• Journal of Korean Neurosurgical Society
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• v.29 no.5
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• pp.701-705
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• 2000

Solitary plasmacytomas are rare and account for 5-10% of all plasma cell disorders. These tumors are categorized as solitary plasmacytomas of bone(osseous) or extramedullary plasmacytomas(non-osseous). About a half of solitary plasmacytomas of bone occur in the spine but rarely in the skull. We report a case of solitary plasmacytoma of the skull presented with a painless palpable left parietal calvarial mass in an otherwise asymptomatic 38- year-old man. Skull radiographs showed a large radiolucent lesion with well defined non-sclerotic margins. Computed tomograph scan demonstrated a markedly enhancing mass extending from the epidural to the subcutaneous space. The patient underwent surgery and tumor was completely excised. Pathological examination showed tumor to be a plasmacytoma synthesizing IgG. Postoperatively, the patient received radiotherapy. There was no evidence of systemic involvement on postoperative laboratory wokups. Our recommended treatment is a complete surgical excision combined with postoperative radiation therapy. The patient should be follwed carefully for more than 10 years because of either local recurrence or possible progression to multiple myeloma.

• Archives of Plastic Surgery
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• v.36 no.1
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• pp.96-100
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• 2009

Purpose: Angiosarcoma of the scalp is unusual vascular tumor originating from endothelial cell. Angiosarcoma is an aggressive tumor with high propensity for both local recurrence and distant metastasis. We report 2 cases of angiosarcoma having poor prognosis recently. Methods: Case 1 was a 67 - year - old male patient. He visited the hospital with a $3{\times}5cm$ sized discolored mass in forehead. It began at one month ago from coming to the hospital. Case 2 was a 64 - year - old male patient. He visited for our hospital to remove a $4{\times}5cm$ sized scalp mass. He had a pruritis on scalp from 9 months ago before coming to the hospital. Despite of the conservative treatments, the wound was not healed and advanced necrotic lesion with hemorrhage. Results: Case 1 diagnosed as an angiosarcoma. He underwent a radical operation 5 times. But the tumor expanded multiple area in dura & frontal area of the brain. The patient rejected the treatment any more. And he died one month later. Case 2 diagnosed as an angiosarcoma and metastased to skull in MRI. He got a radical resection including cranium. Three months later, it recurred to ipsilateral Sternocleidomastoideus muscle. He got a additional operation & started radiotherapy. And now he is receiving chemotherapy, but the recurred lesion is expanding. Conclusion: Angiosarcoma is a highly malignant tumor. Especially it arises in vascularized area, it easily metastases. So it is the best to treat angiosarcoma with surgery included wide margins. Despite of the lesion is small, we remember that angiosarcoma is a tumor that consider to metastases.

• Archives of Plastic Surgery
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• v.32 no.6
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• pp.760-762
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• 2005

Synovial Sarcoma is the fourth most common sarcoma, accounting for 8-10 % of all sarcomas. Synovial sarcoma is highly malignant tumor of mesenchymal origin but rarely occurres in head and neck area. Less than 100 cases of synovial sarcoma occurring in head and neck area have been reported all over the world. Pathologically, there is two type of synovial sarcoma: monophasic variant is composed of only one cell type and "classic" (biphasic) synovial sarcoma has two cellular component, a spindle cell(fibrosarcoma-like) component and a pseudoepithelioma component. Recommended treatment is wide resection with negative margins. The role of chemotherapy and radiation therapy is controversial. We experienced a 42-year-old male patient with slowly enlarging, deep seated mass on right cheek. In the first operation, we suggested that the mass maybe benign tumor. But, initial excisional biopsy specimen of the primary lesion was consistent with synovial sarcoma. The final diagnosis was monophasic synovial sarcoma which was composed of spindle cells. Radical resection was performed two months later because remnant tumor was found on follow up MRI. No further treatment was done. There were no recurrence or metastasis on follow up MRI, chest CT and whole body bone scan after 15 months. This is a report of a rare case of synovial sarcoma of the face with a literature review.

• The Korean Journal of Applied Statistics
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• v.29 no.2
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• pp.369-379
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• 2016

The Sigma Level, proposed by Motorola Inc., is one of the many Process Capability Index (PCI)'s that have been presented since the 1970's. It is used to evaluate process capability and unlike other PCI's, it has an advantage in that it uses population probability distribution. However, it is originally designed for mass production and is inadequate to evaluate prototypes or early products in the R&D stages. For use in such cases, we propose an R&D target Sigma Level, derived by considering 1.5 sigma shifts in traditional sigma level from a statistical point of view. We also explain the way to find robust limits for design tolerance because the sigma level or defect probability is useful to establish economical tolerance limits at the R&D stage and mass production.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.501-504
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• 2011

Purpose: Epithelial-myoepithelial carcinoma (EMC) represents about the 1% of the malignant neoplasms in the salivary glands and clinically most commonly found localized, well defined and sometimes presents orofacial pain. Treatment of choice is surgical excision. Postoperative radiotherapy can be used when surgical margins are doubtful. We report our experience of EMC of the parotid gland. Methods: A 78-year-old man presented with a three-year history of a localized, painless, $7{\times}6cm$ sized recurred tumor in his right preauricular area. He was diagnosed as EMC of the right parotid gland. So a total parotidectomy was performed. In his old medical history, he had a mass in the same area 5 years ago. The diagnosis of pleomorphic adenoma was made and the mass excision was performed at the local clinic without further evaluation. Results: It was unable to visually discriminate between the tumor and the normal tissue. So a total parotidectomy was performed. The patient was got post-operative radiotherapy and was followed up for 9 months. There was no specific evidence of recurrence. Conclusion: We present a case of EMC of the parotid gland in right preauricular area, which is uncommon. So we report a uncommon case of EMC to discuss about our experience with relevant journal discussion.

• Journal of Yeungnam Medical Science
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• v.31 no.2
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• pp.131-134
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• 2014

Familial isolated primary hyperparathyroidism(FIPH) is associated with multiple endocrine neoplasia type 1 (MEN1) syndrome, primary hyperparathyroidism accompanied by jaw-tumor syndrome, and familial hypocalciuric hypercalcemia. FIPH may be an early stage of MEN1 or an allelic variant of MEN1. Thymic carcinoid tumor is a rare tumor in MEN1 syndrome. Here, the authors report the case of a 40-year-old man diagnosed with recurrent thymic carcinoid tumor and FIPH. Both the patient and his elder sister had been previously diagnosed to have FIPH with a novel frameshift mutation in the MEN1 gene. Initially, the patient underwent thymectomy because of an incidental finding of a mediastinal mass in his chest X-ray, and had remained asymptomatic over the following 4 years. Pancreas computed tomography conducted to evaluate MEN1 syndrome revealed anterior and middle mediastinal masses, and resultantly, massive mass excision was performed. Histological findings disclosed atypical carcinoids with infiltrative margins. In view of the thymic carcinoid tumor relapse that occurred in this patient, the authors recommend that regular pancreas and pituitary imaging studies be conducted for FIPH associated with a MEN1 gene mutation.

• Journal of Veterinary Clinics
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• v.31 no.2
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• pp.152-155
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• 2014

An 11-year-old castrated Schnauzer presented with paraplegia for the last two weeks, initially developed pelvic limb ataxia 6 months ago and left pelvic limb paresis 3 months ago. On neurological examination, paraplegia and postural reaction deficits were noted in the pelvic limbs with no deep pain sensation, and the dog showed exaggerated spinal reflexes and involuntary urination. Magnetic resonance (MR) images of thoracolumbar spinal cord were obtained with a 0.3 Tesla magnet. A mass with a broad base to the dorsal and left dural margins was identified at the level of L2, causing marked spinal cord compression. The mass showed isointensity to the spinal cord on T1-weighted (T1W) precontrast images, hyperintensity on T2-weighted images, marked homogeneous contrast enhancement with well-defined margins and the "dural tail" sign on T1W postcontrast images. An intradural-extramedullay tumor was considered, most likely, meningioma was highly suggestive. Left-sided hemilaminectomy and dorsal laminectomy were performed. An intradural mass partially adherent to dura mater was compressing the spinal cord, and the mass was completely removed with the attached dura mater. A histopathologic diagnosis of angiomatous subtype meningioma was made.

• Investigative Magnetic Resonance Imaging
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• v.20 no.3
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• pp.158-166
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• 2016

Purpose: To understand clinical significance of irregular interface between meningioma and adjacent brain parenchyma in predicting histological grading of tumor, focusing on brain parenchymal invasion. Materials and Methods: Pathologically confirmed 79 cases with meningiomas with pathological reports about the presence of parenchymal invasion were included. We defined the presence of interface irregularity as either spiculations or fuzzy margins between the tumor and brain parenchyma. We counted number of spiculations and measured ratio of fuzzy margin length to whole length of mass with consensus of two neuroradiologists. We classified the patients into Present group and Absent group, and the two groups were compared by using the Mann-Whitney U test. Statistical correlations between the presence of an interface irregularity and brain parenchymal invasion by the tumor as well as meningioma histological grade were tested with chi-square test. The optimal cutoff values of spiculation numbers and the ratio of fuzzy margins were determined. The sensitivity and specificity of number of spiculations, ratio of fuzzy margin and the presence of irregular interface as combined parameters for predicting the parenchymal invasion were calculated using ROC curve analysis. Results: Statistically significant differences were noted between the Present and Absent groups for number of spiculations and ratio of fuzzy margin (P = 0.038 and P = 0.028, respectively). The optimal cutoff value for number of spiculations (> 4.5 with 61.1% sensitivity and 68.9% specificity) and the ratio of fuzzy margin (> 0.24 with 66.7% sensitivity and 65.6% specificity) were determined. The sensitivity and specificity of interface irregularity as the combined parameters were 72% and 59%, respectively. The interface irregularity between tumor and brain parenchyma significantly correlated with not only brain parenchymal invasion (P = 0.001) and but also histological grade (P < 0.001). Conclusion: The interface irregularity between tumor and brain parenchyma in MRI can be a strong predictive factor for brain parenchymal invasion and high grade meningioma.

• Journal of Astronomy and Space Sciences
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• v.23 no.4
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• pp.355-372
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• 2006

Mission opportunities and trajectory characteristics for the future Korean Mars mission have designed and analyzed using KSIV-III(Korea Space Launch Vehicle-III). Korea's first space center, 'NARO space center' is selected as a launch site. For launch opportunities, year 2033 is investigated under considering the date of space center's completion with KSLV series development status. Optimal magnitude of various maneuvers, Trans Mars Injection (TMI) maneuver, Trajectory Correction Maneuver (TCM), Mars Orbit Insertion (MOI) maneuver and Orbit Trim Maneuver(OTM), which are required during the every Mars mission phases are computed with the formulation of nonlinear optimization problems using NPSOL software. Finally, mass budgets for upper stage (launcher for KSIV-III and spacecraft are derived using various optimized maneuver magnitudes. For results, daily launch window from NARO space center for successful Korean Mars mission is avaliable for next 27 minutes starting from Apr. 16. 2033. 12:17:26 (UTC). Maximum spacecraft gross mass which can delivered to Mars is about 206kg, with propellant mass of 109kg and structure mass of 97kg, when on board spacecraft thruster's Isp is assumed to have 290 sec. For upper stage, having structure ratio of 0.15 and Isp value of 280 sec, gross mass is about 1293kg with propellant mass of 1099kg and structure mass of 194kg. However, including 10% margins to computed optimal maneuver values, spacecraft gross mass is reduced to about 148kg with upper stage's mass of 1352kg. This work will give various insights, requiring performances to developing of KSIV-III and spacecraft design for future Korean Mars missions.

• The Journal of the Korean bone and joint tumor society
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• v.1 no.2
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• pp.205-209
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• 1995

A desmoid tumor is a locally aggressive growth of connective tissue origin which infiltrates the surrounding tissue and has a marked tendency for recurrence. And so it was also called as an aggressive fibromatosis, musculofascial fibromatosis or fibrosarcoma etc. Thirteen cases of desmoid tumor was treated since 1980, and their retrospective study was done with 79 months of follow-up after initial surgical excision. The female was involved in 12 cases(one male) with the age ranged from 7-50 years, average 28 years, and seven patients in third decade. A slowly growing mass was excised on average 4 months after first notice of the mass, but their margins are not demarcated clearly in most cases. Wide excision in 12 cases was done, but wide excision and saphenous vein graft was performed in one case because of invasion of posterior tibial artery by tumor mass. The tumor was found on extraabdominal region in 8 cases(61.5%) but 5 cases in abdominal wall(38.5%). The recurrence rate was high(6/13, 46.2%), and 11 times in 6 patients were recurred(average 1.8 times), within 27 months of initial excision. Six cases of recurrence were treated with wide excision again in 3 cases, wide excision combined with radiotherapy(4,000-6,000cGy) in 4 cases and wide excision with chemotherapy in one case. During the follow-up for average 21 months after treatment, no recurrences are found. Tumor remission periods without recurrence are average 67 months in all, and 11 years in longest case. Histologically it was very mimic with fibrosarcoma but could be differentiated with Trichrome stain, and their findings are not changed after recurrence.