Neurofibromatoses

Scoring model to predict postoperative neurological deterioration in spinal schwannoma

Background

Spinal schwannomas (SSs) are benign tumors affecting the nerve sheath, accounting for 25% of spinal nerve root tumors. Surgery represents the mainstay of treatment for SS patients. Following surgery, approximately 30% of patients experienced developed new or worsening neurological deterioration, which probably represented an inevitable complication of nerve sheath tumor surgery. The objective of this study was to identify the rates of new or worsening neurological deterioration in our center and accurately predict the neurological outcomes of patients with SS by developing a new scoring model.

Methods

A total of 203 patients were retrospectively enrolled at our center. Risk factors associated with postoperative neurological deterioration were identified by multivariate logistic regression analysis. β–coefficients for independent risk factors were used to define a numerical score to generate a scoring model. The validation cohort at our center was used to verify the accuracy and reliability of the scoring model. Receiver operating characteristic (ROC) curve analysis was used to evaluate the performance of the scoring model.

Results

In this study, five measured variables were selected for the scoring model: duration of preoperative symptoms (1 point), radiating pain (2 points), tumor size (2 points), tumor site (1 point), and dumbbell tumor (1 point). The scoring model divided the spinal schwannoma patients into three categories: low risk (0-2 points), intermediate risk (3-5 points), and high risk (6-7 points), with predicted risks of neurological deterioration of 8.7%, 36%, and 87.5%, respectively. And the validation cohort confirmed the model with the predicted risks of 8.6%, 46.4%, and 66.6%, respectively.

Conclusion

The new scoring model might intuitively and individually predict the risk of neurological deterioration and may aid individualized treatment decision-making for SS patients.

Intradural Pediatric Spinal Tumors: An Overview from Imaging to Novel Molecular Findings

Pediatric spinal tumors are rare and account for 10% of all central nervous system tumors in children. Onset usually occurs with chronic nonspecific symptoms and may depend on the intra- or extradural neoplastic location. Meningiomas, schwannomas, and neurofibromas are the most common intradural-extramedullary lesions, while astrocytomas and ependymomas represent the majority of intramedullary tumors. The new molecular discoveries regarding pediatric spinal cancer currently contribute to the diagnostic and therapeutic processes. Moreover, some familial genetic syndromes can be associated with the development of spinal tumors. Currently, magnetic resonance imaging (MRI) is the standard reference for the evaluation of pediatric spinal tumors. Our aim in this review was to describe the imaging of the most frequent intradural intra/extramedullary pediatric spinal tumors and to investigate the latest molecular findings and genetic syndromes.

Primary intratracheal schwannoma misdiagnosed as severe asthma in an adolescent: A case report

BACKGROUND

Primary intratracheal schwannoma is an extremely rare type of benign airway tumor, especially in adolescents. The presenting symptoms are typically prolonged cough and wheezing that can be misdiagnosed as asthma in adolescent patients.

CASE

A 16-year-old adolescent girl admitted to a local hospital with symptoms of an irritating cough and wheezing was diagnosed with bronchial asthma and treated with budesonide and formoterol. Over the next year, the patient's wheezing and coughing symptoms gradually worsened and the antiasthma treatment was ineffective. One week prior to this admission, the patient developed dyspnea after catching a cold and was transferred to our hospital with a diagnosis of severe asthma. However, chest computed tomography and bronchoscopy showed a mass in the trachea. Primary intratracheal schwannoma was diagnosed by biopsy. Her symptoms were relieved by endoscopic resection by electrosurgical snaring combined with argon plasma coagulation. No relapse occurred during an 18 mo follow-up.

CONCLUSION

Primary intratracheal schwannoma should be considered in the differential diagnosis in adolescents with recurrent asthma-like attacks.

Understanding the Biological Activities of Vitamin D in Type 1 Neurofibromatosis: New Insights into Disease Pathogenesis and Therapeutic Design

Vitamin D is a fat-soluble steroid hormone playing a pivotal role in calcium and phosphate homeostasis as well as in bone health. Vitamin D levels are not exclusively dependent on food intake. Indeed, the endogenous production-occurring in the skin and dependent on sun exposure-contributes to the majority amount of vitamin D present in the body. Since vitamin D receptors (VDRs) are ubiquitous and drive the expression of hundreds of genes, the interest in vitamin D has tremendously grown and its role in different diseases has been extensively studied. Several investigations indicated that vitamin D action extends far beyond bone health and calcium metabolism, showing broad effects on a variety of critical illnesses, including cancer, infections, cardiovascular and autoimmune diseases. Epidemiological studies indicated that low circulating vitamin D levels inversely correlate with cutaneous manifestations and bone abnormalities, clinical hallmarks of neurofibromatosis type 1 (NF1). NF1 is an autosomal dominant tumour predisposition syndrome causing significant pain and morbidity, for which limited treatment options are available. In this context, vitamin D or its analogues have been used to treat both skin and bone lesions in NF1 patients, alone or combined with other therapeutic agents. Here we provide an overview of vitamin D, its characteristic nutritional properties relevant for health benefits and its role in NF1 disorder. We focus on preclinical and clinical studies that demonstrated the clinical correlation between vitamin D status and NF1 disease, thus providing important insights into disease pathogenesis and new opportunities for targeted therapy.

Unexpected high frequency of neurofibroma in the celiac ganglion of German cattle

In a study originally designed to find potential risk factors for bovine spongiform encephalopathy (BSE) we examined tissues from 403 Holstein Frisian cattle in total. These included 20 BSE cattle and their 236 birth- and feeding cohort animals plus 32 offspring, 103 age, breed and district-matched control cattle and further twelve cattle with neurological signs. In addition to the obex, we examined the celiac ganglion, cervical cranial ganglion, trigeminal ganglion and proximal ganglion of the vagus nerve using histological techniques. Unexpectedly, we found a high number of neurofibroma, a benign peripheral nerve sheath tumor consisting of Schwann cells, fibroblasts and perineural cells. The neurofibroma were present only in the celiac ganglion and found during histologic examination. With a frequency of 9.91% in BSE cattle and their cohorts (case animals) and 9.09% in the age, breed and district matched control animals there seems to be no correlation between the occurrence of BSE and neurofibroma. Benign peripheral nerve sheath tumors have been described more often in cattle than in other domestic animals. Usually, they are incidental macroscopic findings in the thoracic ganglia during meat inspection. To our knowledge, there are no previous systematic histologic studies including bovine celiac ganglia at all. The high incidence of celiac ganglia neurofibroma may play a role in the frequently occurring abomasal displacements in Holstein Frisian cattle as the tumors might cause a gastrointestinal motility disorder. At present a genetic predisposition for these neoplasms cannot be ruled out.

Genetically engineered minipigs model the major clinical features of human neurofibromatosis type 1

Neurofibromatosis Type 1 (NF1) is a genetic disease caused by mutations in Neurofibromin 1 (NF1). NF1 patients present with a variety of clinical manifestations and are predisposed to cancer development. Many NF1 animal models have been developed, yet none display the spectrum of disease seen in patients and the translational impact of these models has been limited. We describe a minipig model that exhibits clinical hallmarks of NF1, including café au lait macules, neurofibromas, and optic pathway glioma. Spontaneous loss of heterozygosity is observed in this model, a phenomenon also described in NF1 patients. Oral administration of a mitogen-activated protein kinase/extracellular signal-regulated kinase inhibitor suppresses Ras signaling. To our knowledge, this model provides an unprecedented opportunity to study the complex biology and natural history of NF1 and could prove indispensable for development of imaging methods, biomarkers, and evaluation of safety and efficacy of NF1-targeted therapies.

Oral Manifestations and Molecular Basis of Oral Genodermatoses: A Review

Genodermatoses refers to group of inherited monogenic disorders with skin manifestations. Many of these disorders are rare and also have oral manifestations, called oral genodermatoses. This article provides a focused review of molecular basis of important genodermatoses that affects the oral cavity and also have prominent associated dermatologic features. In several conditions discussed here, the oral findings are distinct and may provide the first clue of an underlying genetic diagnosis. The article also emphasises on the prenatal diagnosis, genetic counselling and the treatment oral genodermatoses.

Neurofibromatosis: an update of ophthalmic characteristics and applications of optical coherence tomography

Neurofibromatosis (NF) is a multisystem disorder and tumor predisposition syndrome caused by genetic mutation on chromosome 17-17q11.2 in NF type 1 (NF1), and on chromosome 22-22q12.2 in NF type 2. The disorder is characterized by considerable heterogeneity of clinical expression. NF1 is the form with the most characteristic ocular manifestations. Lisch nodules of the iris are among the well-known diagnostic criteria for the disease. Glaucoma and associated globe enlargement have been described in a significant proportion of patients with NF1 and orbital-facial involvement. Optic nerve glioma may cause strabismus and proptosis, and palpebral neurofibroma may reach considerable size and occasionally show malignant transformation. Near infrared reflectance has greatly contributed to enhancing our knowledge on choroidal alterations in NF1. Indeed, some authors have proposed to include these among the diagnostic criteria. Optical coherence tomography has given new insight on retinal alterations and is a noninvasive tool in the management of optic nerve gliomas in children. Ocular manifestations in NF type 2 can range from early-onset cataracts in up to 80% of cases to optic nerve hamartomas and combined pigment epithelial and retinal hamartomas.

Clinical features of spinal schwannomas in 65 patients with schwannomatosis compared with 831 with solitary schwannomas and 102 with neurofibromatosis Type 2: a retrospective study at a single institution

OBJECTIVE

The aim of this study was to evaluate the clinical features of spinal schwannomas in patients with schwannomatosis and compare them with a large cohort of patients with solitary schwannomas and neurofibromatosis Type 2 (NF2).

METHODS

The study was a retrospective review of 831 patients with solitary schwannomas, 65 with schwannomatosis, and 102 with NF2. The clinical, radiographic, and pathological data were extracted with specific attention to the age at onset, location of tumors, initial symptoms, family history, and treatment outcome.

RESULTS

The male-to-female ratio of patients with schwannomatosis (72.3% vs 27.7%) was significantly higher than that of patients with solitary schwannomas (53.3% vs 46.7%) and NF2 (54.0% vs 46.0%), respectively (chi-square test, p = 0.012). The mean age at the first spinal schwannoma operation of patients with NF2 (24.7 ± 10.2 years) was significantly younger than that of patients with solitary schwannomas (44.8 ± 13.2 years) and schwannomatosis (44.4 ± 14.1 years; 1-way ANOVA, p < 0.001). The initial symptoms were similar among the 3 groups, with pain being the most common. The distribution of spinal tumors among the 3 groups was significantly different. The peak locations of spinal schwannomas in patients with solitary schwannomas were at C1-3 and T12-L3; in schwannomatosis, the peak location was at T12-L5. A preferred spinal location was not evident for intradural-extramedullary tumors in NF2. Only a slight prominence in the lumbar area could be observed. The patients in the 3 groups obtained similar benefits from the operation; the recovery rates in the patients with solitary schwannomas, NF2, and schwannomatosis were 50.1%, 38.0%, and 53.9%, respectively. The prognosis varied among spinal schwannomas in the patients with schwannomatosis. Up until the last date of follow-up, most patients with schwannomatosis (81.5%) had undergone a single spinal operation, but 12 patients (18.5%) had undergone multiple spinal operations. Patients with nonsegmental schwannomatosis or those with early onset disease seemed to have a poor prognosis; they were more likely to undergo multiple spinal operations. Small cauda equina nodules were common in patients with schwannomatosis (46.7%) and NF2 (86.9%); these small schwannomas appeared to have relatively static behavior. Two patients suspicious for schwannomatosis were diagnosed with NF2 with the detection of constitutional NF2 mutations; 1 had unilateral vestibular schwannoma, and the other had suspicious bilateral trigeminal schwannomas.

CONCLUSIONS

The clinical features of spinal schwannomas vary among patients with solitary schwannomas, NF2, and schwannomatosis. Spinal schwannomas of patients with NF2 appear to be more aggressive than those in patients with solitary schwannomas and schwannomatosis. Spinal schwannomas of schwannomatosis predominate in the lumbar area, and most of them can be treated successfully with surgery. The prognosis varies among spinal schwannomas of schwannomatosis; some patients may need multiple operations due to newly developed schwannomas. Sometimes, it is difficult to differentiate schwannomatosis from NF2 based on clinical manifestations. It is prudent to perform close follow-up examinations in patients with undetermined schwannomatosis and their offspring.

Neurofibromatosis type 1 and chronic neurological conditions in the United States: an administrative claims analysis

PURPOSE

Neurofibromatosis type 1 has been linked to several neurological conditions, including epilepsy, Parkinson disease, headache, multiple sclerosis, and sleep disturbances, predominantly through case reports and patient series that lack comparison groups. Our objective was to assess whether specific neurological conditions occur more frequently in individuals with neurofibromatosis type 1 versus those without neurofibromatosis type 1.

METHODS

We used the 2006-2010 MarketScan Commercial Claims and Encounters database to examine associations between neurological conditions and neurofibromatosis type 1. The neurofibromatosis type 1 group was identified through ≥2 International Classification of Diseases, Ninth Revision, Clinical Modification neurofibromatosis codes (237.70, 237.71) occurring ≥30 days apart or one inpatient neurofibromatosis code. A nonneurofibromatosis type 1 comparison group was frequency matched to the neurofibromatosis type 1 group on age and enrollment length at a 10:1 ratio. Unconditional logistic regression was employed to calculate adjusted odds ratios and 95% confidence intervals for associations between neurofibromatosis and neurological conditions.

RESULTS

Compared with the nonneurofibromatosis type 1 group (n = 85,790), the neurofibromatosis type 1 group (n = 8,579) had significantly higher odds of health insurance claims for epilepsy (odds ratio: 7.3; 95% confidence interval: 6.4-8.3), Parkinson disease (odds ratio: 3.1; 95% confidence interval: 1.3-7.5), headache (odds ratio: 2.9; 95% confidence interval: 2.6-3.1), multiple sclerosis (odds ratio: 1.9; 95% confidence interval: 1.2-2.9), and sleep disturbances/disorder (odds ratio: 1.4; 95% confidence interval: 1.2-3.6).

CONCLUSION

This large study provides strong evidence for positive associations between several neurological conditions and neurofibromatosis type 1.

Familial syndromes associated with intracranial tumours: a review

BACKGROUND

Most cancers of the central nervous system (CNS) occur sporadically in the absence of any known underlying familial disorder or multi-systemic syndrome. Several syndromes are associated with CNS malignancies, however, and their recognition has significant implications for patient management and prognosis. Patients with syndrome-associated CNS malignancies often have multiple tumours (either confined to one region or distributed throughout the body), with similar or different histology.

OBJECTIVE

This review examines syndromes that are strongly associated with CNS cancers: the phakomatosis syndromes, familial syndromes such as Li-Fraumeni and familial polyposis syndromes and dyschondroplasia.

Schwannomatosis presenting as pancreatic and submandibular gland schwannoma

Schwannomatosis is a well-established third form of neurofibromatosis, characterized by the presence of multiple non-vestibular, non-intradermal schwannomas, often associated with chronic pain. Herein, we report a 41-year-old man with a history of paternal neurofibromatosis 1, who presented with partially cystic tumors in the pancreas and in the right submandibular gland. Besides, he complained of neuropathic pain in the right inguinal and suprapubic area. Magnetic resonance imaging revealed multiple intradural-extramedullary tumors at the cervical, thoracic and lumbar spinal canal, suggestive of schwannomas. The vestibular nerves were not involved. Pathological examination of the glandular tumors disclosed benign schwannomas. These tumors had substantial myxoid stroma and prominent cystic change, and showed a mosaic pattern of loss of INI1/SMARCB1 expression by immunohistochemistry. Later, the patient developed three nodules in the right lung which were interpreted as schwannomas. To our knowledge, this is the first report of schwannomatosis presenting as pancreatic and salivary gland schwannomas.

A differential diagnosis of inherited endocrine tumors and their tumor counterparts

Inherited endocrine tumors have been increasingly recognized in clinical practice, although some difficulties still exist in differentiating these conditions from their sporadic endocrine tumor counterparts. Here, we list the 12 main topics that could add helpful information and clues for performing an early differential diagnosis to distinguish between these conditions. The early diagnosis of patients with inherited endocrine tumors may be performed either clinically or by mutation analysis in at-risk individuals. Early detection usually has a large impact in tumor management, allowing preventive clinical or surgical therapy in most cases. Advice for the clinical and surgical management of inherited endocrine tumors is also discussed. In addition, recent clinical and genetic advances for 17 different forms of inherited endocrine tumors are briefly reviewed.

Canonical Wnt/β-catenin signaling drives human schwann cell transformation, progression, and tumor maintenance

Genetic changes required for the formation and progression of human Schwann cell tumors remain elusive. Using a Sleeping Beauty forward genetic screen, we identified several genes involved in canonical Wnt signaling as potential drivers of benign neurofibromas and malignant peripheral nerve sheath tumors (MPNSTs). In human neurofibromas and MPNSTs, activation of Wnt signaling increased with tumor grade and was associated with downregulation of β-catenin destruction complex members or overexpression of a ligand that potentiates Wnt signaling, R-spondin 2 (RSPO2). Induction of Wnt signaling was sufficient to induce transformed properties in immortalized human Schwann cells, and downregulation of this pathway was sufficient to reduce the tumorigenic phenotype of human MPNST cell lines. Small-molecule inhibition of Wnt signaling effectively reduced the viability of MPNST cell lines and synergistically induced apoptosis when combined with an mTOR inhibitor, RAD-001, suggesting that Wnt inhibition represents a novel target for therapeutic intervention in Schwann cell tumors.

Spinal cord tumours: advances in genetics and their implications for treatment

Tumours of the spinal cord, although rare, are associated with high morbidity. Surgical resection remains the primary treatment for patients with this disease, and offers the best chance for cure. Such surgical procedures, however, carry substantial risks such as worsening of neurological deficit, paralysis and death. New therapeutic avenues for spinal cord tumours are needed, but genetic studies of the molecular mechanisms governing tumourigenesis in the spinal cord are limited by the scarcity of high-quality human tumour samples. Many spinal cord tumours have intracranial counterparts that have been extensively studied, but emerging data show that the tumours are genetically and biologically distinct. The differences between brain and spine tumours make extrapolation of data from one to the other difficult. In this Review, we describe the demographics, genetics and current treatment approaches for the most commonly encountered spinal cord tumours--namely, ependymomas, astrocytomas, haemangioblastomas and meningiomas. We highlight advances in understanding of the biological basis of these lesions, and explain how the latest progress in genetics and beyond are being translated to improve patient care.

Dermatologic manifestations of endocrine disorders

PURPOSE OF REVIEW

The diagnosis of many childhood endocrine disorders can be facilitated by an awareness of the associated dermatologic findings. In this review, we will survey examples of endocrine disorders in children that include a prominent or diagnostic dermatologic sign/symptom.

RECENT FINDINGS

A key concept is that skin findings often accompany hormonal conditions, both those of hormone excess and hormone deficiency/resistance. Some dermatologic signs may also represent the hallmark lesion, or provide the first clinical sign in childhood, for both familial tumoral and nontumoral syndromes. Moreover, skin as an endocrine organ itself may provide new avenues both to understand disease mechanisms as well as to provide targeted therapy.

SUMMARY

Early diagnosis, often aided by recognition of a keynote dermatologic lesion, may permit prompt, timely treatment that, in some cases, may even prove life saving. Conversely, when these associated signs go undetected or misdiagnosed, therapeutic intervention may be delayed unnecessarily.

Tumors of central and peripheral nervous system associated with inherited genetic syndromes

There are several genetic syndromes that predispose to the development of tumors of the nervous system. In the present study, we provide a review of the tumors that are associated with neurofibromatosis type 1, neurofibromatosis type 2, tuberous sclerosis complex, von Hippel-Lindau disease, Li-Fraumeni syndrome, Cowden disease, Turcot syndrome, nevoid basal cell carcinoma syndrome (Gorlin syndrome) and rhabdoid predisposition syndrome, which are the most common.