• Journal of Korean Neurosurgical Society
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• 제42권3호
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• pp.159-167
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• 2007

Vestibular schwannoma (VS) is a benign tumor typically originated in the schwann cell of vestibular nerve and usually accompany hearing symptom. Microsurgical removal and radiosurgery have a great role for the treatment of VS. Recently radiosurgery has been considered as an alternative or primary treatment for VS with the tremendous increase of patients who were treated with gamma knife radiosurgery (GKS) though microsurgery still takes the premier. By many published results, it is proved that GKS is a effective and noninvasive technique for VS, especially small sized tumors with satisfactory tumor control rate. The authors assumed that GKS can be expected to achieve satisfactory tumor control rate for small VS under 5cc in volume. A major interest regarding radiosurgery nowadays is to determine the optimal radiation dose for hearing preservation to improve the quality of life of patients. The more high radiation dose are used for effective tumor growth control, the more radiation-related complications like as hearing deficit, the impairment of other cranial nerve function are increased. Since 1990's the mean radiation dose for tumor margin was more than 18 Gy, but there were high complication rate in spite of good tumor growth control. After the year of 2000, under the influence of advanced neuro-imaging techniques and radiosurgical planning system which enable clinicians to do more precise planning, marginal dose for VS has been decreased to 12-13 Gy and the radiation-related complications has been reduced. But because there may be a unexpected radiation induced complications as time goes by after the latency period, optimal radiation dose for VS should be established on the basis of more long term follow-up observation.

• 대한골관절종양학회지
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• 제4권2호
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• pp.88-93
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• 1998

Neurilemoma usually discovered incidentally, is a benign nerve-sheath tumor which has been described as a painless mass. In most cases, the size of the mass was smaller than 5cm. However, it was reported that there were masses, sometimes associated with local tenderness and pain, whose size was over 6cm. Then, we have found there is a relationship between mass size and neurologic symptoms, as well as with, postoperative complications. It is important to diagnose early and to treat it. Twenty neurilemoma patients, who were treated at Keimyung University Dongsan Medical Center were analyzed using their clinical symptoms, pathologic findings, radiologic findings and complications. There was no sexual difference in tumor incidence. The anatomical locations of tumors were as follows. ; upper extremities in 15 cases(69%), axilla in 1 case(4%) and lower extremities in 6 cases(27%). Symptoms were palpable mass in 22 cases, local tenderness in 8 cases(36%), radiating pain in 6 cases(27%) and paresthesia in 6 cases(27%), Median nerve was involved most frequently(33%). There were 2 patients(10%) with multiple symptoms. Tumor enucleation was done in all cases. The size of tumors in longest axis was smaller than 2cm in 2 cases, between 2 and 4cm in 11 cases and more than 5cm in 9 cases. There was no case of malignant transformation or recurrence. In conclusion, incidence of clinical symptom and postoperative complications are increased with the size of the tumor especially over the 5cm. Preoperative MRI finding was the most accurate method of diagnosis and most helpful in determining surgical resection margin.

• 대한두경부종양학회지
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• 제37권2호
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• pp.51-55
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• 2021

Background/Objectives: Extracapsular dissection has the advantage of reducing complications by minimizing tissue loss of the parotid without intentionally exposing the facial nerve in patients with benign parotid tumor. However, there has been controversy over the surgical results. Thus, the surgical outcomes of extracapsular dissection for benign parotid tumor was compared to those of superficial parotidectomy. Materials & Methods: A retrospective chart review was conducted with 132 patients who received surgery for benign parotid tumor in our center from January 2014 to December 2018 retrospectively. Results: A total of 132 people were enrolled, with 62 people receiving extracapsular dissection, 38 people receiving partial superficial parotidectomy and 32 people receiving superficial parotidectomy. No significant difference was found between the three groups regarding complications such as facial nerve palsy, Frey's syndrome, or first bite syndrome. Operation time and hospital stay was significantly short in extracapsular dissection group. Conclusion: For well-selected cases, extracapsular dissection can be considered as an option for surgery of benign parotid tumor.

• Archives of Plastic Surgery
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• 제36권6호
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• pp.799-802
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• 2009

Purpose: Schwannoma is one of common neoplasm in the central and peripheral nervous systems. However, schwannoma of sciatic nerve is rare, especially large schwannoma arising in sciatic nerve is extremely rare. This is a report of our experience with large schwannoma arising in sciatic nerve with minimal neurologic symptoms. Methods: A 65 - year - old man presented with palpable mass in middle portion of posterior thigh. No definitive neurologic deficits were detected on physical examinations. CT and sonography showed well - defined mass with large dimension. The mass was excised and confirmed histologically as a schwannoma. In postoperative period, NCS and EMG were followed. Results: The patient complained of difficulty in dorsiflexion of ipsilateral ankle joint postoperatively. NCS and EMG obtained immediately and showed sciatic neuropathy. After 2 months postoperatively, NCS and EMG were followed and abnormal findings of previous NCS and EMG were not found. Dorsiflexion of ankle joint was improved to normal range of motion. Conclusion: We report a rare case of large schwannoma arising in sciatic nerve with no definitive neurologic symptoms.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권5호
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• pp.415-423
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• 2005

Distraction osteogenesis (DO) is frequently used technique in reconstruction of bony defects resulted from tumor resection, congenital deformity, and trauma in the maxillofacial region. Although the histologic and ultrastructural changes associated with distraction osteogenesis have been extensively described, the exact changing of the surrounding tissues, such as nerve tissues, were still unclear. This study observed the histological changes and the expression of nerve growth factor (NGF) in the inferior alveolar nerve (IAN) after distraction osteogenesis. Unilateral mandibular distraction (0.5 mm twice per day for 10 days) was performed in eight mongrel dogs. Two animals were sacrificed at 7, 14, 28 and 56 days after completion of distraction, respectively. The distracted IAN and contralateral control nerve were harvested and processed for histological and innunohistochemical examinations. The signs of acute nerve injuries, such as demyelination and partial discontinuation of nerver fiber, were observed in the distracted IAN on 7 and 14 days after distraction. The initial remyelination and regeneration of distracted IAN were showed at 14 days after completion of distraction. At 56 days later, the histologic features of distracted IAN was similar to those of the normal control IAN. The expression of NGF was significantly increased in most distracted nerve tissues on 7, 14 and 28 days after distraction. On 56 days after distraction, the expression of NGF returned to the normal level. This study suggested that the acute IAN injury caused by mandibular distraction were mostly recovered during consolidation period. The NGF was seemed to be induced from Schwann cell and damaged nerve tissues, and it may have important roles in the initial healing of damaged nerves.

• Journal of Chest Surgery
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• 제26권5호
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• pp.395-402
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• 1993

For the purpose of evaluation of clinical characteristics and histopathological properties in mediastinal tumor, and to provide the guidelines of surgical management of mediastinal tumor,238 patients with mediastinal tumors treated during the period from January 1983 to December 1991 were reviewed at Seoul National University Hospital. There were 106 males & 132 females, and their ages ranged from 3 months to 73 years, with average 33.6 years. The most frequently encountered tumor site was anterosuperior mediastinum followed by posterior, and middle mediastinum. In the pathological viewpoint, thymoma was the most frequent type followed by neurogenic tumor. 81% of the tumor were benign and 19% were malignant. Half of the malignant tumors were neurogenic tumors. Malignancy rate was high in pediatric patients compared to adults as 40% and 19% respectively. 65% of patients were asymptomatic at diagnosis.There was no operative mortality. Post operative complications were occurred in 35 cases. Most frequent complications were adjacent peripheral nerve injuries. But other usual operative complications, such as bleeding, chylothorax, infection, were relatively rare.

• Journal of Korean Neurosurgical Society
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• 제47권1호
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• pp.64-67
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• 2010

Although very rare, a few cases of intradural extramedullary (IDEM) spinal tumor migration have been reported since Tomimatsu first reported a mobile schwannoma of the cervical cord in 1974. Schwan noma is a neurogenic tumor which originates from nerve sheath that it is relatively well-marginated tumor with little attachment or adhesion to surrounding tissue. Mobility of tumor in spinal canal sometimes can result in negative exploration at the expected area. We found three interesting cases in which different tumor locations observed in repeated magnetic resonance image (MRI) findings. All tumors were intradural and extramedullary schwannoma. We reviewed the literature about moving tumor in the spine through PUBMED search.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권4호
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• pp.271-281
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• 2004

Adenoid cystic carcinoma is malignant tumor in salivary gland, and its behavior is very invasive. Of all malignant tumor adenoid cystic carcinoma is occured in frequency of 4.4% in major salivary gland, and 1.29% in minor salivary gland. Histopathologically, adenoid cystic carcinoma is characterized by a cribriform appearance, and tubular form and solid nest type tumor can be seen. The tumor cell structure composed of modified myoepithelial cell, and basaloid cell. Extracellular matrix of this tumor cell contains variable ground substance with basement membrane component. Basement membrane matrix composed of collagen fibers, glycoproteins, proteoglycans, and its function is well known that it participate in differentiation, proliferation, and growth of tumor cell. Basement membrane molecule is essential for invasion of peripheral nerve, blood vessel, skeletal muscle in tumor cell of adenoid cystic carcinoma. In many studies, the tumor cell of adenoid cystic carcinoma containing modified myoepithelial cell participate in synthesis of proteoglycan. In this study, tissue sample of adenoid cystic carcinoma of human salivary gland were obtained from 15 surgical specimen, and all specimen were routinely fixed in 10% formalin and embedded. Serial $4-{\mu}m$ thick sections were cut from paraffin blocks. the histopathologic evaluation was done with light microscopy. And, the immunohistochemical staining, characteristics of glycosaminoglycan were observed. For biochemical analysis of glycosaminoglycan, isolation of crude glycosaminoglycan from tumor tissue and Western bolt analysis were carried out. With transmission electomicroscopy, tumor cell were observed. Biologic behavior of adenoid cystic carcinoma was observed with distribution and expression of basement membrane of glycosaminoglycan in tumor cells, The results obtained were as follows: 1. In immunohistochemical study, chondroitin sulfate is postively stained in tumor cell and interstitial space, dermatan sulfate is weakly stained in ductal cell. But keratan sulfate is negatively stained. 2. In immunohistochemical study, heparan sulfate is strong positive stained in tumor cell and basement membrane, especially in invasion area to peripheral nerve tissue. 3. In transmission electromicroscpic view, the tumor cells are composed modifed myoepithelial cells, and contains many microvilli and rough endoplasmic reticulum. 4. In Western blot analysis, the expression of glycosaminoglycan is expressed mostly in heparan sulfate. From the results obtained in this study, tumor cell of adenoid cystic carcinoma is composed modified myoepithelial cell, and glycosaminoglycan of basement membrane molecule of heparan sulfate and chondroitin sulfate mostly participate in the development and invasiveness of adenoid cystic carcinoma by immunohistochemical study and western blot analysis.

• 대한두경부종양학회지
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• 제28권2호
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• pp.125-128
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• 2012

Salivary duct carcinoma(SDC) is a highly malignant tumor of the salivary gland. The tumor is clinically characterized by a rapid onset and progression, the neoplasm is often associated with pain and facial paralysis. The nodal recurrence rate is high, and distant metastasis is common. SDC resembles high-grade breast ductal carcinoma. Curative surgical resection and postoperative radiation were the mainstay of the treatment. If facial paralysis is present, a radical parotidectomy is mandatory. Regardless of the primary location of SDC, ipsilateral functional neck dissection is indicated, because regional lymphatic spread has to be expected in the majority of patients already at time of diagnosis. If there is minor gland involvement, a bilateral neck dissection should be performed, because lymphatic drainage may occur to the contralateral side. The survival of SDC patient is poor, with most dying within three years. We experienced a unique case of SDC in parotid deep lobe. We report the clinicopathologic features of this tumor with a review of literature.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제42권5호
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• pp.288-294
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• 2016

Chondrosarcoma is a malignant tumor that originates from cartilaginous cells and is characterized by cartilage formation. Only 5% to 10% of chondrosarcoma occurs in the head and neck area, and it is uncommon in the temporomandibular joint area. This report describes an unusual case with a rare, large chondrosarcoma in a 47-year-old woman who presented with painless swelling and trismus. Computed tomography showed a large mass approximately $8.5{\times}6.0$ cm in size arising adjacent to the lateral pterygoid plate and condyle. There were features suggestive of bone resorption. The tumor was resected in a single block with perilesional tissues, and a great auricular nerve graft was performed because of facial nerve sacrifice. Microscopic examination of sections stained with H&E revealed chondrocytes with irregular nuclei and heterogeneous hyper chromatic tumor cells embedded in the chondrocyte lacuna. The diagnosis was a grade I chondrosarcoma. There was no evidence of recurrence at the 8-month follow-up, and a reconstruction surgery with fibular osteocutaneous free flap was performed. We report this unusual entity and a review of the literature.