Magnetic resonance imaging findings for differential diagnosis of perianal plexiform schwannoma: Case report and review of the literature

Plexiform schwannoma is an extremely rare variant of schwannoma, accounting for approximately 5% of cases. Due to the rarity and lack of typical symptoms, signs and radiological images, a definite diagnosis of plexiform schwannoma may not be made by clinicians prior to biopsy. In the present study, we report the first case(to our knowledge) of perianal plexiform schwannoma arising from the overlapped skin of the ischioanal fossa, and we propose an intratumorally nonenhanced circumferential capsule dividing the tumour into multiple homogeneously enhanced nodules as a magnetic resonance imaging feature to aid in the differential diagnosis of plexiform schwannoma from ancient schwannoma, cavernous haemangioma, liposarcoma and plexiform neurofibroma.

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.

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.

Values of macular ganglion cell-inner plexiform layer and 10-2 visual field measurements in detecting and evaluating glaucoma

AIM:To assess the performance of macular ganglion cell-inner plexiform layer thickness(mGCIPLT)and 10-2 visual field(VF)parameters in detecting early glaucoma and evaluating the severity of advanced glaucoma.METHODS:Totally 127 eyes from 89 participants(36 eyes of 19 healthy participants,45 eyes of 31 early glaucoma patients and 46 eyes of 39 advanced glaucoma patients)were included.The relationships between the optical coherence tomography(OCT)-derived parameters and VF sensitivity were determined.Patients with early glaucoma were divided into eyes with or without central 10°of the VF damages(CVFDs),and the diagnostic performances of OCT-derived parameters were assessed.RESULTS:In early glaucoma,the mGCIPLT was significantly correlated with 10-2 VF pattern standard deviation(PSD;with average mGCIPLT:β=-0.046,95%CI,-0.067 to-0.024,P<0.001).In advanced glaucoma,the mGCIPLT was related to the 24-2 VF mean deviation(MD;with average mGCIPLT:β=0.397,95%CI,0.199 to 0.595,P<0.001),10-2 VF MD(with average mGCIPLT:β=0.762,95%CI,0.485 to 1.038,P<0.001)and 24-2 VF PSD(with average mGCIPLT:β=0.244,95%CI,0.124 to 0.364,P<0.001).Except for the minimum and superotemporal mGCIPLT,the decrease of mGCIPLT in early glaucomatous eyes with CVFDs was more severe than that of early glaucomatous eyes without CVFDs.The area under the curve(AUC)of the average mGCIPLT(AUC=0.949,95%CI,0.868 to 0.982)was greater than that of the average circumpapillary retinal nerve fiber layer thickness(cpRNFLT;AUC=0.827,95%CI,0.674 to 0.918)and rim area(AUC=0.799,95%CI,0.610 to 0.907)in early glaucomatous eyes with CVFDs versus normal eyes.CONCLUSION:The 10-2 VF and mGCIPLT parameters are complementary to 24-2 VF,cpRNFLT and ONH parameters,especially in detecting early glaucoma with CVFDs and evaluating the severity of advanced glaucoma in group level.

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.

Intracochlear schwannoma: Imaging diagnosis

Intralabyrinthine schwannomas(ILS)are rare benign tumors,often responsible for hearing loss.MRI is important in establishing the diagnosis.We present the example of a 48-year-old lady who reported a 3-years history of right-sided sensorineural deafness.MRI demonstrated a loss of the normal hypersignal of the second turn of the right cochlea compatible with intracochlear schwannoma.

Giant Spinal Schwannomas. Presentation of Two Cases with Interdisciplinary Surgical Resection

Purpose: To report two quite rare cases of giant schwannomas of the cervical and thoracic spine. Surgical resection is usually the treatment of choice for these neoplasms. Methods: The first patient is a 48-year-old male that came to our department, complaining about weakness and paresthesia of both lower extremities and upper left extremity, and a considerably big dorsal palpable lump. MRI and CT scan were used to diagnose giant cervical schwannoma. Because of the intensity of symptoms, he was subjected to surgery. Multidisciplinary resection involving neurosurgical and oncosurgicalteamn was performed for intravertebral and extravertebral approaches. The second patient is a 55-year-old female that came to the hospital complaining about incapacitating pain and dysesthesia involving T6, T7, and T8 dermatomes, with no other deficits. MRI and CT scan were used to diagnose giant thoracic schwannoma. Because of the intensity of the pain, surgery was decided as the treatment of choice. Video assisted thoracoscopic surgery was performed and total resection was achieved, with improvement of the symptoms. Results: Both patients showed complete remission of the symptoms, with no major deficits after surgery. Conclusion: Although infrequent, giant spinal schwannomas may be the cause of visible lumps in the back with radicular symptoms. When asymptomatic, conservative treatment could be viable, but when they present symptoms, surgery offers good results.

Plexiform Schwannoma: A Report of Two Unusual Cases, and a Review of the Literature

Plexiform schwannoma is a benign tumour arising from the sheath of myelinated nerve fibres that may occur in any part of the body. It is very rare in the head and neck region and poses diagnostic challenges. Here we present two unusual cases. The first is about a fifteen-year-old boy with a large plexiform schwannoma in the right retro maxillary region, extending up to but not invading the orbit. Initial cytology reported it as a pleomorphic adenoma, but histological findings after excision confirmed it to be a benign plexiform schwannoma. A zygomatic osteotomy was required to excise the tumour in its entirety. The second reported case is about solitary lesion on the tongue of a 46-year-old Chinese man, clinically mimicking a mucocoele. This case report highlights the diagnostic challenges posed by plexiform schwannoma, and the role of imaging and cytopathology, as well as the importance of definitive histopathological analysis. It also describes the surgical management of these lesions, and provides a review of the literature, in particular of cases occurring in the head and neck region.

Total removal of a large esophageal schwannoma by submucosal tunneling endoscopic resection:A case report and review of literature

BACKGROUND Primary schwannoma is a rare submucosal tumor of the esophagus,which is most often benign,and surgery is the only effective treatment.So far,only a few cases have been reported.Herein,we reported a single case diagnosed with primary esophageal schwannoma that was totally removed by submucosal tunneling endoscopic resection(STER).CASE SUMMARY A 62-year-old man presented to the hospital with a history of resection of a malignant gastric tumor and mild dysphagia.Endoscopic examination revealed a large submucosal elevated lesion in the esophagus 25-30 cm from the incisors.Endoscopic ultrasonography detected a 45 mm×35 mm×31 mm hypoechoic lesion;chest computed tomography showed a mass of approximately 55 mm×35 mm×29 mm.A preliminary examination showed features suggestive of a stromal tumor.Pathological findings indicated esophageal schwannoma.Next,STER alone was performed to completely resect the mass,and the patient recovered well post-surgery.Afterward,the patient was discharged and showed no tumor recurrence at 33 mo of follow-up.CONCLUSION Endoscopic resection is still an effective treatment for large esophageal schwannomas(>30 mm)under meticulous morphological evaluation.

Removal of unexpected schwannoma with superficial parotidectomy using modified-Blair incision and superficial musculoaponeurotic system folding: A case report

BACKGROUND When a firm facial mass in the cheek region is associated with a high index of clinical suspicion of its being of parotid gland origin,preventive parotidectomy is invariably performed.We report a rare case of a schwannoma that was suspected to be of parotid gland origin in a patient,who underwent successful surgical management using a modified-Blair incision and superficial musculoaponeurotic system(SMAS)layer folding method.CASE SUMMARY A 27-year-old woman presented to the hospital for evaluation of a firm,fixed,non-tender mass(2.5 cm×3.5 cm),located anterior to the right ear,of 1 year’s duration.Contrast-enhanced facial computed tomography revealed a wellencapsulated,low-density mass adherent to the superficial lobe of the right parotid gland,with a high index of clinical suspicion of an accessory parotid gland mass.The patient was scheduled to undergo resection of the mass and superficial parotidectomy.She underwent surgery using a modified-Blair incision,and the SMAS layer was folded posteriorly to reconstruct the defect.Histopathological examination confirmed the diagnosis of a schwannoma.,and we observed no postoperative complications such as hematoma,infection,or abnormal facial expressions.The incision scar was unnoticeable 2 mo postoperatively,and the facial contour was maintained without any differences between the affected and unaffected sides.CONCLUSION We used a modified-Blair incision and SMAS layer folding method to achieve aesthetically good results following resection of a rare schwannoma with superficial parotidectomy in the cheek region.

Misdiagnosis of Facial Nerve Palsy: A Case Report of Sporadic Vestibular Schwannomas (Non-NFM2) Causing Facial Nerve Palsy Be Misled by Bell’s Palsy in a Child

We report a case of a rare sporadic Vestibular Schwannoma of a 9-month-old girl who had a right-sided lower motor type facial nerve palsy. The patient was initially diagnosed with Bell’s palsy and received steroid treatment accordingly, two months later the patient’s condition deteriorated, and further evaluation of CT and MRI brain was conducted that showed a mass lesion in the posterior fossa causing compression on the facial nerve. Misdiagnosis of facial nerve paralysis is common among children due to multiple related etiologies and varying rates of incidence in comparison to adults. The authors hope to address this issue in this report. Background: Facial nerve paralysis has been a matter of concern for many researchers to understand its nature, causes and presentation according to different age groups. In adults, Bell’s palsy (BP), the idiopathic form of facial nerve paralysis, is more common compared to children where most cases are due to secondary etiologies. Therefore, pediatricians are in an important position to identify these patients early in order to launch the most effective diagnostic and treatment approaches.

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.

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.

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.