[Neurofibromatosis 1: recommendations for management]

[Clinical aspects of Neurofibromatosis type 1 seen in the Department of Dermatology at University Hospital Antananarivo, Madagascar]

INTRODUCTION

Neurofibromatosis 1 (NF1) is an inherited disease, in an autosomal dominant manner, with complex multi-system involvements. Prevalence varies from one country to another. However, little is known about neurofibromatosis in African countries, particularly in Madagascar.

METHODOLOGY

A descriptive retrospective study from 2014 to 2019 was conducted at the service of dermatology at University Hospital Joseph Raseta Befelatanana in Antananarivo, including all patients with neurofibromatosis according to National Institutes of Health Consensus Conference criteria for whom genealogical investigation could be made.

RESULTS

Among 32 cases of NF1 seen during 6 years, 28 cases were included with a sex ratio M/F of 0.87. The mean age was 24 years ranging from 11 to 54 years. Seventeen patients presented sporadic forms. All patients had "café au lait" spots and cutaneous neurofibromatosis. Three cases presented plexiform neurofibromas which cause significant cosmetic and functional problems by their size and their displayed topography. Fifteen patients had Lisch nodules but no case of optic glioma was identified. Neurological symptoms such as learning difficulties, epilepsy and headache were frequent in our case series. However, access to medical imaging was very limited. Scoliosis was the most common orthopedic complication.

CONCLUSION

The clinical manifestations of NF1 are extremely variable. Although the possibility of systemic complications seems to be low, patients must be followed up.

[Management of cervico-cephalic plexiform neurofibromas: About 35 cases]

OBJECT

Plexiform neurofibroma is a characteristic lesion of Von Recklinghausen's disease. Conservative surgery is the most widely adopted treatment. However, it is very challenging because of its hemorrhagic nature and the infiltrative aspect of the lesions. The aim of this study was to evaluate our management.

PATIENTS AND METHOD

A retrospective study over 16 years was realized and during this period 35 patients with neurofibroma with cervico-facial location were included.

RESULTS

There were 18 men and 17 women with an average age of 23 years (3-50 years). The familial form was found in 9% of patients. Aesthetic discomfort was noted in all patients and functional impairment only occurred in 10% of patients. The NFP was localized at the hemiface in 11 cases, periorbital in 6 cases, naso-labial in 5 cases, scalp in 4 cases, jugal in 4 cases and cervico-chin in 5 cases. Size of the lesions averaged 11.6cm (4-45cm). Eighteen patients (51.4%) were operated including 10 by modeling resection, 05 cervico-facial lifting and 3 complete resections. Complication rate was 28% dominated by disunion wound. The average number of procedures was 1.6 (1 to 5). After 3 years average follow-up, aesthetic et functional results was assessed as good over 75 per cent of patients.

CONCLUSION

Cervico-facial plexiform neurofibromas is challenging. Conservative surgery should be the gold standard and long time follow-up is recommended.

Neurofibromatosis 1 French national guidelines based on an extensive literature review since 1966

Neurofibromatosis type 1 is a relatively common genetic disease, with a prevalence ranging between 1/3000 and 1/6000 people worldwide. The disease affects multiple systems with cutaneous, neurologic, and orthopedic as major manifestations which lead to significant morbidity or mortality. Indeed, NF1 patients are at an increased risk of malignancy and have a life expectancy about 10-15 years shorter than the general population. The mainstay of management of NF1 is a patient-centered longitudinal care with age-specific monitoring of clinical manifestations, aiming at the early recognition and symptomatic treatment of complications as they occur. Protocole national de diagnostic et de soins (PNDS) are mandatory French clinical practice guidelines for rare diseases required by the French national plan for rare diseases. Their purpose is to provide health care professionals with guidance regarding the optimal diagnostic and therapeutic management of patients affected with a rare disease; and thus, harmonizing their management nationwide. PNDS are usually developed through a critical literature review and a multidisciplinary expert consensus. The purpose of this article is to present the French guidelines on NF1, making them even more available to the international medical community. We further dwelled on the emerging new evidence that might have therapeutic potential or a strong impact on NF1 management in the coming feature. Given the complexity of the disease, the management of children and adults with NF1 entails the full complement healthcare providers and communication among the various specialties.

Intrapericardial neurofibromatosis with coronary involvement: A case report

Neurocutaneous syndromes are heterogenous diseases that are diagnosed in the presence of skin and central nervous system disorders. Neurofibromatosis (NF) is one of these disorders, with autosomal dominant inheritance, that causes tumors that grow on nerves as well as other abnormalities such as skin changes and bone deformities. The most common form of NF is type I. A 6-year-old Iranian boy with neurofibromatosis was referred to the pediatric cardiology clinic due to a soft holosystolic murmur discovered on routine examination. The echocardiographic findings included a large intrapericardial, encapsulated echodense homogenous mass located in the posterior part of the pericardium, attached to the posterior aspect of the left atrium and left ventricle. The mass measured about 6.3×6.5×5.5cm and exerted a compressive effect on the left-side chambers, with mild mitral regurgitation and mild pericardial effusion. Magnetic resonance imaging confirmed these findings showing encasement of the left circumflex artery, while the open biopsy through a midsternotomy procedure showed a mildly cellular mesenchymal tumor composed of spindle cells suggestive of neurofibroma. Further resection of the mass was not performed because of the risk of coronary injury and the stable situation of the patient. Visceral involvement of neurofibroma is uncommon and rarely involves the heart. As shown in this case, besides the chance for involving the pericardium, despite its benign nature, this tumor sometimes shows unusual involvement of structures such as the coronary arteries.

A case report of cervical neurofibrosarcoma: Clinical presentation, treatment and outcome

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Malignant peripheral nerve sheath tumors are highly aggressive soft tissue sarcomas with poor prognosis.

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The recurrence rate is high.

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Complete surgical resection is the mainstay of therapy, when possible.

Introduction

Malignant peripheral nerve sheath tumors (MPNST) are highly aggressive soft tissue sarcomas in which complete surgical resection is the mainstay of therapy.

Clinical presentation

We report a case of MPNST, a 24 year old patient with right neck painful mass of 13 cm of greater dimension, skin spots, lentigos, cutaneous neurofibromas. The neck CT scan revealed a mass with liquid and soft tissues densities. Surgery was performed through right cervical Paul André incision and allowed exeresis of a hemorrhagic mass expensing on the cranial nerves X, XI, XII and the cervical sympathetic chain. Pathology analysis revealed a neurofibrosarcoma, the patient received six doses of chemotherapy. A second surgery was performed one year later after the appearance of a rapidly growing neck mass on the same site. The patient deceased in the intensive care unit one day post-op.

Discussion

Neurofibrosarcoma is a rare clinical entity most often reported as case report. This tumor takes its origin from nerve structures such as the brachial plexus, the cervical sympathetic chain and the cranial nerves and their branches. The appearance of pain, size modification or signs of nerve root compression should warn us to search for a malignant degeneration. Surgery is the base of treatment, associated to radiotherapy and chemotherapy. Vinblastin and doxorubicin were used by other authors in association to radiotherapy with complete local control of inoperable tumors. The 5-year survival is 50% in patients with a neurofibrosarcoma de novo.

Conclusion

The prognosis of neurofibrosarcoma is poor, prompting aggressive local (surgery) and systemic treatment (radiotherapy and/or chemotherapy).

Systematic MRI in NF1 children under six years of age for the diagnosis of optic pathway gliomas. Study and outcome of a French cohort

BACKGROUND/PURPOSE

Optic pathway glioma (OPG) is the most common central nervous system tumor in children with neurofibromatosis type 1 (NF1), affecting 15-20% of patients. We reviewed the medical records of children systematically screened by ophthalmologic and MRI examinations to determine the influence of screening on the therapeutic management of children with OPG.

METHODS

Data were collected on 306 newly diagnosed cases screened with systematic MRI from January 2001 to July 2007. In the OPG group, we distinguished the asymptomatic or symptomatic groups according to their initial status.

RESULTS

Forty-five patients had confirmed OPG (14.7%). Thirty-six patients (80%) were asymptomatic and nine (20%) were symptomatic at the time of diagnosis with visual symptoms in six cases. The average age at OPG diagnosis was 3.4 years with six patients (13%) over six years old. Average follow-up was 7.7 years. Progression was observed in 16 cases (35%). Most patient conditions were managed conservatively (87%). Six children (13%) were treated with chemotherapy due to worsening visual function. All of these children had severe or mild visual impairment at the end of follow-up.

CONCLUSION

Our study does not support a clear benefit of systematic MRI screening in NF1 children under six years old. Systematic neuroimaging in our study did not influence therapeutic management. Although OPG diagnosis was made early, treatment with chemotherapy did not improve the final visual outcome. If MRI remains the best tool for the diagnosis of cerebral and spinal pathologies in the NF1 population, our current study questions the usefulness of systematic MRI screening for OPG diagnosis. Conversely, this study suggests that the indication of neuroimaging should be dictated by the results of annual clinical and ophthalmological assessments.

[Management of craniofacial type 1 neurofibromatosis]

Type I neurofibromatosis (NF) is the most common autosomal dominant disease. It concerns one in 3000 births, the penetrance is close to 100% and 50% of new cases are de novo mutations (17q11.2 chromosome 17 location). Cranio-maxillofacial region is concerned in 10% of the cases, in different forms: molluscum neurofibroma, plexiform neurofibroma, cranio-orbital neurofibroma, parotido-jugal neurofibroma, cervical neurofibroma. These lesions have different prognosis depending on the craniofacial localization: ocular functional risk, upper airway compressive risk, nerve compression risk, aesthetic and social impact. The maxillofacial surgeon in charge of patients with type I NF should follow the patient from the diagnosis and organize the different surgical times in order to take care about the different issues: vital, functional and aesthetic. We describe the treatment of facial localizations of type 1 NF as it is done at the University Hospital of Lyon and at the Rhône-Alpes-Auvergne neurofibromatosis reference center.

[Phenotypic and genetic features in neurofibromatosis type 1 in children]

INTRODUCTION

Neurofibromatosis type 1 (NF1) is the most common neurocutaneous disease, nevertheless the number of publications providing clinical and genetic data from a significant number of children is limited.

MATERIAL AND METHODS

The available clinical, epidemiological, radiological and genetic data from 239 children with NF1, who attended at a specialist NF1 clinic between January 2011 and December 2013 were recorded.

RESULTS

All the 239 patients had a clinical and/or genetic diagnosis of NF1. The mean age at diagnosis was 2.65±2.85 years. In our series 99.6% met the diagnostic criteria of café au lait spots, 93.7% those of axillary and inguinal freckling, 7.1% showed typical bone lesion, 38.1% neurofibromas, 23% plexiform neurofibromas, 31.4% optic pathway glioma, Lisch nodules were present in 43.1%, and 28% patients had a first degree relative affected with NF1. The NF1 genetic study was performed in 86 patients, and a description of the gene mutations found in 72 of them is presented. Furthermore, other clinical data previously associated with NF1, either because of their frequency or their severity, are detailed.

CONCLUSIONS

The difficulty for clinical diagnosis of NF1 early ages is still evident. Although, the need for further studies in asymptomatic patients is discussed, cranial MRI in children with NF1 may be helpful in the clinical diagnosis, given the high frequency of optic glioma observed in this cohort.

Sirolimus improves pain in NF1 patients with severe plexiform neurofibromas

Plexiform neurofibromas (PNs) are common and potentially debilitating complications of neurofibromatosis 1 (NF1). These benign nerve-sheath tumors are associated with significant pain and morbidity because they compress vital structures. The mammalian target of rapamycin (mTOR) pathway is a major mediator involved in tumor growth in NF1. We present 3 cases of patients with NF1, aged 8, 16, and 17 years, followed for inoperable and symptomatic PNs; patients received sirolimus for life-threatening and painful neurofibromas after multidisciplinary consultation. Epidemiologic, clinical, and radiologic data were retrospectively collected. The volume of PNs did not differ between baseline and 12-month follow-up and pain was alleviated, with withdrawal of analgesics in 2 cases at 6 months, and significantly decreased for the third case. Sirolimus for inoperable symptomatic PNs in patients with NF1 permitted stabilization of mass and produced unpredictable and important alleviation of pain in all cases with good tolerance. This treatment was proposed in extreme cases, in absence of therapeutic alternatives, after multidisciplinary consensus. The mTOR pathway may be both a major mediator of NF1 tumor growth and regulator of nociceptor sensitivity. mTOR inhibitors clinically used as anticancer and immunosuppressant drugs could be a potential treatment of chronic pain.

Plexiform neurofibroma of the wrist: imaging features and when to suspect malignancy

Plexiform neurofibromas are essentially pathognomonic for neurofibromatosis type 1 (NF1), occurring when there is diffuse involvement along a nerve segment and its branches. Transformation into a malignant peripheral nerve sheath tumour (MPNST) is a major cause of mortality in NF1 patients. These tumours are highly aggressive and particularly difficult to diagnose in NF1 patients due to the clinical overlap between benign and malignant lesions. We present a case of a plexiform neurofibroma and discuss the typical imaging characteristics on ultrasound, CT, and MRI, including the target sign and continuity with the parent nerve. Certain imaging features should raise suspicion for malignancy however, these modalities may not always reliably differentiate between benign and malignant lesions. Recent studies show a very high negative predictive value for FDG-PET making it quite useful in excluding malignancy. In positive scans, PET/CT aids in guiding biopsy to the most metabolically active area of the tumour.

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]

Assessment of benign tumor burden by whole-body MRI in patients with neurofibromatosis 1

People with neurofibromatosis 1 (NF1) have multiple benign neurofibromas and a 10% lifetime risk of developing malignant peripheral nerve sheath tumors (MPNSTs). Most MPNSTs develop from benign plexiform neurofibromas, so the burden of benign tumors may be a risk factor for developing MPNST. We studied 13 NF1 patients with MPNSTs and 26 age- and sex-matched controls (NF1 patients who did not have MPNSTs) with detailed clinical examinations and whole-body MRI to characterize their body burden of internal benign neurofibromas. Internal plexiform neurofibromas were identified in 22 (56%) of the 39 NF1 patients studied. All six of the NF1 patients with MPNSTs under 30 years of age had neurofibromas visualized on whole-body MRI, compared to only 3 of 11 matched NF1 controls under age 30 (p < 0.05). Both the median number of plexiform neurofibromas (p < 0.05) and the median neurofibroma volume (p < 0.01) on whole-body MRI were significantly greater among MPNST patients younger than 30 years of age than among controls. No significant differences in whole-body MRI findings were observed between NF1 patients with MPNSTs and controls who were 30 years of age or older. Whole-body MRI of NF1 patients allows assessment of the burden of internal neurofibromas, most of which are not apparent on physical examination. Whole-body imaging of young NF1 patients may allow those at highest risk for developing MPNST to be identified early in life. Close surveillance of these high-risk patients may permit earlier diagnosis and more effective treatment of MPNSTs that develop.

A case of neurofibromatosis 1 presenting with optic pathway glioma with an early onset and an aggressive course

Optic pathway glioma associated with neurofibromatosis 1 has a classically indolent course. However, involvement of the optic radiations is relatively rare and is associated with a more aggressive course. A three-year-old girl presented with strabismus and loss of vision in the left eye with relative afferent pupillary defect and optic disc pallor. She had multiple café au lait spots. Visually evoked potential was suggestive of an optic nerve conduction defect and magnetic resonance imaging of the brain was suggestive of an optic pathway glioma involving the optic nerves, the optic chiasma and the optic tracts. The optic radiations and the dentate nuclei had hamartomas. Optic nerve biopsy confirmed pilocytic astrocytoma. Radical radiotherapy under general anesthesia was subsequently given. This case report aims to highlight the involvement of the optic radiations and the unusually aggressive clinical course in this case.

Preventive neurosurgery: population-wide check-up examinations and correction of asymptomatic pathologies of the nervous system

BACKGROUND

Prevention in healthcare is attracting more and more attention. Early identification and correction of anomalies harbouring the risk of a catastrophic event such as aneurysms is the principal rationale for brain check-up programmes. The other aim of preventive screening is to identify progressive lesions with little reversibility such as gliomas. The purpose of the current analysis is to review the frequency of the various incidental findings, the inherent risk and the therapeutic options. RATIONALE FOR CHECK-UP IMAGING AND PREVENTIVE TREATMENT: The average prevalence of asymptomatic intracranial benign tumours, aneurysms and carotid stenoses must be estimated as approximately 1% each. Meningiomas, aneurysms and carotid stenosis become more frequent with increasing age. Mainly vascular anomalies harbour a risk of a catastrophic event, i.e. carotid stenosis and intracranial aneurysms. Only gliomas potentially lose reversibility with time passing. The case of glioma appears to be lost since asymptomatic gliomas are extremely rarely identified on screening examinations, and on the other hand current treatment series do not support that infiltrating gliomas can be cured if only treated early enough. Treatment of the benign tumours, hydrocephalus and arachnoid cysts in the asymptomatic stage does not appear to provide any benefit. RATIONALE FOR GENETIC SCREENING: A number of intracranial tumours, vascular anomalies and degenerative changes are genetically determined. Examples are neurofibromatosis, tuberous sclerosis, von Hippel-Lindau disease and Rendu-Osler's disease. Although familial clustering of aneurysms is well known, the exact genetic anomaly is unknown and probably several genes play a role. Because of the variable penetrance of the inherited disorders with known genetic alterations, screening of affected families is recommended. The conditions are too rare to justify screening of the entire population. Apolipoprotein E genotype is the only accepted predictor of dementia. Routine screening APOE may be considered today, but is highly problematic due to the lack of clear consequences and the potentially negative psychological impact.

COSTS

Implementation of population-wide screening programmes and preventive measures would lead to a substantial additional financial burden. Brain-check-up programmes cannot be considered in isolation. Cardiovascular and oncological programmes would also have to be included from that point of view.

CONCLUSIONS

Population-wide screening with regard to intracranial aneurysms or carotid stenosis with non-invasive imaging techniques and preventive surgery/endovascular therapy can be justified, provided that treatment-associated morbidity is very low. There is no evidence for the rationale of screening for asymptomatic intracranial tumours, cysts or hydrocephalus. Genetic screening cannot be generally recommended, except among families affected by inherited conditions.

Complications de la neurofibromatose de type 1 chez l'enfant : à propos d'une série de 100 cas

Neurofibromatosis 1 (NF1) is a frequent genetic disease. Diagnostic criterias were established in 1988. The patients can exhibit various and unpredictable complications.

OBJECTIVES

To check the efficiency of a coordinated follow-up in specialized multidisciplinary centers providing a higher quality of management and to have a better knowledge of the complications including their true frequencies.

POPULATION AND METHODS

We report a serie of 100 NF1 children who were followed-up during 4 years in a specialized center at the Tours University Hospital. Three hospital check-up at 2-5, 6-7, 14-15 years of age were performed as well as an annual physical examination.

RESULTS

In our serie, the mean age was 7.8 years old with a sex ratio of 1. The mean age at diagnosis was 3.8 years old and the main diagnosis criteria were the café-au-lait spots and the family history for 80% of the patients. The optic nerve glioma has a low frequency of 5%. Learning disabilities clearly represent the most frequent complication (46% of the patients).

CONCLUSION

An early detection of these difficulties is a priority for the appropriate management of these children.

[Imaging features of neurofibromatosis type 1]

Neurofibromatosis type 1 (NF1) is the most common of all the phakomatoses. It is an autosomal dominant disorder, with about 50% of patients being new mutations. NF1 is diagnosed based on the presence of well established diagnostic criteria. Prominent cutaneous manifestations include cafe-au-lait spots, freckling and cutaneous neurofibromas. CNS lesions are frequent and imaging is valuable for diagnosis, treatment and follow-up of patients. Tumors of the central nervous system are frequent. Optic nerve glioma usually affects younger patients with clinical symptoms in one third of cases. MRI shows fusiform enlargement with variable enhancement of the optic nerve. These tumors are usually non-aggressive with good prognosis. Other gliomas and astrocytomas can occur as well, usually midline in location, that also generally have good prognosis. Non-tumoral white matter lesions, referred as unidentified bright objects or UBO's, are frequently observed, typically in the basal ganglia and posterior fossa structures. These lesions are usually seen during childhood and they typically diminish with age. The distinction between UBO's and other tumors may be difficult to achieve at imaging, and a malignant evolution may very rarely be observed. Patients with NF1 may have hydrocephalus and dural sac anomalies leading to meningocele formation. Neurofibromas and plexiform neurofibromas involve peripheral nerves and nerve sheaths. Plexiform neurofibromas may cause radicular symptoms. They more frequently involve the lumbosacral plexus. Neurofibromas are homogeneous oval shaped tumors that may extend into the spinal canal. Neurofibrosarcoma is the main cause of death of NF1 patients less than 40 years of age. It may develop de novo or from sarcomatous degeneration of a pre-existing plexiform neurofibroma. It should be suspected in patients with new onset of symptoms or patients with changing symptoms. At imaging, it is characterized by a large heterogeneous tumor invading adjacent structures. Osseous lesions have been described including progressive thoracic scoliosis, vertebral anomalies (posterior scalloping is very suggestive), long bones anomalies with frequent bowing of the tibia, sometimes resulting in pseudarthrosis, and rib anomalies with ribbon ribs. Vascular lesions may occur resulting in arterial hypertension and aneurysm formation.

Pediatric brain MRI in neurofibromatosis type I

Neurofibromatosis (NF) is the most common of the phakomatoses, with a prevalence of 1 in 3-4,000. Many organ systems can be affected. In addition to multiple peripheral neurofibromas, NF I predisposed to CNS tumors including optic glioma, astrocytoma and plexiform neurofibroma. The purpose of this pictorial review is to illustrate characteristic brain MR imaging lesions in children with NF I and to give some recommendations about diagnostic imaging procedures in children suffering from NF I. Typical findings in brain MRI are hyperintense lesion on T2-weighted images, so-called unknown bright objects, which may be useful as an additional imaging criterion for NF I. Contrast administration is necessary in MR studies to maximize tumor detection and characterization, to add confidence to the diagnosis of benign probable myelin vacuolization, and to document stability of neoplasm on follow-up examinations. We recommend to perform serial MR imaging in children every 12 months. The frequency of follow-up in children with known brain tumors will vary with the tumor grade, biological activity and treatment.