[Interdisciplinary Treatment Of Tumorous And Tumour-Like Lesions Of Peripheral Nerves]. / Interdisziplinäre Behandlung von Raumforderungen in Assoziation zu peripheren Nerven: Tumore und tumorähnliche Läsionen.

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".

Differentiation of Peripheral Nerve Tumors in the Brachial Plexus.

Schwannomas are benign extracranial nerve sheath tumors that can rarely affect the brachial plexus. Due to the relative rarity of these tumors and the complexity of the anatomy of the neck and shoulder, these tumors are a challenging diagnosis for clinicians. We present a case report of a 51-year-old male with a brachial plexus schwannoma definitively treated with surgical resection. It is our hope that this case serves as a reminder to consider schwannomas in the differential diagnosis for infraclavicular tumors.

Myofibroma mimicking peripheral nerve sheath tumour with ulnar nerve compression symptoms.

We report a case of myofibroma encasing the ulnar nerve on the medial aspect of the left arm with motor and sensory deficit secondary to compression. Initially, the tumour appeared to be a benign peripheral nerve sheath tumour based on preoperative imaging, with clinical examination positive for left hand clawing and a positive Wartenberg's and Froment's sign. However, intraoperative dissection demonstrated that the mass did not originate from the ulnar nerve proper, lowering suspicion for a peripheral nerve sheath tumour. Histopathological analysis showed spindle cell neoplasm, consistent with myofibroma. The patient underwent hand occupational therapy subsequently, with improvement of grip strength from 5 lb to 12 lb by 4 months postoperatively and resolution of clawing of the hand postoperatively. We discuss differentiating features for this rare occurrence of solitary adult myofibroma, where the final diagnosis was only made after formal histopathological analysis.

Monophasic synovial sarcoma mimicking schwannoma: a case report of a rare peripheral nerve tumor and literature review.

INTRODUCTION: Synovial sarcomas occurring as primary nerve tumors (SSPN) are rare and only 69 cases of SSPNs are reported in literature. Despite the little data available, SSPNs differ from other SSs in some distinctive aspects such as epidemiology, location, and early onset of symptoms. SSPN are consequently underdiagnosed and easily mistaken for benign or malignant peripheral nerve sheath tumors (PNST). Therefore, cytogenetic or molecular testing becomes essential in order to make a correct diagnosis. This article deals with an extremely rare case of monophasic SSPN of the posterior cords of the right brachial plexus. To our knowledge, this is only the tenth case of intraneural synovial sarcoma involving the brachial plexus. CASE PRESENTATION: We report the case of a 64-year-old man, who came to our attention due to a slow-growing painful right axillary neoformation, approximately 25 mm in size. The patient did not show any neurological impairments. Ultrasonography and constrast MRI showed a heterogeneous mass arising from the posterior cord of the right brachial plexus, resembling a schwannoma. The patient underwent total resection of tumor and capsule. Histologically, a diagnosis of monophasic synovial sarcoma was made based on histologic features and the immunohistochemical profile. CONCLUSIONS: We report a rare primary synovial sarcoma of the brachial plexus. Given its rarity, the diagnosis may be challenging and requires a core biopsy or the surgical specimen to permit immune-molecular analysis. Margin-free surgery is the mainstay of curative treatment, while chemo- or radiotherapy may have a role in advanced or margin-positive neoplasms.

Benign Neurogenic Tumors.

Neurogenic tumors arise from cells of the nervous system. These tumors can be found anywhere along the distribution of the sympathetic and parasympathetic nervous system and are categorized based on cell of origin: ganglion cell, paraganglion cell, and nerve sheath cells. Ganglion cell-derived tumors include neuroblastomas, ganglioneuroblastomas, and ganglioneuromas. Paraganglion cell-derived tumors include paragangliomas and pheochromocytomas. Nerve sheath cell-derived tumors include schwannomas (neurilemmomas), neurofibromas, and neurofibromatosis. Most of these are benign; however, they can cause local compressive symptoms. Surgery is the mainstay of treatment, if clinically indicated. Nonetheless, a thorough preoperative workup is essential, especially for catecholamine-secreting tumors.

Tumor de nervio periférico: una localización poco habitual / Peripheral nerve tumor: an unusual location

Benign tumors of peripheral nerves called Schwannomas or neurilemomas, correspond to a rare pathology, represent 5% of all tumors of the upper extremity, and affects, mainly, the ulnar nerve. The incidence of Schwannoma in the literature for the radial nerve is not clearly established given the infrequency of its presentation, there are only reports of isolated cases The following publication presents the case of a male patient with a radial nerve schwannoma. Clinically, presents increased painful volume on palpation, well delimited, of soft consistency in the distal third of the right arm of 3 years of evolution, without history of previous trauma, without irradiation, or paresthesia, with preservation of motor and sensory function of radial, median and ulnar nerve. Considering that the involvement of the radial nerve is very low frequency, a review is carried out in PubMed, in the last 10 years, there are only 9 studies, grouped in case reports and imaging studies for diagnosis.

Paraganglioma of the cauda equina: A clinicopathologic study of 12 cases with demonstration of cytokeratin positivity.

Paragangliomas are rare neuroendocrine tumors originating from neural crest-derived paraganglion cells. Primary cauda equina paraganglioma (CEP) pose both diagnostic and surgical challenges. We report 12 cases of CEP to characterize the diagnostic and operative approach to these rare tumors. 12 cases with primary CEP were studied; 5 patients were male (41.7%) and 7 were female (56.3%). The median age was 44 years (range: 15-64 years). The most common symptom was lower back pain of variable duration. Radiologically, the lesions were intradural and extramedullary with well-defined margins, and ranged from 1 to 4.5 cm. in diameter (mean: 1.65 cm). 9 tumors were composed of sheets and nests of cells with a neuroendocrine pattern and intense vascularity and displayed a characteristic Zellballen pattern. Interestingly, CAM 5.2 was diffusely or focally positive with a dot-like or membrane pattern in 8/11 cases (72.7%). Similarly, CK was diffusely or focally positive with membrane and cytoplasmic staining or with a dot-like pattern in 7/11 (63.6%) and 2/11 cases (18.2%). None of the cases showed deletion of SDHB nor expression of GATA3. CEP can display aberrant keratin positivity, and this should be considered in the differential diagnosis of these lesions. This finding also raises the possibility that CEP may be an entirely different entity than non-spinal paragangliomas.

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.

Paraganglioma of the cauda equina: a tertiary centre experience and scoping review of the current literature.

Cauda equina paragangliomas are rare benign extra-adrenal neuroendocrine tumours arising from the neural crest cells associated with autonomic ganglia. These tumours are often mistaken preoperatively for ependymomas or schwannomas. Patients present with axial or radicular pain with or without neurological deficits. Recurrence, secretory features and length of follow-up are controversial. We conducted a retrospective cohort study of paraganglioma through searching a prospectively maintained histopathology database. Patient demographics, presentation, surgery, complications, recurrence, follow-up and outcome between 2004 and 2016 were studied. The primary aim was to collate and describe the current evidence base for recurrence and secretory features of the tumour. The secondary objective was to report outcome and follow-up strategy. A scoping review was performed in accordance with the PRISMA-ScR Checklist. Ten patients were diagnosed (M:F 7:3) with a mean age of 53.6 ± 5.1 (range 34-71 years). MRI scans revealed intradural lumbar enhancing lesions. All patients had complete microsurgical excisions without adjuvant therapy with no recurrence with a mean follow-up of 5.1 ± 1.4 years. Tumours were attached to the filum terminale. Electron microscopic images demonstrated abundant neurosecretory granules with no evidence of catecholamine production. A total of 620 articles were screened and 65 papers (including ours) combining 121 patients (mean age 48.8 and M:F 71:50) were included. The mean follow-up was 3.48 ± 0.46 (range 0.15-23 years). Back pain was the most common symptom (94%). Cure following surgery was achieved in 93% of the patients whilst 7% had recurrence. Total resection likely results in cure without the need for adjuvant therapy or prolonged follow-up. However, in certain situations, the length of follow-up should be determined by the treating surgeon.

Hiperqueratosis plantar / Plantar hyperkeratosis

RESUMEN La hiperqueratosis es un trastorno caracterizado por el engrosamiento de la capa externa de la piel, que está compuesta de queratina, una fuerte proteína protectora. Puede ser causada por fricción, conllevando la aparición de callosidades, inflamación crónica, eccema o trastornos genéticos, como la ictiosis ligada al cromosoma X. Se presentó el caso de un paciente de 47 años, que acudió al Servicio de Ortopedia por lesión escamosa a nivel de ambas regiones plantares con dificultad para la marcha. El tratamiento quirúrgico fue el empleado en este paciente para la obtención de la biopsia exerética. La evolución fue favorable en el postoperatorio mediato e inmediato, y el paciente se incorporó de forma rápida a su vida normal. Con este caso se identificaron las características clínicas de la hiperqueratosis plantar, así como el uso de la biopsia exerética como estándar de oro para el diagnóstico positivo en los tumores periféricos. Un diagnóstico adecuado por el médico inicial, la interrelación del Servicio de Ortopedia con la consulta de tumores periféricos, y el tratamiento quirúrgico seleccionado, constituyen factores determinantes en la evolución favorable de los pacientes con este diagnóstico (AU).

ABSTRACT Hyperkeratosis is a disorder characterized by thickening of the outer layer of the skin, which is composed of keratin, a strong protective protein. It can be caused by friction, leading to callosities, chronic inflammation, eczema or genetic disorders such as X chromosome-linked ichthyosis. We presented the case of a patient, aged 47 years, who attended the Orthopedic Service for scaly lesion at the level of both plantar regions with difficulties to walk. Surgical treatment was used in this patient to obtain an exeretic biopsy. The evolution was favorable in both the mediate and immediate postoperative period, and the patient quickly returned to his normal life. This case identified the clinical characteristics of plantar hyperkeratosis and the use of exeretic biopsy as a gold standard for positive diagnosis in the peripheral tumors. An adequate diagnosis by the initial physician, the interrelation of the orthopedic service with the consultation of peripheral tumors, and the chosen surgical treatment are determining factors in the favorable evolution of patients with this diagnosis (AU).

Intradural extramedullary capillary hemangioma of the cauda equina: case report of a rare spinal tumor.

INTRODUCTION: Intradural extramedullary capillary hemangiomas of the cauda equina are exceedingly rare, with only 20 previous cases reported. In the adult population, these tumors are rare and can arise in the central and peripheral nervous systems from the dura or spinal nerve roots. Intradural capillary hemangiomas of the cauda equina can yield symptoms such as lower extremity weakness, pain, and bladder and bowel dysfunction. The clinical symptomology and surgical management of this rare spinal lesion are reviewed in this case report. CASE PRESENTATION: A 50-year-old male presented with progressive bilateral lower extremity weakness for 2 years, with recent bladder and bowel dysfunction. On physical exam, strength was symmetrically impaired in both lower extremities. Pre-operative magnetic resonance imaging (MRI) of the lumbar spine demonstrated a gadolinium-enhanced intradural lesion at the L4 level. Laminectomy was performed and the lesion was resected. Histopathological analysis determined that the tumor demonstrated features consistent with a capillary hemangioma. DISCUSSION: Clinically, patients with capillary hemangiomas of the cauda equina present with space-occupying compressive deficits, including progressive low back and lower extremity pain, motor deficits, paresthesias, sensory loss, and bowel and bladder dysfunction. Acute presentation can transpire following a hemorrhagic episode, although this is more associated with cavernous rather than capillary hemangiomas. Our patient demonstrated non-acute, progressive weakness, and late-onset bladder and bowel dysfunction. This report demonstrates that this rare lesion should be included in the differential diagnosis of cauda equina lesions.

When "Peripheral" Becomes "Central": Primary and Secondary Malignant Intracerebral Nerve Sheath Tumor: A Case Report and a Systematic Review.

BACKGROUND: The intracerebral occurrence of malignant peripheral nerve sheath tumors (MPNSTs) is exceedingly rare, and despite aggressive treatments, local recurrence and poor prognosis are very frequent. Like other brain tumors, these tumors could be primary or secondary, making the term "peripheral" an imprecise term for a primary brain tumor. OBJECTIVE: To analyze the reported cases of primary and secondary cerebral MPSNTs in terms of diagnosis, treatment, and overall survival. Additionally, we present a case of malignant intracerebral nerve sheath tumor (MINST) treated with radical surgery and radiotherapy. METHODS: Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, one database (PubMed) and crossed references were queried for MPNST with brain metastasis and primary MINSTs from 1971 to 2020. Data regarding demographic features, primary tumor site, risk factors, brain location of the lesion, treatment applied, and overall survival were extracted. RESULTS: A total of 55 patients were selected (including the reported case): 29 patients were secondary brain MPNST and 26 patients were primary MINST. The mean age was 41.8 ± 22 and 31.2 ± 23 yr, respectively. All brain metastases of MPNST (100%) had a primary tumor elsewhere in the body at the time of diagnosis. The overall survival was significantly shorter in patients with a secondary brain MPNST compared to MINST (P = .002). CONCLUSION: We present a comprehensive analysis of every reported primary and secondary intracerebral MPNST. The prognosis in terms of survival is worst in the last one despite aggressive treatment. The lack of a primary MPNST in screening tests is sufficient to confirm a MINST at time of diagnosis.

Lymphomatosis cerebri with cauda equina lymphoma.

PURPOSE/AIM: Lymphomatosis cerebri (LC) and cauda equina lymphoma are both rare forms of primary central nervous system lymphoma (PCNSL). LC is characterized by diffuse bilateral non-enhancing (or partially enhancing) inltrative lesions without mass effect, which can be easily confused with other forms of leukoencephalopathy and, thus, lead to delays in diagnosis. CASE REPORT: For the first time, a case of LC concomitant with cauda equina involvement confirmed by brain stereotactic biopsy is presented. CONCLUSIONS: This case highlights the necessity of using a multimodal strategy in diagnosing PCNSL, including multimodal magnetic resonance, cerebral spinal fluid cytology, flow cytometry and fluorodeoxyglucose positron emission tomography/computed tomography.

Peripheral nerve sheath tumor: differentiation of malignant from benign tumors with conventional and diffusion-weighted MRI.

OBJECTIVES: To evaluate potential of conventional MRI and diffusion-weighted imaging (DWI) for differentiating malignant from benign peripheral nerve sheath tumors (PNSTs). METHODS: Eighty-seven cases of malignant or benign PNSTs in the trunk or extremities that underwent conventional MRI with contrast enhancement, DWI, and pathologic confirmation between Sep. 2014 and Dec. 2017 were identified. Of these, 55 tumors of uncertain nature on MRI were included. Tumor size, signal, and morphology were reviewed on conventional MRI, and apparent diffusion coefficient (ADC) values of solid enhancing portions were measured from DWI. Patient demographics, MRI features, and ADC values were compared between benign and malignant tumors, and robust imaging findings for malignant peripheral nerve sheath tumors (MPNSTs) were identified using multivariable models. RESULTS: A total of 55 uncertain tumors consisted of 18 malignant and 37 benign PNSTs. On MRI, tumor size, margin, perilesional edema, and presence of split fat, fascicular, and target signs were significantly different between groups (p < 0.05), as were mean and minimum ADC values (p = 0.002, p < 0.0001). Most inter-reader agreement was moderate to excellent (κ value, 0.45-1.0). The mean ADC value and absence of a split fat sign were identified as being associated with MPNSTs (odds ratios = 13.19 and 25.67 for reader 1; 49.05 and 117.91 for reader 2, respectively). The C-indices obtained by combining these two findings were 0.90 and 0.95, respectively. CONCLUSIONS: Benign and malignant PNSTs showed different features on MRI and DWI. A combination of mean ADC value and absence of split fat was excellent for discriminating malignant from benign PNSTs. KEY POINTS: • It is important to distinguish between malignant peripheral nerve sheath tumors (MPNSTs) and benign peripheral nerve sheath tumors (BPNSTs) to ensure an appropriate treatment plan. • On conventional MRI and diffusion-weighted imaging (DWI), MPNSTs and BPNSTs showed significant differences in tumor size, margin, presence of perilesional edema, and absence of split fat, fascicular, and target signs. • Absence of a split fat sign and mean apparent diffusion coefficient (ADC) values were robust imaging findings distinguishing MPNSTs from BPNSTs, with a C-index of > 0.9.

Sural nerve schwannoma: A case report.

A 54-year old female with lateral ankle and foot pain was referred to an orthopaedic specialist clinic. Examination and investigations revealed a painful mass surrounding the sural nerve. Surgical excision confirmed the diagnosis of a sural nerve schwannoma. The following case report discusses this patient's presentation in further depth, as well as information about schwannomas, their frequency in the lower limb, and recommendations for investigation and management. LEVEL OF CLINICAL EVIDENCE: 6.

Solitary popliteal neurofibroma: an unusual encounter.

Diagnosing a popliteal fossa mass can be intriguing at times, and are not always Baker's cysts, as expected. We present an uncommon case of a young lady who presented with a palpable firm mass in the popliteal fossa with no neurological deficit or compromised distal pulsations. On surgical exploration, it was found to be a well defined, firm mass, closely abutting the neurovascular bundle, which on histopathological study revealed a solitary encapsulated neurofibroma.

Retrospective Analysis of 20 Patients Affected by Schwannomas in the Upper and Lower Limbs / Análise retrospectiva de 20 pacientes acometidos por schwannoma nos membros superior e inferior

Abstract Objective To analyze the epidemiological profile and evolution of 20 patients diagnosed with upper- and lower-limb schwannomas. Methods A group of patients was defined for a retrospective evaluation comprising the period between February 2002 and June 2018, in which we studied and evaluated 20 medical records of patients undergoing surgery due to schwannoma; the diagnosis was confirmed by an anatomopathological examination. Results Male and female patients were equally affected. The average age was 50.85 years, ranging from 12 to 77 years. There was a predominance of the upper limb and of the flexor face. The most affected nerve was the ulnar nerve. In total, 6 (30%) patients had transient postoperative complications. No cases of tumor recurrence were identified. Conclusion Schwannoma is a rare and difficult-to-diagnose lesion. It should always be considered as a hypothesis when facing a soft-tissue tumor affecting the limbs. The Tinel sign should be regarded, given its higher correlation with complications. The patients should be informed of the possible postoperative complications, which are frequent but usually transient.

Resumo Objetivo Analisar o perfil epidemiológico e a evolução de 20 pacientes diagnosticados com schwannoma nos membros superiores e inferiores. Métodos Definiu-se um grupo de pacientes para avaliação retrospectiva, compreendendo o período entre fevereiro de 2002 e junho de 2018, no qual foram estudados e avaliados 20 prontuários de pacientes submetidos a procedimento cirúrgico devido a schwannoma; a confirmação diagnóstica foi feita pelo exame anatomopatológico. Resultados Tanto os pacientes do sexo masculino quanto do feminino foram igualmente acometidos, e a média de idade foi de 50,85 anos, variando de 12 a 77 anos. Houve predomínio do membro superior e da face flexora. O nervo mais acometido foi o ulnar, e 6 (30%) pacientes apresentaram complicações pós-operatórias transitórias. Não foi identificado nenhum caso de recidiva tumoral. Conclusão O schwannoma é uma lesão rara e de difícil diagnóstico. Deve sempre ser considerada como hipótese quando se estiver diante de um tumor de partes moles acometendo os membros. O sinal de Tinel deve ser levado em consideração por conta de sua maior correlação com as complicações. Os pacientes devem ser informados quanto às possíveis complicações pós-operatórias, que são frequentes, mas, geralmente, transitórias.