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.

Tracheal Schwannoma Presenting as Subcutaneous Emphysema and Pneumomediastinum.

Primary tracheal schwannomas are rare benign tumours. This is a case report, and therefore, no specific methods or results are applicable. We here report a case of a tracheal schwannoma in an early adolescent girl presenting with subcutaneous emphysema and symptoms of airway obstruction. Tracheal resection and reconstruction by primary anastomosis were performed. Pathology confirmed the diagnosis of tracheal schwannoma. This is an unusual life-threatening presentation of a benign rare tracheal tumour with a challenging approach to management.

Differential diagnosis of rare adrenal cellular schwannomas: A case report.

BACKGROUND: Adrenal cellular schwannomas are exceptionally rare stromal tumors that are often misdiagnosed due to the lack of specific radiological, serological, or clinical features. In this report, we describe the differential diagnosis of a rare adrenal cellular schwannoma. METHODS: A 69-year-old man with a history of persistent hypertension, chronic kidney disease, hypertensive heart disease, and cardiac insufficiency was hospitalized due to bilateral lower extremity edema lasting for 3 months. Plain computed tomography at that time revealed a space-occupying lesion in the right adrenal gland. As serum levels of catecholamines, cortisol, and adrenocorticotropic hormone were within normal ranges, the edema was attributed to the chronic kidney disease and cardiac insufficiency, and the patient was referred to our hospital for surgical treatment. Contrast-enhanced computed tomography revealed heterogeneous enhancement in the adrenal mass indicating pheochromocytoma. An irregularly shaped 5 cm mass with a complete capsule in the right adrenal gland was laparoscopically resected. The postoperative histopathological diagnosis was adrenal cellular schwannoma. RESULTS: The postoperative course was unremarkable and the tumor did not recur during 5 years of follow-up. CONCLUSION: Adrenal cellular schwannoma is a very rare tumor that is extremely difficult to preoperatively diagnose. Histological and immunohistochemical analyses are required for differential diagnosis and confirmation. Cellular schwannomas can transform into malignant peripheral nerve sheath tumors, but not often. Consequently, regular postoperative follow-up is required for such patients, especially imaging.

[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".

Intramuscular Hybrid Nerve Sheath Tumor of the Thigh: Case Report and Literature Review.

BACKGROUND/AIM: Hybrid nerve sheath tumor (HNST) is a benign peripheral nerve sheath tumor with combined features of more than one histological type, such as schwannoma, neurofibroma, and perineurioma. It remains under-recognized in routine clinical practice. Herein, we describe an unusual case of intramuscular HNST of the thigh. CASE REPORT: The patient was a 41-year-old man with no history of trauma who presented with a 3-month history of a palpable mass in the right thigh. Physical examination revealed a 4-cm, elastic hard, mobile, nontender mass. Magnetic resonance imaging exhibited a well-circumscribed intramuscular mass with low-to-intermediate signal intensity on T1-weighted sequences and higher signal intensity peripherally and lower signal intensity centrally, representing a target sign, on T2-weighted sequences. Complete surgical excision of the tumor was carried out. Microscopically, the tumor showed dual histological components of both schwannoma and neurofibroma. Immunohistochemically, the schwannomatous component was strongly and diffusely positive for S-100 protein and negative for CD34, while the neurofibromatous component contained CD34-positive fibroblasts and S-100 protein-positive Schwann cells. Epithelial membrane antigen was negative for both components. These findings were consistent with a diagnosis of HNST (hybrid schwannoma/neurofibroma). The patient had no evidence of local recurrence and no neurological deficit at the final follow-up. CONCLUSION: Although extremely rare, HNST should be included in the extended differential diagnosis of a well-circumscribed, intramuscular soft-tissue mass in the extremities, particularly in young and early middle-aged adults.

Improved sensitivity for detection of pathogenic variants in familial NF2-related schwannomatosis.

PURPOSE: To determine the impact of additional genetic screening techniques on the rate of detection of pathogenic variants leading to familial NF2-related schwannomatosis. METHODS: We conducted genetic screening of a cohort of 168 second-generation individuals meeting the clinical criteria for NF2-related schwannomatosis. In addition to the current clinical screening techniques, targeted next-generation sequencing (NGS) and multiplex ligation-dependent probe amplification analysis, we applied additional genetic screening techniques, including karyotype and RNA analysis. For characterisation of a complex structural variant, we also performed long-read sequencing analysis. RESULTS: Additional genetic analysis resulted in increased sensitivity of detection of pathogenic variants from 87% to 95% in our second-generation NF2-related schwannomatosis cohort. A number of pathogenic variants identified through extended analysis had been previously observed after NGS analysis but had been overlooked or classified as variants of uncertain significance. CONCLUSION: Our study indicates there is added value in performing additional genetic analysis for detection of pathogenic variants that are difficult to identify with current clinical genetic screening methods. In particular, RNA analysis is valuable for accurate classification of non-canonical splicing variants. Karyotype analysis and whole genome sequencing analysis are of particular value for identification of large and/or complex structural variants, with additional advantages in the use of long-read sequencing techniques.

Perspectives of adults with neurofibromatosis regarding the design of psychosocial trials: Results from an anonymous online survey.

BACKGROUND/AIMS: Individuals with neurofibromatosis, including neurofibromatosis 1 (NF1), neurofibromatosis 2 (NF2)-related schwannomatosis (SWN), and other forms of SWN, often experience disease manifestations and mental health difficulties for which psychosocial interventions may help. An anonymous online survey of adults with neurofibromatosis assessed their physical, social, and emotional well-being and preferences about psychosocial interventions to inform clinical trial design. METHODS: Neurofibromatosis clinical researchers and patient representatives from the Response Evaluation in Neurofibromatosis and Schwannomatosis International Collaboration developed the survey. Eligibility criteria included age ≥ 18 years, self-reported diagnosis of NF1, NF2, or SWN, and ability to read and understand English. The online survey was distributed internationally by the Neurofibromatosis Registry and other neurofibromatosis foundations from June to August 2020. RESULTS: Surveys were completed by 630 adults (18-81 years of age; M = 45.5) with NF1 (78%), NF2 (14%), and SWN (8%) who were mostly White, not Hispanic/Latino, female, and from the United States. The majority (91%) reported that their neurofibromatosis symptoms had at least some impact on daily life. In the total sample, 51% endorsed a mental health diagnosis, and 27% without a diagnosis believed they had an undiagnosed mental health condition. Participants indicated that neurofibromatosis affected their emotional (44%), physical (38%), and social (35%) functioning to a high degree. Few reported ever having participated in a drug (6%) or psychosocial (7%) clinical trial, yet 68% reported they "probably" or "definitely" would want to participate in a psychosocial trial if it targeted a relevant concern. Top treatment targets were anxiety, healthier lifestyle, and daily stress. Top barriers to participating in psychosocial trials were distance to clinic, costs, and time commitment. Respondents preferred interventions delivered by clinicians via individual sessions or a combination of group and individual sessions, with limited in-person and mostly remote participation. There were no significant group differences by neurofibromatosis type in willingness to participate in psychosocial trials (p = 0.27). Regarding interest in intervention targets, adults with SWN were more likely to prefer psychosocial trials for pain support compared to those with NF1 (p < 0.001) and NF2 (p < 0.001). CONCLUSION: This study conducted the largest survey assessing physical symptoms, mental health needs, and preferences for psychosocial trials in adults with neurofibromatosis. Results indicate a high prevalence of disease manifestations, psychosocial difficulties, and untreated mental health problems in adults with neurofibromatosis and a high degree of willingness to participate in psychosocial clinical trials. Patient preferences should be considered when designing and implementing psychosocial interventions to develop the most feasible and meaningful studies.

Gene-targeted therapy for neurofibromatosis and schwannomatosis: The path to clinical trials.

Numerous successful gene-targeted therapies are arising for the treatment of a variety of rare diseases. At the same time, current treatment options for neurofibromatosis 1 and schwannomatosis are limited and do not directly address loss of gene/protein function. In addition, treatments have mostly focused on symptomatic tumors, but have failed to address multisystem involvement in these conditions. Gene-targeted therapies hold promise to address these limitations. However, despite intense interest over decades, multiple preclinical and clinical issues need to be resolved before they become a reality. The optimal approaches to gene-, mRNA-, or protein restoration and to delivery to the appropriate cell types remain elusive. Preclinical models that recapitulate manifestations of neurofibromatosis 1 and schwannomatosis need to be refined. The development of validated assays for measuring neurofibromin and merlin activity in animal and human tissues will be critical for early-stage trials, as will the selection of appropriate patients, based on their individual genotypes and risk/benefit balance. Once the safety of gene-targeted therapy for symptomatic tumors has been established, the possibility of addressing a wide range of symptoms, including non-tumor manifestations, should be explored. As preclinical efforts are underway, it will be essential to educate both clinicians and those affected by neurofibromatosis 1/schwannomatosis about the risks and benefits of gene-targeted therapy for these conditions.

Gastric schwannoma: A retrospective analysis of clinical characteristics, treatments, and outcomes.

BACKGROUND: This study aimed to investigate the clinical characteristics, treatment options, and prognosis of patients with gastric schwannoma (GS). METHODS: Patients who were pathologically diagnosed with GS between April 2011 and October 2022 were enrolled. The data of clinical characteristics, pathological features, treatment options, and clinical outcomes were collected and compared between GS patients who underwent endoscopic resection (ER) and surgical resection (SR). RESULTS: Of the 32 cases, 23 underwent SR and nine underwent ER. The median tumor size was significantly smaller in ER group than in SR group (12.0 vs. 40.0 mm, P < 0.001), while patients in SR group were older than those in ER group (54.5 ± 10.6 vs. 45.3 ± 10.9 years, P = 0.036). Moreover, tumors in ER group were more likely to exhibit an intraluminal pattern (100% vs. 26.1%, P < 0.001). Patients in ER group had significantly lower hospitalization cost (25859.2 ± 8623.9 vs. 44953.0 ± 13083.8 RMB, P = 0.011) than those in SR group. No differences were found between the two groups in terms of R0 resection rate, operative time, estimated blood loss, adverse events, and recurrence rate. All patients were followed up for 4-96 months (mean: 35 months; median: 23 months), during which no evidence of recurrence or metastasis was observed. CONCLUSIONS: Both ER and SR are safe and effective treatment modalities for the management of GS, with ER being associated with lower medical costs compared to SR. The majority of GS are benign and do not recur, with little possibility of malignant transformation.

Hybrid Schwannoma-Perineurioma of the Orbit.

A 52-year-old woman presented with a 6-month history of progressive right proptosis associated with intermittent right retrobulbar and facial pain. MRI revealed a heterogeneously enhancing, well-circumscribed, ovoid, soft tissue mass in the intraconal space near the right orbital apex displacing the optic nerve medially. Excisional biopsy established the diagnosis of a schwannoma-perineurioma hybrid peripheral nerve sheath tumor (HPNST). This case represents only the second reported occurrence, to our knowledge, of an orbital schwannoma-perineurioma HPNST.

Plexiform Schwannoma of the Eyelid.

Plexiform schwannoma of the lacrimal gland of the palpebral lobe has not been previously described. This 41-year-old male presented with a 2-year history of a left upper eyelid mass and associated regional irritation. MRI of the head and orbits confirmed a left superolateral multinodular mass centered on the palpebral lobe of the left lacrimal gland. Excision revealed a schwannoma of the plexiform subtype.

Giant benign intrathoracic schwannoma: a decade-long progression towards fatality.

BACKGROUND: Intrathoracic neurogenic tumors arise from sympathetic nerve trunks and intercostal nerves; more than 90% are benign. Schwannomas are the most common histological variety, but fatalities due to giant schwannomas are rare. CASE PRESENTATION: We report a case of a 65-year-old woman who presented with chest pain and cough. Computed tomography (CT) revealed a large left chest wall mass of 130-mm in size, and the patient was referred to our department. Tumor biopsy was performed under local anesthesia, and a diagnosis of schwannoma was made. Ten years previously, a 30-mm tumor had been noted in the left third intercostal space by a previous doctor, but follow-up had been interrupted owing to depressive disorder. Although we planned to perform intercostal artery embolization followed by chest wall tumor resection, the patient did not consent to surgery due to uncontrolled depression. After four months, she developed respiratory failure caused by compression due to an enlarged tumor and died. Autopsy also revealed a benign schwannoma with no malignant findings. CONCLUSIONS: Although schwannomas are benign tumors, there are some very rare cases in which they can become huge and life-threatening. Therefore, a benign tumor should not be neglected, and if surgery is not possible at the time of diagnosis, a regular follow up is necessary, in order not to miss the right timing for surgery.

Eyelid Schwannoma. A Case Report.

In this case report, we describe a 53-year-old woman who presented with a slow-growing lower lid mass in her right eye. On gross examination, a remarkable lower lid bulging was noted. On palpation, a subcutaneous oval-shaped mass with a firm consistency, measuring about 2cm, was noted. The uncorrected visual acuities of the patient were 20/20 (by Snellen chart) bilaterally, and the examinations of the anterior and posterior segments of both eyes were unremarkable. On the orbital Computed Tomography scan of the patient, a solitary and homogenous solid globular mass with the same density of the brain tissue was obvious. The patient underwent surgical excision. Microscopic assessment of the lesion revealed a biphasic hypercellular area (Antoni A) and myxoid hypocellular areas (Antoni B), containing slender cells with tapered ends, interspersed with collagen fibers, consistent with a diagnosis of schwannoma. In addition, some foci of nuclear palisading around the fibrillary process (Verocay bodies) could frequently be found throughout the highly cellular regions. Schwannomas rarely occur in the eyelids, but have clinical and paraclinical indicators which indicate the probable diagnosis. In conclusion, we suggest that eyelid schwannoma be considered as an element of the differential diagnoses list for subcutaneous lesions of the eyelid.

Spinal Schwannomas; Classification, Management And Outcomes.

Schwannomas are benign tumours of the peripheral nerve sheath. When they occur in spine, they are most commonly found in intradural-extramedullary location. Surgery is the mainstay of treatment. Radiation has a limited role in the management of residual or recurrent lesions not suitable for surgery. Here we discuss the existing literature on the outcomes of spinal schwannoma after surgery.

Subcutaneous Nasal Schwannoma in a Pediatric Patient: A Rare Case Report with Emphasis on Histopathology's Role in Differential Diagnosis.

BACKGROUND Schwannomas are rare and benign tumors of the nerve sheath, composed of Schwann cells, and they are extremely rare in the nasal area. Here, we report a case that presented to our clinic as a growing nasal mass and was found to be a unilateral subcutaneous schwannoma. There have been a few previous cases reported of such patients having nasal obstruction, epistaxis, or other symptoms, but our patient did not. We stress the importance of considering schwannoma in the differential diagnosis of nasal masses, even in pediatric patients, and the role of histopathology differentiating it from other diagnoses such as neurofibroma. CASE REPORT Our patient was a 9-year-old girl with a painless nasal swelling on the nasal bridge that she first noticed 2 years ago, which started growing gradually and began to become firm. She was otherwise asymptomatic and had no relevant family history. Histopathology revealed an encapsulated spindle cell tumor with both hypo- and hyper-cellular areas, and immunohistochemistry showed that the tumor was strongly positive for S-100 and negative for both desmin and CD34, with blood vessels marking. A final diagnosis of schwannoma was made. CONCLUSIONS We presented a case of nasal septal schwannoma, emphasizing the importance of considering schwannoma in the differential diagnosis of nasal masses, and the role of histopathology to rule out other possible diagnoses.

Maxillary gingival neurolemmoma: a case report and literature review.

OBJECTIVE: To explore and summarize the clinical features, differential diagnosis and treatment of the oral maxillofacial schwandoma. CASE PRESENTATION: This is a report of a case of a 46-year-old female patients with neurolemmoma in the maxillary gingiva. The clinical features, pathological features, differential diagnosis and treatment were analyzed. Literature review was conducted in search of domestic and overseas journal full-text database from 1986 ~ 2017. 39 reports on the oral and maxillofacial Neurolemmoma from 1986 to 2017 in the database of China hospital knowledge database and the PubMed database, there were 405 patients. There were 23 cases of gingival mucosa, 17 in foreign literature and only 6 in the domestic literature. CONCLUSIONS: The incidence of gingival Neurolemmoma is extremely low, the predilection age is similar to other parts, it is middle-aged and young, and there is no obvious gender tendency. About 25-45% of schwannomas are found in the head and neck, and rarely in the mouth (only 1%). The most common internal location of the mouth is the tongue, followed by the floor of the mouth, buccal mucosa, palate, gums, and lips. Schwannomas are slow-growing benign tumors that are rare in the gums. Gingival schwannoma is usually a single occurrence, and the clinical manifestations are mostly painless gum mass, tooth loosening and displacement, without peripheral bone changes and regional lymph node metastasis. It is difficult to diagnose this tumor according to clinical manifestations, and pathological diagnosis is still the basis for the diagnosis of gingival schwannoma. So far, surgical resection is the preferred treatment for this disease, and the prognosis is good.

Schwannomas Mimicking Leptomeningeal Spread in the Setting of Breast Cancer: A Case Report.

BACKGROUND: Breast cancer is currently the most diagnosed cancer globally. For patients who complete breast cancer treatment, developing a survivorship plan is important, including serial history, physical examinations, and annual mammograms to look for recurrence and metastasis. CASE REPORT: This is a case report of a 76-year-old female with a history of recurrent breast cancer who presented with lower-back pain and found to have MRI findings initially concerning for intradural extramedullary metastatic disease. Biopsy was later found to be consistent with benign spinal schwannomas. CONCLUSION: We present a unique case of spinal masses in the setting of breast cancer initially concerning for leptomeningeal spread, later found to have benign schwannomas that mimicked leptomeningeal spread on imaging. To our knowledge, this is the first reported case of schwannomas mimicking leptomeningeal spread in a patient with a history of recurrent breast cancer. After metastasis is excluded, schwannomas should be considered in the differential of benign spinal lesions.