesis and/or resistance to neoplasia. Importantly, because most cancer predisposition syndromes result in an increased risk of a small number of defined malignancies, personalized prophylactic surveillance and preventive measures can be implemented in affected patients. Lastly, many of the same genetic targets identified from cancer-prone families are mechanistically involved in the majority of sporadic cancers in adults and children, thereby underscoring the clinical relevance of knowledge gained from these defined syndromes and introducing novel therapeutic opportunities to the broader oncologic community. This review highlights the clinical and genetic features of many of the known constitutional genetic syndromes that predispose to malignancy in children and young adults.

Genetics and Cognition

How genes contribute to cognition is a perennial question for psychologists and geneticists. In the early 21st century, familial studies, including twin studies, supported the theory that genetic variations contribute to differences in cognition, but have been of little practical use to clinical and educational practitioners as no individual predictions can be made using such data; heritability cannot predict the impact of environmental factors or intervention programs. With the sequencing of animal genomes and the development of molecular genetics, new methodologies have been developed: gene targeting (replacing a functional gene with a neutral gene by homologous recombination), transgenesis (overexpressing one gene or a set of genes from one species in another species), and genome-wide scans and quantitative trait loci mapping (a strategy for identifying chromosomal regions involved in complex traits). Association studies can be performed to find associations between allelic forms and variations in IQ. Genes linked to “normal” variations in cognition have been detected but for the moment such discoveries have had no direct applications in a clinical setting; the number of genes identified as being linked to intellectual impairment has increased rapidly. Links have been reported between chromosomal deletions and triplications and behavioral phenotypes. The identification of mechanisms involved in genetic diseases should have long-term consequences on educational and/or psychological support programs as well as on health care. Psychologists need to keep up to date on advances in research establishing relationships between genetics and intellectual disability and will thus be able to refer children with cognitive impairments to specialized care services.

Detection and characterization of NF1 microdeletions by custom high resolution array CGH

In 5% to 10% of cases, neurofibromatosis type 1 is caused by microdeletions scattered across the entire NF1 gene and various neighboring genes. The phenotype appears to be more severe in patients with NF1 microdeletions than in patients with NF1 single point mutations. We have developed a new method for detecting and characterizing NF1 microdeletions based on a custom high-resolution oligonucleotide array comparative genomic hybridization by using the custom 8x15K Agilent array format. The array comprised a total of 14,207 oligonucleotide probes spanning the whole of chromosome 17, including 12,314 probes spanning an approximately 8 Mb interval surrounding the NF1 locus. We validated this approach by testing NF1 microdeleted DNA samples previously characterized by means of microsatellites and real-time PCR methods. Our array comparative genomic hybridization provided enough information for subsequent long-range PCR and nucleotide sequencing of the microdeletion endpoints. Unlike previously described methods, our array comparative genomic hybridization was able to unambiguously differentiate between the three types of microdeletions (type I, type II, and atypical) and to characterize atypical microdeletions. Further comparative studies of patients with well-characterized genotypes and phenotypes and different microdeletions sizes and breakpoints will help determine whether haploinsufficiency of deleted genes and/or genes rearrangements influence clinical outcomes.

Genetics of chromaffin tumors

The old term of 'chromaffin tumors' encompasses both pheochromocytomas (PHs) and paragangliomas (PGLs). The identification of SDHx genes - new mitochondrial tumor-suppressor genes involved in hypoxia/angiogenesis pathways causing hereditary PGL/PH syndromes - has dramatically changed the genetics of chromaffin tumors. Between 25 and 30% of PGLs/PHs are inherited and are caused by a germline mutation in one of the six susceptibility genes (NF1, RET, VHL, SDHD, SDHB and SDHC). All patients with PGLs/PHs should, therefore, attend genetic counsultations. Genetic testing can be targeted according to family and clinical history. The identification of an inherited disease modifies the management and follow-up of index case and provides an opportunity for predictive genetic testing for other family members.