Patient characteristics, treatment patterns, healthcare resource utilization, and costs among patients diagnosed with neurofibromatosis type 1 with and without plexiform neurofibromas in Japan

OBJECTIVES

The objectives of this study were to retrospectively investigate the patient characteristics, treatment patterns, healthcare resource utilization (HCRU), and healthcare costs related to management of neurofibromatosis type 1 (NF1) in Japan.

METHODS

Cohorts of NF1 patients with or without plexiform neurofibromas (PN) were identified from the Medical Data Vision database in 2008-2019. Baseline characteristics, NF1 medications, HCRU, and associated costs were assessed using descriptive statistics. All-cause HCRU and costs following the first confirmed NF1 diagnosis date were analyzed per patient per year (PPPY) in Japanese Yen (JPY) and United States Dollar (USD).

RESULTS

A total of 4394 NF1 patients without PN and 370 NF1 patients with PN were identified. The mean age was 35.0 and 36.9 years, respectively. The proportion of patients with PN treated with medications was higher than that in patients without PN (except for antirheumatic/immunologic agents). Analgesics/non-steroidal anti-inflammatory drugs were the most frequently prescribed NF1 medications (44.3% and 56.0% in patients without and with PN, respectively), followed by inpatient prescriptions of opioids/opioid-like agents (17.8% and 27.6%, respectively). Inpatient admissions accounted for the highest costs in both cohorts with the average cost PPPY being JPY 2,133,277 (USD 19,861) for patients without PN and JPY 1,052,868 (USD 9802) for patients with PN.

CONCLUSIONS

NF1 is treated primarily with supportive care with analgesics/non-steroidal anti-inflammatory drugs being the most frequently prescribed NF1 medications in Japan. Findings underscored the unmet need and substantial economic burden among patients with NF1 and highlighted the need for new treatment options for patients with this disease.

The PlexiQoL, a patient-reported outcome measure on quality of life in neurofibromatosis type 1-associated plexiform neurofibroma: translation, cultural adaptation and validation into the Dutch language for the Netherlands

BACKGROUND

Half of the patients with Neurofibromatosis type 1 (NF1) develop one or more tumours called plexiform neurofibromas, which can have a significant impact on Quality of Life (QoL). The PlexiQoL questionnaire is a disease-specific QoL measure for adults with NF1-associated plexiform neurofibromas. The aim of this study was to adapt and validate a Dutch version of the PlexiQoL for the Netherlands.

METHODS

The PlexiQoL was translated using the dual-panel methodology, followed by cognitive debriefing interviews to assess face and content validity. The psychometric properties were evaluated by administering the questionnaire on two separate occasions to a sample of adults with NF1 and plexiform neurofibromas. Feasibility was evaluated by the presence of floor/ceiling effects. Reliability was assessed by evaluating Cronbach's alpha coefficient and test-retest reliability, using Spearman's rank correlation coefficients. Mann-Whitney U tests were used to check for known group validity. The Nottingham Health Profile (NHP) questionnaire was used as comparator questionnaire to evaluate convergent validity.

RESULTS

The translation and cognitive debriefing interviews resulted in a Dutch version of the PlexiQoL that reflected the original concept and underlying semantic meanings of the UK English version. Forty participants completed the validation survey. The Dutch PlexiQoL demonstrated excellent internal consistency (Cronbach's α 0.825) and test-retest reliability (Spearman correlation coefficient 0.928). The questionnaire detected differences in PlexiQoL scores between participants based on self-reported general health and disease severity. Convergent validity was confirmed for relevant NHP subsections.

CONCLUSIONS

The Dutch PlexiQoL demonstrated excellent psychometric properties and can be reliably used to measure plexiform neurofibroma-related QoL in adults with NF1 in the Netherlands.

Treatment With Selumetinib for Café-au-Lait Macules and Plexiform Neurofibroma in Pediatric Patients With Neurofibromatosis Type 1

This case report describes 4 patients with a rare autosomal dominant multisystem disorder resulting from NF1 variants that leads to café-au-lait macules and neurofibromas.

Recommendations for assessing appearance concerns related to plexiform and cutaneous neurofibromas in neurofibromatosis 1 clinical trials

BACKGROUND/AIMS

Individuals with neurofibromatosis 1 may experience changes in their appearance due to physical manifestations of the disorders and/or treatment sequelae. Appearance concerns related to these physical changes can lead to psychological distress and poorer quality of life. While many neurofibromatosis 1 clinical trials focus on assessing changes in tumor volume, evaluating patients' perspectives on corresponding changes in symptoms such as physical appearance can be key secondary outcomes. We aimed to determine whether any existing patient-reported outcome measures are appropriate for evaluating changes in appearance concerns within neurofibromatosis 1 clinical trials.

METHODS

After updating our previously published systematic review process, we used it to identify and rate existing patient-reported outcome measures related to disfigurement and appearance. Using a systematic literature search and initial triage process, we focused on identifying patient-reported outcome measures that could be used to evaluate changes in appearance concerns in plexiform or cutaneous neurofibroma clinical trials in neurofibromatosis 1. Our revised Patient-Reported Outcome Rating and Acceptance Tool for Endpoints then was used to evaluate each published patient-reported outcome measures in five domains, including (1) respondent characteristics, (2) content validity, (3) scoring format and interpretability, (4) psychometric data, and (5) feasibility. The highest-rated patient-reported outcome measures were then re-reviewed in a side-by-side comparison to generate a final consensus recommendation.

RESULTS

Eleven measures assessing appearance concerns were reviewed and rated; no measures were explicitly designed to assess appearance concerns related to neurofibromatosis 1. The FACE-Q Craniofacial Module-Appearance Distress scale was the top-rated measure for potential use in neurofibromatosis 1 clinical trials. Strengths of the measure included that it was rigorously developed, included individuals with neurofibromatosis 1 in the validation sample, was applicable to children and adults, covered item topics deemed important by neurofibromatosis 1 patient representatives, exhibited good psychometric properties, and was feasible for use in neurofibromatosis 1 trials. Limitations included a lack of validation in older adults, no published information regarding sensitivity to change in clinical trials, and limited availability in languages other than English.

CONCLUSION

The Response Evaluation in Neurofibromatosis and Schwannomatosis patient-reported outcome working group currently recommends the FACE-Q Craniofacial Module Appearance Distress scale to evaluate patient-reported changes in appearance concerns in clinical trials for neurofibromatosis 1-related plexiform or cutaneous neurofibromas. Additional research is needed to validate this measure in people with neurofibromatosis 1, including older adults and those with tumors in various body locations, and explore the effects of nontumor manifestations on appearance concerns in people with neurofibromatosis 1 and schwannomatosis.

Miniature Palpebral Plexiform Neurofibroma in Neurofibromatosis Type 2

A 27-year-old woman with well-documented neurofibromatosis 2 developed a soft, painless, nodular lesion on the skin surface of the left upper eyelid over 2 years. Following excision, histopathology revealed a plexiform neurofibroma with intradermal nodules comprised of benign round and spindle cells that reacted diffusely with immunohistochemical stains SOX-10 and S100. A subset showed focal reactivity for neurofilament and CD34. A perineurium surrounded each nodule with cells staining positively for markers EMA (epithelial membrane antigen) and GLUT1 (glucose transporter 1). Plexiform neurofibromas are rare tumors that occur in 5%-15% of patients with neurofibromatosis 1. Cutaneous abnormalities in neurofibromatosis 2 have not been widely studied although reports have described schwannomas, plexiform schwannomas, and occasional neurofibromas. Plexiform neurofibromas in neurofibromatosis 2 have rarely been illustrated and the current case represents a unique bona fide eyelid example to date.

Clinical, Radiologic, and Histopathologic Features that Distinguish a Pigmented Plexiform Neurofibroma from a Congenital Melanocytic Nevus

A 13-year-old Hispanic boy with no significant medical etymology presented with a chief complaint of widespread brown macules and patches. He had a large and evenly pigmented brown patch, with a centrally located 2.2 cm × 1.2 cm soft and darkly pigmented plaque, which became more apparent with tension applied to the surrounding skin (Figure 1). The patient's mother stated that the plaque was present since birth and had increased in size over time. The clinical differential diagnoses included a congenital melanocytic nevus (CMN), a large café au lait macule (CALM), and a Becker's nevus with a congenital smooth muscle hamartoma.

Neurofibromatosis Type I Presenting with Incomplete Ileal Volvulus in a Pediatric Patient

BACKGROUND Neurofibromatosis 1 is a neurocutaneous disorder with multisystemic manifestations. When patients are lacking overt cutaneous manifestations, diagnosis may be delayed and may complicate diagnosis and management of atypical presentations of this disease. It is thus important to strive to obtain relevant and/or complete history to arrive at the appropriate diagnosis. Furthermore, maintaining an index of suspicion in cases of vague abdominal pain may guide the clinician in establishing the correct diagnosis of mesenteric plexiform neurofibroma in the setting of known/presumed neurofibromatosis 1 patients presenting with acute and/or chronic vague abdominal symptoms. CASE REPORT This is a case of a teenage boy who presented with acute, vague abdominal pain over a period of 2 weeks. Laboratory tests and physical exam findings in primary and secondary care settings were unremarkable, and thus the patient was discharged home only to continue with abdominal pain, thus seeking additional medical care. After admission to our facility and exhaustive history taking, physical examination, and imaging, a prospective diagnosis of neurofibromatosis with mesenteric neurofibroma was made. Upon surgical exploration, a mesenteric mass with corresponding volvulized, ischemic small bowel was removed. Histopathology confirmed a plexiform neurofibroma. The patient recovered adequately and was discharged home without complications. CONCLUSIONS This case highlights the importance of exhaustive history taking to obtain an accurate diagnosis as well as the importance of a high index of clinical suspicion for mesenteric neurofibromatosis in patients with presumed or known neurofibromatosis and presenting with vague abdominal symptoms.

Solitary Intrascrotal Plexiform Neurofibroma in a 10-Year-Old Male

Intrascrotal neurofibromas are extensive tumors that grow from peripheral nerves within the scrotum and are exceedingly rare among the benign extratesticular tumors. Though the risk is low, potential for malignancy and patient discomfort make diagnosis and surgical evaluation imperative. Pediatric neurofibromas are typically only associated with neurofibromatosis type 1. However, herein, we describe a rare case of a benign, intrascrotal plexiform neurofibroma in a 10-year-old male who lacks any stigmata associated with this genetic disorder. Diagnostic and surgical challenges as well as histopathological findings are discussed.

Selumetinib in the Treatment of Orbital Plexiform Neurofibroma: A Case Report

A 4-year-old boy with a known diagnosis of neurofibromatosis 1 (NF1) and a diffusely infiltrative plexiform neurofibroma (PN) of the left orbit was started on selumetinib treatment for progressively worsening amblyopia. The patient first presented with new-onset left ptosis at 11 months old. He subsequently developed refractory anisometropic amblyopia of the left eye, in addition to clinically significant left proptosis and hypoglobus that interfered with glasses wear for his amblyopia treatment. The plexiform neurofibroma was not amenable to surgical resection and selumetinib treatment was initiated 3 years after the initial diagnosis. The patient showed remarkable clinical and radiographic improvement in tumor burden after treatment. Best corrected visual acuity improved from 20/50 to 20/20- in his amblyopic eye. Relative proptosis of the affected eye also improved from 4mm to 2mm on Hertel measurements, which allowed for consistent glasses wear. Adverse effects from the treatment were limited to an acneiform rash, which resolved following dose reduction according to the FDA dosing guidelines.

[Neurofibromatosis type 1 : From diagnosis to follow-up]

BACKGROUND

Neurofibromatosis type 1 (NF1) is a tumor predisposition syndrome and is one of the most common genetic diseases. It is therefore a condition encountered by radiologists in clinical routine. Since the variability of the clinical expression is very high and several organ systems are affected, we present a standardized diagnostic approach in this article.

METHODS

Evaluation of the literature on neurofibromatosis type 1 in the context of radiological examination methods.

RESULTS

In addition to the frequently known changes in the central and peripheral nervous system such as optic gliomas and plexiform neurofibromas, lesions from the orthopedic spectrum and vascular changes must also be included in the radiological diagnosis.

CONCLUSIONS

Due to the diversity of the clinical picture of NF1, it is reasonable to define an examination strategy which takes into account the needs of radiological routine and also reliably detects the most frequent and prognostically significant pathologies accompanying this disease. In this article, the current recommendations for diagnosis of neurofibromatosis-associated tumors and skeletal changes are summarized, and examination protocols and time intervals are suggested.

RETRACTED: A case report of a 4-year-old girl with neurofibromatosis type 1

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Authors. A diagnostic discordance in the original pathology reports has been noticed and requires further evaluation, therefore the paper will be retracted.

Cell-free DNA ultra-low-pass whole genome sequencing to distinguish malignant peripheral nerve sheath tumor (MPNST) from its benign precursor lesion: A cross-sectional study

BACKGROUND

The leading cause of mortality for patients with the neurofibromatosis type 1 (NF1) cancer predisposition syndrome is the development of malignant peripheral nerve sheath tumor (MPNST), an aggressive soft tissue sarcoma. In the setting of NF1, this cancer type frequently arises from within its common and benign precursor, plexiform neurofibroma (PN). Transformation from PN to MPNST is challenging to diagnose due to difficulties in distinguishing cross-sectional imaging results and intralesional heterogeneity resulting in biopsy sampling errors.

METHODS AND FINDINGS

This multi-institutional study from the National Cancer Institute and Washington University in St. Louis used fragment size analysis and ultra-low-pass whole genome sequencing (ULP-WGS) of plasma cell-free DNA (cfDNA) to distinguish between MPNST and PN in patients with NF1. Following in silico enrichment for short cfDNA fragments and copy number analysis to estimate the fraction of plasma cfDNA originating from tumor (tumor fraction), we developed a noninvasive classifier that differentiates MPNST from PN with 86% pretreatment accuracy (91% specificity, 75% sensitivity) and 89% accuracy on serial analysis (91% specificity, 83% sensitivity). Healthy controls without NF1 (participants = 16, plasma samples = 16), PN (participants = 23, plasma samples = 23), and MPNST (participants = 14, plasma samples = 46) cohorts showed significant differences in tumor fraction in plasma (P = 0.001) as well as cfDNA fragment length (P < 0.001) with MPNST samples harboring shorter fragments and being enriched for tumor-derived cfDNA relative to PN and healthy controls. No other covariates were significant on multivariate logistic regression. Mutational analysis demonstrated focal NF1 copy number loss in PN and MPNST patient plasma but not in healthy controls. Greater genomic instability including alterations associated with malignant transformation (focal copy number gains in chromosome arms 1q, 7p, 8q, 9q, and 17q; focal copy number losses in SUZ12, SMARCA2, CDKN2A/B, and chromosome arms 6p and 9p) was more prominently observed in MPNST plasma. Furthermore, the sum of longest tumor diameters (SLD) visualized by cross-sectional imaging correlated significantly with paired tumor fractions in plasma from MPNST patients (r = 0.39, P = 0.024). On serial analysis, tumor fraction levels in plasma dynamically correlated with treatment response to therapy and minimal residual disease (MRD) detection before relapse. Study limitations include a modest MPNST sample size despite accrual from 2 major referral centers for this rare malignancy, and lack of uniform treatment and imaging protocols representing a real-world cohort.

CONCLUSIONS

Tumor fraction levels derived from cfDNA fragment size and copy number alteration analysis of plasma cfDNA using ULP-WGS significantly correlated with MPNST tumor burden, accurately distinguished MPNST from its benign PN precursor, and dynamically correlated with treatment response. In the future, our findings could form the basis for improved early cancer detection and monitoring in high-risk cancer-predisposed populations.

Limitations and benefits of FDG-PET/CT in NF1 patients with nerve sheath tumors: A cross-sectional/longitudinal study

The purposes of this study were to re-confirm the usefulness of PET/CT in the differentiation of benignity/malignancy of neurogenic tumors in NF1 patients, and to analyze the natural course of plexiform neurofibroma (pNF) and clarify whether PET/CT is also useful for detecting tumors other than neurogenic tumors. PET/CT was prospectively imaged in 36 NF1 patients. There were 14 malignant peripheral nerve sheath tumors (MPNSTs) in 14 patients, and 54 pNFs in 30 patients. Nine patients had both MPNST and pNF. Maximal standardized uptake value (SUVmax) was significantly higher in MPNST (median 7.6: range 4.1-10.4) (P < .001) compared with that of pNF (median 3.7: range 1.6-9.3). The cut-off value of 5.8 resulted in a sensitivity of 78.6% and specificity of 88.9%. Median age was 29 y, and median maximum tumor diameter was 82 mm in 14 MPNST patients. The 5-y overall survival rate was 46.8%. Three patients with low-grade MPNST were alive without disease at the time of this report. In 9 patients in which pNF and MPNST co-existed, 2 showed a higher SUVmax of pNF than that of MPNST. Natural history analysis of pNF (n = 43) revealed that no factors significantly correlated with increased tumor size. Nine lesions other than neurogenic tumors were detected by PET/CT including 5 thyroid lesions and 3 malignant neoplasms. This study revealed the usefulness and limitation of PET/CT for NF1 patients. In the future, it will be necessary to study how to detect over time the malignant transformation of pNF to MPNST, via an intermediate tumor.

Esthetic subunit approach in massive facial plexiform neurofibroma: a case report

Plexiform neurofibroma is a presentation of neurofibromatosis type 1 (NF1) which can cause great facial deformities. Treatment rarely has a healing effect, so the surgical approach is aimed at improving esthetics and function. It requires a cross-disciplinary approach and typically needs multi-stage surgery. This is the case of a 16-year-old male patient with NF1 presenting with left periorbital and malar facial plexiform neurofibroma with slow-growth intraconal and extraconal invasion. He presented at the plastic surgery consultation for facial soft tissue deformity correction. Removal was performed using an esthetic subunit approach, with canthopexy and orbital cavity reconstruction, resulting in facial region symmetrization. This allowed for remarkable esthetic and functional improvement, facilitating ocular prosthesis adaptation. The subsequent use of selumetinib allowed the lesion to be stabilized.

Predictors of cognitive development in children with neurofibromatosis type 1 and plexiform neurofibromas

AIM

To describe the cognitive development of children with neurofibromatosis type 1 (NF1) and plexiform neurofibromas, and identify predictors of cognitive development.

METHOD

Participants included 88 children with NF1 and plexiform neurofibromas (50 males, 38 females, aged 6-18y, mean=12y, SD=3y 7mo) on a natural history study at the National Cancer Institute. Neuropsychological assessments (e.g. IQ, academic achievement, attention, and executive functioning) were administered three times over 6 years.

RESULTS

Relative to normative peers, the total sample of children with NF1 and plexiform neurofibromas demonstrated significantly lower scores in most cognitive domains and decreasing z-scores over time in math, writing, inhibitory control, and working memory. Children who had parents with (vs without) NF1 were more likely to experience decreased z-scores in performance IQ, reading, writing, attention, and working memory. Higher (vs lower) parental education was related to higher levels of IQ, math, reading, and cognitive flexibility and a slower decrease in math z-scores. Children's sex and the number of NF1 disease-related complications were not related to most cognitive outcomes.

INTERPRETATION

Children with NF1 and plexiform neurofibromas are at high risk for cognitive difficulties and declining z-scores in various domains of cognitive functioning over time. The findings highlight the need for a better understanding of the within-group differences in these children and their need for individualized educational plans.

WHAT THIS PAPER ADDS

Math, writing, inhibitory control, and working memory scores decreased over time. The proportion of children with clinically significant cognitive deficits increased over time. Parental neurofibromatosis type 1 and low education were related to greater cognitive difficulties in children.

A 15-Month-Old Girl Presenting With Clitoromegaly and a Chest Mass

A 15-month-old girl was initially referred for endocrine evaluation for clitoromegaly and subsequently found to have an adrenal mass that tracked along the paravertebral region and was associated with increased vascular markings along the skin. Neurologic examination was normal. Magnetic resonance imaging of the chest mass demonstrated a serpiginous lesion along the intercostal margins. Initial differential diagnosis included neuroblastoma, ganglioneuroblastoma, vascular lesion, or nerve sheath tumor. Biopsy was consistent with plexiform neurofibroma. Subsequent examination revealed features consistent with neurofibromatosis type 1. A review of clinical features of NF1 is provided in the case report.

Large penile plexiform neurofibroma in an 11-year old boy

Background

Neurofibromatosis is a genetically inherited disorder of the nervous system (brain and spinal cord) which mainly affects the development of nerve (neural) cell tissues, causing tumors (neurofibromas) to develop on nerves. It is the most common single gene disorder of the nervous system and inheritance is through autosomal dominance. They are usually classified into types 1 and 2, the type 1 is the commoner type and also known as superficial neurofibroma. Plexiform neurofibromas are the next most common type of tumor in individuals with type 1 neurofibroma. Plexiform neurofibromas are histologically benign tumors that are made up of a variety of cell types including neuronal axons, Schwann cells, fibroblasts, mast cells, macrophages, perineural cells and extracellular matrix materials such as collagen. They can occur in any part of the body and can grow throughout the person's lifetime, often becoming disfiguring, disabling or deadly via compression of vital structures or conversion to a malignant sarcoma or malignant peripheral nerve sheath turmor. The aim of this report is to present a large penile plexiform neurofibroma which required extensive dissection for complete excision and reconstruction of the phallus and glans penis.

Objectives

To present a huge penile plexiform neurofibroma and the mode of surgical treatment.

Methods

The huge penile plexiform neurofibroma was completely excised and the penile defect resulting from the excision was repaired.

Conclusion

Plexiform neurofibromas are congenital tumors of peripheral nerve sheaths which may also develop near nerve roots deep within the body. They are usually benign but carry a malignant potential in 5-10% of patients. Plexiform neurofibromas are commoner in the face, chest and limbs but the index case occurred on the penile shaft.

Unanticipated Compression of the Trachea in a 5-Month-Old Undergoing an MRI for Evaluation of Neurofibromatosis

Neurofibromatosis type 1 is an autosomal-dominant disorder with the tendency toward the formation of tumors. Plexiform neurofibromas are the most common type of tumors seen in neurofibromatosis type 1. Approximately 50% occur in the head and neck region with a 5% incidence of airway involvement. We describe the case of a 5 month old with a plexiform neurofibroma of the neck who developed complete airway obstruction on induction of anesthesia. Magnetic resonance imaging revealed a skull base neurofibroma extending to the hypopharynx and resulting in deviation of the airway. Because of the possibility of airway involvement, a careful preanesthetic evaluation as well as a slow induction with the maintenance of spontaneous ventilation should be considered in patients presenting with facial neurofibromas.

[Enophthalmos in an orbital tumor]

Enophtalmus is an unusual sign of the orbital tumors often represented by proptosis. One patient with enophtalmus and intraorbital tumor and aplasy is presented. The treatment of choice of orbital tumor is complete surgical excision and careful follow-up. Considering the more aggressive course followed by recurrent tumor, correct diagnosis and management is essential.

Surgery for atypical plexiform neurofibromas of the trunk in NF1 with high standardised uptake value (SUV) in positron-emission tomography (PET) expressing podoplanin: a long-term follow-up

A 23-year-old female with an established diagnosis of neurofibromatosis type 1 (NF1) was found to have two tumours in her trunk. These showed high uptake value in positron-emission/computerized tomography (PET) scans, and were suspected to be malignant peripheral nerve sheath tumours (MPNST). The extirpated tumours proved to be atypical plexiform neurofibromas. Slight to moderate podoplanin expression of the tumour cells was noted in areas of fibrillary growth. Six years following surgery, there is neither evidence of local tumour recurrence nor development of MPNST. Current studies on atypical neurofibroma in NF1 suggest podoplanin expression in subtypes of transformed Schwann cells, resembling schwannoma-like areas in neurofibroma. This marker may be useful in distinguishing different Schwann cell populations in NF1.

[Magnetic resonance imaging findings of orbital disease in neurofibromatosis type 1 patients]

OBJECTIVE

To explore the magnetic resonance imaging (MRI) features of neurofibromatosis type 1 (NF1) with orbital involvement.

METHODS

We retrospectively reviewed the MRI findings of orbital abnormalities in 80 NF1 patients (86 orbits). The diagnosis was confirmed by the updated National Institute of Health (NIH) criteria. All of them underwent MRI scans of orbit or brain while 71 patients had contrast enhancement.

RESULTS

The orbital abnormalities were documented in 80 patients. And 79 cases (85 orbits) had plexiform neurofibroma in orbit and/or adjacent regions. The orbital involvements extended to superficial temporal fossa (n = 61), infratemporal fossa (n = 31), cavernous sinus (n = 61) and pterygopalatine fossa (n = 51). There was mild-to-moderate enhancement in 71 orbits on contrast-enhanced MRI examinations. There were localized defects of orbital walls because of sphenoid bone dysplasia of greater wing (n = 79), sphenoid bone dysplasia of lesser wing (n = 72), augmentation (glaucoma) of eyeballs (n = 32) and optic nerve gliomas (n = 5). And 53 cases had hyperintense lesions on T2-weighted brain images.

CONCLUSION

Orbital involvement is common for NF1. And MRI is a useful tool of evaluating the extent of involvements and other abnormalities in the NF1 patients.

[Neurofibroma of the larynx in a nine month-old child]

Neurofibroma of the larynx is a very rare condition. A nine month-old boy presented with airway obstruction due to a plexiform neurofibroma of the larynx. It also involved the proximal part of trachea and hypopharynx. Surgical excision was not a possibility. A tracheotomy was performed in order to secure the airways. The patient was doing well afterwards and has been followed with an MRI scan twice a year. Though neurofibroma of the larynx is rare, it should be considered when diagnosing of children with airway obstruction. Long-term follow-up is essential due to risk of malignant transformation.

[A rare cutaneous congenital sarcoma: plexiform fibrohistiocytic tumor]

We report the unusual case of a three-year-old girl which presented since birth a pigmented tumor of the left side 0.5cm in diameter. Surgical removal was decided given the hypothesis of a congenital naevo-cellular naevus. The histological study ended with the diagnosis of plexiform fibrohistiocytic tumor (PFHT). Two other congenital PFHT have been reported until now. PFHT is a rare mesenchymal neoplasm of intermediate malignancy, first reported by Enzinger and Zhang in 1988 which may be difficult to diagnose, because of its low frequency, particulary in congenital cases. It is important to distinguish it from others childhood cutaneous tumors (particulary plexiform neurofibroma, cellular neurothekeoma, infantile myofibromatosis, and fibrous hamartoma). The tumor has a high local recurrence rate and complete surgical resection of the tumor, with wider margins, is required.

Dysplasia of the orbit and adjacent bone associated with plexiform neurofibroma and ocular disease in 42 NF-1 patients

Neurofibromas are the hallmark of neurofibromatosis type 1 (NF1). Interestingly, generalised and localised interference or dysfunction of bone is also a key element of the NF1 phenotype. In the skull, NF1-associated orbital dysplasia often results in a severe disfigurement of affected individuals. However, the underlying pathology of orbital dysplasia is a complex phenomenon and up to now poorly understood. This study was performed to describe the orbit in 42 NF1 patients with large, disfiguring soft-tissue tumour of the orbital/eyelid region (plexiform neurofibroma (PNF)). A dysplastic orbit on the affected side was diagnosed in 80.9%. Orbital PNF extension to adjacent regions revealed a significant correlation of orbit and temporal region (0.33, p<0.034), cheek and oral cavity (0.4, p>0.011), oral cavity and nose (0.35, p<0.026), and temporal region and cheek (0.46, p<0.003). Alterations of the optic nerve and adjacent structures were identified on MRI or CT in 14 patients. On plain skull radiographs, only sphenoid wing dysplasia and ipsilateral orbital enlargement were significantly correlated (0.528, p<0.01). This study reveals PNF as the main component of soft tissue affecting eyelids and orbit in those cases, which show a soft tissue mass in the affected orbital region. The oval-shaped orbital rim, typically seen on plain skull radiographs in sagittal projections, seems to be strongly associated with the (lateral and caudal) extension of a PNF and independent from sphenoid wing dysplasia. Several factors constitute the individual orbital dysplasia, including the growth of the invasive PNF.

A study of 17 patients affected with plexiform neurofibromas in upper and lower extremities: comparison between different surgical techniques

Plexiform neurofibromas (PN) are one of the most common and severe types of neurofibroma that occur in neurofibromatosis type I. These tumours affect long portions of nerves, infiltrating the nerve and surrounding tissue thus causing significant pain, deformity and functional problems in the affected part of the body. Treatment of this variant of neurofibromas is currently surgical. The aim of this study was to analyze the surgical treatment of plexiform neurofibromas in the lower and upper extremities. The clinical pathological features of 29 neurofibromas, 12 in the upper extremities and 17 in the lower extremities, as diagnosed at the Department of Plastic and Reconstructive Surgery of University "La Sapienza" in Rome from 2000 to 2007, were reviewed. We established that subtotal and total resection without functional destruction is often possible for superficial PN.

Management of advanced laryngeal and hypopharyngeal plexiform neurofibroma in adults

Laryngeal neurofibromas are rare. The plexiform subtype is less common and often presents during childhood in association with neurofibromatosis type I. Because it is unencapsulated and more aggressive, plexiform neurofibroma presents a management dilemma. Imaging, particularly magnetic resonance imaging, can aid in diagnosing neurofibroma, differentiating the nonplexiform and plexiform subtypes, and planning the subsequent operative approach. The importance of conservative surgery to relieve symptoms, but preserve laryngopharyngeal function, and close follow-up are stressed. We report 2 adult cases of plexiform neurofibroma involving the larynx and hypopharynx and discuss the controversies in management.

Spontaneous hemorrhage simulating rapid growth of a benign subperiosteal plexiform neurofibroma

Spontaneous subperiosteal hemorrhage is a rare complication of von Recklinghausen's disease. There are few reports describing the MR imaging characteristics of this entity. Our case is unique among these as an underlying plexiform neurofibroma was visualized by MR imaging. We present a 12-year-old child with neurofibromatosis 1 who presented with a rapidly enlarging mass of the fibula. Surgery and pathology revealed subperiosteal hemorrhage into a benign, plexiform neurofibroma. The MR imaging features, pathogenesis and clinical implications of this entity are discussed. Recognition of this disease process and differentiating it from malignant transformation can prevent unnecessary surgery.

Intraorbital plexiform neurofibroma in an NF-1-negative patient

A 52-year-old patient presented with an orbital swelling and exophthalmos that enlarged over a period of about 40 years. The clinical examination showed massive exophthalmos and ptosis of the right eye without diplopia. The radiological investigation (MRI, CT and ultrasound) showed an unclear intraorbital mass with erosion of the orbital floor, infraorbital rim and orbital roof. The lesion was diagnosed histologically as a plexiform neurofibroma. The patient did not present any features of neurofibromatosis type 1 (NF-1) and molecular genetic analysis was unable to uncover a pathogenic sequence alteration in the NF-1 gene. Owing to the absence of clinical and ophthalmologic symptoms and the improbability of complete removal, the patient refused surgical intervention.

Massive plexiform neurofibroma and spinal deformity presenting as dysphagia

Dysphagia is a symptom associated with various diseases of the upper gastrointestinal and respiratory tract, and it may be the presenting symptom of numerous tumors of the head and neck. Plexiform neurofibromas (PNFs) are benign tumors of the peripheral nerves and connective tissue, which are usually associated with neurofibromatosis type 1. We present a rare case of a 52-year-old woman presenting with dysphagia and weight loss due to a massive PNF in the subcutaneous adipose tissue of the posterior neck, associated with C1-C2 dislocation, scoliosis of the vertebral column, and 2 meningoceles consistent with the diagnosis of neurofibromatosis type 1. The combination of large PNF and cervical spine dysplasia may cause compression of the upper gastrointestinal tract and chronic progressive dysphagia.

Clinical relevance of positron emission tomography and magnetic resonance imaging in the progression of internal plexiform neurofibroma in NF1

Neurofibromatosis type 1 (NF1) is a frequent and inherited disease with a predisposition for malignant peripheral nerve sheath tumor (MPNST) development. MPNST are soft tissue sarcomas that arise from peripheral nerves, being one of the most aggressive malignancies in humans with extremely poor prognosis. MPNST frequently arise from a previously undetected plexiform neurofibroma (PNF). The malignant transformation of an internal PNF to an MPNST is difficult to assess and requires advanced imaging techniques like magnetic resonance imaging or positron emission tomography. Despite the high quality of current diagnostics, the changing tumor biology inside a plexiform neurofibroma cannot currently be visualized accurately. We report 4 cases of NF1 patients with PNF who showed imaging findings suspicious for malignant degeneration, but proved to have MPNST in only one case. Three tumors might represent an intermediate type between PNF and MPNST. Ablative surgery and complete histological work-up of specimens is the only way to clarify tumor status, thereby enabling provision of adequate local treatment.

Massive plexiform neurofibromas in childhood: natural history and management issues

OBJECT

The authors review their experience with massive plexiform neurofibromas (PNs) in patients with pediatric neurofibromatosis Type 1 (NF1) to better characterize the natural history and management of these complex lesions.

METHODS

The authors performed a retrospective review of data obtained in seven patients with NF1 in whom massive PNs were diagnosed at The Hospital for Sick Children in Toronto, Ontario, Canada. These patients attended routine follow-up examinations conducted by a number of specialists, and serial neuroimaging studies were obtained to monitor disease progression. The most common presenting feature of PN was that of a painful, expanding lesion. Furthermore, two patients harbored multiple, distinct PNs affecting different body sites. With respect to management, two patients were simply observed, undergoing serial neuroimaging studies; two patients underwent biopsy sampling of their plexiform lesions; two patients underwent attempted medical treatment (farnesyl transferase inhibitor, R11577, and cyclophosphamide chemotherapy); and three patients required surgical debulking of their PNs because the massive growth of these tumors caused functional compromise. Ultimately, one patient died of respiratory complications due to progressive growth of the massive PN lesion.

CONCLUSIONS

In this review of their experience, the authors found certain features that underscore the presentation and natural history of PNs. The management of these complex lesions, however, remains unclear. Slow-growing PNs may be observed conservatively, but the authors' experience suggests that resection should be considered in selected cases involving significant deterioration or functional compromise. Nevertheless, patients with massive PNs will benefit from close surveillance by a team of specialists to monitor for ongoing disease progression.

Resection of benign sciatic notch dumbbell-shaped tumors

OBJECT

The operative management of combined intrapelvic and extrapelvic sciatic notch dumbbell-shaped tumors is challenging. The relatively rare occurrence of these tumors and the varied extent of disease have made it difficult for surgeons to establish definitive surgical indications or predict favorable neurological outcomes based on preoperative imaging data.

METHODS

In the past 3 years, the authors treated five patients presenting with radiating leg pain as a result of benign sciatic notch dumbbell-shaped tumors. These tumors in three patients with unilateral leg symptoms were considered unresectable by other neurosurgeons because of presumed direct intrinsic neural involvement. After high-resolution magnetic resonance (MR) imaging demonstrated that the extensive tumors were separate from the sciatic nerve and the lumbosacral plexus, however, these patients underwent a combined one-stage transabdominal and posterior transgluteal complete resection. Normal neurological status was maintained postoperatively in these three patients, and after more than 1 year of postoperative follow up, there were no tumor recurrences. In two patients with bilateral symptoms and extensive tumor burden, serial MR images showed that innumerable tumors directly involved the entire cross-sectional area of the sciatic nerves and extended longitudinally to the lumbosacral plexuses. Tumor debulking or resection in these patients would have resulted in neurological deficits and would not have addressed their neuropathic pain, and therefore no surgery was performed. These two patients were treated pharmacologically and advised to monitor their tumor status over the course of their lifetimes in case of malignant transformation of the tumor.

CONCLUSIONS

A combined one-stage transabdominal and transgluteal approach allows safe resection of selected benign but extensive sciatic notch tumors. High-resolution MR imaging is a useful tool in the management of these tumors because it allows the surgeon to visualize the anatomical relationships of the tumor to the sciatic nerve. The authors believe that as this imaging technology advances, it will provide surgeons with a method to predict definitively which sciatic notch tumors displace rather than directly involve the sciatic nerve, and therefore indicate which tumors can be resected safely and completely.

Pigmented plexiform neurofibroma: Distinction from a large congenital melanocytic nevus

The substantial clinical and histologic overlap between neurotized congenital melanocytic nevi and the subset of plexiform neurofibromas with hyperpigmentation and hypertrichosis of the overlying skin (pigmented neurofibroma) has led to considerable confusion in the literature. A dark-brown, hypertrichotic plaque covered much of the right lower aspect of the trunk of a 1-year-old girl with a diffuse and plexiform neurofibroma in the same area, numerous café-au-lait macules, and intertriginous freckling. The latter findings were diagnostic of neurofibromatosis-1, which was further supported by the presence of unidentified bright objects on magnetic resonance imaging of the brain. Histologic examination of the hyperpigmented plaque revealed melanocytic hyperplasia at the dermoepidermal junction and a proliferation of rounded, pigmented melanocytes dispersed individually and in occasional small nests in the papillary dermis and scattered within underlying neurofibromatous tissue. Immunohistochemical staining with A103 (Melan-A/MART-1) and PNL2 confirmed the melanocytic differentiation of the pigmented cells, whereas glial fibrillary acidic protein and Leu-7 were detected only within plexiform areas and slender neuroid spindle cells. This case draws attention to the pigmented neurofibroma as a distinct clinicopathologic entity resulting from proliferation of melanocytes and neurosustentacular cells in the setting of neurofibromatosis-1.

Solitary plexiform neurofibroma(s): role of magnetic resonance imaging

A 10-year-old boy presented with a painless progressive swelling on the nape of the neck of 8 years' duration. When the child was 1 year old, the swelling appeared as a minute raised skin eruption the size of a pearl at the back of the neck. It was painless and progressive, continuing to increase in size until it reached the size of a walnut. At age 2 years, a minor surgical intervention was undertaken to remove the swelling, but a year later, it recurred at the same site. The size continued to increase until it reached the present size. Examination of the afflicted skin surface showed the presence of a globular, nonreducible swelling measuring 7.5 cm x 5 cm located on the upper posterior portion of the neck. Both the swelling and the skin over it were mobile and nontender. Otherwise, the boy's skin surface was without blemishes. On palpation, the swelling was plexiform, resembling a bag of worms. Magnetic resonance imaging (MRI) was performed on 1.5T MR (Signa, GE Healthcare, Chalfont St Giles, England) using T1 and T2 weighted fast spin echo and short tau inversion recovery sequences in the axial and sagittal planes. The images were marked by a well-defined, homogeneous signal intensity lesion in the subcutaneous plane of the nape of the neck. The lesion appeared isointense in T1W images and hyperintense in T2W images with few flow voids within the lesion. Based on the MRI findings, a diagnosis of superficial plexiform neurofibroma was considered. Results of routine liver and kidney function blood examination tests were within normal limits. Surgical resection was done under general anesthesia. As soon as the skin was excised, the swelling started bleeding profusely, but bleeding stopped almost immediately on the complete excision of the swelling. No cavities were present in the mass, and the underlying structures were normal. The wound was closed with nonabsorbable monofilament nylon suture. The postoperative period was uneventful. In addition to initial excision biopsy, all of the resected tissue material was subjected to serial sectioning for microscopic pathologic examination. Hematoxylin- and eosin-stained sections showed unremarkable epidermis with slight hyperkeratosis. Upper dermis showed circumscribed, lobular proliferation of spindle cells in a loose fibular background distorting much of the dermis and subcutaneous fat. Subcutis showed numerous thin-walled, ectatic blood vessels lined with prominent endothelium. Intervening tissue consisted of wavy bundles of collagen lined with elongated thin cells with tapering and wavy nuclei. The nuclear chromatin was bland without significant polymorphism or raised mitotic activity. A few nerve twigs were also seen within the tumor, which was infiltrating the surrounding fat.

Cellular neurothekeoma with a plexiform morphology: a case report with a discussion of the plexiform lesions of the skin

Neurothekeoma is a rare benign dermal lesion that is commonly seen in children and teenagers. Despite its name, the true nature of this lesion is uncertain and controversial, particularly after the emergence of the cellular (spindle/epithelioid) variant. We describe the histological and immunohistochemical findings of a right thigh skin lesion in an 11-year-old girl. It consists of a dermal ill-defined plexiform mass composed of nests and fascicles of spindle cells with pale eosinophilic cytoplasm that lie within a sclerotic stroma. The immunohistochemistry shows diffuse reactivity to CD68, matrix metalloproteinase-II, CD10 and PGP9.5 with focal reactivity to CD57 and CD34. The lesion is negative for S100, factor XIIIa, smooth muscle markers and melanocytic markers. The features are compatible with a cellular variant of neurothekeoma with plexiform pattern that also exhibits an unusual pattern of fibrohistiocytic phenotype. Although such a lesion is benign, it has a wide but important differential diagnoses that are reviewed briefly together with a brief discussion about the origin of this rare entity.