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.

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).

[Analysis of clinical manifestations and imaging features of facial nerve schwannomas].

Objective:To explore the clinical manifestations and imaging characteristics, and to clarify the imaging value in the diagnosis of facial nerve schwannomas. Methods:Retrospectively analyze the data of 23 patients with facial nerve schwannomas confirmed by surgery and pathology in the Department of Otorhinolaryngology of the First Affiliated Hospital of the Air Force Military Medical University from September 2020 to September 2022, including 8 males and 15 females, aged 18-66 years old. Summarize and analyze their clinical symptoms, specialized examinations, and imaging findings. Results:The clinical manifestations were facial nerve paralysis in 15 cases（2 cases of HB Ⅳ, 6 cases of HB Ⅴ, 7 cases of HB Ⅵ）, hearing loss in 14 cases（5 cases of conductive deafness, 2 cases of mixed deafness, and 7 cases of severe sensorineural hearing loss）, 8 cases tinnitus, 7 cases ear pain, 4 cases dizziness, 4 cases headache, 2 cases ear pus, and parotid gland tumors in 6 cases presenting as local masses. Endoscopic examination revealed 8 cases of external ear canal tumors and 3 cases of intratympanic tumors. Combining temporal bone HRCT, MRI enhanced scanning, and CPR imaging techniques, 1 case involved the internal auditory canal segment, 2 cases in the tympanic segment, 6 cases in the parotid gland area. A total of 14 cases involved two or more segments of the internal auditory canal segment, the labyrinthine segment, geniculate ganglion, the tympanic segment, and the mastoid segment. When the tumors were large, adjacent structures were involved. It was found that 8 cases invaded the external auditory canal and tympanic cavity, ossicles were displaced or bony destruction; 3 cases invaded the jugular foramen area, and 1 case grew to the middle cranial fossa region with temporal lobe brain parenchymal compression. Conclusion:The clinical manifestations of facial nerve schwannomas are diverse. The combination of various imaging techniques will be conducive to topical and qualitative diagnosis and provide an important basis for treatment strategies.

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.

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.

Surgical management of large lower cranial nerves schwannomas: long term results of a less aggressive resection strategy.

In an effort to reduce the high morbidity and life-threatening complications after radical resection in large schwannoma surgery, alternative strategies of nontotal resections have emerged. To evaluate the long term clinical and oncological outcome after lower cranial nerves (LCN) schwannoma surgery operated on with a cranial nerve-sparing technique. Single center retrospective cohort study of 8 consecutive patients harboring LCN schwannomas operated on between March 2005 and October 2021. The mean LCN schwannoma diameter was 33 mm (range 26-51). Seven patients (87,5%) underwent a modified retrosigmoid approach. Three patients underwent gross total resection (37,5%), 3 had received neartotal resection (mean tumor residue 0,25 cc) and subtotal resection in 2 patients who presented with an extracranial extension of the tumor (mean tumor residue 2,44 cc). Both patients had received upfront additional GKRS. The three patients who presented with preoperative CN IX & X injuries recovered within 6 months after surgery. All of the five patients freed from any preoperative CNs IX & X symptoms experienced transient (80%) or definitive (one patient) disturbances after surgery. They all improved within 6 months but one who required long term gastrostomy feeding tube. This patient harbored a schwannoma originating from the glossopharyngeal nerve, which could not be anatomically preserved during surgery. Tumor control was achieved in 100% of cases with a mean follow-up of 91 months. LCN schwannomas could be surgically removed through a less aggressive non-radical resection strategy with acceptable functional results and excellent tumor control.

Cauda equina neuroendocrine tumor: a report of three cases and review of the literature with focus on differential diagnosis and postoperative management.

INTRODUCTION: Cauda equina neuroendocrine tumors (CENETs), previously described as cauda equina paragangliomas (PGLs) are rare and well-vascularized benign entities which can be often misdiagnosed with other intradural tumors more common in this anatomical site, such as ependymomas and neurinomas. We describe three cases of CENETs observed at our institution with particular focus on differential diagnosis and postoperative management. Since the lack of guidelines, we performed a literature review to identify factors that can predict recurrence and influence postoperative decision making. CASE REPORT AND LITERATURE REVIEW: We report on three patients, two of them presenting with a clinical history of lower back pain and sciatica. In all cases magnetic resonance imaging (MRI) of the lumbosacral spine with and without Gd-DTPA revealed an intradural lesion with strong contrast enhancement, first described as atypical ependymoma or schwannoma. A complete tumor resection was achieved in all cases, the histopathological diagnosis classified the tumors as CENETs. In our literature review, a total of 688 articles were screened and 162 patients were included. Patients demographic data, clinical symptoms, resection and recurrence were recorded. DISCUSSION: Differential diagnosis between CENETs and other more common tumors affecting cauda equina region, such as ependymomas or schwannomas (neurinomas), is still very challenging. Due to the lack of specific clinical or radiological characteristics, a correct preoperative diagnosis is almost impossible. With this paper we want to point out that CENETs must be considered in the differential diagnosis, most of all in case of entities with atypical radiological features. According to the literature, tumor recurrence after gross total resection is unlikely, while a long-term follow-up is recommended in case of subtotal resection or local aggressive behavior.

[Efficacy analysis of 23 cases of parapharyngeal space tumors removed by oral approach assisted by plasma and high-definition endoscopic system].

Objective:To explore the selection, efficacy and application of indications for parapharyngeal space tumor resection assisted by plasma and HD endoscopic system through oral approach. Methods:The clinical data of 23 patients with parapharyngeal space tumor resection assisted by plasma and HD endoscopic system were retrospectively analyzed in Department of Otolaryngology Head and Neck Surgery, the First Affiliated Hospital of Bengbu Medical University from January 2013 to June 2023. All cases were examined by high-resolution CT and MRI before operation, and some cases were examined by CTA or DSA. During the operation, the high definition nasal endoscopic recording system was assisted, and low temperature plasma knife was used in some cases. The follow-up time was from 3 to 115 months, and the median follow-up time was 45 months. Results:There were no deaths in this group. All patients had complete tumor resection. The maximum tumor diameter was as follows: （5.20±1.00） cm, the operation time was（128.70±46.67） min, and the average blood loss was（80.87±32.74） mL. One case of vascular smooth muscle tumor had more bleeding during the operation and was assisted by tracheotomy after operation. One case of nourishing vascular bleeding after operation of giant Schwannoma was investigated and hemostasis + external carotid artery ligation. Bleeding in the remaining cases was below 120 mL. Postoperative pathologies were all benign tumors, including 11 pleomorphic adenoma, 4 schwannoma, 2 base cell adenoma, 1 epidermoid cyst, 1 lymphatic cyst with infection, 1 angiomyoma, 1 solitary fibroma, 1 salivary gland cyst, and 1 tendon giant cell tumor. All patients were followed up. One patient originating from vagal schwannoma had 2-month vocal cord paralysis and 1 recurrence（recurrence of the skull base of schwannoma）. Conclusion:Oral approach assisted by plasma and high-definition endoscopic system is suitable for partial selective resection of benign tumors in parapharyngeal space, which has the advantages of less trauma and rapid recovery. When the tumor is blood-rich, suspected to be malignant, the top of the tumor is deep into the cranial base nerve canal,located outside the internal carotid artery, and larger than 6.0 cm considering pleomorphic adenoma, it is recommended to conduct an external open or auxiliary cervical small incision approach.

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.

[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.

Preservation of cranial nerve function in large and giant trigeminal schwannoma resection: a case series.

BACKGROUND: Trigeminal schwannomas (TSs) are intracranial tumors that can cause significant brainstem compression. TS resection can be challenging because of the risk of new neurologic and cranial nerve deficits, especially with large (≥ 3 cm) or giant (≥ 4 cm) TSs. As prior surgical series include TSs of all sizes, we herein present our clinical experience treating large and giant TSs via microsurgical resection. METHODS: This was a retrospective, single-surgeon case series of adult patients with large or giant TSs treated with microsurgery in 2012-2023. RESULTS: Seven patients underwent microsurgical resection for TSs (1 large, 6 giant; 4 males; mean age 39 ± 14 years). Tumors were classified as type M (middle fossa in the interdural space; 1 case, 14%), type ME (middle fossa with extracranial extension; 3 cases, 43%), type MP (middle and posterior fossae; 2 cases, 29%), or type MPE (middle/posterior fossae and extracranial space; 1 case, 14%). Six patients were treated with a frontotemporal approach (combined with transmastoid craniotomy in the same sitting in one patient and a delayed transmaxillary approach in another), and one patient was treated using an orbitofrontotemporal approach. Gross total resection was achieved in 5 cases (2 near-total resections). Five patients had preoperative facial numbness, and 6 had immediate postoperative facial numbness, including two with worsened or new symptoms. Two patients (28%) demonstrated new non-trigeminal cranial nerve deficits over mean follow-up of 22 months. Overall, 80% of patients with preoperative facial numbness and 83% with facial numbness at any point experienced improvement or resolution during their postoperative course. All patients with preoperative or new postoperative non-trigeminal tumor-related cranial nerve deficits (4/4) experienced improvement or resolution on follow-up. One patient experienced tumor recurrence that has been managed conservatively. CONCLUSIONS: Microsurgical resection of large or giant TSs can be performed with low morbidity and excellent long-term cranial nerve function.

Extracranial Hypoglossal Schwannoma: Case Report and Literature Review.

BACKGROUND: Schwannomas are solitary neurogenic tumors originating from the myelin sheath of peripheral nerves. Extracranial hypoglossal schwannomas comprise <5% of all head and neck schwannomas and can mimic submandibular salivary gland tumors. CASE REPORT: We report the diagnostic imaging, surgical treatment, and histopathological findings of a rare case of extracranial schwannoma of the hypoglossal nerve in a 73-year-old female, presented with an asymptomatic swelling in the left submandibular region that had been persisted for approximately three years. CONCLUSION: Accurate diagnosis of this rare clinical entity requires comprehensive diagnostics. The optimal therapeutic strategy is nerve-sparing surgical excision, although it can be challenging.

Unilateral Multifocal Inner Ear and Internal Auditory Canal or Cerebellopontine Angle Cochleovestibular Schwannomas-Genetic Analysis and Management by Surgical Resection and Cochlear Implantation.

OBJECTIVE: To describe the genetic characteristics and the management of two very rare cases of unilateral multifocal inner ear and internal auditory canal or cerebellopontine angle cochleovestibular schwannomas not being associated to full neurofibromatosis type 2-related schwannomatosis. PATIENTS: In a 29-year-old man and a 55-year-old woman with single-sided deafness multifocal unilateral cochleovestibular schwannomas were surgically resected, and hearing was rehabilitated with a cochlear implant (CI). Unaffected tissue was analyzed using next generation sequencing of the NF2 gene. Tumor tissue was analyzed using a 340-parallel sequencing gene panel. MAIN OUTCOME MEASURES: Mutations in the NF2 gene, word recognition score for monosyllables at 65 dB SPL (WRS 65 ) with CI. RESULTS: No disease-causing mutation was detected in the examined sequences in blood leucokytes. All tumor samples revealed, among others, somatic pathogenic NF2 mutations. While the anatomically separate tumors in case 1 were likely molecular identical, the tumors in case 2 showed different genetic patterns. WRS 65 was 55% at 6 years of follow-up and 60% at 4.5 years of follow-up, respectively. CONCLUSIONS: The occurrence of multifocal unilateral cochleovestibular schwannomas without pathogenic variants in NF2 in non-affected blood leucocytes can be associated with mosaic NF2 -related schwannomatosis (case 1), or with likely sporadic mutations (case 2) and may be overlooked due to their extreme rarity. Although challenging, successful hearing rehabilitation could be achieved through surgical resection of the tumors and cochlear implantation.

Intraoperative visualization of cranial nerve schwannomas using second-window indocyanine green: A case series.

BACKGROUND: Second Window Indocyanine Green (SWIG) is a novel intraoperative imaging technique that uses near-infrared (NIR) light for intra-operative tumor visualization using the well-known fluorophore indocyanine green (ICG). Because schwannomas often incorporate the nerve into the encapsulated tumor and impinge on surrounding neural structures, SWIG is a promising technique to improve tumor resection while sparing the nerve. OBJECTIVE: To demonstrate the use of SWIG in resection of cranial nerve schwannomas. METHODS: Three patients with cranial nerve schwannomas (i.e., trigeminal, vestibular, and vagus) underwent SWIG-guided resection. During surgery, NIR visualization was used intermittently used to detect fluorescence to guide resection. Signal-to-background ratio was then calculated to quantify fluorescence. RESULTS: Patients were infused with ICG at a dose of 5.0 mg/kg 24 hours before surgery. Each patient achieved total or near-total resection and relief of symptoms with lack of recurrence at six-month follow-up. The average SBR calculated was 3.79, comparable to values for SWIG-guided resection of other brain and spine tumors. CONCLUSION: This case series is the first published report of trigeminal and vagus nerve schwannoma resection using the SWIG technique and suggests that SWIG may be used to detect all schwannomas, alongside many other types of brain tumor. This paper also demonstrates the importance of preoperative ICG infusion timing and discusses the inverse pattern of NIR signal that may be observed when infusion occurs outside of the optimal timing. This provides direction for future studies investigating the administration of SWIG to resect cranial nerve schwannomas and other brain tumors.

The impact of mental health on health-related quality of life in patients with NF2-related Schwannomatosis.

NF2-related schwannomatosis (NF2-SWN) is a rare genetic disorder and is associated with progressive morbidities. This study aimed to investigate the relationship between NF2-SWN disease severity, health-related Quality of Life (QoL), and mental health aspects of patients. Standardised questionnaires assessing mental health problems (symptoms of depression, anxiety, and somatic burden), psychological factors (resilience, loneliness, and personality functioning), and health-related QoL were administered to 97 patients with NF2-SWN. The results of these questionnaires were compared with physician-rated disease severity. Questionnaires were completed by 77 patients. Physician-rated disease severity scores were available for 55 patients. NF2-SWN patients showed a high prevalence of clinically relevant symptoms of depression (30%), anxiety (16%), and somatic burden (32%). Almost all variables showed moderate to high correlations with NF2-SWN-related QoL. NF2-SWN-related QoL was associated with physician-reported disease severity (r = 0.614). In the stepwise hierarchical linear regression analysis, a significant model with four predictors (disease severity type, depression symptoms, personality functioning, and gender) explained 64% of the variance in NF2-SWN-related QoL. Our results showed a strong association between NF2-SWN-related QoL and depression symptoms. Moreover, personality functioning is an important influencing factor, representing a modifiable construct that can be targeted by prevention programs or psychotherapy.

[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".

Convolutional neural network-based magnetic resonance image differentiation of filum terminale ependymomas from schwannomas.

PURPOSE: Preoperative diagnosis of filum terminale ependymomas (FTEs) versus schwannomas is difficult but essential for surgical planning and prognostic assessment. With the advancement of deep-learning approaches based on convolutional neural networks (CNNs), the aim of this study was to determine whether CNN-based interpretation of magnetic resonance (MR) images of these two tumours could be achieved. METHODS: Contrast-enhanced MRI data from 50 patients with primary FTE and 50 schwannomas in the lumbosacral spinal canal were retrospectively collected and used as training and internal validation datasets. The diagnostic accuracy of MRI was determined by consistency with postoperative histopathological examination. T1-weighted (T1-WI), T2-weighted (T2-WI) and contrast-enhanced T1-weighted (CE-T1) MR images of the sagittal plane containing the tumour mass were selected for analysis. For each sequence, patient MRI data were randomly allocated to 5 groups that further underwent fivefold cross-validation to evaluate the diagnostic efficacy of the CNN models. An additional 34 pairs of cases were used as an external test dataset to validate the CNN classifiers. RESULTS: After comparing multiple backbone CNN models, we developed a diagnostic system using Inception-v3. In the external test dataset, the per-examination combined sensitivities were 0.78 (0.71-0.84, 95% CI) based on T1-weighted images, 0.79 (0.72-0.84, 95% CI) for T2-weighted images, 0.88 (0.83-0.92, 95% CI) for CE-T1 images, and 0.88 (0.83-0.92, 95% CI) for all weighted images. The combined specificities were 0.72 based on T1-WI (0.66-0.78, 95% CI), 0.84 (0.78-0.89, 95% CI) based on T2-WI, 0.74 (0.67-0.80, 95% CI) for CE-T1, and 0.81 (0.76-0.86, 95% CI) for all weighted images. After all three MRI modalities were merged, the receiver operating characteristic (ROC) curve was calculated, and the area under the curve (AUC) was 0.93, with an accuracy of 0.87. CONCLUSIONS: CNN based MRI analysis has the potential to accurately differentiate ependymomas from schwannomas in the lumbar segment.

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.

[Minimally invasive removal of dumbbell shaped schwannomas with transforaminal lumbar fusion: a retrospective study with a minimum 3-year follow-up]. / Minimal'no invazivnoe udalenie ganteleobraznykh shvannom s transforaminal'nym poyasnichnym spondilodezom: retrospektivnoe issledovanie s minimal'nym 3-letnim katamnezom.

Currently, there are no standards in surgical treatment of dumbbell-shaped tumors of lumbo-foraminal region. OBJECTIVE: To evaluate the effectiveness and long-term results of minimally invasive resection of dumbbell-shaped lumbar schwannomas Eden type 2 and 3 combined with transforaminal lumbar interbody fusion and transpedicular stabilization. MATERIAL AND METHODS: A retrospective study included 13 patients (8 men and 5 women) with lumbar dumbbell tumors Eden type 2 and 3 who underwent minimally invasive facetectomy through posterolateral anatomical corridor, microsurgical tumor resection and MI TLIF. We analyzed intraoperative parameters, neurological functions (ASIA scale), clinical characteristics (ODI, SF-36), and complications. Resection quality and area of the multifidus muscle were assessed according to MRI data. All patients were followed-up throughout at least 3-year. RESULTS: Surgery time was 147 min, blood loss - 118 ml, hospital-stay - 7 days. Clinical parameters significantly improved in the follow-up period: ODI score decreased from 72 to 12 (p=0.004), SF-36 PCS increased from 26.24 to 48.51 (p=0.006) and MCS score increased from 29.13 to 53.68 (p=0.002). According to MRI data, no tumor recurrences and severe muscle atrophy (>30%) were observed after 3 years in all cases. Superficial wound infection occurred in 1 (7.7%) case. There were normal neurological functions (ASIA type E) in all patients. CONCLUSION: Minimally invasive facetectomy through posterolateral approach with MI TLIF technology can be used for safe and effective resection of dumbbell-shaped schwannomas Eden type 2 and 3.