Primary Peritracheal Schwannoma: Report of a Case

Posterior mediastinal tumors of neurogenic origin commonly arise from the sympathetic or intercostal nerves. However, anterior mediastinal tumors rarely originate from the vagus nerve, and primary neurogenic tumors of the trachea are extremely uncommon. A 19-year-old man was admitted to an emergency department in sudden acute respiratory distress. A tracheostomy was performed and he was transferred to our Ear Nose and Throat Department for further investigation. A bronchoscopic biopsy was taken of a mass occupying the tracheal lumen and intraoperative frozen section examination suggested a schwannoma, so tracheal resection was performed. Although rare, primary tracheal schwannoma should be considered in the differential diagnosis of sudden respiratory distress of unknown origin.     

Schwannoma of the Breast: Report of a Case

This report describes a rare case of a schwannoma that developed in the left breast of a 45-year-old woman without von Recklinghausens disease. The patient complained of a mass growing slowly in her breast for more than 4 years. She did not have any pain and denied any discharge from her nipple. A physical examination revealed a 3.1 × 2.3-cm, elastic-soft, smooth, and mobile lump close to the nipple of the left breast. Mammography revealed a circumscribed, oval-shaped, and equal dense nodule without microcalcification. On ultrasonography the lesion was found to be a well-demarcated, hypoechoic mass including a large cystic area, which led to the suspicion of a phyllodes tumor. An excisional biopsy was performed. A microcopic examination revealed a structure with interlacing bundles of numerous elongated spindle-shaped cells with a typical palisading pattern. These findings were compatible with schwannoma. A review of the English literature yielded 21 proven cases of breast schwannoma. In this report, we describe another such case and review those documented in the literature.     

Schwannoma of Parapharyngeal Space: a Case Report

The incidence of schwannoma in the head and neck region is between 25 and 45 %. The vestibular nerve is involved in most cases followed by the parapharyngeal space. Schwannoma, also known as neurilemmoma, is a benign neoplasm that originates from the Schwann cells. These cells form the myelin sheath around myelinated peripheral axons. Here, we report a case of parapharyngeal space schwannoma in a 27-year-old female.     

Simultaneous Bilateral Spontaneous Pneumothorax Secondary to Metastatic Angiosarcoma of the Scalp: Report of a Case

Angiosarcoma is a highly malignant neoplasm, which most often develops on the scalp or face of elderly people. Common distant metastatic sites include the lung, liver, lymph nodes, and skin. We report a case of angiosarcoma manifesting as simultaneous bilateral spontaneous pneumothorax secondary to pulmonary metastases in an 86-year-old man. The pneumothorax preceded the diagnosis of angiosarcoma. Chest computed tomography showed multiple thin-walled cavitary metastatic pulmonary lesions, which increased in size as new lesions appeared over the clinical course of several months. This case suggests that a finding of simultaneous bilateral spontaneous pneumothorax may indicate a serious parenchymal lung disorder.     

Noradrenalin-Secreting Retroperitoneal Schwannoma Resected by Hand-Assisted Laparoscopic Surgery: Report of a Case

A 66-year-old woman was admitted to our hospital for investigation of a retroperitoneal mass. She was asymptomatic but her serum noradrenalin and vanillylmandellic acid levels were increased remarkably. Computed tomographic angiography showed a mass in the left side of the superior mesenteric artery (SMA) divergence, 6 × 4 cm in size, supplied mainly by the left adrenal artery. We performed hand-assisted laparoscopic surgery (HALS) using a Cavitron ultrasonic surgical aspirator. Abdominal exploration revealed that the tumor was located in the left side of the SMA root, but was not adhered to the adjacent organs. Her vital signs remained stable during the operation. Microscopic examination revealed a palisade formation, confirming a histopathological diagnosis of degenerated schwannoma (Antoni type B). Immunohistologically, the tumor cells were stained with S-100 protein and neuron-specific enolase. Her noradrenalin level normalized immediately after the operation and she remains in good health 3 years 2 months later.     

Plexiform Schwannoma of the Small Intestine: Report of a Case

Plexiform schwannoma is a benign peripheral nerve sheath tumor composed exclusively of schwann cells arranged in a plexiform pattern. Most plexiform schwannomas are skin tumors and there has been only one case report of this tumor originating in the colon. We describe herein the first known case of plexiform schwannoma of the small intestine occurring without any relationship to schwannomatosis or neurofibromatosis. A 57-year-old man presented with a short history of abdominal pain, vomiting, and bloody stool after each meal. Jejunography demonstrated multiple nodular tumors in the small intestine. We resected the small intestine laparoscopically. The tumors consisted of multiple white nodules in the submucosal and subserosal layers. Microscopic examination revealed that each tumor was composed mainly of Antony A tissue, compatible with conventional schwannoma. Immunohistochemically, the tumors were positive for S-100, vimentin, and neuron-specific enolase, and negative for HHF35, -SMA, and c-kit. No evidence of recurrence has been found in 38 months of follow-up.     

A Case of Benign Schwannoma of the Ascending Colon Treated With Laparoscopic-Assisted Wedge Resection

Isolated colonic schwannomas are rare gastrointestinal mesenchymal tumors. Only a small number of cases have been reported. Occurrence of these tumors is more common in the stomach than in the large intestine. These spindle cell lesions are distinct from leiomyoma, leiomyosarcoma, and gastrointestinal stromal tumors because the tumor cells have a distinct immunophenotype, with strong diffuse positivity for S-100 and vimentin, as well as corroborative negative staining of CD117 and smooth muscle markers. We present a case of colonic schwannoma in a 70-year-old woman who had no specific symptoms. The patient was diagnosed with a submucosal tumor in the ascending colon on colonoscopy and abdominal computed tomography. Laparoscopic-assisted wedge resection of colon was performed. The very rare pathologic diagnosis of ascending schwannoma was made postoperatively. This case is interesting because schwannomas of the colon and rectum are extremely rare and are treated by laparoscopic-assisted wedge resection.     

The Diagnostic Dilemma of a Parasympathetic Schwannoma in the Submandibular Gland

Schwannomas are benign soft tissue tumours that arise from nerve sheath cells. They are rare in the salivary glands and are thought to arise from the parasympathetic nerves. We report the case of a 69-year-old man who presented with a painless right submandibular mass that appeared to resemble a pleomorphic adenoma on ultrasonography and, on this basis, proceeded to surgical excision of the gland. We review the relevant literature and highlight the diagnostic pitfalls.     

A Strategy of Sequential Therapy with a Bronchoscopic Excision and Thoracotomy for Intra- and Extrabronchial Wall Schwannoma: Report of a Case

A 69-year-old woman was admitted with dyspnea on effort and left lung atelectasis on chest X-ray. Fiberoptic bronchoscopy revealed a complete obstruction of the left main bronchus due to a polypoid lesion. This lesion was diagnosed to be a schwannoma arising from the left lower bronchus. Bronchoscopic treatments were performed with electrosurgical snaring and the intratumoral injection of 99.5% ethanol. These treatments were performed once per week for 4 weeks, then were followed with a one-time application of semiconductor laser cautery. These treatments opened the airway and restored the left lung expansion. However, a residual tumor remained at the bifurcation of the left basal bronchus and B6. A cautious follow-up was conducted because schwannoma is a potentially benign tumor. A follow-up bronchoscopic examination at 21 months revealed a regrowth of the residual tumor. A complete resection using a left S6 sleeve segmentectomy was thus performed. The pathologic diagnosis of the tumor was benign schwannoma. There were no complications and no evidence of disease recurrence has been observed after the surgery.     

Renal Angiosarcoma: A Case Report

We report the first case of angiosarcoma in the kidney occurring in a woman; the tumor was initially believed to be renal cell carcinoma. This malignant tumor was discovered in a patient with macrohematuria. The final diagnosis was confirmed by histologic and immunohistochemical findings. A review of the literature on this tumor is also included in the discussion.     

Oculomotor Nerve Schwannoma Associated with Acute Hydrocephalus: Case Report

A 37-year-old woman presented with an extremely rare large oculomotor schwannoma associated with acute hydrocephalus manifesting as semicoma and anisocoria. Brain computed tomography and magnetic resonance imaging revealed a tumor in the oculomotor cistern. Cerebral angiography revealed separation of the posterior cerebral artery (PCA) and superior cerebellar artery (SCA). The tumor was removed subtotally by two stage surgery. Histological examination revealed ordinary schwannoma. The diagnosis of oculomotor nerve schwannoma was based on the intraoperative finding of the tumor origin in the oculomotor nerve. Oculomotor nerve schwannoma can cause acute hydrocephalus and manifest as impaired consciousness. The angiographical separation of the PCA and SCA was very useful for the preoperative diagnosis of oculomotor nerve schwannoma.     

A rare cause of chronic sciatic pain: Schwannoma of the sciatic nerve

Schwannomas are common, benign tumors of the shelth of peripheral nerves. Sciatic schwannomas are rare. Their symptomatology usually mimics sciatic pain due to a herniated disc, which can delay the diagnosis. If there is no lumbar pain and lumbar MRI is normal, the sciatic nerve must be clinically and radiologically examined all along its course. We report a case of sciatic nerve schwannoma presenting with chronic sciatica which was diagnosed and monitored radiologically for several years before successful surgical resection.     

A parapharyngeal space schwannoma arising from the vagus nerve: A case report

IntroductionTumours of the parapharyngeal space are rare. Only 0.5% of head and neck tumours occur in this space. Surgical excision of parapharyngeal space lesions is challenging because of the anatomical complexity of the area.Presentation of caseA 31-year-old male patient was referred by his general dental practitioner for removal of lower wisdom teeth due to multiple episodes of pericoronitis. At the initial examination, an incidental finding was made of a large fluctuant posterior oropharyngeal swelling. A fluid aspirate was taken from the lesion but this was inconclusive. The patient underwent an urgent MRI and CT neck revealing a large parapharyngeal mass. An incisional biopsy of the lesion confirmed the presence of a vagal nerve schwannoma which was subsequently removed via a transcervical approach.DiscussionDue to their slow growing and painless nature, they are often not detected until they are large enough to palpate or visualise. It may cause secondary symptoms such as dysphagia, hoarseness and nasal obstruction. This case represents a typical presentation of a parapharyngeal schwannoma and reiterates the subtle and often ambiguous nature of the lesion.ConclusionVagal schwannomas in the parapharyngeal space are rare. They usually present in the form of an isolated intraoral or neck mass. A positive diagnosis is made on imaging and confirmed by histopathological examination. Complete surgical excision is the treatment of choice and recurrence rates are low.     

Frequency of Diplopia after Intraoperative Nerve Disturbance in Trochlear Nerve Schwannoma: A Case Report and Systematic Review

Schwannomas of the trochlear nerve are relatively rare, and most patients present with preoperative diplopia because of trochlear nerve palsy. We describe the case of a 61-year-old male patient with a trochlear nerve schwannoma and no pre- and postoperative diplopia, despite his trochlear nerve being cut during the operation. We aimed to investigate the frequency of postoperative diplopia associated with intraoperative trochlear nerve disturbance by reviewing previous case reports, wherein postoperative diplopia did not occur after the trochlear nerve was cut intraoperatively. We recorded the frequency of diplopia because of intraoperative trochlear nerve disturbance, such as the trochlear nerve being cut, in cases without pre- and postoperative diplopia. We searched the PubMed, Medline, and Google Scholar databases for works published from 1976 to 2020 and followed the preferred reporting items for systematic reviews and meta-analyses guidelines. We reviewed 36 publications and found 92 cases of trochlear nerve schwannoma. Surgical resection was performed for 43 patients, of whom 40 were kept under observation and 9 were treated with radiation therapy. Of the 43 cases, 9 without preoperative diplopia underwent gross total resection. We analyzed ten cases (including ours) without preoperative diplopia to check for postoperative diplopia. In total, four cases, including ours, did not display postoperative diplopia despite the trochlear nerve being cut. This may be attributed to the preoperatively acquired motor and sensory fusion in the patient’s vision because of tumor progression. Our findings may benefit neurosurgeons who treat patients with schwannomas and help them predict patients’ outcomes.     

Primary Tracheal Schwannoma: a Case Report

We present a rare case of primary tracheal schwannoma in a 49-year-old man who had experienced obstructive airway symptoms for 4 years. Computed Tomography (CT) showed an intratracheal polipoid mass lesion originating from the left lateral wall. Fibre-optic bronchoscopy revealed the diagnosis of an intratracheal poylpoid mass obstructing 70% of the lumen. After diagnosing a benign lesion by punch biopsies with bronchoscopy, thoracotomy was performed and the tumour was totally excised. Histopathological examination revealed a benign neurogenic tumour of schwann cell origin.     

Solitary Schwannoma of the Colon: Report of Two Cases

Some patients with gastrointestinal schwannoma (GIS) have been previously reported in the literature. However, GIS of the colon is quite rare. In addition, it is sometimes difficult to differentiate neurogenic tumors from other soft tissue tumors. We herein describe two cases of schwannoma of the colon, while also reviewing the relevant Japanese literature. The first case, a 73-year-old woman underwent a sigmoidectomy with lymph node dissection following the diagnosis of submucosal tumor. In the second case, a submucosal tumor was located in the cecum of a 44-year-old man. An endoscopic tumor resection was performed in the second case. The resected tumors measured 3.6 and 1.0 cm in maximal diameter, respectively. Microscopically, the tumors consisted predominantly of spindle-shaped cells that proliferated in an interlaced fashion. Mitosis was rarely seen in these tumors. Immunohistochemically, the tumor cells were strongly positive for S-100 protein, weakly positive for glial fibrillary acidic protein, and negative for CD34, α-smooth-muscle actin, and cytokeratin (CAM 5.2) in both cases. The tumors in the two cases were both diagnosed to be benign schwannoma of the colon. In general, schwannoma of the gastrointestinal tract is considered to be benign and should therefore be distinguished from other spindle-cell tumors or malignancies. Once diagnosed as schwannoma, extensive surgery should be avoided. Actually, such patients tend to show a good postoperative course with no evidence of recurrence. Received: November 2, 2000 / Accepted: May 15, 2001     

Esophageal Schwannoma: Report of a Case

We report a case of esophageal schwannoma in a 46-year-old woman who presented with rapidly progressive dyspnea and dysphagia. Chest computed tomography showed a large mediastinal mass, which was extrinsically compressing the trachea, widely adjacent to the upper thoracic esophagus. We performed an axillary right thoracotomy to enucleate the tumor, which was located in the esophageal muscle layer. A definite diagnosis of esophageal schwannoma was made from the pathologic findings, which included positive immunohistochemical staining for S-100 protein and negative staining for c-kit and CD34.     

Hepatic Angiosarcoma Post-Renal Transplantation: A Case Report

BackgroundDNA damage and oncogenic viruses increase the risk of cancer post-kidney transplantation, including skin cancer, Kaposi's sarcoma, oral cancer, and non-Hodgkin lymphoma. Here we report an uncommon case of liver angiosarcoma that occurred 8 years after kidney transplantation. This study strictly complied with the Helsinki Congress and the Istanbul Declaration regarding donor source.Case reportA 57-year-old female patient received a cadaver kidney transplantation 8 years ago. She followed a long-term regimen of tacrolimus, mycophenolate sodium, and everolimus, with good renal function. She received annual regular abdominal ultrasound examinations after kidney transplantation, which showed no findings. The patient suffered from several symptoms for approximately 2 weeks before a scheduled abdominal ultrasound: diarrhea, epigastric pain, abdominal fullness, tea-colored urine, and little stool passage. The abdominal computerized tomography showed multiple hepatic tumors in both the hepatic lobes with engorged vasculatures and mild hemoperitoneum. A liver biopsy revealed the histopathology of angiosarcoma. The patient suffered multiple organ failure within one month of treatment.ConclusionsVarious post-transplant malignancies are not uncommon after transplantation, warranting periodic screenings for any symptoms in these patients.