A Clinical and Histopathological Analysis of 45 Cases of Cutaneous Neurilemmoma (Schwannomas)

Background: Neurilemmoma (Schwannomas) are the most common peripheral nerve tumors and usually do not undergo malignant transformation, except in some atypical cases. Additionally, the imaging appearance of schwannomas resembles that of neurofibromas, making it difficult to distinguish between the two. Therefore, the clinical diagnosis and treatment of schwannomas may face certain challenges. The management and prognosis of neurilemmomas differ from their malignant counterparts, making correct diagnosis important. Objective: This study evaluates the clinical and histopathological characteristics of 45 cases of neurilemmoma. Methods: This retrospective study involves 45 cases diagnosed with cutaneous neurilemmoma at the Seventh Affiliated Hospital of Sun Yat-sen University between April 2020 and September 2024. All cases were retrieved from medical records. Results: The age range of the 45 patients was 23 to 73 years, with a male to female ratio of 1.6:1. Over half the cases occurred in individuals aged 30 to 59, with most lesions found in the extremities, predominantly in the lower limbs. Disease duration varied from 7 days to 20 years. All tumors were solitary, with diameters ranging from 0.8 cm to 8 cm. Most tumors (33/45, 73.33%) were asymptomatic, though some patients experienced symptoms like pain and numbness. Mass was the most common clinical diagnosis (33/45, 73.33%). Five patients had suspected neurilemmomas prior to surgery. Immunohistochemical staining revealed all positive results for S-100 and SOX-10 markers, while EMA staining showed a negative rate of 93.33%. Most Ki-67 values (19/23, 82.6%) were less than or equal to 5%. Conclusion: The diversity of clinical features, pathological manifestations, and immunohistochemical results of schwannoma poses a challenge to accurate diagnosis. A comprehensive understanding of its clinical and pathological characteristics is essential for accurate diagnosis, and when combined with immunohistochemical analysis, it helps avoid misdiagnosis.

Clinicopathological features and treatment of gastrointestinal schwannomas

BACKGROUND Gastrointestinal schwannomas(GIS)are rare neurogenic tumors arising from Schwann cells in the gastrointestinal tract.Studies on GIS are limited to small case reports or focus on specific tumor sites,underscoring the diagnostic and thera-peutic challenges they pose.AIM To comprehensively examine the clinical features,pathological characteristics,treatment outcomes,associated comorbidities,and prognosis of GIS.METHODS The study population included patients diagnosed with GIS at the First Affiliated Hospital,Zhejiang University School of Medicine,between June 2007 and April 2024.Data were retrospectively collected and analyzed from medical records,including demographic characteristics,endoscopic and imaging findings,treatment modalities,pathological evaluations,and follow-up information.RESULTS In total,229 patients with GIS were included,with a mean age of 56.00 years and a male-to-female ratio of 1:1.83.The mean tumor size was 2.75 cm,and most(76.9%)were located in the stomach.Additionally,6.6%of the patients had other malig-nant tumors.Preoperative imaging and endoscopy frequently misdiagnosed GIS as gastrointestinal stromal tumors.However,accurate preoperative diagnosis was achieved using endoscopic ultrasound-guided fine-needle aspiration combined with immunohistochemical analysis,in which S100 and SOX-10 markers were mostly positive.Smaller tumors were typically managed with endoscopic resection,while larger lesions were treated with surgical resection.Follow-up results showed that most patients experienced favorable outcomes.CONCLUSION Preoperative diagnosis of GIS via clinical characteristics,endoscopy,and imaging examinations remains challenging but crucial.Endoscopic therapy provides a minimally invasive and effective option for patients.

Concomitant treatment of ureteral calculi and ipsilateral pelvic sciatic nerve schwannoma with transperitoneal laparoscopic approach: A case report

BACKGROUND Schwannomas are rare peripheral neural myelin sheath tumors that originate from Schwann cells.Of the different types of schwannomas,pelvic sciatic nerve schwannoma is extremely rare.Definite preoperative diagnosis of pelvic schwannomas is difficult,and surgical resection is the gold standard for its definite diagnosis and treatment.CASE SUMMARY We present a case of pelvic schwannoma arising from the sciatic nerve that was detected in a 40-year-old man who underwent computed tomography for intermittent right lower back pain caused exclusively by a right ureteral calculus.Subsequently,successful transperitoneal laparoscopic surgery was performed for the intact removal of the stone and en bloc resection of the schwannoma.The total operative time was 125 min,and the estimated blood loss was inconspicuous.The surgical procedure was uneventful.The patient was discharged on postoperative day 5 with the simultaneous removal of the urinary catheter.However,the patient presented with motor and sensory disorders of the right lower limb,caused by partial damage to the right sciatic nerve.No tumor recurrence was observed at the postoperative appointment.CONCLUSION Histopathological examination of the specimen confirmed the diagnosis of a schwannoma.Thus,laparoscopic surgery is safe and feasible for concomitant extirpation of pelvic schwannomas and other pelvic and abdominal diseases that require surgical treatment.

Comprehensive evaluation of rare case:From diagnosis to treatment of a sigmoid Schwannoma:A case report

BACKGROUND Schwannomas are uncommon tumors originating from Schwann cells,forming the neural sheath.They account for approximately 2%-6%of all mesenchymal tumors and are most commonly identified in peripheral nerve trunks,with rarity in the gastrointestinal tract.Among gastrointestinal locations,the stomach harbors the majority of nerve sheath tumors,while such occurrences in the sigmoid colon are exceptionally infrequent.CASE SUMMARY This study presented a clinical case involving a 60-year-old female patient who,during colonoscopy,was diagnosed with a submucosal lesion that was later identified as a nerve sheath tumor.The patient underwent surgical resection,and the diagnosis was confirmed through immunohistochemistry.This study highlighted an exceptionally uncommon occurrence of a nerve sheath tumor in the sigmoid colon,which was effectively managed within our department.Additionally,a comprehensive review of relevant studies was conducted.CONCLUSION The preoperative diagnosis of nerve sheath tumors poses challenges,as the definitive diagnosis still relies on pathology and immunohistochemistry.Although categorized as benign,these tumors have the potential to demonstrate malignant behavior.Consequently,the optimal treatment approach entails the complete surgical excision of the tumor,ensuring the absence of residual lesions at the margins.

Unusual Giant Pre-Sacral Multicystic Schwannoma: A Case Report and Differential Diagnosis

Background: Schwannomas are generally benign neoplasms arising from the nerve sheath. Presacral schwannomas are very rare entities and difficult to diagnose, representing less than 15% of all retrorectal space tumors. Benign schwannoma sometimes displays degenerative changes, such as cyst formation, calcification, hemorrhage, and hyalinization. Usually these degenerations are partially seen in the tumors. Objective: To point out that presacral schwannoma can display markedly multilocular cystic degeneration. Case Report: We present this unique case of a 24-year-old man diagnosed with an unusually large pure multilocular cystic schwannoma, which is revealed by digestive, urinary, and nonspecific neurological symptoms. The patient was successfully treated with radical surgery via an anterior approach leading to the recovery of symptoms. Discussion and Conclusion: This tumor was unusual in its totally multicystic appearance and its resemblance to a wide spectrum of lesions that can occur in the pre-sacral space, such as hydatid and developmental cysts. Preoperative diagnosis is essential to prevent major neurological deficits during surgical intervention.

MRI Findings and Diagnostic Significance of Soft Tissue Schwannomas in the Extremities

Objective:To analyze the MRI features and rare manifestations of schwannomas of the extremities to improve diagnosis.Methods:Retrospective analysis of 23 cases of schwannomas in the extremities confirmed by surgical pathology,summarizing its signs,signal characteristics and MRI enhancement.Results:Among the 23 cases,20 were single lesions,and 3 were multiple lesions,resulting in a total of 28 lesions.The distribution of these lesions included 7 in the thigh,9 in the calves,4 in the armpits,3 in the hips,and 4 each in the upper arms and forearms.Additionally,there was one lesion located in the groin.On T1-weighted imaging(T1WI),the lesions showed iso-intensity or hypo-intensity.On T2-weighted imaging(T2WI),they appeared slightly hyperintense or hyper-intense.Some lesions exhibited multiple small vesicle-like higher signals,cystic changes,and fiber spacing on T2WI.Furthermore,one lesion showed a liquid-liquid plane.The“target sign”was observed in 18 lesions(64.3%)and“neuropathic signs”were present in six lesions(21.4%).Finally,it was noted that on MRI enhancement,the lesions demonstrated uniform or uneven enhancement.The lesions were uniformly or unevenly enhanced on MRI enhancement.Conclusions:The MRI findings of schwannoma in the extremities exhibit specific characteristics.The cystic changes on T2WI also display distinct features.Recognition of rare MRI findings,such as cystic changes,liquid-liquid plane and septum,should be emphasized to enhance the accuracy of pre-diagnosing schwannomas.

Clinical Analysis of 81 Cases of Benign Retroperitoneal Schwannoma

Objective： To analyze the clinical manifestations of retroperitoneal schwannoma in order to improve the diagnosis and treatment of this rare disease. Methods： Between January 1951 and September 2004, 81 patients with retroperitoneal schwannoma were retrospectively analyzed. Results： All cases received operative therapy. Sixty cases （74.1%） received a total resection; 12 cases （14.9%） subtotal resection, and 9 cases （11.1%） exploration. During the surgical operation, a single tumor was found in 77 cases （95.1%）, and multiple tumors in 4 cases （4.9%）. Most of the retroperitoneal schwannomas located beside the spine. The tumor was a fusiform, round or oval mass that was sharply circumscribed and encapsulated. Pathologic results showed all 81 cases were benign schwannoma. In the 4 cases of multiple tumors, 2 （2.5%） were diagnosed as double-primary tumors associated with ascending colon adenocarcinoma and lung squamous-cell cancer. One case recurred postoperatively. Conclusion： Retroperitoneal schwannoma was rare and preoperative diagnosis was difficult. Most of retroperitoneal schwannoma were benign and the surgical treatment was the first choice.

颈部迷走神经鞘瘤术后并发淋巴瘘1例报告及文献复习

颈部迷走神经鞘瘤术后常出现声音嘶哑、饮水呛咳、吞咽困难、Horner综合征、乳糜瘘等并发症,但淋巴瘘较为罕见。本文报告1例颈部迷走神经鞘瘤术后并发淋巴瘘病例,结合相关文献报道,对迷走神经鞘瘤的临床表现、诊断、治疗及并发淋巴瘘的处理等进行讨论,以提高对该病及其并发症的认识。

Malignant schwannoma of the pancreas involving transversal colon treated with en-bloc resection

Pancreatic schwannoma is a very uncommon tumor of the pancreas,with only 27 cases reported.Most pancreatic schwannomas are benign,with only four malignant tumors reported.We describe a case of giant malignant schwannoma of the pancreatic body and tail,which involved the transverse colon.The tumor was treated successfully with en bloc distal splenopancreatectomy and colon resection.This is believed to be the first reported radical operation for malignant schwannoma of the pancreatic body,with infiltration of the transverse colon,with excellent longterm results.The patient is alive and well 28 mo after the operation.The authors conclude that pancreatic schwannomas should be considered in the differential diagnosis of cystic neoplasms of the pancreas,although the diagnosis can only be confirmed by microscopic examination.In the case of the benign tumors,local excision is adequate,but in the case of malignant schwannoma,oncological standards must be fulfilled.

Clinical characteristics and surgical treatment of schwannomas of the esophagus and stomach: A case series and systematic review

BACKGROUND Gastrointestinal schwannomas are slow-growing benign mesenchymal neoplasms that originate from Schwann cells of the nerve sheath of Auerbach′s plexus or less frequently from Meissner′s plexus.The main differential diagnosis of gastric schwannomas are the gastrointestinal stromal tumors(GISTs),which are classified by their immunohistochemistry.The treatment of choice for gastric schwannomas is surgery where laparoscopy plays an important role.Wedge resection,subtotal or total gastrectomy can be done.In its counterpart,esophageal schwannomas are benign tumors of the esophagus that are very uncommon since they comprise less than 2%of all esophageal tumors.The main differential diagnosis is the leiomyoma which corresponds to the most common benign esophageal tumor,followed by GIST.The treatment consists on tumoral enucleation or esophagectomy.AIM To review the available literature about gastrointestinal schwannomas;especially lesions from de stomach and esophagus,including diagnosis,treatment,and follow up,as well as,reporting our institutional experience.METHODS A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines.The following databases were used for reviewing process:Pub Med,Ovid,MEDLINE,and Scopus.Only English language manuscripts were included.All gastrointestinal schwannomas specifically located in the esophagus and stomach were included.Cases that did not report long-term follow-up were excluded.RESULTS Gastric localization showed a higher prevalence in both,the literature review and our institution:94.95%(n=317)and 83%(n=5)respectively.With a follow-up with disease-free survival greater than 36 mo in most cases:62.01%(n=80)vs66.66%(n=4).In both groups,the median size was>4.1 cm.Surgical treatment is curative in most cases CONCLUSION Schwannoma must be taken into account in the differential diagnosis of gastrointestinal mesenchymal tumors.It has a good prognosis,and most are benign.A disease-free survival of more than 36 mo can be achieved by surgery.

Imaging characteristics and surgical management of orbital neurilemmomas

AIM: To review imaging characteristics and surgical outcomes of orbital neurilemmoma. METHODS: Retrospective review of 21 patients with orbital neurilemmoma managed at the Zhongshan Ophthalmic Center of Sun Yat-sen University from June 2005 to December 2016. All patients underwent surgical excision following preoperative imaging including ultrasonography, computed tomography(CT) and magnetic resonance imaging(MRI).RESULTS: Among these patients, 11 were male and 10 were female, with age ranging from 12 to 75y(average, 40.3 y). Ultrasound of the orbit showed a roundish well-demarcated orbital mass with low or middle internal reflectivity in each case. Dark inner liquid fields were detected in 28.6% of these cases. Doppler ultrasound demonstrated blood flow signals in these masses. CT showed that the tumors were either homogeneous or heterogeneous. MRI of T1 WI revealed isointense or hypointense tumors, while the T2 WI indicated heterogeneous hyperintense lesions. Gd contrast MRI demonstrated heterogenous or homogeneous enhancement initiating from the wide area of the lesion. Six patients underwent lateral orbitotomy and 15 anterior orbitotomy. All tumors were completely removed. After a mean followup of 1.8 y, 3 patients experienced reduced vision while the remaining 10 patients showed improved vision after surgery. One patient experienced a mild limitation of upward motility. No recurrence occurred. CONCLUSION: Orbital neurilemmoma is a relatively rare, benign orbital tumor. Effective diagnosis requires a combination of ultrasonography, CT and/or MRI. These imaging techniques are also vital to differentiate neurilemmomas from other orbital masses like that of cavernous hemangiomas and meningiomas.Successful treatment requires complete resection of the neurilemmomas as performed either by lateral or anterior orbitotomy. Recurrence is rare after complete removal.

Bowel mesentery(meso-appendix) microcystic/reticular schwannoma: Case report and literature review

Microcystic/reticular schwannoma is a recently described variant of schwannoma with a predilection for the gastrointestinal tract. Due to overlapping features with other tumors, unawareness of this tumor type may lead to diagnostic and therapeutic pitfalls. We here report a case of microcystic/reticular schwannoma arising in the meso-appendix of a 43-year-old woman. The tumor was incidentally discovered by computed tomography scan for unrelated reasons. A laparoscopic operation was performed shortly after admission. Histological examination revealed a circumscribed tumor with a striking microcystic and cribriform architecture. Immunohistochemically, the tumor cells were diffusely positive for S100 protein, glial fibrillary acid protein and protein gene product 9.5, which were consistent with a peripheral nerve sheath tumor. The patient remains well with no signs of recurrence at a 10-mo follow-up. To our knowledge, this is the first case of microcystic/reticular schwannoma arising in the meso-appendix. Albeit very rare, microcystic/reticular schwannoma should be included in the differential diagnosis of appendiceal tumors.

Gastroduodenal intussusception due to gastric schwannoma treated by billroth Ⅱ distal gastrectomy:One case report

Schwannomas are rarely observed in the gastrointestinal tract.The most common symptoms of a gastric schwannoma are abdominal pain or dyspepsia,gastrointestinal bleeding,and an abdominal mass.Many gastric schwannomas are asymptomatic and are discovered incidentally or at postmortem.The diagnosis of a schwannoma is based on immunohistochemical positivity for S-100 protein.Wepresent a case report of a rare complication of gastric schwannoma causing gastroduodenal intussusception that was successfully managed by a BillrothⅡdistal gastrectomy.In this rare case,the patient had intermittent,colicky abdominal pain,nausea,and vomiting for over 4wk accompanied by a weight loss.A diagnosis of gastric intussusception was made by computed tomography.A BillrothⅡdistal gastrectomy was then performed,and complete en bloc removal(R0 resection)was achieved.Pathology confirmed a gastric schwannoma through positive immunohistochemical staining for S-100 protein.

Primary hepatic benign schwannoma

Schwannoma is predominantly a benign neoplasm of the Schwann cells in the neural sheath of the peripheral nerves.Occurrence of schwannoma in parenchymatous organs,such as liver,is extremely rare.A 64-year-old man without neurofibromatosis was observed to have a space-occupying lesion of 23mm diameter in the liver during follow-up examination for a previously resected gastrointestinal stromal tumor(GIST)in the small intestine.He underwent lateral segmentectomy of the liver under a provisional diagnosis of hepatic metastatic recurrence of the GIST.Histological examination confirmed the diagnosis of a benign schwannoma,confirmed by characteristic pathological findings and positive immunoreactions with the neurogenic marker S-100 protein,but negative for c-kit,or CD34.The tumor was the smallest among the reported cases.When the primary hepatic schwannoma is small in size,preopera- tive clinical diagnosis is difficult.Therefore,this disease should be listed as differential diagnosis for liver tumor with clinically benign characteristics.

“Wait and scan” management of patients with vestibular schwannoma and the relevance of non-contrast MRI in the follow-up

Vestibular schwannoma(VS) is a slow-growing benign neoplasm. There has been an evolution in the management of VS from active treatments(microsurgery and stereotactic radiotherapy) to conservative management(wait and scan). Regular MRI scanning is necessary to monitor tumor progression. Conservative management causes significantly less complications and offers a higher quality of life compared with active treatments. The mean growth rate of VS varies from 0.4 to 2.9 mm/year, and spontaneous shrinkage is observed in 3.8 percent of tumors during observation. If significant growth occurs, active treatment is considered. Significant growth is defined as an increase of at least 3 mm in the largest extrameatal diameter in any plane between the first and last available scans. The vestibulocochlear nerve is surrounded by cerebrospinal fluid, which provides natural contrast for MRI; thus, gadolinium may not be needed to detect VS. Specific sequences have high sensitivity, specificity, and accuracy for detection of progression. Hypointense signal in the ipsilateral inner ear fluid might be a useful sign to distinguish VS from meningioma. In this paper, we summarize the current status of research on conservative management and non-contrast MRI for the detection of VS.

Central pancreatectomy for pancreatic schwannoma: A case report and literature review

Schwannomas are mesenchymal tumors originating from Schwann cells in peripheral nerve sheaths. Although the tumor can be located in any part of the human body, the most common locations are the head, neck, trunk and extremities. Pancreaticschwannomas are rare. To our knowledge, only 64 cases of pancreatic schwannoma have been reported in the English literature over the past 40 years. In this paper, we present a pancreatic schwannoma in a 59-year-old female. Ultrasound, computed tomography and magnetic resonance imaging revealed the tumor located in the pancreatic body; however, accurate diagnosis was hard to obtain preoperatively and a pancreatic cystadenoma was preliminarily considered. During laparotomy, the mass was found in the body of the pancreas. An enlarged gallbladder with multiple stones was also observed. We performed central pancreatectomy, end-to-side pancreaticojejunostomy and cholecystectomy. Notably, central pancreatectomy has been reported in only one case prior to this report. The gross specimen showed a mass with a thin capsule, 1.6 cm × 1.1 cm × 1.1 cm in size. Microscopic examination showed that the tumor was mainly composed of spindle-shaped cells with palisading arrangement and no atypia, which is consistent with a benign tumor. Both hypercellular and hypocellular areas were visible. Immunohistochemical staining revealed strongly positive results for protein S-100. Finally, the tumor was diagnosed as a schwannoma of the pancreatic body. Postoperatively, the patient recovered well and left the hospital 6 d later. During the 53-mo follow-up period, the patient remained well and free of complications.

Solitary schwannoma of the gallbladder: A case report and literature review

Schwannomas occurring in the gallbladder are extremely rare. Preoperative diagnosis of gallbladder schwannomas appears to be very difficult because they are normally asymptomatic and are often found incidentally. Until now, only five cases have been reported in the literature. To our knowledge, the contrast-enhanced ultrasound (CEUS) features of gallbladder schwannomas have not been reported before in other studies. We treated a 55-year-old male patient with gallbladder schwannoma in China. He had no symptoms, and the lesion was incidentally found by conventional ultrasound (US) when performing a health examination. The patient had normal liver function; moreover, serum carcinoembryonic antigen and alpha-fetoprotein were within the normal ranges. The lesion showed no blood flow signals on color Doppler US, and the wall beneath the lesion was intact on CEUS. The lesion was believed to be a benign entity; in addition, gallbladder adenomyomatosis was suspected. A laparoscopic cholecystectomy was performed to remove the mass. Pathological examination revealed that the tumor was mainly composed of spindle-shaped cells; neither atypical cells nor signs of malignancy were found. Immunohistochemical staining showed a strong positive S-100 protein reaction. Vimentin and CD56 staining were also positive, whereas CD34 and CD117 were negative. Finally, the lesion was diagnosed as schwannoma. Herein, we report the case; the associated literature is also reviewed. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.

Combined thoracoscopic and endoscopic surgery for a large esophageal schwannoma

A 47-year-old woman presented to our hospital with complaints of dysphagia. Esophagogastroduodenoscopy identified a submucosal tumor in the left wall of the esophagus that was diagnosed as a benign schwannoma on biopsy. Computed tomography revealed a tumor of length 60 mm in the thoracic esophagus, with its cranial edge at the level of the aortic arch. On endoscopy, a submucosal tunnel was created 40 mm proximal to the cranial edge of the tumor, and its oral end was dissected from the mucosal and muscular layers. This was followed by the resection of the entire tumor by left-sided thoracoscopy. The esophageal defect was closed in layer by continuous suture from the thoracic side. Endoscopic closure was achieved by using clips. No postoperative complications were observed. Oral diet was resumed from postoperative day 7 and the patient was discharged on postoperative day 9. This combined approach has not been described for similar tumors. Our experience demonstrated that large esophageal tumors can be safely excised with minimally invasive surgery by using a combination of thoracoscopy and endoscopy.

Hemi-semi Laminectomy Approach for the Microsurgical Treatment of Spinal Schwannomas

Objective To evaluate the safety and efficiency of hemi-semi laminectomy approach for the micro- surgical treatment of spinal schwannomas. Methods A total of 22 patients underwent hemi-semi laminectomy for the microsurgical removal of spinal schwannomas during a period of 2009 and 2011 in Affiliated Hospital of Nantong University. We ret- rospectively analyzed the clinical outcomes of these patients. Results Of them, 5 cases were diagnosed with cervical schwannomas, 9 with thoracic schwarmomas, and 8 with lumbar schwannomas. All the tumors including two dumbbell schwannomas were totally removed without major complications. Postoperatively, all patients were followed up from 6 to 36 months. The symp- toms and signs were obviously improved, and no tumor recurrence or spinal deformity occurred. Conclusion Hemi-semi laminectomy is a safe and effective method for resection of spinal schwan- nomas

Schwannoma originating from the recurrent laryngeal nerve in a thyroid cancer patient: A case report and review of the literature

BACKGROUND Schwannoma rarely originates from the recurrent laryngeal nerve, and there are few reports on schwannoma originating from the recurrent nerve in the mediastinum. Herein, we present an extremely rare case of schwannoma originating from the recurrent laryngeal nerve in the neck.CASE SUMMARY This is a case report of one patient diagnosed with thyroid cancer with schwannoma originating from the recurrent laryngeal nerve in the neck, which was incidentally found during a thyroidectomy, and a review of the literature.CONCLUSION Preoperative diagnostic examinations are of less use for detecting schwannoma originating from a recurrent laryngeal nerve in the neck in such small size, which may only incidentally be found during a thyroidectomy. Surgical excision with opening the capsule and shelling out the tumor is the treatment of choice. If the nerve is unable to be preserved, end-to-end recurrent laryngeal nerve anastomosis may be a simple and minimally invasive reconstruction procedure to improve phonation.