A Rare Case of a Schwannoma on the Foot - Case Report / Caso raro de um schwannoma no pé - Relato de caso

Abstract A Schwannoma is an infrequent lesion. This tumor derives from the myelin sheath of the peripheral nerves; in most cases, it is benign and rarely presents in the foot and ankle region. Patients affected by this type of pathology are usually asymptomatic. Still, they sometimes have sensory or motor neurologic symptoms if the tumor is large enough to cause direct or indirect compression of the affected nerve. A 55-year-old male patient presented to our department with non-traumatic swelling and pain in the lateral aspect of the right foot and leg. A magnetic resonance imaging (MRI) scan of the right leg revealed a well-circumscribed lesion, measuring 2,5 by 1 cm, showing hypointensity on T1 sequences and hyperintensity on T2, compatible with a superficial peroneal nerve sheath cells tumor. Surgical excision of the lesion was performed, and the histopathological examination confirmed the initial suspicion—Schwannoma of the superficial peroneal nerve. The postoperative period was uneventful, with progressive improvement of pain and complete functional recovery without neurological deficits. Rigorous clinical examination associated to MRI scans allow adequate diagnosis as well as the exclusion of other pathologies with similar clinical presentation. Thus, the surgeon has to be aware of all the data for an effective diagnosis and treatment in this type of rare pathology that cannot be neglected.

Resumo Um schwannoma é uma lesão pouco frequente, sendo um tumor que deriva da bainha de mielina dos nervos periféricos; na maioria dos casos, este tumor é benigno e raramente se apresenta na região do pé e tornozelo. Os pacientes afetados por esse tipo de patologia são geralmente assintomáticos. Ainda assim, às vezes eles têm sintomas neurológicos sensoriais ou motores se o tumor for grande o suficiente para causar a compressão direta ou indireta do nervo afetado. Um paciente do gênero masculino de 55 anos se apresentou ao nosso departamento com inchaço não traumático e dor no aspecto lateral do pé direito e da perna. A ressonância magnética (RM) da perna direita revelou uma lesão bem-circunscrita, medindo 2,5 por 1 cm, mostrando hipointensidade nas sequências T1 e hiperintensidade em T2, compatível com um tumor superficial de células do nervo peronal. Foi realizada excisão cirúrgica da lesão e o exame histopatológico confirmou a suspeita inicial - Schwannoma do nervo peroneal superficial. O pós-operatório foi tranquilo, com melhora progressiva da dor e recuperação funcional completa sem déficits neurológicos. Exame clínico rigoroso associado aos exames de RM permitem diagnóstico adequado, bem como a exclusão de outras patologias com apresentação clínica semelhante. Assim, o cirurgião tem que estar atento a todos os dados para um diagnóstico e tratamento eficazes nesse tipo de patologia rara que não pode ser negligenciada.

Malignant peripheral nerve sheath tumor in a child.

Among the diverse causes of posterior mediastinal masses, malignant peripheral nerve sheath tumors is a very rare neurogenic tumor. Imaging features tend to be variable. A 20-month-old toddler presented with a 3-month history of persistent diffuse thoracic and abdominal pain. A chest magnetic resonance imaging was taken and shown a posterior mediastinal lesion. Histopathology and immunohistochemical analysis confirmed the diagnosis of a malignant peripheral nerve sheath tumor with myxoid areas. Malignant peripheral nerve sheath tumors are an uncommon entity in the children with a poor prognosis. Magnetic resonance imaging is the preferred technique in children to limit the use of ionizing radiation and because has a higher contrast resolution; however, all suspicious tumors should be biopsied to make an appropriate diagnosis. Treatment is radical surgery with excision of the entire mass; however, there is a high incidence of local recurrence.

Neurofibromas of the oral and maxillofacial complex: A 48-year retrospective study.

Neurofibromas are benign neoplasms of the peripheral nerve sheath, characterized by the proliferation of Schwann cells, perineural cells and endoneural fibroblasts. Their occurrence in the oral and maxillofacial complex is uncommon. This study aimed to evaluate the clinical and histopathological characteristics of neurofibromas of the oral and maxillofacial complex excised at our institution over a 48-year period. Using light microscopy, two previously trained oral pathologists re-evaluated all hematoxylin and eosin slides. From a total of 15,375 cases diagnosed at a referred Oral Pathology Service, 24 cases were diagnosed as neurofibromas. Eighteen neurofibroma patients were female, with a mean age of 39.1 years. Three patients presenting neurofibromas exhibited neurofibromatosis type I. Clinically, most of the lesions presented as asymptomatic nodules, and the most frequent sites were the tongue (n = 6; 25.0%), gingiva (n = 6; 25.0%) and intraosseous maxillary bone region (n = 3; 12.5%). Histopathologically, the lesions were predominantly well delimited, exhibiting interlocking bundles of spindle-shaped cells that usually displayed wavy nuclei, associated with delicate collagen fibers. Thus, knowledge of their clinical and histopathological features by dentists and oral pathologists is essential for the correct diagnosis of these lesions.

Neurofibromatosis Type 1 - Association with Breast Cancer, Basal Cell Carcinoma of the Skin, and Low-Grade Peripheral Nerve Sheath Sarcoma: Case Report and Literature Review.

Neurofibromatosis type 1 is a rare medical condition that raises the probability of having distinct types of malignant and benign neoplasms. Nevertheless, the association with breast cancer is rare, and metachronic neoplasia with a distinct histologic subtype is an association that has never been reported before. Here we describe a case of a primary breast tumor, with posterior development of basal cell carcinoma of the skin, and a low-grade peripheral nerve sheath sarcoma.

Mobile cauda equina schwannomas: How to deal with this rare event and avoid surgical complications.

BACKGROUND: Mobile schwannomas of the cauda equina are rare. Preoperative planning should take into consideration the possibility of tumor migration, avoiding unnecessary additional laminectomy or second operation. CASE DESCRIPTION: A patient with a previously known lumbar schwannoma was being managed conservatively until symptoms exacerbated and led to a new MR. When this study revealed caudal migration of the schwannoma from L3 to the L4-L5 levels, a right hemilaminectomy was performed for tumor resection. CONCLUSION: Great care must be taken in the surgical resection of schwannomas as they may migrate from their initial location.

Neurofibroma Cantal Solitario: Reporte de Caso / Canthal Solitary Neurofibroma

Objetivos: presentar el caso de una paciente que desarrolló un neurofibroma solitario de localización cantal interna. Diseño de estudio: reporte de caso. Métodos: se reporta el caso de una paciente con un neurofibroma solitario localizado en el canto interno, a la vez que se presenta una breve revisión bibliográfica sobre esta patología infrecuente. Conclusiones: el neurofibroma solitario es una patología infrecuente de naturaleza benigna que puede comprometer el globo ocular, el párpado y la órbita, por lo que debe ser considerado dentro de los diagnósticos diferenciales de la patología tumoral de estas áreas anatómicas.

Objectives: to report the case of a patient with a solitary neurofibroma in the medial canthal area. Study design: case report. Methods: report the case of a patient with a solitary neurofibroma in the medial canthal area and review the pertinent literature. Conclusions: the solitary neurofibroma is a rare benign condition with the potential to compromise the eye, the eyelid and the orbit, so that should be considered in the differential diagnosis of tumoral pathology in these anatomic areas. Keywords: nerve sheath neoplasms, peripheral nervous system neoplasms, neurofibroma.

Sequestered lumbar disc herniation mimicking spinal tumor / Hérnia de disco lombar sequestrada simulando tumor espinhal

The occurrence of herniated disc simulating diseases in neuroimaging it?s an uncommon situation. However, due to changes that occur in sequestered disc fragment, some cases can mimic spinal neoplasms. Thus, we present the case of a female patient, 60 year-old, with left back pain and left leg weakness. Left lower limb presented with strength grade IV, positive 45 degress Lasègue?s signal and patellar areflexia. Lumbar spine magnetic resonance imaging (MRI) showed an expansive left centro-lateral lesion at L4-L5 level, hypointense on T1W, hyperintense on T2W, with peripheral contrast uptake, causing compression of the dural sac and L5 nerve root. A hemilaminectomy was performed, with complete excision of the lesion. Histological analisys confirmed discal hernia. Disc herniation is a condition characterized by the displacement of the disc content to the spinal canal, predominantly in the lumbar region, and manifesting as radiculopathy. The fragment sequestration occurs in 30% of the cases and is characterized by loss of continuity with remaining disc. MRI exams generally allow diagnostic confirmation; however, there may be diagnostic confusion with tumors, arachnoid cysts and abscesses. The inflammatory reaction occurred in the disc fragment produces the differences in MRI signal. The fragment is hypointense on T1W, hyperintense on T2W, with peripheral enhancement after contrast. Malignancies and Schwannomas have homogeneous or heterogeneous uptake. The epidural abscess is isointense on T1W and hyperintense on T2W, with homogeneous or peripheral enhancement, similar to discal herniation. Thus, sequestered disc herniation can mimic other space-occupying lesions, being necessary a surgical approach to obtain material for histopathological analysis and diagnostic confirmation.

A ocorrência de hérnias de disco simulando outras patologias em neuroimagens é incomum. Entretanto, devido às alterações que ocorrem no fragmento discal sequestrado, alguns casos podem mimetizar neoplasias espinais. Assim, apresentamos o caso de uma paciente do sexo feminino, 60 anos, com lombalgia à esquerda e fraqueza na perna esquerda. O membro inferior esquerdo apresentava força grau IV, sinal de Laségue positivo a 45 graus e arreflexia patelar. Ressonância nuclear magnética (RNM) de coluna lombossacra evidenciou lesão expansiva centrolateral esquerda ao nível de L4-L5, hipointensa em T1, hiperintensa em T2, com captação periférica de contraste, determinando compressão do saco dural e raiz de L5. Realizou-se hemilaminectomia com excisão completa da lesão. A análise histológica confirmou hérnia discal. Hérnia de disco é uma patologia caracterizada pelo deslocamento do conteúdo discal para o canal vertebral, predominando na região lombar e manifestando-se como radiculopatia. O sequestro do fragmento ocorre em 30% dos casos e se caracteriza por perda da continuidade com o disco remanescente. Exames de RNM geralmente permitem a confirmação diagnóstica, entretanto, pode haver confusão diagnóstica com tumores, cistos aracnóideos e abscessos. A reação inflamatória ocorrida no fragmento discal produz as diferenças de sinal na RNM. O fragmento é hipointenso em T1, hiperintenso em T2, apresentando realce periférico após contraste. Neoplasias malignas e Schwannomas apresentam captação homogênea ou heterogênea. Os abscessos epidurais podem apresentar realce homogêneo ou periférico, semelhante às hérnias discais. Assim, hérnias de disco sequestradas podem mimetizar outras lesões ocupando espaço, sendo necessária abordagem cirúrgica com obtenção de material para análise histopatológica para confirmar o diagnóstico.

Intraoral nerve sheath myxoma: case report and systematic review of the literature.

BACKGROUND: Oral nerve sheath myxoma (NSM) is an uncommon benign neoplasm with Schwann-cell origin, which is frequently mistaken for neurothekeoma. We report a case of NSM on the buccal mucosa in a 42-year-old woman. This case is compared with previously reported cases and a systematic review is performed. METHODS AND RESULTS: We conducted a case report and systematic review of oral cases considered true NSMs. A literature search was performed using PubMed, Lilacs, Scielo, Cochrane, SciVerse Scopus, Web of Science, and Embase electronic database. Twenty-five cases of oral NSM were included in the systematic review. CONCLUSION: Oral NSM is rare and may represent a diagnostic challenge for pathologists. To confirm the diagnosis of NSM, the evaluation of S-100 protein expression or other neural marker is essential. The use of the terms NSM and neurothekeoma as synonymous or as variants of the same tumor should be avoided, because they are clearly distinct lesions.

Tumor maligno de la vaina del nervio periférico del mediastino en un paciente con neurofibromatosis tipo 1 / Mediastinal malignant peripheral nerve sheath tumor in a neurofibromatosis type 1 patient

El tumor maligno de la vaina del nervio periférico (TMVNP), es una neoplasia maligna originada en las células de Schwan de la vaina de revestimiento del nervio periférico. Describir el caso de un hombre con neurofibromatosis tipo 1 (NF1), quién presentó un TMVNP de bajo grado, y realizar una discusión sobre esta enfermedad. Hombre de 28 años, con antecedente de NF1 diagnosticada a los 15 años de edad, con dolor pleurítico izquierdo, disnea y pérdida de peso de 10 meses de evolución. Al examen de tórax, se observó marcada hipercifosis dorsal con disminución del murmullo pulmonar. La radiografía de tórax y tomografía axial computarizada (TAC), evidenciaron gran masa radioopaca bien delimitada en mediastino posterior. Por lo anterior, se realizo biopsia por punción con aguja gruesa guiada por TAC, en la cual se identificó una neoplasia maligna mesenquimal. Se decidió realizar resección del tumor a través de toracotomía posterolateral, en la que se obtuvo gran masa de 8x9x9 cm, de superficie externa irregular, pardo-violácea y consistencia firme. El estudio histopatologico e inmunofenotípico concluyo el diagnóstico de TMVNP en mediastino posterior Grado 1. Posterior a la cirugía, el paciente se encuentra asintomático. Se presentó un caso de TMVNP originado en un paciente con NF1, presentación que generalmente cursa con peor pronóstico, además se realizo una breve revisión de los aspectos más relevantes de esta enfermedad, algunos de los cuales han tenido un avance vertiginoso en años recientes.

The malignant peripheral nerve sheath tumor (MPNST) is a malignant neoplasm originated in the Schwan cells of the periferic nerves sheath. We describe a case of a man with Neurofibroatosis Type 1 (NF1), who developed a low grade MPNST, and subsequent to a discussion of this disease. 28-year-old Man with pleuritic pain in the left hemithorax, dyspnea and weight loss, with a previous diagnosis of NF1, from the age of 15 and a family history of NF1. At chest examination the patient had an intense thoracic kyphosis, with a decline in the ventilation of the inferior two thirds of the left hemithorax, where a dull sound to percusión was also found. The chest X rays showed a large radiopaque and well delimited mass in the posterior mediastinum, that pushed the cardiovascular structures to the anterior region, which was also documented by chest computed tomography (CT). In view of the above, a puncture biopsy was performed with thick needle guided by CT, from where a malignant mesenhymal neoplasm was identified. It was decided to perform the resection of the tumor of the left posterior mediastinum, by left posterior lateral thoracotomy, in which a large mass of 8x9x9 cm was obtanied, with irregular external surface, brown-violet, and firm. The histopathological and inmunophenotypic study concluded the diagnosis of MPNST in the posterior mediastinum grade 1. Following surgery the patient was asymptomatic. We present a case of MPNST which originated in a patient with NF1, who would usually have a worse prognosis. A brief review of the more relevant aspects of this disease was also reported, some of which have shown important progress in recent years.

Ileal perineurioma as a cause of intussusception / Perineurioma ileal como uma causa de intussuscepção

CONTEXT: Perineuriomas are rare tumors composed of cells resembling those of the normal perineurium. It usually occurs in subcutaneous, soft-tissue or intraneural locations. Very few reports in the literature have described perineuriomas in the gastrointestinal tract, including the stomach, colon and jejunum. CASE REPORT: We report the clinicopathological and immunohistochemical features of a case of ileal perineurioma that was manifested clinically as intestinal obstruction due to intussusception. Ileal perineurioma has not previously been reported at this anatomical location.

CONTEXTO: Perineurioma é uma rara neoplasia composta de células que lembram aquelas do perineuro normal e geralmente ocorre no subcutâneo, tecidos moles ou em localização intraneural. Poucos relatos na literatura descrevem perineuriomas no trato gastrointestinal incluindo estômago, cólon e jejuno. RELATO DE CASO: Os autores apresentam as características clinicopatológicas e imunoistoquímicas de um caso de perineurioma ileal apresentando-se clinicamente por obstrução intestinal decorrente de intussuscepção. Perineurioma ileal não havia sido descrito até o momento nessa localização anatômica.

Perineurioma esclerosante: relato de caso e revisão da literatura / Sclerosing perineurioma: case report and literature review

O perineurioma esclerosante é uma neoplasia benigna rara,constituída exclusivamente por células com diferenciação perineural, dispersas em meio a estroma fibroso denso. Acomete preferencialmente a pele dos quirodáctilos e das regiões palmares e se apresenta como pápula ou nódulo firme, normocrômico e assintomático. Apresentamos um caso de perineurioma esclerosante localizado na região palmar esquerda de uma paciente feminina de 16 anos de idade, com detalhada demonstração dos aspectos clínicos, histopatologia e revisão da literatura publicada em língua inglesa.

Sclerosing perineurioma is a rare benign neoplasm composed exclusively of perineural differentiation cells spread in a dense fibrous stroma. It affects primarily the skin of fingers and that of the palm of the hands. It appears as a hard papule or nodule, normochromic and asymptomatic. A case of sclerosing perineurioma in the left palm of a 16-year-old female is described, with detailed demonstration of clinical aspects, histopathology and literature review published in the English language.

Um caso raro de tumores torácicos malignos sincrônicos / A rare case of synchronous malignant thoracic tumors

Tumores neurogênicos malignos do mediastino em adultos são raros e extremamente agressivos. Este artigo relata o caso de um paciente de 61 anos com a ocorrência simultânea de schwannoma maligno de mediastino e carcinoma bronquíolo-alveolar. Apesar do carcinoma bronquíolo-alveolar estar presente em 4-7 por cento dos tumores torácicos sincrônicos ressecados, essa associação nunca foi apresentada na literatura. É, no entanto, um achado frequente em pacientes com infiltrados aparentemente inflamatórios e com opacidades em vidro fosco, como apresentado neste caso.

Malignant neurogenic mediastinal tumors in adults are uncommon and extremely aggressive. We report the case of a 61-year-old male patient with the simultaneous occurrence of malignant mediastinal schwannoma and bronchioloalveolar carcinoma. Although bronchioloalveolar carcinoma is present in 4-7 percent of the resected synchronous thoracic tumors, this association has never been reported in the literature. However, it is a common finding in patients presenting apparently inflammatory infiltrates and ground-glass opacities, as in the case presented here.

Retrospective analysis of oral peripheral nerve sheath tumors in Brazilians

Traumatic neuroma, neurofibroma, neurilemmoma, palisaded encapsulated neuroma and malignant peripheral nerve sheath tumor (MPNST) are peripheral nerve sheath tumors and present neural origin. The goal of this study was to describe the epidemiological data of oral peripheral nerve sheath tumors in a sample of the Brazilian population. Biopsies requested from the Oral Pathology Service, School of Dentistry, Federal University of Minas Gerais (MG, Brazil), between 1966 and 2006 were evaluated. Lesions diagnosed as peripheral nerve sheath tumors were submitted to morphologic and to immunohistochemical analyses. All cases were immunopositive to the S-100 protein. Thirty-five oral peripheral nerve sheath tumors were found, representing 0.16% of all lesions archived in the Oral Pathology Service. Traumatic neuroma (15 cases) most frequently affected the mental foramen. Solitary neurofibroma (10 cases) was more frequently observed in the palate. Neurofibroma associated with neurofibromatosis type I (2 cases) was observed in the gingival and alveolar mucosa. Neurilemmoma (4 cases) was more commonly observed in the buccal mucosa. Malignant peripheral nerve sheath tumors (3 cases) occurred in the mandible, palate, and tongue. Palisaded encapsulated neuroma (1 case) occurred in the buccal mucosa. The data confirmed that oral peripheral nerve sheath tumors are uncommon in the oral region, with some lesions presenting a predilection for a specific gender or site. This study may be useful in clinical dentistry and oral pathology practice and may be used as baseline data regarding oral peripheral nerve sheath tumors in other populations.

Description of a neural sheath tumor of the trigeminal nerve: immunohistochemical and electron microscopy study

CONTEXT: Malignant neural sheath tumors of the trigeminal nerve affecting the nasal cavity and the paranasal sinuses are extremely rare. With conventional optical microscopy, their identification is difficult, and it is necessary to confirm them by means of electron microscopy and immunohistochemical techniques. CASE REPORT: The patient was a 41-year-old woman with a ten-month progressive history of pain followed by painful edema in the left facial region, and with symptoms of bleeding, secretion and nasal obstruction. Studies with imaging methods suggested the presence of an expansive process in the left nasal and paranasal cavities. In the biopsy, the histopathological findings from optical microscopy were suggestive of a tumor of neural origin in the trigeminal nerve. Immunohistochemical and electron microscopy studies confirmed that it was a malignant tumor of the neural sheath of the trigeminal nerve. We describe the clinical, radiological, and histological features of this tumor and review the literature.

CONTEXTO: O tumor maligno da bainha neural do trigêmeo que acomete a cavidade nasal e os seios paranasais é extremamente raro. A microscopia óptica habitual sua identificação é difícil, sendo necessária a confirmação através de microscopia eletrônica e de técnicas imunoistoquímicas. RELATO DE CASO: A paciente era uma mulher de 41 anos com história de 10 meses de progressiva dor seguida de edema álgico em região facial à esquerda, e de sintomas de sangramento, secreção e obstrução nasal. Estudos com métodos de imagem sugeriam a presença de processo expansivo em cavidades nasais e paranasais à esquerda. A biopsia, os achados histopatológicos à microscopia óptica foram sugestivos de tumor de origem neural no trigêmeo. Estudos imunoistoquímico e por microscopia eletrônica confirmaram se tratar de neoplasia maligna da bainha neural do trigêmeo. Descrevemos as características clínicas, radiológicas e histológicas deste tumor, e revisamos a literatura.