Sigmoid colon schwannoma is a rare benign gastrointestinal tumor that is challenging to be diagnosed preoperatively.This paper reported a case of sigmoid colon schwannoma that was preoperatively misdiagnosed as a gastrointestinal stromal tumor on ultrasonography.Intraoperative frozen section analysis identified it as a spindle cell tumor,with definitive diagnosis confirmed as gastrointestinal schwannoma via immunohistochemistry.This paper summarizes the similarities and differentiating features of intestinal stromal tumors and schwannomas on ultrasonographic imaging.By analyzing and discussing previous literature,we aim to enhance the diagnostic and differential diagnostic capabilities of ultrasonographers in preoperative evaluation of intestinal schwannomas,thereby providing reliable evidence for clinicians in the diagnosis and management of this condition.
Humans ; Neurilemmoma/diagnostic imaging* ; Ultrasonography ; Sigmoid Neoplasms/diagnostic imaging* ; Male ; Colon, Sigmoid/diagnostic imaging* ; Middle Aged ; Female ; Diagnosis, Differential

OBJECTIVES

To highlight the clinical presentation, diagnostic dilemma and proposed management of a case of a transmodiolar intralabyrinthine schwannoma.

Design:Case Report

Setting:Tertiary National University Hospital

Patient:One

A 51-year-old woman consulted for a 12-year history of unilateral sensorineural hearing loss and progressively worsening vertigo. Workups revealed a hyperintense lesion approximating the entire right cochlea on Gadolinium-enhanced magnetic resonance imaging and profound hearing loss on the right on pure-tone audiometry, with no recordable response even at maximum intensity levels across all frequencies. Infectious and metastatic workups returned negative results, clinching the radiographic diagnosis of an intralabyrinthine schwannoma.

Intralabyrinthine schwannomas (ILS) are rare, benign neoplasms of the 8th cranial nerve, manifesting as progressive unilateral sensorineural hearing loss and worsening vertigo. These neoplasms are mainly detected by MRI; underdiagnosis and lack of standard treatment and diagnostic protocols result in their inaccurate diagnosis and delays in management.

Objective:To analyze the clinical characteristics and risk factors of postoperative first bite syndrome（FBS） after parapharyngeal space surgery, and to provide evidence-based recommendations for the diagnosis and management of this complication. Methods:A retrospective analysis was conducted on 142 patients undergoing parapharyngeal space surgery from March 2016 to November 2024, including 12 cases of postoperative FBS. Univariate analysis compared differences in tumor location, pathological type, and surgical approach between FBS and non-FBS groups. Multivariate logistic regression identified independent risk factors. A systematic literature review evaluated the preventive value of transoral endoscopic surgery for FBS, followed by proposed clinical optimization strategies. Results:The incidence of FBS was 8.45%（12/142）. Univariate analysis revealed significant associations with: Superior parapharyngeal space tumors（OR=3.21, 95%CI 1.12-9.21, P=0.029）; Schwannoma pathology（OR=4.05, 95%CI 1.35-12.18, P=0.013）; Traditional lateral cervical approach（OR=5.67, 95%CI 1.89-17.02, P=0.002）. Multivariate analysis confirmed lateral cervical approach（aOR=4.98, 95%CI 1.62-15.31, P=0.005） and schwannoma（aOR=3.75, 95%CI 1.22-11.51, P=0.021） as independent risk factors. Literature review suggested lower FBS rates with transoral endoscopic approaches. The overall effect of the drug on FBS is poor. Conclusion:FBS is a frequent complication of parapharyngeal space surgery, significantly associated with tumor location, pathology, and surgical approach. Transoral endoscopic surgery can effectively reduce the risk of FBS through precise anatomical dissection that minimizes sympathetic nerve injury. Minimally invasive approaches are recommended for eligible cases.
Humans ; Retrospective Studies ; Postoperative Complications/etiology* ; Risk Factors ; Endoscopy ; Parapharyngeal Space/surgery* ; Male ; Female ; Adult ; Middle Aged ; Neurilemmoma/surgery*

Objective:To summarize the initial experience and evaluate the technical feasibility of the endoscopic transcanal transpromontorial approach（TTA） for vestibular schwannoma resection by analyzing long-term follow-up outcomes. Methods:A retrospective analysis was conducted on the perioperative and long-term follow-up data（mean follow-up time: 5 years） of patients who underwent endoscopic TTA for vestibular schwannoma resection in the Department of Otorhinolaryngology Head and Neck Surgery at Xiangya Hospital, Central South University, between January 2020 and December 2020. Long-term outcomes were systematically evaluated. Results:This study included two patients（one 41-year-old male and one 51-year-old female）. According to the AAO-HNS hearing classification system, preoperative hearing was Class C in one patient and Class D in the other. Preoperative imaging confirmed Koos stageⅠ tumors in both cases. Postoperative transient facial nerve paralysis（House-Brackmann Grade Ⅲ） recovered to Grade Ⅰ within 4 months. No complications such as cerebrospinal fluid leakage, intracranial infection, or intracranial hemorrhage occurred. No tumor recurrence was observed during the 5-year follow-up period. Conclusion:The endoscopic transcanal transpromontorial approach is minimally invasive, facilitates rapid recovery, and demonstrates satisfactory technical feasibility and safety when strict patient selection criteria（Koos stageⅠtumors with non-serviceable hearing） are applied.
Humans ; Neuroma, Acoustic/surgery* ; Male ; Adult ; Middle Aged ; Retrospective Studies ; Female ; Endoscopy/methods* ; Follow-Up Studies ; Treatment Outcome

Objective:This study aimed to analyze the results of auditory and vestibular function tests in patients with unilateral vestibular schwannoma and explore their association with tumor size. Methods:Clinical data from 81 patients diagnosed with unilateral vestibular schwannoma who underwent pure-tone audiometry（PTA）, cervical and ocular vestibular evoked myogenic potentials（c/oVEMP）, as well as video head impulse test（vHIT）, and subsequently underwent surgical treatment, were retrospectively analyzed. Patients were categorized into groups based on tumor size: small （≤ 15 mm）, medium（16-30 mm）, and large （>30 mm）, determined by the maximum tumor diameter on contrast-enhanced MRI scans. Results:PTA results indicated hearing loss in 73 cases（90.1%）; vestibular function tests revealed abnormal rates for the anterior semicircular canal, horizontal semicircular canal, posterior semicircular canal, utricle, and saccule at 29.6%, 77.8%, 54.3%, 90.1%, and 92.6%, respectively. Statistically, no significant differences were found in preoperative hearing test results among patients in different groups（F=0.393, P=0.676）. However, significant differences were observed in horizontal semicircular canal gain（r=-0.248, P=0.025）, abnormal rates of horizontal semicircular canal catch-up saccades（r=0.507, P<0.001）, as well as cVEMP（χ²=15.111, P=0.004） and oVEMP thresholds（χ²=18.948, P<0.001） across varying tumor size groups. Conclusion:The extent of hearing loss in patients with vestibular schwannoma is not correlated with tumor size, whereas the degree of vestibular dysfunction demonstrates a correlation with tumor size.
Humans ; Neuroma, Acoustic/physiopathology* ; Retrospective Studies ; Audiometry, Pure-Tone ; Vestibular Function Tests ; Vestibular Evoked Myogenic Potentials ; Female ; Male ; Head Impulse Test ; Middle Aged ; Adult ; Semicircular Canals/physiopathology* ; Aged ; Hearing Loss/physiopathology*

Objective: To examine the feasibility and surgical approach of removing type D trigeminal schwannoma through nasal cavity and nasal sinus under endoscope. Methods: Eleven patients with trigeminal schwannoma who were treated in the Department of Otorhinolaryngology, Qilu Hospital of Shandong University from December 2014 to August 2021 were analyzed retrospectively in this study. There were 7 males and 4 females, aged (47.5±13.5) years (range: 12 to 64 years). The neoplasm involved the pterygopalatine fossa, infratemporal fossa, ethmoidal sinus, sphenoid sinus, cavernous sinus, and middle cranial fossa. The size of tumors were between 1.6 cm×2.0 cm×2.0 cm and 5.7 cm×6.0 cm×6.0 cm. Under general anesthesia, the tumors were resected through the transpterygoid approach in 4 cases, through the prelacrimal recess approach in 4 cases, through the extended prelacrimal recess approach in 2 cases, and through the endoscopic medial maxillectomy approach in 1 case. The nasal endoscopy and imaging examination were conducted to detect whether neoplasm recurred or not, and the main clinical symptoms during follow-up. Results: All the surgical procedures were performed under endonasal endoscope, including Gross total resection in 10 patients. The tumor of a 12-year-old patient was not resected completely due to huge tumor size and limited operation space. One patient was accompanied by two other schwannomas located in the occipital region and the ipsilateral parotid gland region originating from the zygomatic branch of the facial nerve, both of which were removed concurrently. After tumor resection, the dura mater of middle cranial fossa was directly exposed in the nasal sinus in 2 cases, including 1 case accompanied by cerebrospinal fluid leakage which was reconstructed by a free mucosal flap obtained from the middle turbinate, the other case was packed by the autologous fat to protect the dura mater. The operation time was (M(IQR)) 180 (160) minutes (range: 120 to 485 minutes). No complications and deaths were observed. No recurrence was observed in the 10 patients with total tumor resection during a 58 (68) months' (range: 10 to 90 months) follow-up. No obvious change was observed in the facial appearance of all patients during the follow-up. Conclusion: Type D trigeminal schwannoma involving pterygopalatine fossa and infratemporal fossa can be removed safely through purely endoscopic endonasal approach by selecting the appropriate approach according to the size and involvement of the tumor.
Male ; Female ; Humans ; Child ; Retrospective Studies ; Endoscopy/methods* ; Nasal Cavity/surgery* ; Neurilemmoma/surgery* ; Cranial Nerve Neoplasms/surgery*

Objective: To investigate the application of cochlear nerve action potential (CNAP) monitoring in the resection of vestibular schwannoma, especially evaluating its significance for hearing preservation. Methods: From April 2018 to December 2021, 54 patients with vestibular schwannoma who underwent resection via retrosigmoid approach were collected in Chinese PLA General Hospital. Before surgery, all patients had effective hearing (AAO-HNS grade C or above). Brainstem auditory evoked potential (BAEP) combined with CNAP monitoring was performed during surgery. The CNAP monitoring was combined with continuous monitoring and cochlear nerve mapping. And patients were divided into hearing preservation group and non-preserved group according to postoperative AAO-HNS grade. SPSS 23.0 software was used to analyze the differences of CNAP and BEAP parameters between the two groups. Results: A total of 54 patients completed intraoperative monitoring and data collection, including 25 males (46.3%) and 29 females (53.7%), aged 27-71 years with an average age of 46.2 years. The maximum tumor diameter were (18.1±5.9) mm (range 10-34 mm). All tumors were totally removed with preserved facial nerve function (House-Brackmann grade I-II). The hearing preservation rate of 54 patients was 51.9% (28/54). During surgery, the V wave extraction rate of BAEP waveform was 85.2% (46/54) before tumor resection, 71.4% (20/28) in the hearing preservation group after tumor resection, and disappeared in the hearing preservation group (0/26). CNAP waveform was elicited in 54 patients during operation. Differences were found in the distribution of CNAP waveforms after tumor resection. The waveforms of the hearing-preserving group were triphasic and biphasic, while those in the non-preserving group were low-level and positive. For hearing preservation group, the amplitude of N1 wave after tumor resection was significantly higher than that before tumor resection[14.45(7.54, 33.85)μV vs 9.13(4.88, 23.35)μV, P=0.022]; However, for the non-preserved group, the amplitude of N1 wave after tumor resection was significantly lower than that before tumor resection [3.07(1.96, 4.60)μV vs 6.55(4.54, 9.71)μV, P=0.007]; After tumor resection, the amplitude was significantly higher than that of the unreserved group [14.45(7.54, 33.85)μV vs 3.07(1.96, 4.60)μV, P<0.001]. Conclusions: BAEP combined with CNAP monitoring is conducive to intraoperative hearing protection, and the application of cochlear nerve mapping can prompt the surgeon to avoid nerve injury. The waveform and N1 amplitude of CNAP after tumor resection have a certain value in predicting postoperative hearing preservation status.
Female ; Male ; Humans ; Middle Aged ; Neuroma, Acoustic/surgery* ; Action Potentials ; Evoked Potentials, Auditory, Brain Stem ; Cochlea ; Cochlear Nerve

OBJECTIVE: To report on a rare case of Neurofibromatosis type 2 (NF2) manifesting as oculomotor nerve palsy and explore its genetic basis. METHODS: A patient with NF2 who had presented at Beijing Ditan Hospital Affiliated to Capital Medical University on July 10, 2021 was selected as the study subject. Cranial and spinal cord magnetic resonance imaging (MRI) was carried out on the patient and his parents. Peripheral blood samples were collected and subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: MRI revealed bilateral vestibular Schwannomas, bilateral cavernous sinus meningiomas, popliteal neurogenic tumors, and multiple subcutaneous nodules in the patient. DNA sequencing revealed that he has harbored a de novo nonsense variant of the NF2 gene, namely c.757A>T, which has replaced a codon (AAG) encoding lysine (K) at position 253 with a stop codon (TAG). This has resulted in removal of the Merlin protein encoded by the NF2 gene from position 253 onwards. The variant was not found in public databases. Bioinformatic analysis suggested that the corresponding amino acid is highly conserved. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was rated as pathogenic (PVS1+PS2+PM2_Supporting+PP3+PP4). CONCLUSION The heterozygous nonsense variant c.757A>T (p.K253*) of the NF2 gene probably underlay the disease in this patient with an early onset, atypical but severe phenotype.
Male ; Humans ; Neurofibromatosis 2/genetics* ; Genes, Neurofibromatosis 2 ; Oculomotor Nerve Diseases/genetics* ; Computational Biology ; Genomics ; Mutation

Objective: To present a rare case of nasal tip schwannoma and describe its resection and reconstruction using combined cartilage grafts. Methods: Design: Case Report Setting: Tertiary Government Training Hospital Patient: One Results: A 13-year-old boy presented with a progressively enlarging nasal tip and severe left nasal obstruction causing breathing difficulties and psychosocial distress. There was a bulging septal mass obstructing 90% of the left nasal cavity. Septal incision biopsy revealed schwannoma and definitive surgery via open rhinoplasty approach was done. The non-encapsulated schwannoma extended from the subcutaneous nasal tip to the left septal mucosa. There was no evidence of skin or cartilage invasion, but prolonged pressure from the expansile schwannoma caused severe lower lateral cartilage and anterior septal atrophy leading to a collapsed and expanded nasal tip after resection. To correct this, a total reconstruction of the anterior tip complex was done using combined ear cartilage seagull wing graft, shield graft and septal extension graft. Conclusion Nasal tip and septal schwannoma is rare and can cause significant nasal obstruction and deformity. Complete excision is vital to avoid recurrence. Total reconstruction of the lower lateral cartilages using autologous septal and ear cartilage grafts may be a safe and effective technique that yields acceptable aesthetic results.
nasal septum ; schwannoma ; ear cartilage ; rhinoplasty ; nasal cartilages ; esthetics ; neurilemmoma ; adolescent

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of breast myofibroblastoma. Methods: The clinicopathological data and prognostic information of 15 patients with breast myofibroblastoma diagnosed at the Department of Pathology of the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China from 2014 to 2022 were collected. Their clinical characteristics, histological subtypes, immunophenotypes and molecular characteristics were analyzed. Results: There were 12 female and 3 male patients, ranging in age from 18 to 78 years, with a median and average age of 52 years. There were 6 cases in the left breast and 9 cases in the right breast, including 12 cases in outer upper quadrant, 2 cases in inner upper quadrant and 1 case in outer lower quadrant. Most of the cases showed a well-defined nodule grossly, including pushing growth under the microscope in 13 cases, being completely separated from the surrounding breast tissue in 1 case, and infiltrating growth in 1 case. Among them, 12 cases were classic subtype and composed of occasional spindle cells with varying intervals of collagen fiber bundles; eight cases had a small amount of fat; one case had focal cartilage differentiation; one case was epithelioid subtype, in which epithelioid tumor cells were scattered in single filing or small clusters; one case was schwannoma-like subtype, and the tumor cells were arranged in a significant palisade shape, resembling schwannoma, and one case was invasive leiomyoma-like subtype, in which the tumor cells had eosinophilic cytoplasm and were arranged in bundles, and infiltrating into the surrounding mammary lobules like leiomyoma. Immunohistochemical studies showed that the tumor cells expressed desmin (14/15) and CD34 (14/15), as well as ER (15/15) and PR (15/15). Three cases with histologic subtypes of epithelioid subtype, schwannoma-like subtype and infiltrating leiomyoma-like subtype showed RB1 negative immunohistochemistry. Then FISH was performed to detect RB1/13q14 gene deletion, and identified RB1 gene deletion in all three cases. Fifteen cases were followed up for 2-100 months, and no recurrence was noted. Conclusions: Myofibroblastoma is a rare benign mesenchymal tumor of the breast. In addition to the classic type, there are many histological variants, among which the epithelioid subtype is easily confused with invasive lobular carcinoma. The schwannoma-like subtype is similar to schwannoma, while the invasive subtype is easily misdiagnosed as fibromatosis-like or spindle cell metaplastic carcinoma. Therefore, it is important to recognize the various histological subtypes and clinicopathological features of the tumor for making correct pathological diagnosis and rational clinical treatment.
Female ; Humans ; Male ; Antigens, CD34 ; Biomarkers, Tumor/analysis* ; Leiomyoma/pathology* ; Neoplasms, Muscle Tissue/pathology* ; Neurilemmoma ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged