Schwannomas at unusual locations: a case series

Schwannoma, also known as neurinoma or neurilemmoma, is a benign, encapsulated, slow-growing, peripheral nerve sheath tumor arising from the Schwann cells. They are seen mostly in the head and neck region, with the 8th cranial nerve being the most common site. There it is known as vestibular Schwannoma or acoustic neuroma. It is usually seen in 20� years of age, with no specific sex or racial predilection. Histopathologically, there may be compact hypercellular Antoni A areas and myxoid hypocellular Antoni B areas. Nuclear palisading around fibrillary processes, also known as Verocay bodies, is often seen in cellular areas. In this article, we present a series of cases where all of the patients presented to us with soft tissue swelling for varying periods of time in different locations, mostly in extremities. Cytopathology and radiology couldn抰 come to a specific diagnosis. The tumors were excised en mass. The post-operative histology of the excised tumor confirmed the diagnosis of Schwannoma, arising from peripheral nerve sheath. There was no recurrence after follow up for 1 year. Schwannomas most commonly arise from the peripheral nerve sheaths usually at the head neck region. They are seen rarely in other peripheral nerves. They should be excised en mass with intact epineurium. After complete excision their recurrence rate is very low thus having a good prognosis.

Schwannoma de colon derecho: a propósito de un caso / Schwannoma of the right colon: case report

RESUMEN El schwannoma de colon es una entidad sumamente rara que puede debutar como lesión subepitelial con signos ulcerativos de melena y anemia. El estudio de imágenes nos orienta a la localización mientras que la biopsia colonoscópica no es de ayuda. Muchas veces el diagnóstico y tratamiento se efectúa con la resección de la lesión en tanto que el diagnóstico final se realiza en el posoperatorio por histopatología y por la inmunohistoquímica, la cual muestra positividad intensa para S100 y vimentina en las células tumorales con un índice de proliferación KI67 menor al 1%, por lo que se concluye que se trata de una lesión benigna. Presentamos el siguiente caso por su dificultad diagnóstica pre e intraoperatoria, clínica inespecífica y diagnóstico definitivo por inmunohistoquímica.

ABSTRACT Colon schwannoma is an extremely rare entity that may debut as a subepithelial lesion with ulceration signs, such as melena and anemia. Imaging studies guide us to localization, while a colonoscopy biopsy is not helpful. Many times, the diagnosis and treatment are made with lesion resection, and the final diagnosis is postoperatively made with histopathology and immunohistochemistry, which shows intense positivity for S100 and vimentin in tumor cells with a KI67 proliferation index of less than 1%, therefore, it is concluded that this is a benign lesion. We present this case due to its pre- and intraoperative diagnostic difficulty, non-specific symptoms, and its definitive diagnosis that was achieved with immunohistochemistry.

Posterior Interosseous Nerve Syndrome due to Schwannoma - A Case Report / Síndrome interóssea posterior devido a schwannoma - Um relato de caso

Abstract Posterior interosseous nerve syndrome is the most frequent syndrome of radial nerve compression, with the arcade of Frohse being the main site of compression. Its symptoms include difficulties in finger and wrist extension with possible radial deviation. Herein, we present a case of posterior interosseous syndrome caused by a schwannoma, a type of neurological tumor.

Resumo A síndrome interóssea posterior é a síndrome mais frequente de compressão do nervo radial, com a arcada de Frohse sendo o principal local de compressão. Seus sintomas incluem dificuldades na extensão do dedo e punho, com possível desvio radial. Aqui, apresentamos um caso de síndrome interóssea posterior causada por um schwannoma, um tipo de tumor neurológico.

Benign cervical schwannoma with tracheal invasion

ABSTRACT Schwannomas commonly develop in the cervical region, 25% - 45% of cases are diagnosed in this anatomical region. Tracheal neurogenic tumors are exceedingly rare and can be misdiagnosed as invasive thyroid carcinomas or other infiltrating malignancies when present at the level of the thyroid gland. Here, we present a case of synchronous benign cervical schwannoma with tracheal invasion and papillary thyroid carcinoma in a patient who was initially hospitalized for COVID-19. The patient presented with dyspnea that was later found to be caused by tracheal extension of a cervical tumor. Surgical excision was performed, and the surgical team proceeded with segmental tracheal resection, removal of the cervical mass, and total thyroidectomy. The specimen was sent for pathological analysis, which revealed synchronous findings of a benign cervical schwannoma with tracheal invasion and papillary thyroid carcinoma. The literature on this subject, together with the present case report, suggests that neurogenic tumors should be included in the differential diagnosis of obstructing tracheal cervical masses. Surgical excision is the first-line of treatment for benign cervical schwannomas.

Schwannoma retroperitoneal primario. Presentación de un caso

Los schwannoma son tumores de tejidos blandos que se originan en las células de Schwann de la vaina nerviosa en los nervios periféricos, craneales o viscerales, en cualquier parte del cuerpo. Se trata de una entidad extremadamente inusual. En el artículo se describe el caso de un paciente de piel negra, 47 años de edad y con antecedentes de salud, quien acudió a consulta de clasificación, refiriendo que desde hacía un mes había comenzado a presentar dificultad para orinar, hasta llegar a la retención aguda de orina. Al examen físico se constató, mediante tacto rectal, esfínter tónico, ampolla rectal vacía, próstata aumentada de tamaño grado IV con consistencia fibromuscular de superficie lisa y móvil; no dolorosa. Tras realizarle estudios imagenológicos y complementarios, recibió tratamiento quirúrgico en el Hospital Provincial Docente Oncológico María Curie, de Camagüey, Cuba. Se le diagnosticó un schwannoma retroperitoneal, confirmado por el informe de Anatomía Patológica. Actualmente la evolución del paciente es favorable, sin tratamiento médico, pero con seguimiento periódico.

Schwannoma are soft tissue tumors that originate in Schwann cells of the nerve sheath in peripheral, cranial or visceral nerves, anywhere in the body. This is an extremely unusual entity. The article describes the case of a 47-years-old black-skinned patient with a history of health who attended a triage consultation, reporting that one month ago he had started having difficulty urinating, leading to acute urinary retention. The physical examination confirmed, through digital rectal examination, a tonic sphincter, an empty rectal ampulla, a grade IV enlarged prostate with a fibromuscular consistency with a smooth and mobile surface; not painful. After carrying out imaging and complementary studies, he received surgical treatment at the María Curie Provincial Oncological Teaching Hospital, in Camagüey, Cuba. He was diagnosed with a retroperitoneal schwannoma, confirmed by the Pathology report. Currently the evolution of the patient is positive, without medical treatment, but with periodic follow-up.

Schwannoma intraóseo en fémur, una presentación inusual. Reporte de caso / Intraosseous Schwannoma in femur, an unusual presentation. Case report

El Schwannoma o Neurilemoma es un tumor benigno de derivación neuroectodérmica que se origina en las células de Schwann, que constituyen la envoltura de los nervios. Es el tumor benigno más común de los nervios periféricos, tiene predisposición a originarse a partir de nervios periféricos sensoriales y puede presentarse como tumores en tejidos blandos. La presentación intraósea del Schwannoma es rara y corresponde al 0,2% de los tumores óseos primarios. Se presenta caso clínico de paciente masculino de 36 años de edad con tumor en cóndilo femoral medial de rodilla derecha de 4 años de evolución, cursando con dolor intermitente moderado a quien se le practicó el protocolo oncológico, imagenológico e histológico, de la Unidad de Oncología Ortopédica del estado Monagas. Se diagnosticó Schwannoma intraóseo, se procedió a realizar resección marginal y reconstrucción con alloinjerto y fijación con placa y tornillos con excelente evolución postoperatoria. El Schwannoma intraóseo es extraordinariamente raro y su ubicación en el fémur lo es aún más. El objetivo del presente trabajo es reportar un caso de Schwannoma Intraóseo, mostrar las estrategias para su diagnóstico y los tratamientos aplicados, así como la revisión de los datos al respecto existentes en la literatura(AU)

Schwannoma or Neurilemoma is a benign tumor of neuroectodermal derivation that originates in Schwann cells, which constitute the nerve sheath. It is the most common benign tumor of the peripheral nerves, has a predisposition to originate from peripheral sensory nerves, and can present as soft tissue tumors. The intraosseous presentation of Schwannoma is rare and corresponds to 0,2% of primary bone tumors. A clinical case of a 36-yearold male patient with a tumor in the medial femoral condyle of the right knee of 4 years of evolution is presented, presenting with moderate intermittent pain who underwent the oncological, imaging and histological protocol of the Oncology Unit. Monagas State Orthopedic. Intraosseous Schwannoma was diagnosed, marginal resection and allograft reconstruction and plate and screw fixation were performed with excellent postoperative evolution. Intraosseous Schwannoma is extraordinarily rare and its location in the femur is even more so. The objective of this paper is to report a case of Intraosseous Schwannoma, show the strategies for its diagnosis and the treatments applied, as well as the review of the existing data in the literature(AU)

Schwanoma palatino en paciente pediátrico de 12 años: una rara presentación clínica / Palatine Schwannoma in a 12 year-old pediatric patient: a rare clinical presentation

El schwanoma es un tumor neural que se origina en las células de Schwann presentes en la vaina nerviosa cuya localización más frecuente a nivel oral es el dorso de lengua, siendo mucho más frecuente en adultos. En población pediátrica la presentación es muy rara siendo lengua su ubicación más frecuente, mientras que a nivel palatino solo se conocen 11 reportes en menores de 16 años. El objetivo de este reporte es presentar un caso clínico inusual de schwanoma palatino en un niño chileno de 12 años de edad, quien fue derivado con diagnóstico clínico presuntivo de carcinoma mucoepidermoide. El caso se complementó con radiografía panorámica, Conebeam, y luego biopsia incisional. Finalmente, se diagnosticó schwanoma palatino variedad sólida. Es importante considerar al schwanoma como diagnóstico diferencial en casos de tumores palatinos, en especial en casos pediátricos ya que se pueden presentar similares características clínicas a tumores de glándula salival.

The Schwannoma or neurilemmoma tumor originates from Schwann cells present in nerve sheaths. At oral level, its most frequent location is at the back of the tongue, being much more frequent in adults. In the pediatric population, this occurrence is rare and most frequently found in the tongue. At palatal level, only 11 reports are known in children under 16 years of age. The aim of this report is to present an unusual clinical case of palatal schwannoma in a 12-year-old Chilean boy, referred with a clinical diagnosis of mucoepidermoid carcinoma. The case was complemented with panoramic radiography and Cone beam, for its subsequent incisional biopsy. Finally, a solid palatal schwannoma was diagnosed. It is important to consider schwannoma as a differential diagnosis in cases of palatal tumors, especially in pediatric cases, since they can present similar clinical characteristics to salivary gland tumors.

Surgical analysis of anterior cervical approache in the treatment of brachial plexus schwannoma of thoracic outlet / 国际外科学杂志

Objective:To investigate the surgical treatment strategies of brachial plexus schwannomas protruding from the foraminal area to the thoracic outlet through anterior cervical approach, and to evaluate the curative effect.Methods:The clinical data of 8 patients treated in Beijing Friendship Hospital Affiliated to Capital Medical University from July 2016 to December 2020 who underwent supraclavicular cervical "barb" incision for protruding into the thoracic outlet through anterior cervical approach were retrospectively collected, including 5 males and 3 females, aged (50.75±11.14) years old, ranging from 31-66 years old. And the key points of the operation, postoperative complications and postoperative follow-up were analyzed. Measurement data with normal distribution were represented as mean±standard deviation( ± s), count data were described as numbers. Results:The tumors in all 8 cases were totally resected.The amount of bleeding during operation was (35.00±14.14) mL. No surgical complications such injury of pleura, aspneumothorax and hemothorax, except 2 cases which developed local sensory disturbance that improved that after neurotrophic treatment and hormonotherapy. All 8 patients were followed up by outpatient or telephone for 1-5 years, and cervical MRI review showed no tumor recurrence in situ.Conclusions:The anterior cervical approach with "barb type" incision above the neck clavicle is effective in excision of schwannomas protruding into the thoracic outlet, with less intraoperative injury, less blood loss, fast postoperative recovery.

The value of CT for differentiating gastric leiomyoma from gastric schwannoma / 中国医师进修杂志

Objective:To evaluate the value of CT for differentiating gastric leiomyoma (GLM) from gastric schwannoma (GS).Methods:The clinical and imaging data of 42 patients with GLM (GLM group) and 41 patients with GS (GS group) were analyzed retrospectively. The general information and CT features were compared between two groups. The independent factors for differentiating GLM from GS were obtained by multivariate Logistic regression analysis. The receiver operating characteristic curve (ROC) was used to evaluate the diagnostic efficiency of the model.Results:The proportion of female and age in GLM group were significantly lower than those in GS group: 59.52% (25/42) vs. 85.37% (35/41), (51.83 ± 10.52) years old vs. (58.80 ± 10.63) years old, and there were statistical differences ( P<0.01). The upper part of the stomach rate, irregular shape rate, intraluminal growth rate, ratio of long diameter to short diameter and mild to moderate enhancement rate in GLM group were significantly higher than those in GS group: 71.43% (30/42) vs. 14.63% (6/41), 52.38% (22/42) vs. 21.95% (9/41), 92.86% (39/42) vs. 19.51% (8/41), 1.90 ± 0.55 vs. 1.34 ± 0.28 and 92.86% (39/42) vs. 51.22% (21/41), the cystic degeneration rate, ulcer rate, incidence of tumor-associated lymph node, CT values of venous phase and delayed phase in GLM group were significantly lower than those in GS group: 2.38% (1/42) vs. 26.83% (11/41), 7.14% (3/42) vs. 24.39% (10/41), 2.38% (1/42) vs. 60.98% (25/41), (59.21 ± 9.75) HU vs. (66.22 ± 10.33) HU and (65.02 ± 8.62) HU vs. (76.85 ± 11.89) HU, and there were statistical differences ( P<0.01 or <0.05); there were no statistical difference in the rate of calcification and the CT values of plain scan and arterial phase between the two groups ( P>0.05). Multivariate Logistic regression analysis result showed that the tumor location, growth mode, tumor-associated lymph node and ratio of long diameter to short diameter were the independent factors for differentiating GLM from GS ( OR = 34.385, 25.314, 0.023 and 97.700; 95% CI 2.848 to 415.171, 2.674 to 239.670, 0.001 to 0.637 and 3.113 to 3 066.549; P<0.01 or <0.05); when the model threshold was >0.647, the area under the curve was 0.988 (95% CI 0.934 to 1.000), with a sensitivity of 92.9% and specificity of 97.6%. Conclusions:When the tumor is prone to the upper part of the stomach, intraluminal growth, ratio of long diameter to short diameter >1.28, and the absence of the tumor-associated lymph node, GLM tends to be considered, on the contrary, it tends to be GS. Therefore, CT imaging features have certain value in differentiating GLM from GS before surgery.

Clinical distribution of primary intracranial tumors and risk factors for postoperative complications / 中国神经精神疾病杂志

Objective To examine the clinical distribution of primary intracranial tumors and analyze the risk factors for postoperative complications.Methods From January 2018 to December 2022,the clinical data of 961 patients with primary intracranial tumor in the Department of Neurosurgery of Tiantan Hospital in Beijing were collected and analyzed retrospectively.To examine the clinical distribution of patients with primary intracranial tumor and present the incidence of postoperative complications.To compare the basic data of patients with and without postoperative complications,and analyze the risk factors leading to postoperative complications.Results There were 363 cases of glioma,231 cases of meningioma,158 cases of sellar tumors,142 cases of neurilemmoma and 67 cases of other types of tumors.There were 679 cases of supratentorial tumors and 282 cases of infratentorial tumors.Postoperative complications occurred in 279 patients,and the incidence of postoperative complications was 29.03％.The incidences of intracranial infection,pulmonary infection,hyponatremia,lower extremity venous thrombosis and central nervous system infection were 9.37％,5.41％,4.99％,4.47％and 4.27％,respectively.After surgery,D-dimer(D-D),fibrin degradation products(FPD),prothrombin time(PT)in patients with primary intracranial tumors were significantly higher than those in patients without primary intracranial tumors(P<0.05).Activation of partial thromboplastin time(APTT),and thrombin time(TT)levels were significantly higher than those before surgery(P<0.05).Fibrinogen(FIB)was significantly lower than that before surgery(P<0.05).There were significant differences in tumor location,intraoperative blood loss,operation time,anesthesia recovery time and postoperative coagulation function between patients with and without postoperative complications(P<0.05).Conclusions The common types of primary intracranial tumors include gliomas,meningiomas,sellar tumors and neurilemmoma,etc.Surgical treatment has a high risk of postoperative complications.Common postoperative complications include intracranial infection,pulmonary infection,hyponatremia,lower extremity venous thrombosis,and central nervous system infection.Tumor location,operation duration,intraoperative blood loss,anesthesia recovery time and postoperative coagulation dysfunction are all risk factors for postoperative complications.

Maxillary Schwannoma – A Rare Case Report

Background: Schwannoma or neurilemmoma are a type of nerve sheath tumors. Most of the literature, reports of schwan- noma in the head and neck involve tongue. Intraosseous schwannomas account to about less than 1% with affliction to the mandible over maxilla. Very few cases of maxillary schwannomas have been reported till date. Case presentation: We present one such rare case of schwannoma involving the maxilla extending till the nasal cavity in a 35 years old male. Wide excision of the lesion with hemi-maxillectomy of the right side was done using modified Weber–Fergusson approach (Dieffenbach’s extension). The patient’s postoperative recovery was uneventful without recurrence when followed up till 2 years. Conclusion: Though schwannoma of the Head and neck region are rare, they should be considered as a differential diagnosis of unilateral slow growing mass in the head and neck region, particularly in an adult.

Cellular Schwannoma of Buccal Mucosa: A Rare Histopathological Variant

Introduction: Schwannoma (Neurilemmoma) is a benign neoplasm that develop from schwann cells in the peripheral nerve sheath. It commonly occurs as an encapsulated, slow-growing and generally solitary lesion. Cellular schwannoma is a rare histopathological variant of schwannoma. Case Presentation: Here, we discuss a case of 44-year-old female patient who reported with the chief complaint of swelling in the left upper back cheek region for the past 2 years. Histopathological and immunohistochemical analysis confirmed the diagnosis as cellular schwannoma. Management and prognosis: Surgical excision of the lesion was performed and no recurrence was reported after 1 year of follow up. Conclusion: Cellular schwannoma a rare intraoral benign tumor, needs to be differentiated from other malignant tumor with a careful approach for a prompt diagnosis and proper management of the lesion

Extracranial non-vestibular head and neck schwannomas: a case series with the review of literature

Abstract Introduction: Schwannomas are tumous that arise from Schwann cells. Schwannoma is one of the differential diagnosis for lateral neck swelling. Objective: In this study, we aim to describe the incidence, presenting clinical features and management of extracranial, non-vestibular schwannomas of head and neck region, along with the review of the literature. Methods: Patients treated at our tertiary care hospital for head and neck schwannomas for the past 15 years were included in the study. A review of literature on the extracranial head and neck schwannoma was also done. Results: Twenty-five cases were assessed in this study. Nineteen cases presented as a neck swelling during the initial evaluation. Vagus nerve was the most common nerve of origin, followed by the cervical sympathetic plexus. A rare presentation arising from brachial plexus C5 nerve root was also encountered. A few rare cases of schwannomas arose from the nasal cavity, paranasal sinuses, and oral cavity. Surgical excision was done in all the cases with histopathology suggestive of schwannoma. The nerve of origin of the tumor was identified in nineteen patients. Among them, 11 (58%) were from the vagus nerve, 7 (37%) from the cervical sympathetic chain, and 1 (4%) from the brachial plexus C5 nerve root. Conclusion: A long-standing unilateral neck mass is the most common presenting complaint in head and neck schwannoma. The diagnosis is mainly based on clinical features and investigations such as imaging. The mainstay of treatment is complete surgical excision. The diagnosis is confirmed on the histopathological study after excision of the lesion. Due to the proximity of the tumor with the involved nerve, palsy may occur. Hence, an accurate preoperative diagnosis of schwannoma is essential.

Schwannoma intraóseo mandibular: reporte de un caso clínico / Mandibular intraosseous schwannoma: a clinical case report

Objetivo: El schwannoma es un tumor neuroectodérmi- co benigno de la vaina nerviosa o vaina de mielina formada por células de Schwann. Aproximadamente entre el 25 y el 48% de los casos presentan localización en el territorio cer- vicofacial, especialmente en los tejidos blandos de esta re- gión. Se los puede clasificar como schwannomas periféricos o intraóseos, éstos últimos también denominados centrales. Los schwannomas intraóseos son poco comunes, constituyen menos del 1% de los schwannomas presentes en la región en cuestión y menos del 0,2% de todos los tumores primarios óseos. El presente trabajo tiene como objetivo reportar un caso clínico de un schwannoma intraóseo mandibular, revi- sando aspectos clínicos, radiográficos y anatomopatológicos. El schwannoma intraóseo es una entidad poco común, o al menos se encuentra en una condición de subregistro en Argen- tina, por lo que este caso constituye una rareza. Caso clínico: Se presentó a la consulta una paciente de 30 años de edad, derivada al servicio de Cirugía y Trau- matología Bucomaxilofacial del Hospital "Parmenio Piñero" de la Ciudad Autónoma de Buenos Aires por su odontólogo de cabecera, a raíz de un hallazgo radiográfico durante un control de rutina. Se planificó realizar una biopsia incisio- nal, cuyo resultado anatomopatológico fue compatible con el diagnóstico de schwannoma intraóseo. Se procedió a realizar la enucleación completa. Finalmente, la paciente evolucionó sin complicaciones (AU)

Aim: Schwannoma is a benign neuroectodermal tumor of the nerve sheath or myelin sheath formed by Schwann cells. Approximately between 25 and 48% of the cases are located in the cervicofacial territory, especially in the soft tissues of this region. They can be classified into peripheral and intraosseous schwannomas, the last one can also be reported as central. In- traosseous schwannomas are rare, constituting less than 1% of schwannomas present in the region and less than 0.2% of all primary bone tumors. This publication aims to report a clin- ical case of mandibular intraosseous schwannoma, reviewing clinical, radiographic and anatomopathological aspects. In- traosseous schwannoma is a rare entity, or at least is under a condition of underreport in Argentina, so this case is a rarity. Clinical case: A 30-year-old patient, referred to the Buccomaxillofacial Surgery and Traumatology service of the "Parmenio Piñero" Hospital of Ciudad Autónoma de Bue- nos Aires by her dentist, because of a radiographic finding during a routine check. An incisional biopsy was performed, the anatomopathological result of which was compatible with the diagnosis of intraosseous schwannoma. A complete enu- cleation was performed under local anesthesia. Finally, the patient evolved without complications (AU)

Clinical analysis of 19 patients with gastrointestinal schwannoma / 中国综合临床

Objective:To investigate the clinical features, diagnosis, treatment and prognosis of gastrointestinal neurilemmoma.Methods:A descriptive study was conducted to retrospectively analyze the clinical manifestations, endoscopic findings, pathological features, treatment methods and prognosis of patients with gastrointestinal neurilemmima diagnosed from May 2017 to November 2020 in the Second Affiliated Hospital of Xi'an Jiaotong UniversityResults:A total of 19 patients were collected, ranging in age from 45.0 to 70.0 years old, of whom 68.4% (13/19) were female. The clinical symptoms are non-specific, and some patients are asymptomatic (15.8%(3/19)) and may present with abdominal pain (57.9%(11/19)), nausea (31.6%(6/19)), abdominal distension (21.1%(4/19)) and decreased appetite (21.1%(4/19)), and a few with gastrointestinal bleeding (5.3%(1/19)). Tumors were most frequently found in the gastric body (42.1%(8/19)), followed by the duodenum (15.8%(3/19)). Endoscopic submucosal mass is easy to be misdiagnosed as stromal tumor. The pathological type showed shuttle cell tumor, immunohistochemical staining showed positive S100 and Vim, most Ki-67 staining proliferation rate was <5% (57.9%(11/19)), and a small part was ≥10% (10.5%(2/19)). Treatment was either endoscopic or surgical. No tendency to recur and metastasize was found in any of the neurilemmimas.Conclusion:Gastrointestinal neurilemmoma is a very rare submucosal tumor of the digestive tract, most of which are benign and rare in malignancy, and postoperative pathology is the gold standard for its diagnosis. Gastrointestinal neurilemmoma is common in middle-aged female, with diverse and non-specific clinical symptoms, difficult to differentiate from submucosal tumors such as stromal tumors, and its tendency to malignant transformation increases with tumor enlargement. Endoscopic resection is recommended for tumors with tumor diameter <3 cm without serosal invasion, with little trauma and no recurrence.

Benign glandular schwannoma

ABSTRACT We report a case of a benign glandular schwannoma in a 63-year-old male who presented with a solitary subcutaneous mass on the left knee, with no previous history of neurofibromatosis type 1. This histological subtype is rare, with only 38 cases reported in the literature. Some of the glands found in this patient resembled sweat glands. These lining stromal spindle cells were positive for S-100 but negative for EMA. S100 was faintly staining the glandular elements. All the glands in the tumor were positive for EMA, particularly at the luminal borders. They were also positive for pancytokeratin. The cystic areas variably show intraluminal, foamy, and hemosiderin-laden macrophages. The different glands expressed two patterns. Some of these were reactive for CK7 and low molecular weight keratin. Immunohistochemical workup is mandatory to assess the neoplastic nature of this glandular component.

Multiple neuroendocrine neoplasia in a patient with type i neurofibromatosis (nf1): report of a new mutation (nf1, exons 2-30 deletion) and literature review / Neoplasia neuroendócrina múltipla em doente com neurofibromatose tipo 1 (nf1). descrição de uma nova mutação e revisão da literatura

ABSTRACT BACKGROUND: Plexiform neurofibromas represent a common neoplasia of type 1 neurofibromatosis in which neurofibromas arise from multiple nerves involving connective tissue and skin and rarely affect the colon and rectum. Co-occurrence of plexiform neurofibromas, neuroendocrine tumors with primary involvement of the rectum, and medullary thyroid carcinoma in patients with neurofibromatosis type 1 is a previously undescribed condition. The aim of this manuscript was to present a case of primary plexiform neurofibroma and neuroendocrine tumors of the upper rectum in a patient with neurofibromatosis type 1 whose genetic sequencing found a novel mutation in the neurofibromatosis type 1 gene and to review the literature. CASE REPORT: A 49-year-old woman with a familial history of neurofibromatosis type 1 complained of abdominal cramps for 6 months. She had previously been submitted for a total thyroidectomy due to medullary thyroid carcinoma. She was submitted to a colonoscopy, which identified a submucosa lesion located in the upper rectum. The patient was referred for a laparoscopic rectosigmoidectomy, and the histopathological study of the surgical specimen identified two different tumors. An immunohistochemical panel was done for histopathological confirmation of the etiology of both lesions. The results of the panel showed intense immunoexpression of S100 protein in the largest and superficial lesion, as well as positivity for chromogranin and synaptophysin in the minor and deep lesion confirming the diagnosis of rectal plexiform neurofibromas concomitant with neuroendocrine tumors. The proliferative activity rate using Ki-67 antibodies showed that both tumors had a low rate of mitotic activity (<1%). Genetic sequence panel identified an undescribed mutation in the neurofibromatosis type 1 gene (deletion, exons 2-30). The patient's postoperative evolution was uneventful, and she remains well, without recurrence, 3 years after surgery. CONCLUSION: The co-occurrence of medullary thyroid carcinoma, plexiform neurofibromas, and neuroendocrine tumors of the rectum in patients with neurofibromatosis type 1 is an exceptional and undescribed possibility, whose diagnosis can be confirmed by the immunohistochemical staining and genetic panel.

RESUMO RACIONAL: Os neurofibromas plexiformes representam uma neoplasia frequente na neurofibromatose tipo 1 onde os neurofibromas surgem de múltiplos nervos envolvendo, também, o tecido conjuntivo e a pele raramente acometendo o cólon e o reto. A co-ocorrência de neurofibromas plexiformes, tumores neuroendócrinos, com envolvimento primário do reto, e carcinoma medular de tireoide em pacientes com neurofibromatose tipo 1 é uma condição ainda não descrita. O objetivo deste manuscrito é descrever um caso de neurofibromas plexiformes e tumores neuroendócrinos primários do reto superior, em paciente com neurofibromatose tipo 1, cujo sequenciamento genético identificou uma nova mutação no gene neurofibromatose tipo 1 e revisar a literatura sobre o tema. DESCRIÇÃO DO CASO: Mulher de 49 anos, com história familiar de neurofibromatose tipo 1 queixava-se de cólicas abdominais há seis meses. Tinha sido previamente submetida a tireoidectomia total por carcinoma medular de tireoide. Foi submetida a colonoscopia, que identificou lesão submucosa localizada no reto superior. A doente foi encaminhada para retossigmoidectomia laparoscópica, cujo estudo histopatológico do espécime cirúrgico identificou dois tumores distintos. Realizou-se painel imuno-histoquímico para confirmação histopatológica da etiologia de ambas as lesões. O resultado do painel mostrou intensa imunoexpressão da proteína S-100 da lesão superficial e de maior tamanho,e positividade para cromogranina e somatofisina da lesão mais profunda e de menores dimensões confirmando o diagnóstico de neurofibromas plexiformes retal e tumores neuroendócrinos. O índice de atividade proliferativa utilizando o anticorpo ant-Ki-67 mostrou que ambos os tumores apresentavam baixa índice mitótico (<1%). O painel genético identificou mutação no gene neurofibromatose tipo 1 (deleção, exons 2-30) ainda não descrita. A doente apresentou evolução pós-operatória sem intercorrências, permanecendo bem, sem recorrência, três anos após a cirurgia. CONCLUSÕES: A co-ocorrência de carcinoma medular de tireoide, neurofibromas plexiformes e tumores neuroendócrinos do reto em pacientes com neurofibromatose tipo 1 é uma possibilidade excepcional e ainda não descrita, cujo diagnóstico pode ser confirmado pela coloração imuno-histoquímica e painel genético.

Abducens Nerve Schwannoma: Case Report and Literature Review / Schwannoma do nervo abducente: Relato de caso e revisão da literatura

The authors describe a rare case of abducens nerve schwannoma, manifested with headache and diplopia, associated to right side cerebellar syndrome. During surgery, the authors identified that the origin of the tumor was from the abducens nerve, and the histopathological diagnosis confirmed that it was a schwannoma. A gross total tumor resection was performed, and the patient recovered from her symptoms 1 month after surgery. The authors followed the Case Report guidelines (CARE) guideline and the patient authorized the authors to publish the present case report by signing an informed consent form.

Os autores descrevem um raro caso de Schwannoma do nervo abducente, cuja manifestaçao clínica foi com cefaleia e diplopia, associadas à síndrome cerebelar hemisférica direita. Durante a cirurgia, os autores identificaram que o tumor tinha sua origem junto ao nervo abducente, e o diagnóstico histopatológico confirmou schwannoma. Realizou-se uma ressecção completa do tumor e o paciente apresentou melhora total dos sintomas em um mês após a cirurgia. Os autores seguiram as diretrizes do CARE para produzir este relato e o paciente assinou o termo de consentimento livre e esclarecido, autorizando a publicação deste caso.

Does Octreoscan add value in the differential diagnosis of parapharyngeal space lesions?

Abstract Objective: We sought to evaluate the added value of complementary functional imaging in the differential diagnosis of parapharyngeal space lesions, as well as the benefit of performing a structured evaluation of diagnostic cross-sectional examinations. Materials and Methods This was a retrospective study of 16 patients with parapharyngeal space lesions who were referred to our facility following a cross-sectional imaging study listing head and neck paraganglioma as a possible diagnosis. Each patient underwent somatostatin receptor scintigraphy with111In-pentetreotide (Octreoscan) prior to surgical resection of the lesion. In addition, the initial computed tomography (CT) or magnetic resonance imaging (MRI) scans were reviewed by two radiologists specializing in head and neck imaging, working independently, according to predefined diagnostic criteria. Results: Increased somatostatin receptor expression was observed in 14 of the 16 lesions evaluated. Histopathology of the surgical specimens showed that 11 of those 14 lesions were paragangliomas. Upon review, none of the three lesions for which there was a false-positive scintigraphy result (one intravascular meningioma and two schwannomas) were found to meet enough of the conventional imaging criteria for a diagnosis of paraganglioma. Conclusion: Structured analysis of imaging data increases the accuracy of the diagnosis of indeterminate parapharyngeal space lesions. Because of its high sensitivity, functional evaluation by somatostatin receptor scintigraphy should be considered a useful complementary tool for the detection of head and neck paraganglioma, provided that its limited specificity is taken into account.

Case for diagnosis. Infraorbital schwannoma

Abstract We report a 40-year-old man, with an unremarkable personal and family history, who presented for evaluation of an asymptomatic papule located on his right cheek. Histopathology revealed an encapsulated neoplasm within the dermis; composed by narrow, elongated, and wavy cells with an ill-defined cytoplasm, dense chromatin and tapered ends interspersed with collagen fibers. Pathologic findings were consistent with tissue of Antoni B pattern. The diagnosis was an infraorbital schwannoma. The incidental finding of rare tumors like this, should make clinicians consider a greater spectrum of differential diagnoses for a unilateral skin-colored papule on the cheek of patients.