• Journal of Gastric Cancer
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• v.4 no.4
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• pp.268-271
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• 2004

Purpose: Most gastrointestinal stromal tumors (GISTs) have gain-of-function mutations of the KIT or the platelet-derived growth factor receptor alpha (PDGFRA) genes, but approximately $10\%$ of the GISTs are wild types for both the KIT and the PDGFRA genes. The purpose of this study was to investigate the possibility that epidermal growth factor receptor (EGFR) gene mutation might be responsible for the pathogenesis of GIST. Materials and Methods: We analyzed the EGFR gene in 60 GISTs for the detection of somatic mutations by using the polymerase chain reaction (PCR), the single strand conformation polymorphism (SSCP), and DNA sequencing in exon 18, 19, and 21 encoding the kinase domain. Results: The SSCP analysis revealed no evidence of EGFR mutations in exon 18, 19, and 21 in GISTs. Conclusion: The data indicate that the EGFR gene may not be mutated in human GIST and suggest that therapies targeting the mutated EGFR gene products might not be useful in the treatment of GISTs.

• Journal of Chest Surgery
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• v.36 no.2
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• pp.109-112
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• 2003

Stromal tumors of the gastrointestinal tract, especially of the esophagus, are rare. We had a case of malignant gastrointestinal stromal tumor(GIST) of the esophagus. A 46 years old woman was admitted for abnormal mass shadow in the chest radiograph. The mass was originated from the lower thoracic esophagus, and compressed the right lower pulmonary vein and the inferior vena cava. We removed the tumor externally without injuring of the esophageal mucosa via right posterolateral thoracotomy. The tumor was positive for CD 34 and CD 117, and diagnosed malignant CIST of the esophagus.

• Journal of Gastric Cancer
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• v.6 no.3
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• pp.146-153
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• 2006

Purpose: Gastrointestinal stromal tumorsm (GISTs) are the most common mesenchymal tumors that arise anywhere in the tubular GI tract. The prognosis for GSTIs is important because f GISTs may metastasiwx in the liver or the abdominal cavity in an early stage. For the reason we examined the tumor size, the mitotic number, ki 67, p53, and c-kit mutation as independent prognostic factor for GISTs. Materials and Methods: A retrospective study was conducted in 76 patients who had been re-evaluated for confirmation of diagnosis between Jan 1998 and Dec. 2001. at Catholic University of medicine. Results: There were significant difference between the turner size, mitotic indices, ki 67, c-kit mutations and the 5-years survival rates. Tumor size (${\geq}5\;cm$) and mitotic index (${\geq}5/50\;HPF$) were statistically related to a significantly poor prognosis (P=0.017 and P=0.042, respectively). c-kit mutations in exon 11 were found in 7 cases c-kit mutation was observed more frequently in high risk patients, and there was a significant difference between c-kit mutation and survival (P=0.037). Elevated ki 67 was noted in 34 out of the 76 cases. High risk patients showed elevated ki67 index more frequently and there was significant relation with the survival rate (P=0.0417). Conclusion: We think that tumor size, mitotic index, Ki 67 and c-kit mutation are as independent prognostic factors for GISTs, but more research is needed.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.46-51
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• 2008

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasm of the gastrointestinal tract, and can be distinguished from the smooth muscle or neural tumors in approximately 95% of patients by expression of the KIT receptor tyrosine kinase (CD117). GISTs are known to have high malignant potential and none can be labeled definitely as benign. However, GISTs are unresponsive to standard sarcoma chemotherapy, and only complete surgical resection provides chance for cure. Although the imaging modality of choice is enhanced CT scan in patients with GIST, FDG PET can reflect the malignant potential of GIST. Clinical management of patients with GISTs has dramatically changed with the introduction of novel therapeutics, such as imatinib mesylate (Glivec). This has created a need to re-evaluate the existing criteria used to assess treatment response. FDG PET as functional imaging modality proved to be significantly more accurate than CT alone when assessing GIST response to imatinib. And, FDG PET and PET ICT have been found to be highly sensitive in detecting early response, and to be useful in predicting long-term response to imatinib in patients with recurrent or metastatic GISTs.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.10 no.1
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• pp.71-75
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• 2007

Gastrointestinal stromal tumors (GISTs) are the most common primary mesenchymal tumors of the digestive tract. They have been commonly observed in adults but have been rarely described in children. They arise typically from the intestinal wall and rarely in the mesentery, omentum, or retroperitoneum. GISTs originate from the interstitial cell of Cajal and are characterized by overexpression of the receptor tyrosine kinase c-kit. Up to 94% of these tumors express the CD117 on immunohistochemical stain. Surgery is the main modality of treatment for primary resectable GIST. Completely resectable GIST with low risk has excellent prognosis after primary surgical intervention, with over 90% of the 5-year survival. We report a case of 10-year-old girl presenting with an upper gastrointestinal bleeding caused by gastrointestinal stromal tumor.

• Journal of Yeungnam Medical Science
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• v.23 no.1
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• pp.131-137
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• 2006

Small bowel tumors have been difficult to diagnose because of low incidence and absence of specific symptoms. There are no efficient and accurate tests available for diagnosis. Capsule endoscopy is an efficient diagnostic tool for small bowel disease and obscure gastrointestinal bleeding. We diagnosed two cases of small bowel gastrointestinal stromal tumor (GIST) diagnosed by capsule endoscopy that were treated by surgery. A 68 year old male presented with abdominal pain. The capsule endoscopy showed fungating ulcer mass at the jejunum. A 55 year female presented with melena. The capsule endoscopy showed an intraluminal protruding mass with a superficial ulcer at the jejunum. Two cases were diagnosed with GIST after surgery. We report these two case diagnosed by capsule endoscopy and review the medical literature.

• Journal of Digestive Cancer Research
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• v.1 no.2
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• pp.100-103
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• 2013

A 79-year-old man was diagnosed with gastrointestinal stromal tumor (GIST) of the gastric cardia. We performed proximal subtotal gastrectomy and started imatinib therapy as adjuvant treatment after surgery. Whole body skin rash with urticaria was onset on 10 days after imatinib treatment, and the patient decided to stop imatinib because of side effect. After 3 months, PET CT revealed GIST was recurred at spleen and abdominal lymph nodes, abdominal wall. The patient was then restarted on imatinib therapy. On follow-up imaging studies, the tumor almost disappeared, but both pleural effusion and pericardial effusion were found. In this paper, we describe a case of clinical course and side effects in recurred GIST after adjuvant imatinib mesylate treatment.

• Journal of Yeungnam Medical Science
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• v.23 no.1
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• pp.45-51
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• 2006

Background: This study was conducted to evaluate the usefulness of capsule endoscopy (CE) for the diagnosis of small bowel diseases. Materials and Methods: We reviewed the medical records of 66 patients (mean age: 52.1 years, male/female: 39/27), who underwent CE at Yeungnam University Hospital from August 2003 to March 2006. Results: Suspicious gastrointestinal (GI) bleeding presenting as anemia or history of gross bleeding was the most common reason to perform CE (71.2%). Other indications included GI symptoms (21.2%) such as abdominal pain/discomfort, nausea, diarrhea, and others (7.6%). In studies performed for GI bleeding (n=47), ulcer/erosion was the most common finding (n=22, 46.8%) followed by tumor (n=5, 10.6%), angiodysplasia (n=3, 6.4%), polyp (n=3, 6.4%), active bleeding (n=1, 2.1 %), ulcer with stenosis (n=1, 2.1%), and normal findings (n=12, 25.5%). Of these, a bleeding focus was detected in 32 cases (68.1%) undergoing CE studies. Among 14 patients with GI symptoms, only two patients had typical findings related with symptoms. Surgical resection was performed in five cases with tumor. Of these, four were diagnosed as gastrointestinal stromal tumor and the other one was a lymphangioma. There were no complications associated with the CE procedure. Conclusion: Capsule endoscopy is a safe, noninvasive diagnostic tool for small bowel diseases and may be useful for the diagnosis of small bowel hemorrhage including obscure bleeding. However, further studies are needed to confirm its utility for abdominal symptoms other than hemorrhage because of the low diagnostic yield.

• Journal of Yeungnam Medical Science
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• v.30 no.2
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• pp.105-108
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• 2013

Type 1 neurofibromatosis (von Recklinghausen's disease, NF-1) is an autosomal-dominant neurocutaneous-disorder characterized by systemic cafe'-au-lait spots, multiple cutaneous neurofibromas, axillary or inguinal freckling, and Lisch nodules (pigmented iris hamartomas). Approximately 10-25% of NF1 patients have gastrointestinal neoplasms. Gastrointestinal stromal tumor (GIST) in patients with neurofibromatosis is most commonly found in the small bowel and the stomach, and approximately 60% of such patients have multiple tumors or multiple tumor sites. Although, the increased incidence of GIST in patients with neurofibromatosis is well documented in pathology literature in English, but has rarely been documented in Korea. Here, we report a case of multiple GISTs in a 48-year-old woman accompanied by NF1. She was admitted to Yeung-nam University Hospital with complaints of melena and dyspnea. A contrast-enhanced computed tomography (CT) scan revealed that multiple soft tissue masses were occupying the entire peritoneal cavity. An ultrasonogram- guided biopsy was performed and the tumors were found to have been composed of tumor cells that were positive for c-kit protein. The patient was put on Imatinib mesylate treatment, and further follow-up will be carried out.

• Journal of the Korean earth science society
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• v.26 no.1
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• pp.93-105
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• 2005

Climatological characteristics in the variation of soil temperatures in Korea were investigated using Korea Meterological Administration's observation data. And the impacts of soil moisture on the variation of soil temperature were examined using observed precipitation data. The climatological averages of soil temperatures are ranged from 14.4 to $15.0^{\circ}C$ regardless of depths. And they showed an latitudinal gradient with a warm temperature at the southern region and 'U' shape as in the air temperature with a high value along the coastal region. The relatively higher heat capacity and low conductivity of soil compared to those of the air resulted in the significant delay of the maximum and minimum date with depth. As a results, soil acts as a heat source during winter while a heat sink during summer. Global warming and urban heat island have increased the soil temperatures with an average rate $0.3\~0.5^{\circ}C/10-year$ as in the air temperature during last 30 years $(1973\~2002)$. However, the warming rate is maximized during spring contrary to the winter in the air temperature. The temporal variation of soil temperatures is strongly affected by that of soil moisture through an modification of the heat capacity and heat convection. In general, the increased soil moisture clearly decreased the temporal variations and increased the deep layer soil temperatures during cold season.