Image features and clinical analysis of retroperitoneal pelvic schwannoma: a case report.

BACKGROUND: Schwannomas are benign usually encapsulated nerve sheath tumors derived from the Schwann cells, and affecting single or multiple nerves. The tumors commonly arise from the cranial nerves as acoustic neurinomas but they are extremely rare in the pelvis and the retroperitoneal area. Retroperitoneal pelvic schwannomas often present with non-specific symptoms leading to misdiagnosis and prolonged morbidity. CASE PRESENTATION: We report the case of a 59-year-old woman presenting with a feeling of heaviness in the lower abdomen who was found to have a retroperitoneal pelvic schwannoma originating from the right femoral nerve. She had a history of two resections of peripheral schwannomas at four different sites of limbs. After conducting magnetic resonance imaging, this pelvic schwannoma was misdiagnosed as a gynecological malignancy. The tumor was successfully removed by laparoscopic surgery. Pathological analysis of the mass revealed a benign schwannoma of the femoral nerve sheath with demonstrating strong, diffuse positivity for S-100 protein. CONCLUSIONS: Although retroperitoneal pelvic schwannoma is rare, it should be considered in the differential diagnosis of pelvic masses, especially in patients with a history of neurogenic mass or the presence of neurogenic mass elsewhere.

Management of a giant adrenal schwannoma.

In this case report, we present a man in his 60s who presented with an incidentally discovered right adrenal mass, which turned out to be an adrenal schwannoma. This is a very rare tumour that originates from Schwann cells and involves the peripheral nerves. The tumour was removed by open adrenalectomy, and this 15-cm adrenal schwannoma is one of the largest reported in the literature, with none >16 cm having ever been reported. This case highlights the importance of keeping an open mind about the cause of an incidentally discovered adrenal mass, which is an increasingly common way for adrenal tumours to present given the increased access to cross-sectional imaging. As well as presenting the case and the pathological basis behind adrenal schwannomas, we include a review of the literature and a general discussion about incidentally discovered adrenal masses.

NF2-Related Schwannomatosis (NF2): Molecular Insights and Therapeutic Avenues.

NF2-related schwannomatosis (NF2) is a genetic syndrome characterized by the growth of benign tumors in the nervous system, particularly bilateral vestibular schwannomas, meningiomas, and ependymomas. This review consolidates the current knowledge on NF2 syndrome, emphasizing the molecular pathology associated with the mutations in the gene of the same name, the NF2 gene, and the subsequent dysfunction of its product, the Merlin protein. Merlin, a tumor suppressor, integrates multiple signaling pathways that regulate cell contact, proliferation, and motility, thereby influencing tumor growth. The loss of Merlin disrupts these pathways, leading to tumorigenesis. We discuss the roles of another two proteins potentially associated with NF2 deficiency as well as Merlin: Yes-associated protein 1 (YAP), which may promote tumor growth, and Raf kinase inhibitory protein (RKIP), which appears to suppress tumor development. Additionally, this review discusses the efficacy of various treatments, such as molecular therapies that target specific pathways or inhibit neomorphic protein-protein interaction caused by NF2 deficiency. This overview not only expands on the fundamental understanding of NF2 pathophysiology but also explores the potential of novel therapeutic targets that affect the clinical approach to NF2 syndrome.

Combined open maxillectomy and endoscopic endonasal resection of a giant V2 trigeminal schwannoma.

BACKGROUND: Trigeminal schwannoma is a rare type of tumor that arises from the Schwann cells of the trigeminal nerve. METHOD: We present a case of a patient with a giant V2 trigeminal schwannoma with painful swelling in the left maxilla. A complete resection using a combined open maxillectomy and endoscopic endonasal approach was performed. CONCLUSION: This case highlights the importance of a multidisciplinary approach to perform a combined open and endoscopic approach for safe resection while preserving adequate speech and swallowing.

Esophageal schwannoma mimicking non-functional parathyroid adenoma on 99mTc-sestamibi imaging: a case report.

Technetium-99m sestamibi single-photon emission computed tomography/computed tomography (99mTc-sestamibi SPECT/CT) is a mainstay of the pre-operative localization of parathyroid lesions. We report here the case of a 30 year-old woman with a fortuitously discovered 2 cm cervical mass for which a parathyroid origin was originally suspected due to its retro-thyroidal localization and a personal history of nephrolithiasis. Normal serum calcium and parathyroid hormone (PTH) levels excluded primary hyperparathyroidism, raising suspicion of a non-functional parathyroid adenoma, and SPECT/CT imaging showed that the mass was 99mTc-sestamibi-avid. Fine-needle aspiration (FNA) was performed; cytology was non-diagnostic but the needle washout was negative for thyroglobulin, calcitonin and PTH, arguing against a thyroidal or parathyroidal origin of the mass. Core needle biopsy revealed a schwannoma, ostensibly originating from the recurrent laryngeal nerve; upon surgical resection, it was finally found to arise from the esophageal submucosa. This case illustrates the fact that endocrinologists, radiologists, nuclear medicine, head and neck, and other specialists investigating patients with cervical masses should be aware that schwannomas need to be considered in the differential diagnosis of focal 99mTc-sestamibi uptake in the neck region.

Microsurgical resection of a samii type D jugular foramen schwannoma via the carotid triangle without removal of bony structure: how I do it.

BACKGROUND: Samii Type-D jugular foramen schwannomas (JFSs) are the most challenging for neurosurgeons because of anatomical complexity. Various neurosurgical approaches have been described to gain access to JF. METHODS: We present a female with incidental diagnosis of the Type-D JFS. Complete radical resection was achieved via the carotid triangle approach without any bony structure removal. And the patient was discharged asymptomatic and without new-developed neurological deficits. CONCLUSIONS: The carotid triangle is a secure and appropriate approach for some cases of selected Type-D JFSs. However, the specific indications of this approach should be further explored and investigated.

[Retroperitoneal schwannoma mimicking colorectal cancer metastases: a false positive result report.] / Schwannoma retroperitoneal simulando metástasis de cáncer colorrectal: reporte de un resultado falso positivo.

Introduction: schwannomas are benign and common soft tissue tumors. They are usually asymptomatic and are discovered for other reasons. Materials: we present the case of an 82-year-old male patient with a recent diagnosis of moderately differentiated adenocarcinoma of the colon and a hypermetabolic periaortic nodule as an incidental finding. Results: percutaneous biopsy of the periaortic nodule confirmed the diagnosis of schwannoma. At one year of follow-up, growth of the schwannoma has been demonstrated. There are no signs of progression of his oncological disease. Conclusions: schwannomas are benign tumors, rarely found in the retroperitoneum and can be sources of false-positive positron emission tomography results.

Introducción: los schwannomas son tumores benignos y frecuentes de las partes blandas. Habitualmente son asintomáticos y son descubiertos por otros motivos. Materiales y métodos: presentamos el caso de un paciente masculino de 82 años con diagnóstico reciente de adenocarcinoma de colon moderadamente diferenciado y con un nódulo periaórtico hipermetabólico como hallazgo incidental. Resultados: la biopsia percutánea del nódulo periaórtico confirmó el diagnóstico de schwannoma. Al año de seguimiento, se ha demostrado crecimiento del schwannoma. No hay signos de progresión de su enfermedad oncológica. Conclusión: los schwannomas son tumores benignos, infrecuentes en el retroperitoneo y pueden ser fuentes de resultados falsos positivos en tomografía por emisión de positrones.

Schwannoma diagnosed by endobronchial ultrasound-guided intranodal forceps biopsy using standard-sized biopsy forceps: A case report.

Schwannomas are classified as neurogenic tumors and are the most frequent nerve sheath tumors in the paravertebral mediastinum. Recently, the addition of endobronchial ultrasound-guided intranodal forceps biopsy (EBUS-IFB) using standard-sized biopsy forceps (SBFs) to endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for metastatic lymph nodes in lung cancer patients reportedly improved the quality and quantity of the obtained specimens without significant complications. However, reports on the usefulness of this technique for benign diseases remain scarce. Here we report a case of schwannoma in the middle mediastinum, which was diagnosed by EBUS-IFB using SBFs, despite inadequate specimens obtained via EBUS-TBNA. An 80-year-old woman presented with dyspnea and a 5-cm sized middle mediastinal tumor. EBUS-TBNA and EBUS-IFB using SBFs were performed for histological diagnosis. No complications were associated with the bronchoscopy procedure, and schwannoma was solely diagnosed using the EBUS-IFB specimens. EBUS-IFB using SBFs is potentially useful for diagnosing benign diseases, including schwannomas, which are often difficult to diagnose with EBUS-TBNA.

Malignant melanotic schwannoma of the cervical spinal cord: a case report.

Spinal cord malignant melanotic schwannoma (MMNST) is a rare central nervous system tumor that originates from the spinal cord or spinal myelin sheath cells and can produce melanin. This type of tumor is usually highly aggressive and malignant, with a poor prognosis. The clinical manifestations of spinal cord MMNST are mainly pain, paresthesia, muscle weakness, muscle atrophy, etc., and symptoms of spinal cord compression, such as intestinal and bladder dysfunction, paraplegia, etc. Early detection of tumor lesions can facilitate tumor removal, improve patients' quality of life, and prolong patients' survival. In this case report, a 27-year-old young woman was diagnosed with MMNST of the cervical spinal cord due to weakness of her limbs in our hospital, and underwent surgical resection. The patient's limbs returned to normal after surgery. It is worth mentioning that the patient visited our hospital 7 months ago for "right upper limb pain for 3 days" and was diagnosed with a cervical spine space-occupying lesion at the same position this time, but the pathology report was "hemosiderosis". The patient's limbs returned to normal after surgery. It is worth mentioning that the patient visited our hospital 7 months ago for "right upper limb pain for 3 days" and was diagnosed with a cervical spine space-occupying lesion at the same position this time, but the pathology report was "hemosiderosis". This case report aims to raise awareness of the problem of spinal cord MMNST and contribute to greater knowledge of this rare tumor. This case report aims to raise awareness of the problem of spinal cord MMNST and contribute to greater knowledge of this rare tumor.

Tumors of the nervous system and hearing loss: Beyond vestibular schwannomas.

Hearing loss is a common side effect of many tumor treatments. However, hearing loss can also occur as a direct result of certain tumors of the nervous system, the most common of which are the vestibular schwannomas (VS). These tumors arise from Schwann cells of the vestibulocochlear nerve and their main cause is the loss of function of NF2, with 95 % of cases being sporadic and 5 % being part of the rare neurofibromatosis type 2 (NF2)-related Schwannomatosis. Genetic variations in NF2 do not fully explain the clinical heterogeneity of VS, and interactions between Schwann cells and their microenvironment appear to be critical for tumor development. Preclinical in vitro and in vivo models of VS are needed to develop prognostic biomarkers and targeted therapies. In addition to VS, other tumors can affect hearing. Meningiomas and other masses in the cerebellopontine angle can compress the vestibulocochlear nerve due to their anatomic proximity. Gliomas can disrupt several neurological functions, including hearing; in fact, glioblastoma multiforme, the most aggressive subtype, may exhibit early symptoms of auditory alterations. Besides, treatments for high-grade tumors, including chemotherapy or radiotherapy, as well as incomplete resections, can induce long-term auditory dysfunction. Because hearing loss can have an irreversible and dramatic impact on quality of life, it should be considered in the clinical management plan of patients with tumors, and monitored throughout the course of the disease.

Peripheral nerve tumors.

The chapter is focused on the neoplastic peripheral nerve lesions, which primarily involve "cranial and paraspinal nerves," as outlined in the CNS volume (WHO_Classification_of_Tumours_Editorial_Board, 2021). These include classic peripheral nerve sheath tumors such as schwannoma, neurofibroma, intraneural perineurioma, and malignant peripheral nerve sheath tumors, with their variants as well as new and more precisely defined entities, including hybrid nerve sheath tumors and malignant melanotic nerve sheath tumor (previously melanotic schwannoma).

Incidental Finding of an Asymptomatic Jejunal Schwannoma: A Rare Case Report and Review of Literature.

BACKGROUND Schwannomas are tumors that arise from Schwann cells that surround and support nerve cells. Most common sites for presentations are head, neck, and extremities. Schwannomas of gastrointestinal tract are rare, slow-growing tumors, usually benign, arising from gastrointestinal tract's neural plexus. They are histologically distinguishable from conventional schwannomas that arise in soft tissue or the central nervous system. Preoperative diagnosis of gastrointestinal schwannoma is challenging, requiring immunohistological confirmation of the nature of the tumor. Here, we report a case of 57-year-old woman with an incidental finding of an asymptomatic submucosal jejunal schwannoma. CASE REPORT A 57-year-old woman with a medical history of hematological disorder underwent a contrast abdominal computed tomography as part of medical follow-up. The imaging revealed the presence of a jejunal mass. The patient underwent laparoscopic surgical resection of the lesion, followed by side-to-side jejuno-jejunal anastomosis with 4-cm clear surgical margins. The final pathologic study revealed the presence of jejunal schwannoma, as tested positive for S-100 protein. The patient was discharged home on the fourth postoperative day, having an uneventful recovery. CONCLUSIONS Jejunal schwannoma are usually benign and asymptomatic, and they are often discovered incidentally during diagnostic tests for other conditions; therefore, it should be included in the differential diagnosis of gastrointestinal tumors. Surgical treatment appears to be necessary to achieve a definitive diagnosis through a biopsy of the tumor tissue. Benign jejunal schwannomas have a good prognosis.

The advent of the first electric driven EUS-guided 17 gauge core needle biopsy - A pilot study on subepithelial lesions.

BACKGROUND AND AIMS: This pilot study aimed to evaluate safety and tissue sampling from subepithelial lesions (SEL) in the upper gastrointestinal tract with a novel electric motor driven endoscopic ultrasonography (EUS)-guided 17-gauge (G) size core needle biopsy (CNB) instrument. METHODS: An investigator-led prospective open label, performance and safety control study, including seven patients (female n = 4, median 71 y, range 28-75) with a determined SEL (median size 30 mm, range 17-150 mm) in the upper digestive tract (stomach n = 6, duodenum n = 1) were eligible and later followed up 14 days after index procedure. All investigations were completed according to protocol with three FNB 22-G passes with four fanning strokes and two EndoDrill® 17-G passes with three fanning strokes. RESULTS: Quality of samples as 'visible pieces' (>5 mm): FNB (n = 5/7) (fragmented/blood imbibed n = 1, poor tissue quantity n = 1) compared with 17-G CNB (n = 7/7). Histological result which led to final diagnosis (leiomyoma n = 2, adenocarcinoma n = 1, schwannoma n = 1, neuroendocrine tumour n = 1, desmoid tumour n = 1 and gastrointestinal stromal tumour (GIST) n = 1) could be obtained with the 17-G CNB instrument in all seven patients. FNB technique reached correct diagnosis in six patients. No serious adverse event were recorded. CONCLUSIONS: By using an electric driven 17-G biopsy device, a true cylinder of core tissue can be obtained in one single puncture from the area of interest reducing the need for a second sampling. The absolute benefit of EUS-guided CNB is that the sample can be handled and histologically prepared in the same manner as standard percutaneous core needle sample, e.g., breast and prostate cancer.

Sporadic Malignant Triton Tumor of Shoulder: a Case Report.

Background: Malignant triton tumors (MTT) are subtype of malignant peripheral nerve sheath tumor (MPNST) which develop from Schwan cells of peripheral nerves or within neurofibromas, and shows rhabdomyoblastic differentiation. It is a rare soft tissue tumor with poor prognosis. Objective: We report a case of Malignant Triton Tumor (MTT) arising in the right shoulder in a 46 year old male patient presented to our Musculoskeletal Oncology Clinic at Royal Rehabilitation center at King Hussein Medical Center during June 2018. Case presentation: The patient was complaining of an 8 months long progressive right shoulder pain and swelling at the posterior lateral area of the shoulder. As accurate diagnosis is crucial in such case, investigations that included x-rays and magnetic resonance imaging (MRI) demonstrated an soft tissue tumor involving the right shoulder area leading to the differential diagnosis of aggressive soft tissue tumor which laid down the plan of an open incisional biopsy to be reported histopathological as a case of Malignant Triton Tumor which is a very rare and aggressive sarcoma originates from the peripheral nerve sheaths as it is subtype of malignant peripheral nerve sheath tumors after which excision of the entire tumor with safety margin was performed and referred for adjuvant chemotherapy. Conclusion: The treatment of choice is radical tumor excision with wide margins followed by chemotherapy and /or radiotherapy to improve the 5 years survival rates.

Clinical and radiological features of intracranial ancient schwannomas: a single-institution, retrospective analysis.

Ancient schwannoma (AS) is a subtype of schwannoma characterized by slow progression despite degenerative changes in pathology. Although it is considered a benign tumor, most previous reports have focused on extracranial AS; therefore, the clinical characteristics of intracranial AS is not clear. We included 174 patients who underwent surgery for sporadic intracranial schwannoma, and 13 patients (7.5%) were diagnosed with AS. Cysts were significantly more common in patients with AS than conventional schwannomas (92.3% vs. 44.7%, p < 0.001), as was bleeding (38.5% vs. 6.9%, p = 0.003) and calcification (15.4% vs. 1.3%, p = 0.029). The maximum tumor diameter was also larger in patients with AS (35 mm vs. 29 mm, p = 0.017). The median duration from symptom onset to surgery (7.0 vs. 12.5 months, p = 0.740) did not significantly differ between groups, nor did the probability of postoperative recurrence (p = 0.949). Intracranial AS was strongly associated with cyst formation and exhibited a benign clinical course with a lower rate of recurrence and need for salvage treatment. Extracranial AS is reportedly characterized by a slow progression through a long-term clinical course, whereas intracranial AS did not progress slowly in our study and exhibited different clinical features to those reported for extracranial AS.

[Malignant melanotic nerve sheath tumor of the posterior mediastinum]. / Tumor maligno melanocítico de la vaina neural en mediastino posterior.

Melanotic schwannoma (MS) is a rare and infrequent subtype of schwannoma characterized by cytoplasmic deposits of melanosomes (melanin). Unlike the other schwannomas, it could have malignant transformation. Due to distinctive characteristics and atypical behavior from classic schwannomas subtypes, MS were renamed and reclassified as "melanocytic malignant neural sheath tumor" in the 5th ed. of the World Health Organization's classification of central nervous system tumors in 2021. We present two cases of MS that underwent complete surgical resection.

El schwannoma melanótico (SM) es una variante rara e infrecuente caracterizada por el depósito citoplasmático de melanosomas (melanina). A diferencia de las otras variantes de schwannomas, tienen capacidad de malignización. Por poseer características y comportamiento distintos al resto de los schwannomas, fue reclasificado como "tumor maligno melanocítico de la vaina neural" en la 5ta edición de la clasificación de los tumores del sistema nervioso central de la Organización Mundial de la Salud en 2021. Presentamos dos casos de SM de ubicación mediastinal en los que se realizó una resección quirúrgica completa.