A series of 146 peripheral non—neural sheath nerve tumors: 30-year experience at Louisiana State University Health Sciences Center

Neuromuscular choristoma-associated desmoid-type fibromatosis of the brachial plexus: Additional evidence to support a nerve-driven mechanism

BACKGROUND

We have recently described circumferential nerve involvement of neuromuscular choristoma associated with desmoid-type fibromatosis (NMC-DTF) in cases involving the sciatic nerve, supporting a nerve-derived mechanism for the DTF. We wondered whether a similar growth pattern occurs in cases involving the brachial plexus (BP).

METHODS

We reviewed all available magnetic resonance (MR) imaging in patients diagnosed at our institution with NMC or NMC-DTF of the BP. We also performed a literature search of patients with NMC or NMC-DTF of the BP.

RESULTS

In our clinical records, four patients with NMC of the BP were identified, and three developed NMC-DTF. All three patients had MR imaging evidence of circumferential encasement of the BP. In the literature, we identified 15 cases of NMC of the BP, of which 12 had identified NMC-DTF. Four published cases included MR images, and only two were of sufficient quality for review. The single provided image in both cases demonstrated a similar pattern of circumferential encasement of the BP by the NMC-DTF. One additional case report was published without MR images but described circumferential involvement in the surgical findings. One unpublished case of NMC-DTF of the BP from an international radiology meeting also had this circumferential pattern pattern on MRI.

CONCLUSIONS

The MRI findings of circumferential nerve involvement in patients with NMC-DTF of the BP are similar to our previously reported data in patients with NMC-DTF of the sciatic nerve, providing further imaging-based support of a nerve-driven mechanism. Clinical implications are presented based on the proposed pathogenetic mechanism.

Health-related quality of life in patients with peripheral nerve tumors: results from the German multicentric Peripheral Nerve Tumor Registry

Objective

Peripheral nerve tumors (PNTs) are rare diseases. So far, no multicenter data on diagnostics, the efficacy of treatment, long-term outcomes, and health-related quality of life (HRQoL) exist. The establishment of the Peripheral Nerve Tumor Registry (PNTR) in 2015 allows for the systematic analysis of patients with tumors associated with peripheral nerves. The present study aims to investigate the impact of PNT on an individual's HRQoL and the effect of surgery.

Methods

HRQoL was pre- and postoperatively assessed by the Euro-Qol-5D-5L (EQ-5D-5L) and Euro-Qol visual analog scale (EQ-VAS) survey in the retrospective and prospective study arm in three active participating study centers. An index was calculated based on the EQ-5D-5L for the quantification of health state (0: worst possible state of health, 1: best possible state of health). The EQ-VAS ranges from 0% (worst imaginable health status) to 100% (best possible health status). Patient characteristics (age, sex), as well as disease (histopathological entity) and treatment (pre- and postoperative symptoms, type of treatment)-specific data, were analyzed.

Results

Data from 171 patients from three high-volume centers were included, with schwannoma (70.8%, n = 121) and neurofibroma (15.8%, n = 27) being the most prevalent histopathological diagnoses. Both the median health index value (preoperative: 0.887, n = 167; postoperative: 0.910, n = 166) and the median EQ-VAS (preoperative: 75%, n = 167; postoperative: 85%, n = 166) of the entire cohort regarding all histopathological diagnosis improved significantly after surgical therapy (p < 0.001). Preoperatively, 12.3% (n = 21) reached the highest index score of 1.0 in EQ-5D-5L and 100% in the EQ-VAS score in 5.3% (n = 9) of all patients. Postoperatively, the highest index score of 1.0 and 100% in the EQ-VAS score increased significantly and were achieved in 33.3% (n = 57) and 11.1% (n = 19) of the patients, respectively (p < 0.001).

Conclusion

For the first time, our study presents multicenter data on life quality and the effect of surgery in primarily benign peripheral nerve tumors. Early surgery at a specialized center could improve neurological outcomes and, in conclusion, better QoL. In summary, surgical therapy significantly improved the entire cohort's QoL, VAS, and analgesia.

Case report: Solitary mass of the sciatic nerve confirmed as a primary extranodal manifestation of diffuse large B-cell lymphoma in a geriatric patient

Background

Neoplastic lesions affecting peripheral nerves are rare in the general population and, most often, are benign peripheral nerve sheath tumors. However, a minority of lesions represent high-grade malignancies associated with a poor prognosis, such as malignant peripheral nerve sheath tumors (MPNSTs). Very rarely, these tumors represent peripheral non-nerve sheath tumors (PNNSTs), such as hematological neoplasms that impair nerve function. These can be hard to distinguish from MPNSTs and other lesions arising from the nerve itself. In the present case report, we describe a rare case of direct infiltration of nerves by tumor cells of a hematological neoplasm.

Methods

We report the case of a 90-year-old woman with acute onset of right-sided foot palsy, sensory loss, and pain, caused by an extensive solitary mass of the sciatic nerve in the thigh. We present and discuss the clinical presentation, multimodal diagnostic procedures, and treatment.

Results

MRI of the right thigh and the caudal pelvis revealed a contrast-enhancing lesion infiltrating the sciatic nerve. Additionally performed staging imaging was non-revealing. After multidisciplinary discussion in the neuro-oncology tumor board, a MPNST was suspected and the patient underwent radical tumor resection. However, final histopathology revealed a diffuse large B-cell lymphoma (DLBCL). The patient received adjuvant palliative local radiotherapy which led to acceptable symptom control.

Conclusion

Rare PNNSTs, including extranodal manifestations of DLBCL can have similar clinical and radiological diagnostical features as PNSTs. Comprehensive diagnostic workup of contrast-enhancing lesions affecting peripheral nerves including MRI and metabolic imaging are recommended. Discussion in interdisciplinary tumor boards facilitates finding individual treatment approaches.

Case report of a primary ectopic extradural and extraspinal meningioma of the brachial plexus

Primary ectopic extradural and extraspinal meningiomas are rare. We present a unique case of this type of meningioma in the brachial plexus. A 25-year-old man consulted us because of neuropathic supraclavicular pain and the appearance of a supraclavicular mass whose volume had increased. Clinical examination found paresis of the deltoid, biceps brachii and brachialis muscles rated as M4 (MRC) and a strong Tinel sign at the supraclavicular fossa, over the palpable mass. There was no sign pointing towards central nervous system involvement or altered general condition. MRI revealed a mass measuring 53 × 24 mm invading the C5-C6 plexus roots and the primary upper trunk, but not the bone or spinal area. This lesion was hyperintense on DWI/ADC, hyperintense on T2 with hypointense spots, and hypointense on T1 with intense heterogeneous gadolinium enhancement. Excisional biopsy was done 6 months after symptoms started. The tumor had developed at the C5 root, which was fibrous and at the C6 root, which was grossly normal. Anatomical pathology confirmed the WHO grade 1 meningioma, meningothelial and psammomatous histological subtypes. At 6 months, a follow-up MRI found no postoperative tumor remnants or recurrence. During the postoperative course, persistent paralysis of the deltoid muscle at 5 months justified a nerve transfer. This is a rare case of ectopic extraspinal and extradural meningioma of the brachial plexus. The diagnosis of an ectopic meningioma must be considered when a patient presents with a brachial plexus tumor causing neurological deficits. The extradural nature is not sufficient to rule out this diagnosis.

Peripheral Nerve Sheath Tumor: A Diagnostic and Therapeutic Challenge

INTRODUCTION

Peripheral nerve tumors are a group of rare soft tissue tumors of neuro-ectodermal origin. Although the majority of them are benign in nature, up to 10% can be malignant. The symptoms depend on the site, size, and structures compressed by the tumor.

AIM

To highlight the heterogeneity of signs and symptoms and their presentations, which has often made it difficult for the attending physician to accurately diagnose and direct the patient toward appropriate treatment.

METHODS

Eight patients treated at our tertiary care hospital between 2015 and 2022 were included in this study. They were evaluated in detail. Treatment was surgical. The patients underwent complete excision of the tumor under magnification to help preserve the adjacent neurovascular bundle. All patients were followed up post-operatively to document the status of their symptoms.

RESULTS

The average duration prior to referral to our hospital was 13 months. Seven subjects had pain at presentation, one had neurological deficit. Seven also complained of swelling. Five of the eight lesions were schwannoma, two neurofibroma and one showed malignant histology. Post-operatively, Hoffman Tinel signs improved in all six subjects. five of the seven subjects were completely pain-free, and the other two had a reduction in symptoms.

CONCLUSIONS

Early diagnosis and referral to a specialist center are needed to achieve satisfactory outcomes while treating peripheral nerve tumors. Proliferative lesions should be treated surgically in specialist centers by experienced doctors with appropriate skills and equipment for microsurgical procedures to ensure full recovery.

[Interdisciplinary Treatment Of Tumorous And Tumour-Like Lesions Of Peripheral Nerves]

Tumorous or tumour-like lesions of peripheral nerves are generally rare, heterogeneous and challenging to diagnose and treat. They may become apparent by a palpable swelling (lump) near nerves, sensory and/or motor deficits, pain to touch or neuropathic pain. In 91% of cases, tumours are benign. The differentiation of entities and their characteristics as well as a function-preserving resection strategy are highly relevant. Misdiagnosis and inadequate treatment can lead to severe deficits and pain syndromes. Benign tumours include schwannomas and neurofibromas, which can occur sporadically but can also be associated with neurogenetic tumour disposition syndromes if they occur more frequently. Rarer benign nerve tumours include perineuriomas, lipomas, aggressive fibrosis (desmoid tumours), paragangliomas and haemangiomas. Ganglion cysts are described as tumour-like lesions. The association of nerve tumours with neurogenetic syndromes and the correct classification of potentially malignant lesions such as MPNST (malignant peripheral nerve sheath tumour) or intermediate stages such as ANNUBPs (atypical neurofibromatous neoplasms with unknown biological potential) pose particular challenges. Interdisciplinarity is highly relevant for clinical treatment and a correct diagnosis. The aim of our work is to provide an overview of the relevant entities, diagnostic evaluation and contemporary treatment strategies based on the current data situation and taking into account the recently published interdisciplinary AWMF S2k guideline "Diagnosis and Treatment of Peripheral Nerve Tumours".

Synovial Sarcoma in the Extremity: Diversity of Imaging Features for Diagnosis and Prognosis

Synovial sarcomas are rare and highly aggressive soft-tissue sarcomas, primarily affecting adolescents and young adults aged 15-40 years. These tumors typically arise in the deep soft tissues, often near the large joints of the extremities. While the radiological features of these tumors are not definitely indicative, the presence of calcification in a soft-tissue mass (occurring in 30% of cases), adjacent to a joint, strongly suggests the diagnosis. Cross-sectional imaging characteristics play a crucial role in diagnosing synovial sarcomas. They often reveal significant characteristics such as multilobulation and pronounced heterogeneity (forming the "triple sign"), in addition to features like hemorrhage and fluid-fluid levels with septa (resulting in the "bowl of grapes" appearance). Nevertheless, the existence of non-aggressive features, such as gradual growth (with an average time to diagnosis of 2-4 years) and small size (initially measuring < 5 cm) with well-defined margins, can lead to an initial misclassification as a benign lesion. Larger size, older age, and higher tumor grade have been established as adverse predictive indicators for both local disease recurrence and the occurrence of metastasis. Recently, the prognostic importance of CT and MRI characteristics for synovial sarcomas was elucidated. These include factors like the absence of calcification, the presence of cystic components, hemorrhage, the bowl of grape sign, the triple sign, and intercompartmental extension. Wide surgical excision remains the established approach for definitive treatment. Gaining insight into and identifying the diverse range of presentations of synovial sarcomas, which correlate with the prognosis, might be helpful in achieving the optimal patient management.

Femoral intraneural ganglion cyst: the first confirmed case report

BACKGROUND

Ganglion cysts affecting nerve are rare causes of neuropathy. The formation of intraneural ganglion cysts, once controversial, has recently been clarified. We describe the first modern description of a femoral intraneural ganglion cyst at the hip region.

METHODS

A patient presented with a 1 year history of radiating pain, quadriceps weakness and anteromedial leg numbness was found to have a femoral intraneural cyst with a hip joint connection on MRI.

RESULTS

Surgical disconnection of the articular branch led to improvement of the neuropathy and resolution of the cyst on postoperative MRI.

CONCLUSIONS

The unifying articular (synovial) theory describes the joint origin of intraneural cysts, even when they occur in unusual locations, and their propagation into the parent nerve. Knowledge of this theory can improve outcomes; surgery needs to address the joint origin or capsulolabral defect lest recurrence ensue.

Tumors of the brachial plexus region: A 15-year experience with emphasis on motor and pain outcomes and literature review

Background

Brachial plexus region tumors are rare. In this study, we reviewed our experience with resection of tumors involving or adjacent to the brachial plexus to identify patterns in presentation and outcome.

Methods

We report a retrospective case series of brachial plexus tumors operated on by a single surgeon at a single institution over 15 years. Outcome data were recorded from the most recent follow-up office visit. Findings were compared to a prior internal series and comparable series in the literature.

Results

From 2001 to 2016, 103 consecutive brachial plexus tumors in 98 patients met inclusion criteria. Ninety percent of patients presented with a palpable mass, and 81% had deficits in sensation, motor function, or both. Mean follow-up time was 10 months. Serious complications were infrequent. For patients with a preoperative motor deficit, the rate of postoperative motor decline was 10%. For patients without a preoperative motor deficit, the rate of postoperative motor decline was 35%, which decreased to 27% at 6 months. There were no differences in motor outcome based on extent of resection, tumor pathology, or age.

Conclusion

We present one of the largest recent series of tumors of the brachial plexus region. Although the rate of worsened postoperative motor function was higher in those without preoperative weakness, the motor deficit improves over time and is no worse than antigravity strength in the majority of cases. Our findings help guide patient counseling in regard to postoperative motor function.

Patient demographics, tumor characteristics, and outcomes following surgical treatment of benign and malignant brachial plexus tumors: a systematic review

BACKGROUND

Various treatment options have been introduced for the management of primary tumors of the brachial plexus (BP), ranging from conservative therapy to wide local excision with/without postoperative chemoradiotherapy. However, no consensus exists regarding optimal treatment strategies based on collated and published data.

OBJECTIVE

The aim of this study was to investigate the clinicopathological characteristics and outcome of patients with primary tumors of the BP who underwent surgical treatment.

DATA SOURCES

A systematic search of the four main online databases, including Web of Science (WOS), PubMed, Scopus, and Google Scholar, was conducted.

STUDY SELECTION

All related articles addressing the clinical outcome and role of surgical interventions for management of primary tumors of the BP.

INTERVENTION

Optimal surgical and radiotherapeutic interventions for benign and malignant lesions based on the pathologic characteristics and location of primary BP tumors.

RESULTS

A total of 687 patients (693 tumors) with a mean age of 41.7±8.7 years old were evaluated. In total, 629 (90.8%) tumors were benign, and 64 (9.2%) were malignant, with a mean tumor size of 5.4±3.1 cm. The location of the tumor was reported for 639 patients. For these tumors, 444 (69.5%) originated from the supraclavicular region, and 195 (30.5%) were infraclavicular. The trunks were the most common location for tumor involvement, followed by the roots, cords, and terminal branches. Gross total resection was achieved in 432 patients and subtotal resection (STR) was performed in 109 patients. With neurofibromas, STR still resulted in good outcomes. The outcomes following treatment of malignant peripheral nerve sheath tumors were poor regardless of the type of resection. In general, symptoms related to pain and sensory issues resolved rapidly postoperatively. However, the resolution of motor deficits was often incomplete. Local tumor recurrence occurred in 15 (2.2%), patients and distant metastasis was observed in only eight (1.2%) cases. The overall mortality was 21 (3.1%) patients among the study population.

LIMITATIONS

The main limitation was the lack of level I and II evidence.

CONCLUSIONS

The ideal management strategy for primary BP tumors is complete surgical resection. However, in some cases, particularly for neurofibromas, STR may be preferable to preserve maximal neurological function. The degree of surgical excision (total or subtotal) mainly depends on the pathological characteristics and primary location of the tumor.

Ultrasound and MR imaging of peripheral nerve tumors: the state of the art

Peripheral nerve sheath tumors are a heterogeneous subgroup of soft tissue tumors that either arise from a peripheral nerve or show nerve sheath differentiation. On imaging, direct continuity with a neural structure or location along a typical nerve distribution represents the most important signs to suggest the diagnosis. Ultrasound and magnetic resonance imaging are the best modalities to evaluate these lesions. First, it is necessary to differentiate between a true tumor and a non-neoplastic nerve condition such as a neuroma, peripheral nerve ganglion, intraneural venous malformation, lipomatosis of nerve, or nerve focal hypertrophy. Then, with a combination of clinical features, conventional and advanced imaging appearances, it is usually possible to characterize neurogenic tumors confidently. This article reviews the features of benign and malignant peripheral nerve sheath tumors, including the rare and recently described tumor types. Furthermore, other malignant neoplasms of peripheral nerves as well as non-neoplastic conditions than can mimick neurogenic tumor are herein discussed.

Fibrolipomatous hamartoma of the median nerve: An unusual cause of carpal tunnel syndrome

Fibrolipomatous hamartoma is a rare benign tumor-like condition that affects most commonly the median nerve. The diagnosis is usually confirmed through its typical appearance on magnetic resonance imaging (MRI) without the need for a nerve biopsy. There are divergent views regarding treatment of this entity, but open carpal tunnel release for nerve decompression currently constitutes the standard care for alleviation of compressive neuropathy of the median nerve. In this report, we describe a case of fibrolipomatous hamartoma that was diagnosed via MRI and underwent open carpal tunnel release, with alleviation of the patient's symptoms.

Rationale and design of the peripheral nerve tumor registry: an observational cohort study

AIM

Peripheral nerve tumors (PNT) are rare lesions. To date, no systematic multicenter studies on epidemiology, clinical symptoms, treatment strategies and outcomes, genetic and histopathologic features, as well as imaging characteristics of PNT were published. The main goal of our PNT Registry is the systematic multicenter investigation to improve our understanding of PNT and to assist future interventional studies in establishing hypotheses, determining potential endpoints, and assessing treatment efficacy.

METHODS

Aims of the PNT registry were set at the 2015 Meeting of the Section of Peripheral Nerve Surgery of the German Society of Neurosurgery. A study protocol was developed by specialists in PNT care. A minimal data set on clinical status, treatment types and outcomes is reported by each participating center at initial contact with the patient and after 1 year, 2 years, and 5 years. Since the study is coordinated by the Charité Berlin, the PNR Registry was approved by the Charité ethics committee (EA4/058/17) and registered with the German Trials Registry (www.drks.de). On a national level, patient inclusion began in June 2016. The registry was rolled out across Europe at the 2019 meeting of the European Association of Neurosurgery in Dublin.

RESULTS

Patient recruitment has been initiated at 10 centers throughout Europe and 14 additional centers are currently applying for local ethics approval.

CONCLUSION

To date, the PNT registry has grown into an international study group with regular scientific and clinical exchange awaiting the first results of the retrospective study arm.

Melanoma metastasis to the femoral nerve: a novel case of melanoma masquerading as mononeuropathy. Illustrative case

BACKGROUND

Metastatic cancer may involve the central and peripheral nervous system, usually in the late stages of disease. At this point, most patients have been diagnosed and treated for widespread systemic disease. Rarely is the involvement of the peripheral nervous system the presenting manifestation of malignancy. One reason for this is a proposed "blood-nerve barrier" that renders the nerve sheath a relatively privileged site for metastases.

OBSERVATIONS

The authors presented a novel case of metastatic melanoma presenting as intractable leg pain and numbness. Further workup revealed concurrent disease in the brain and breast, prompting urgent treatment with radiation and targeted immunotherapy.

LESSONS

This case highlights the rare presentation of metastatic melanoma as a mononeuropathy. Although neurological complications of metastases tend to occur in later stages of disease after initial diagnosis and treatment, one must remember to consider malignancy in the initial differential diagnosis of mononeuropathy.

Neoplastic nerve lesions

Though metastasis and malignant infiltration of the peripheral nervous system is relatively rare, physicians should have a familiarity with their presentations to allow for prompt diagnosis and initiation of treatment. This article will review the clinical presentations, diagnostic evaluation, and treatment of neoplastic involvement of the cranial nerves, nerve roots, peripheral nerves, and muscle. Due to the proximity of the neural structure traversing the skull base, metastasis to this region results in distinctive syndromes, most often associated with breast, lung, and prostate cancer. Metastatic involvement of the nerve roots is uncommon, apart from leptomeningeal carcinomatosis and bony metastasis with resultant nerve root damage, and is characterized by significant pain, weakness, and numbness of an extremity. Neoplasms may metastasize or infiltrate the brachial and lumbosacral plexuses resulting in progressive and painful sensory and motor deficits. Differentiating neoplastic involvement from radiation-induced injury is of paramount importance as it dictates treatment and prognosis. Neurolymphomatosis, due to malignant lymphocytic infiltration of the cranial nerves, nerve roots, plexuses, and peripheral nerves, deserves special attention given its myriad presentations, often mimicking acquired demyelinating neuropathies.

Magnetic resonance imaging of the brachial plexus. Part 1: Anatomical considerations, magnetic resonance techniques, and non-traumatic lesions

For magnetic resonance imaging (MRI) of non-traumatic brachial plexus (BP) lesions, sequences with contrast injection should be considered in the differentiation between tumors, infection, postoperative conditions, and post-radiation changes. The most common non-traumatic inflammatory BP neuropathy is radiation neuropathy. T2-weighted images may help to distinguish neoplastic infiltration showing a high signal from radiation-induced neuropathy with fibrosis presenting a low signal.

MRI findings in inflammatory BP neuropathy are usually absent or discrete. Diffuse edema of the BP localized mainly in the supraclavicular part of BP, with side-to-side differences, and shoulder muscle denervation may be found on MRI.

BP infection is caused by direct infiltration from septic arthritis of the shoulder joint, spondylodiscitis, or lung empyema.

MRI may help to narrow down the list of differential diagnoses of tumors. The most common tumor of BP is metastasis. The most common primary tumor of BP is neurofibroma, which is visible as fusiform thickening of a nerve. In its solitary state, it may be challenging to differentiate from a schwannoma.

The most common MRI finding is a neurogenic variant of thoracic outlet syndrome with an asymmetry of signal and thickness of the BP with edema. In abduction, a loss of fat directly related to the BP may be seen.

Diffusion tensor imaging is a promising novel MRI sequences; however, the small diameter of the nerves contributing to the BP and susceptibility to artifacts may be challenging in obtaining sufficiently high-quality images.

•

MRI allows narrowing the list of differential diagnoses of brachial plexus lesions.

•

MRI helps to distinguish neoplastic infiltration from radiation neuropathy in T2-weighted images.

•

Differentiation between tumors, infection, postoperative conditions and post-radiation changes is possible with contrast.

•

MRI helps to determine the extent of the infection.

•

Diffusion tensor MRI is a promising method for brachial plexus assessment.

Neurophysiology during peripheral nerve surgery

Electrophysiological monitoring of the peripheral nervous system during a variety of surgeries provides useful information that supplements and complements preoperative assessment. Monitoring improves localization and understanding of the underlying pathophysiology of peripheral nerve lesions leading to more rational treatment decisions and improved outcomes. Monitoring is accomplished by adaptation of routine electrodiagnostic techniques (i.e., nerve conduction studies, evoked potentials, and electromyography) with special attention to technical factors including electrical and movement artifact. These techniques have been successfully applied during surgery for entrapment neuropathies, traumatic nerve injury and repair, peripheral nerve tumors, and adjacent structure procedures that risk peripheral nerve injury. A clear understanding of the anatomy and neurophysiology is necessary, as is understanding and performing the difficult technical aspects of these studies to provide accurate information to enhance patient outcome and recovery. As in any intraoperative neurophysiologic monitoring (IONM) setting, constant and accurate communication between the IONM team, surgeon, and anesthesia team is critically important to meet these goals.

An isolated cavernous malformation of the sixth cranial nerve: A case report and review of literature

Background

Isolated cavernous malformation (CM) of the abducens nerve has not been reported in the literature. Herein, the authors address the clinical importance of these lesions and review the reported cases of CM from 2014 to 2020.

Case Description

A 21-year-old man presented with binocular diplopia and headache from 2 months before his admission. The neurological examination revealed right-sided abducens nerve palsy. The brain MRI revealed an extra-axial pontomedullary lesion suggestive of a CM. The lesion was surgically removed. During the operation, the abducens nerve was resected considering the lesion could not be separated from the nerve and an anastomosis was performed using an interposition nerve graft and fibrin glue. Pathological examination of the resected lesion revealed that it was originated from within the nerve. The patient's condition improved in postoperative follow-ups.

Conclusion

Surgical resection of the cranial nerves CMs is appropriate when progressive neurological deficits are present. If the lesion is originated from within the nerve, we suggest resection of the involved nerve and performing anastomosis. Novel MRI sequences might help surgeons to be prepared for such cases and fibrin glue can serve as an appropriate tool to perform anastomosis when end-to-end sutures are impossible to perform.

Schwannoma in the extremity: clinical features and microscopic intra-capsular enucleation

Objective: Schwannomas are the most common type of neoplasm of the peripheral nerves. Enucleation is a standard surgical procedure; however, it occasionally results in iatrogenic nerve injury, even with atraumatic procedures. Herein, we present the clinical characteristics of schwannoma arising in the extremities and discuss the clinical outcomes of extra- and intra-capsular enucleation.

Patients and Methods: We reviewed 122 schwannomas treated at our institute. Schwannomas arising from the minor nerve (n=30) or intramuscularly (n=15) were operated using the extra-capsular technique. Of the 77 major nerve schwannomas, 62 schwannomas were treated using the intra-capsular technique and 15 schwannomas using the extra-capsular technique.

Results: Neurological deficits following enucleation were significantly lower using the intra-capsular technique than with the extra-capsular technique. The patient age, duration of symptoms, maximum tumor diameter, and site of occurrence were not associated with subsequent neurological deficits. With both techniques, no tumor recurrence was observed at the final follow-up.

Conclusion: These results support the use of intra-capsular micro-enucleation as a safe and reliable treatment for every type of schwannoma. To minimize the risk of nerve injury, en bloc resection should not be used because the main purpose of schwannoma surgery is the relief of symptoms, not tumor resection.

A rare case of chordoma presenting as a Pancoast tumor

The notochord is the defining structure of all chordate embryos. It is a midline structure ventral to the ectoderm, neural plates, and neural arch. Remnants of the notochord ultimately give rise to the nucleus pulposus. The function of the notochord is to organize the surrounding structures. Chordoma is a rare malignant bone tumor arising from remnants of the notochord. These tumors are indolent and can present as incidental or locally advanced involving adjacent structures. These tumors typically present at the skull base and sacral spine but more rarely can be seen on the cervical and thoracic spine. Rare cases of chordoma invading the brachial plexus have been recorded. Surgical resection is the mainstay of treatment for chordomas. We would like to discuss a novel presentation of a chordoma as a Pancoast tumor, and aim to highlight the clinical importance of accurate diagnosis and planning therapy along with poor prognosis of incomplete surgical resection.

A Bayesian approach for diagnostic accuracy of malignant peripheral nerve sheath tumors: a systematic review and meta-analysis

Background

Malignant peripheral nerve sheath tumors (MPNST) carry a dismal prognosis and require early detection and complete resection. However, MPNSTs are prone to sampling errors and biopsies or resections are cumbersome and possibly damaging in benign peripheral nerve sheath tumor (BPNST). This study aimed to systematically review and quantify the diagnostic accuracy of noninvasive tests for distinguishing MPNST from BPNST.

Methods

Studies on accuracy of MRI, FDG-PET (fluorodeoxyglucose positron emission tomography), and liquid biopsies were identified in PubMed and Embase from 2000 to 2019. Pooled accuracies were calculated using Bayesian bivariate meta-analyses. Individual level-patient data were analyzed for ideal maximum standardized uptake value (SUV_max) threshold on FDG-PET.

Results

Forty-three studies were selected for qualitative synthesis including data on 1875 patients and 2939 lesions. Thirty-five studies were included for meta-analyses. For MRI, the absence of target sign showed highest sensitivity (0.99, 95% CI: 0.94-1.00); ill-defined margins (0.94, 95% CI: 0.88-0.98); and perilesional edema (0.95, 95% CI: 0.83-1.00) showed highest specificity. For FDG-PET, SUV_max and tumor-to-liver ratio show similar accuracy; sensitivity 0.94, 95% CI: 0.91-0.97 and 0.93, 95% CI: 0.87-0.97, respectively, specificity 0.81, 95% CI: 0.76-0.87 and 0.79, 95% CI: 0.70-0.86, respectively. SUV_max ≥3.5 yielded the best accuracy with a sensitivity of 0.99 (95% CI: 0.93-1.00) and specificity of 0.75 (95% CI: 0.56-0.90).

Conclusions

Biopsies may be omitted in the presence of a target sign and the absence of ill-defined margins or perilesional edema. Because of diverse radiological characteristics of MPNST, biopsies may still commonly be required. In neurofibromatosis type 1, FDG-PET scans may further reduce biopsies. Ideal SUV_max threshold is ≥3.5.

[Granular cells tumour (Abrikossof) of the ulnar nerve at the arm. A case report and literature review]

INTRODUCTION

Granular cell tumours are extremely rare on peripheral nerves, with an incidence of 0.029% of pathologic samples. In a literature review, we found only 5 cases involving the ulnar nerve, although considered the most frequently involvement nerve.

CASE REPORT

A 32 year-old female from the French West Indies presented a severe arm pain with deficit of interosseous hand muscles. Imaging studies were in favour of a Schwanoma, but during surgery, we found an unremovable intra-neural tumour. Nerve biopsy revealed a granular cell tumour. Initial decision was observation only. However, within two years, tumour increased in size, along with pain aggravation and functional deficit. We performed a nerve resection (with adequate margins) with reconstruction using sural nerve graft associated with a neurotisation of the motor branch with the anterior interosseus nerve. At two years follow-up, no recurrence was observed. The scar is hypersensitive with moderate neuropathic pain. There is a sensory reinnervation of the fourth finger, with no motor recovery of the hand. We observed a slight recovery of flexor profundus tendons, which, in turn increased the claw hand.

DISCUSSION

The five cases described in the literature were managed differently (biopsy only, excision, excision with reconstruction), with modest results. There is no recommended treatment. Our case is the first at arm level. We were able to perform complete resection, but functional result is poor.

CONCLUSION

Granular cell tumours require treatment if symptomatic (pain, function loss), but, at the moment, there is no recommended treatment.

Fibrolipomatous Hamartoma of the Median Nerve: An Outcome of Surgical Management in Six Consecutive Cases

Background

Lipoma is a nonneurogenic benign tumor. Neurolipoma and fibrolipomatous hamartoma are variants of this universal tumor. All these variants are grouped under lipomatosis of the nerve. Majority of these tumors are asymptomatic, which can be observed. Symptomatic patients require surgery, which is not standardized. As there are insufficient number of cases, no randomized controlled studies have been performed in the treatment of fibrolipomatous hamartoma. The aim of our study was to determine the pattern of presentation of fibrolipomatous hamartoma, surgical management offered, and the outcome in the form of recovery and complications.

Materials and Methods

This retrospective descriptive study includes six patients diagnosed with fibrolipomatous hamartoma over a period of 12 years. Patient details were collected from the medical records. Patients diagnosed of fibrolipomatous hamartoma in the hand were included. Patients with other soft-tissue tumors were excluded from the study. Out of six patients, four required excision of nerve followed by reconstruction using sural nerve graft and two underwent microsurgical dissection of neural element. Patients were instructed to take care of the operated hand during the recovery phase. Institutional physiotherapy protocol was started during the 3^rd postoperative week. Follow-up period was between 1 and 3 years.

Results

All the six patients were free from symptoms postoperatively. Minimal complications were noted in two patients, which were managed conservatively.

Conclusion

Surgical excision of fibrolipomatous hamartoma of median nerve below elbow, with nerve dissection or with nerve reconstruction using sural nerve graft, followed by proper postoperative care and physiotherapy has proven beneficial for the patients in our study.

Selumetinib in the Treatment of Symptomatic Intractable Plexiform Neurofibromas in Neurofibromatosis Type 1: A Prospective Case Series with Emphasis on Side Effects

BACKGROUND

Plexiform neurofibromas (PN) are congenital tumors that affect up to 50% of individuals with neurofibromatosis type 1. Despite their benign nature, they can grow rapidly and cause severe morbidities. Selumetinib, an inhibitor of mitogen-activated protein kinase (MEK) 1 and 2, was reported to induce a clinical response in pediatric subjects with inoperable PN.

OBJECTIVE

The aim of this paper is to describe a prospective case series of patients treated with selumetinib with emphasis on drug adverse events.

PATIENTS AND METHODS

All the subjects who received selumetinib at the Pediatric Department of Scientific Research Institute and Hospital "Burlo Garofolo", from November 2017 to January 2020, were progressively included. We monitored the patients with a follow-up visit every 3 months. MRI or CT scans to monitor the growth of the tumor were performed after 3 months of treatment, and then every 6-9 months.

RESULTS

Selumetinib was prescribed to nine children, with a total of 17 inoperable PN. The mean follow-up period was 12 months. During the follow-up, one patient experienced an ischemic stroke, unrelated to the treatment. Only minor adverse events were observed: six individuals developed gastrointestinal side effects, seven patients presented a mild form of acne, six had paronychia, four developed irritability, and two showed a mild increase in creatine kinase. None of the patients stopped the treatment. Tumor reduction > 20% was recorded in 16 out of 17 PN (94%). One PN remained stable. No tumor growth was recorded during the treatment.

CONCLUSIONS

In this case series, selumetinib appears to be effective and safe for the pediatric population.

Diagnostic and management considerations in incidental common peroneal intraneural haemangioma

Intraneural haemangiomas are rare tumours that can affect peripheral nerves. We describe a case of a 10-year-old female with an incidental finding of a common peroneal nerve lesion following knee injury. MRI demonstrated avid heterogeneous enhancement and peri-lesional oedema, and an open biopsy was performed revealing haemangioma on histopathological analysis. The patient was managed with observation and remains intact at 24-month follow-up.

Posterior Tibial Nerve Schwannoma Presenting as Tarsal Tunnel Syndrome

Schwannomas are rare, benign tumors originating in the Schwann cells of the peripheral nervous system. They are most commonly found in the head, neck, and upper extremities, which involve the spinal nerves of the brachial plexus. However, schwannomas of the lower extremities are extremely uncommon, and few studies have reported a schwannoma originating from the posterior tibial nerve. We report on a case of a 71-year old male who presented to our clinic because of left foot and ankle neuritic pain. A nerve tumor was found; subsequently, the tumor was surgically excised along with the release of the tarsal tunnel.

Lipomas of the Brachial Plexus: A Case Series and Review of the Literature

BACKGROUND

Lipomas are common benign tumors. When they develop in proximity to peripheral nerves, they can cause neurologic symptoms secondary to mass effect. Previous reports have shown symptom resolution after removal of lipomas compressing various upper extremity peripheral nerves. However, brachial plexus lipomas are relatively rare. Our multidisciplinary experience with brachial plexus lipoma resection is reviewed in the largest case series to date.

METHODS

A retrospective chart review of all patients undergoing resection of brachial plexus lipomatous tumors between 2006 and 2016 was performed. Patient demographic data, diagnostic imaging, clinical presentation, operative details, surgical pathology, and clinical outcomes were reviewed.

RESULTS

Twelve brachial plexus lipomatous tumors were resected in 11 patients: 10 lipomas, 1 hibernoma, and 1 atypical lipomatous tumor. The most common tumor location was supraclavicular (50%), followed by axillary (42%), and proximal medial arm (8%). The most common brachial plexus segment involved was the upper trunk (50%), followed by posterior cord (25%), lateral pectoral nerve (8%), lower trunk (8%), and proximal median nerve (8%). Most patients presented with an enlarging painless mass (58%). Of the patients who presented with neurologic symptoms, symptoms resolved in the majority (80%).

CONCLUSIONS

Brachial plexus lipomas are rare causes of compression neuropathy in the upper extremity. Careful resection and knowledge of brachial plexus anatomy, which may be distorted by the tumor, are critical to achieving a successful surgical outcome with predictable symptom resolution. Finally, surveillance magnetic resonance imaging may be warranted for atypical lesions.

Intraneural lipomas: institutional and literature review

BACKGROUND

Adipose lesions of nerve can be envisioned as a spectrum ranging from intraneural/extraneural lipomas to lipomatosis of nerve (LN). We have noticed that intraneural lipomas are not as a homogenous group as previously thought and demonstrate differences which have clinical implications. To better understand intraneural lipomas, we conducted a search of cases at our institution and published cases in the world's literature.

MATERIALS AND METHODS

Mayo Clinic's database was searched between years 1994-2018. Published cases were identified using PubMed and Google Scholar databases. Following terms were used: intraneural lipoma, lipoma and nerve, lipoma and neuropathy, lipofibroma and nerve, fibrolipoma and nerve and neural lipoma as well as lipofibroma and fibrolipoma alone. Cases that could be clearly identified as intraneural lipomas by the location of the lipoma within the epineurium were included for analysis. These cases were then sub-classified as encapsulated intraneural lipomas or hybrid intraneural lipomas (demonstrating features of both intraneural/extraneural lipomas and LN) based on their characteristics.

RESULTS

We identified 12 cases at our institution (8 encapsulated, 4 hybrid) and 24 published cases (21 encapsulated, 3 hybrid). The most commonly affected nerve was median both at our institution and in the published cases. Encapsulated cases were found to be relatively easy to resect. Hybrid cases demonstrated variable degree of interdigitating fat between the fascicles and were relatively difficult to resect.

CONCLUSION

Intraneural lipomas exist as two separate entities with distinct clinical implications. Although rare, this should be taken in account when planning surgery. Terminology should be clarified to prevent ambiguity and confusion.

Saphenous nerve schwannoma as a cause of vascular claudication - case report and review of the literature

Schwannomas are peripheral nerve tumours that are uncommon. They typical present with a palpable mass, pain or neurological changes. We describe a saphenous nerve schwannoma compressing the superficial femoral artery and causing vascular claudication. We also review the literature.

Analysis According to Characteristics of 18 Cases of Brachial Plexus Tumors : A Review of Surgical Treatment Experience

Objective

Because the anatomical structure of the brachial plexus is very complex, surgical treatment of tumors in this region is challenging. Therefore, a lot of clinical and surgical experience is required for successful treatment; however, many neurosurgeons have difficulty accumulating this experience owing to the rarity of brachial plexus tumors. The purpose of this report is to share our surgical experience with brachial plexus tumor with other neurosurgeons.

Methods

The records of 18 consecutive patients with brachial plexus tumors who underwent surgical treatment between January 2010 and December 2017 in a single institution were retrospectively reviewed. The surgical approach was determined according to the tumor location and size, and intraoperative neurophysiological monitoring (IONM) was used in most of cases to prevent iatrogenic nerve injury during surgery. In addition, to evaluate the differences in tumor characteristics according to pathologic diagnosis, the tumors were divided twice into two groups, based on two separate classifications, and statistical analysis was performed.

Results

The 18 brachial plexus tumors comprised 15 (83.3%) benign peripheral nerve sheath tumors including schwannoma and neurofibroma, one (5.6%) malignant peripheral nerve sheath tumor, one (5.6%) benign tumor of non-neural sheath origin (neurogenic cyst), and one (5.6%) metastatic tumor (papillary carcinoma). The authors analyzed relationship between tumor size/location and tumor characteristic parameters such as age, size, right-left, and pathology. There were no statistically significant differences except a tendency of bigger tumor size in young age.

Conclusion

For a successful surgical outcome, an appropriate surgical approach is essential, and the appropriate surgical approach is determined by the location and size of the tumor. Furthermore, applying IONM may prevent postoperative complications and it is favorable option for brachial plexus tumors surgery.

Extraneuraxial Hemangioblastoma: Clinicopathologic Features and Review of the Literature

Extraneuraxial hemangioblastoma occurs in nervous paraneuraxial structures, somatic tissues, and visceral organs, as part of von Hippel-Lindau disease (VHLD) or in sporadic cases. The VHL gene plausibly plays a key role in the initiation and tumorigenesis of both central nervous system and extraneuraxial hemangioblastoma, therefore, the underlying molecular and genetic mechanisms of the tumor growth are initially reviewed. The clinical criteria for the diagnosis of VHLD are summarized, with emphasis on the distinction of sporadic hemangioblastoma from the form fruste of VHLD (eg, hemangioblastoma-only VHLD). The world literature on the topic of extraneuraxial hemangioblastomas has been comprehensively reviewed with ∼200 cases reported to date: up to 140 paraneuraxial, mostly of proximal spinal nerve roots, and 65 peripheral, 15 of soft tissue, 6 peripheral nerve, 5 bone, and 39 of internal viscera, including 26 renal and 13 nonrenal. A handful of possible yet uncertain cases from older literature are not included in this review. The clinicopathologic features of extraneuraxial hemangioblastoma are selectively presented by anatomic site of origin, and the differential diagnosis is emphasized in these subsets. Reference is made also to 10 of the authors' personal cases of extraneuraxial hemangioblastomas, which include 4 paraneuraxial and 6 peripheral (2 soft tissue hemangioblastoma and 4 renal).

Plexus and peripheral nerve metastasis

Cancer in the form of solid tumors, leukemia, and lymphoma can infiltrate and metastasize to the peripheral nervous system, including the cranial nerves, nerve roots, cervical, brachial and lumbosacral plexuses, and, rarely, the peripheral nerves. This review discusses the presentation, diagnostic evaluation, and treatment options for metastatic lesions to these components of the peripheral nervous system and is organized based on the anatomic distribution. As skull base metastases (also discussed in Chapter 14) result in cranial neuropathies, these will be covered in detail, as well as cancers that directly infiltrate the cranial nerves. Particular emphasis is placed on the clinical, imaging, and electrodiagnostic features that differentiate neoplastic plexopathies from radiation-induced plexopathies. Neurolymphomatosis, in which malignant lymphocytes invade the cranial nerves, nerve roots, brachial and lumbosacral plexuses, and peripheral nerves, is a rare manifestation of lymphoma and leukemia. Diagnoses of neurolymphomatosis are often missed or delayed given its varied presentations, resulting in poorer outcomes. Thus this disease will also be discussed in depth.

Mixed Lymphangioma and Cavernous Hemangioma Within the Ulnar Nerve: A Case Report

BACKGROUND

Lymphangiomas are benign lymphatic vessel hamartomas typically found in the skin or subcutaneous tissue of the head and neck. Although mostly seen in a congenital context, acquired forms have been reported. By contrast, cavernous hemangiomas are benign hamartomas of endothelial origin. They can arise anywhere in the body, but are typically described as arising from the central nervous system.

METHODS

We report the case of a young patient who developed a mixed lymphangioma and cavernous hemangioma within the ulnar nerve. The tumor was removed during an intrafascicular dissection with preservation of all major fascicles.

RESULTS

Postoperatively, the patient retained intrinsic motor function and full sensation returned. This is the first published case of this type of mixed tumor occurring in a peripheral nerve.

CONCLUSIONS

It could not be ascertained whether trauma was the mechanism by which a lymphangioma developed within the peripheral nerve, as has been proposed. Although this is plausible, alternative mechanisms should be considered.

Median Nerve Cavernous Hemangioma

Hemangiomas of the median nerve are extremely rare; only 12 cases have been reported in the literature. We discuss a patient who presented with paresthesia and pain along the distribution of the left median nerve secondary to a cavernoma of the proximal part of the nerve as suspected on MRI scan. Total removal of the mass was achieved with immediate relief of the symptoms and no neurologic deficit. We conclude that despite being quite rare, the diagnosis of occult vascular lesions of peripheral nerves such as the median nerve, should be considered, especially when other common pathologies are excluded.

Benign tumors affecting the median nerve. Case series report of diagnostic and surgical strategies

Objective

The aim of this study was to describe the strategies adopted in this institution to diagnose and treat patients with benign tumors affecting the median nerve.

Methods

A retrospective chart review study of all patients operated on between 2010 and 2015. Histology, symptoms, complementary exams, surgical techniques performed, and demographic characteristics were analyzed.

Results

Fifty-four patients were included in the study. There were three neurofibromas, six schwannomas, 15 lipofibromatous hamartomas, three hemangiomas, 12 lipomas, one benign fibrohistiocytoma, and 14 synovial cysts. Complete tumoral resection was performed in 32 cases, partial resection in five, segmented nerve resection in one, nerve decompression in eight, and amputation for macrodactyly in eight.

Conclusions

The most important recommendations on treating benign tumors of the median nerve are related to the clinical symptoms, tumoral growth, and tumoral nature. The surgical approach resulted in good function for 60% of the patients. However, lipofibromatous hamartomas, hemangiomas, and neurofibromas were associated with preoperative functional deficit. It may be inferred that the diagnosis and treatment of these tumors should be performed earlier.

Tumors of the peripheral nervous system: analysis of prognostic factors in a series with long-term follow-up and review of the literature

OBJECT

Only a few published studies of the surgical treatment of benign peripheral nerve sheath tumors (BPNSTs), malignant peripheral nerve sheath tumors (MPNSTs), and peripheral non–neural sheath tumors (PNNSTs) have analyzed the results and possible prognostic factors using multivariate analysis. The authors report on their surgical series of cases of BPNSTs, MPNSTs, and PNNSTs with long-term follow-up and analyze the role of selected factors with respect to the prognosis and risk of recurrence of these tumors using multivariate analysis. They also review the pertinent literature and discuss their results in its context.

METHODS

The authors retrospectively reviewed data from cases involving patients who underwent resection of a peripheral nerve tumor between January 1983 and December 2013 at their institution. Of a total of 200 patients, 150 patients (with 173 surgically treated tumors) had adequate follow-up data available for analysis. Pain was assessed using a visual analog scale (VAS), and motor and sensory function were assessed by means of the Louisiana State University grading system. They also analyzed the relationship between tumor recurrence and patient sex, patient age, diagnosis of neurofibromatosis (NF), tumor histopathology, tumor size, tumor location, and extent of resection (subtotal vs gross-total resection), using univariate and multivariate analyses.

RESULTS

There was a statistically significant improvement in the mean VAS pain score (preoperative 3.96 ± 2.41 vs postoperative 0.95 ± 1.6, p = 0.0001). Motor strength and sensory function were significantly improved after resection of tumors involving the brachial plexus (p = 0.0457 and p = 0.0043, respectively), tumors involving the upper limb (p = 0.0016 and p = 0.0016, respectively), BPNSTs (p = 0.0011 and p < 0.0001, respectively), and tumors with dimensions less than 5 cm (motor strength: p = 0.0187 and p = 0.0021 for ≤ 3 cm and 3–5 cm tumors, respectively; sensory function: p = 0.0003 and p = 0.0001 for ≤ 3 cm and 3–5 cm tumors, respectively). Sensory function showed a statistically significant improvement also in patients who had undergone resection of tumors involving the lower limb (p = 0.0118). Total resection was associated with statistically significant improvement of motor strength (p = 0.0251) and sensory function (p < 0.0001). In univariate analysis, a history of NF (p = 0.0034), a diagnosis of MPNST or PNNST (p < 0.0001), and subtotal resection (p = 0.0042) were associated with higher risk of tumor recurrence. In multivariate analysis (logistic regression analysis), a history of NF (OR 9.28%, 95% CI 1.62–52.94, p = 0.0121) and a diagnosis of MPNST (OR 0.03%, 95% CI 0.002–0.429, p = 0.0098) or PNNST (OR 0.081%, 95% CI 0.013–0.509, p = 0.0077) emerged as independent prognostic factors for tumor recurrence.

CONCLUSIONS

A total resection should be attempted in all cases of peripheral nervous system tumors (irrespective of the supposed diagnosis and tumor dimensions) because it is associated with better prognosis in term of functional outcome and overall survival. Moreover, a total resection predicts a lower risk of tumor recurrence. Patients with a history of NF and tumors with malignant histology remain a challenge both for neurosurgeons and oncologists due to higher recurrence rates and the lack of standardized adjuvant therapies.

Primary Brachial Plexus Tumors: Clinical Experiences of 143 Cases

OBJECTIVE

Primary brachial plexus tumors are extremely rare and the treatment is challengeable. Our aim is to share the experiences in the treatment of primary brachial plexus tumors.

METHODS

A retrospective analysis of 143 patients with primary brachial plexus tumors was made in our department from January 2001 to December 2012. The clinical presentation of the patients, the characteristics and pathological results of the tumors and the prognosis were described.

RESULTS

Seventy-eight males and sixty-five female were enrolled. The mean age was 48.17 years old. A palpable mass was the most common clinical presentation occurred in 129 patients. The trunks of the brachial plexus were the locations where the tumors originated with high possibility, with 68 cases. Benign tumors were composed of 119 schwannomas and 12 neurofibromas, while malignant tumors were composed of 8 malignant peripheral nerve sheath tumors, 2 malignant granular cell tumors, 1 synovial sarcoma and 1 peripheral primitive neuroectodermal tumor. Appropriate surgical method, radiotherapy and chemotherapy were used according to the condition during operation, preoperative examinations and pathological result. The survival rate was 50.00% with a 3-year follow-up. Local recurrence happened in 7 patients. Five patients presented Metastasis.

CONCLUSIONS

Appropriate surgical method is the key for the treatment of different brachial plexus tumors. Surgery has a great effect on the treatment of benign tumors. For malignant tumors, adjuvant radiotherapy or chemotherapy should be used according to the pathological result. The general prognosis for malignant brachial plexus tumors is less than ideal.

Annual review of children with neurofibromatosis type 1

We aim to provide a concise, evidence-based framework to assist secondary level, community and acute paediatricians during a 20-60 min annual review of children with neurofibromatosis type 1. This review does not cover all aspects of the disorder. We recognise the importance of an overview of the pathogenesis, molecular genetic testing, clinical manifestations and management; we shall cover some of this briefly, but this is not our focus here. We focus instead on the following areas: (A) what questions should be asked during annual review, (B) what should be included in a focused examination, (C) when to request further investigations and (D) when should a referral be made to tertiary specialists and other members of the multidisciplinary team. Ongoing debates regarding screening remain in certain areas, particularly regarding imaging and ophthalmology follow-up; here we summarise the differing opinions and make a recommendation based on the currently available evidence.

High resolution neurography of the brachial plexus by 3 Tesla magnetic resonance imaging

The study of the structures that make up the brachial plexus has benefited particularly from the high resolution images provided by 3T magnetic resonance scanners. The brachial plexus can have mononeuropathies or polyneuropathies. The mononeuropathies include traumatic injuries and trapping, such as occurs in thoracic outlet syndrome due to cervical ribs, prominent transverse apophyses, or tumors. The polyneuropathies include inflammatory processes, in particular chronic inflammatory demyelinating polyneuropathy, Parsonage-Turner syndrome, granulomatous diseases, and radiation neuropathy. Vascular processes affecting the brachial plexus include diabetic polyneuropathy and the vasculitides. This article reviews the anatomy of the brachial plexus and describes the technique for magnetic resonance neurography and the most common pathologic conditions that can affect the brachial plexus.

Peripheral nerve lipoma: Case report of an intraneural lipoma of the median nerve and literature review

Adipose lesions rarely affect the peripheral nerves. This can occur in two different ways: Direct compression by an extraneural lipoma, or by a lipoma originated from the adipose cells located inside the nerve. Since its first description, many terms have been used in the literature to mention intraneural lipomatous lesions. In this article, the authors report a case of a 62-year-old female who presented with an intraneural median nerve lipoma and review the literature concerning the classification of adipose lesions of the nerve, radiological diagnosis and treatment.

Desmoid tumors in neurosurgery: a review of the literature

Desmoid tumors (DTs) are rare myofibroblastic neoplasms, which are mostly sporadic, but sometimes associated with familial adenomatous polyposis syndrome. Neurosurgical cases of DT have been very scarce. We review the literature concerning neurosurgical DTs and describe the first case of a cicatricial DT after the resection of vestibular schwannoma, presenting as a painful swelling in the retrosigmoid scar. Contrary to other localizations in the body, standard-of-care wide margin resection cannot be performed in intracranial and spinal DTs. Therefore, maximally safe resection followed by radiotherapy when tumor margins are not free can be proposed as a treatment strategy in neurosurgical DTs.