• Journal of the Korean Data and Information Science Society
• /
• v.26 no.6
• /
• pp.1317-1325
• /
• 2015

There are two types of clinical research to figure out risk factor for disease using collected data. One is prospective study to approach the subjects from the present time and the other is retrospective study to find the risk factor using the subject's information in the past. Both approached and study design are different but the purpose of the two studies is to identify a significant difference between two groups and to find out what the variables to influence groups. Especially when comparing the two groups in clinical research, we have to look at the difference between the impact clinical variables by group while controlling the influence of the baseline characteristics variables such as age and sex. However, in the retrospective study, the difference of baseline characteristic variables can occur more frequently because the past records did not randomly assign subjects into two groups. In clinical data analysis use covariates to solve this problem. Typically, the analysis method using the analysis of covariance of variance, adjusted model, and propensity score matching method. This study is introduce the way of equality adjustment between groups data analysis using covariates in retrospective clinical studies and apply it to the recurrence of gastric cancer data.

• Journal of Gastric Cancer
• /
• v.9 no.1
• /
• pp.1-5
• /
• 2009

In the past, conservative bypass surgery was usually performed for palliation of malignant obstruction of the gastrointestinal tract. However, endoscopic stenting was developed recently, and technical advances and clinical experience have made it possible to establish stent implantation as one of the main treatment options. There are several advantages in stent implantation over bypass surgery, such as high feasibility and technical success rate, non-invasiveness, rapid symptomatic response, short hospitalization, and cost-effect benefits. Complications, such as stent ingrowth, stent injury by bile or acid, and migration, may occur and early re-insertion is frequently needed. Recently, diverse novel stents which are powered to predict stent migration or ingrowth have been developed and are being used in the clinical setting. In general, stent implantation is known to be beneficial in patients who are expected to survive <6 months, and surgical bypass may be more effective in patients who can survive >6 months. In this review, we have compared the technical feasibility, clinical outcomes, complications, and cost-benefit between stent implantation and bypass surgery, and determined the optimal treatment strategy in malignant upper gastrointestinal obstruction.

• Journal of Digestive Cancer Research
• /
• v.3 no.1
• /
• pp.35-38
• /
• 2015

62-year-old patient who had past history of endoscopic submucosal dissection for early gastric cancer at September 2008, underwent endoscopic submucosal dissection of esophagus for early esophageal cancer at mid esophagus during health screening service. Because there was a high risk of lymph node metastasis at biopsy results, concurrent chemoradiotherapy was added to endoscopic submucosal dissection. There was a metachronous cancer at mid-esophagus at March 2013. He underwent endoscopic mucosal resection and photodynamic therapy. Concurrentchemoradiotherapy after endoscopic submucosal dissection is an effective treatment method.

• Journal of Gastric Cancer
• /
• v.7 no.4
• /
• pp.219-227
• /
• 2007

Purpose: Many reconstruction procedures have been developed in order to resolve patient complaints after a total gastrectomy. However, until now, there has been no general agreement with regard to the ideal reconstruction to perform after a total gastrectomy. Moreover, there have been few reports of the long-term effects of different reconstruction procedures. In this study, we compared the long-term nutritional status and quality of life for patients that received either a Roux-en-Y esophagojejunostomy (R-Y), jejunal interposition (JI), jejunal pouch interposition (JPI), or double tract reconstruction (DT), to determine the optimum reconstruction procedure after a total gastrectomy. Materials and Methods: The study consisted of 41 patients younger than 80 years who had undergone a total gastrectomy with curative resection and who had no evidence of recurrence at our hospital between August 2000 and January 2004. The patients were classified into the following four groups, according to the type of reconstruction; simple Roux-en-Y (R-Y group, n=15), jejunal interposition (JI; group, n=8), j Jejunal pouch interposition (JPI group, n=8), double tract interposition (DT group, n=10). The nutritional status was assessed by measuring body weight, serum albumin level, serum hemoglobin level, and the level of serum total protein, and the PNI (Prognostic nutritional index). Quality of life was assessed by GSRS. In addition, endoscopy was performed to confirm the presence of reflux esophagitis. Results: The laboratory findings showed no significant differences between the four groups except for a lower total protein and album level in the DT group after 3 years postoperatively (P=0.006, P=0.033). The percentage of body weight at 1 year, and 3 years postoperatively in the JI group (P=0.013, P=0.011) were significantly less than other groups (P=0.011, P=0.000). The frequency of postoperative symptoms and reflux esophagitis and eating capacity showed no significant differences between the four groups. The GSRS score in the JIP group was significantly better than for the other groups at 1 year, and 3 years postoperatively (P=0.028, P=0.003). Conclusion: We believe that the jejunal pouch interposition is the most useful of the four procedures for improving postoperative quality of life.

• Journal of Gastric Cancer
• /
• v.5 no.1
• /
• pp.40-46
• /
• 2005

Purpose: Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms of the gastrointestinal tract. GISTs are positive for the expression of c-Kit protein at immunohistochemistry, and their clinical presentations vary. This retrospective study was performed to evaluate the clincopathologic characteristics of GISTs and to define the prognostic factors. Materials and Methods: 40 patients who underwent a complete resection of a GIST during the period $1996\~2003$ at the Department of Surgery, Korea University College of Medicine, were studied. We divided them into low- and high-risk. groups by using tumor size and mitotic count: 23 cases were low risk, and 17 were high risk. Clinicopathologic features, immunohistochemical findings, and prognoses were compared between the low- and the high-risk groups. Results: The mean age of the 40 patients was $61.3\pm11.1$years, and the male-to-female ratio was 1：1.1. There was no significant difference in age and sex between the groups. A comparative analysis revealed tumor size, mitotic count, clinical symptoms, preoperative pathologic diagnosis, ulceration, and necrosis to be variables that had statistically significant differences between the high- and the low-risk groups. In the univariate analysis, tumor size, mitotic count, ulceration, necrosis, and abnormal endoscopic ultrasound findings were associated with disease-free survival, but in the multivariate analysis, mitotic activity was the only independent factor associated with disease-free survival. 8 patients had recurrences during the follow-up period, and four of them were treated with STI-571 (imatinib mesylate, $Gleevec^{(R)}$). The treated patients have survived until now; however, two of non-treated patients died from disease progression. Conclusion: Based on this study, tumor size, ulceration, and necrosis are significant factors affecting survival, and mitotic activity may be a useful prognostic marker. STI-571 may be used in an adjuvant setting because the drug has shown anticancer activity in patients with recurrence or metastasis.

• Tuberculosis and Respiratory Diseases
• /
• v.48 no.6
• /
• pp.909-921
• /
• 2000

Background : Defects in apoptotic signaling pathways play important role in tumor initiation, progression, metastasis and resistance to treatment. Several proteins which may promote tumorigenesis by inhibiting apoptosis were identified. The survivin protein is the member of inhibitor of apoptosis protein(IAPs) family which inhibits apoptosis. Unlike other IAPs, it is expressed in during the fetal period but not in adult differentiated tissues. Many reports have stated that survivin is selectively expressed in many cancer cell lines and cancer tissues. We performed immunohistochemical analysis for survivin expression in non-mall cell lung cancer to get evaluate its clinical implication. Methods : Twenty nine surgically resected lung cancers were examined. Immunohistochemical staining were performed by immuno-peroxidase technique using avidin-biotinylated horseradish pemxidase complex in the formalin-fixed, paraffin-embedded tissue $4{\mu}m$ section. Anti-survivin polyclonal antibody was used for primary antibody and anti-p53 monoclonal antibody was also used to analyze the correlation between survivin and p53 expression. The survivin expression scores were determined by as the sum of the stained area and intensity. Results : Immunohistochemical analysis showed cancer specific expression of survivin in 20 of 29 cases (69.0%). Western blot analysis also showed the selective survivin expression in tumor tissue. There was no correlation between survivin expression and clinicopathological parameters and prognosis. We analyzed the ∞π'elation between survivin expression and p53 expression, but found none. Conclusion: We confirmed the tumor specific expression of survival in non-small cell lung canær. But this expression was not correlated with clinical parameters as well as histology, tumor stage, recurrence, and survival rate. Also it was not statistically correlated with the expression of p53.

• Tuberculosis and Respiratory Diseases
• /
• v.50 no.6
• /
• pp.676-685
• /
• 2001

Background : Angiogenesis is an essential component of tumor growth and metastasis, and the vascular endothelial growth factor (VEGF) is one of the most important angiogenic factors. Several solid tumors produce substantial amounts of VEGF, which stimulates proliferation and the migration of endothelial cells, thereby inducing neovasculization by a paracrine mechanism. To evaluate the prognostic roles of angiogenesis and VEGF expression in patients with non-small cell lung cancer, the relationship between VEGF expression in tumor tissues, the clinicopathologic features and the overall survival rate were analysed. Methods : Sixty-nine resected primary non-small cell lung cancer specimens were evaluated. The paraffin-embedded tumor tissues were stained by anti-VEGF polyclonal antibodies using an immunohistochemical method to assess VEGF expression. Results : In Forty-one patients (59%), the VEGF antigen was expressed weakly in their tumor tissue, whereas in twenty-eight patients (41%) the VEGF antigen was expressed strongly. The median survival time of the weak VEGF expression group was 24 months, and that of the strong VEGF expression group was 19 months. The three year-survival rates were 35%, 33%, respectively. The survival difference between both groups was not statistically significant. Conclusion : Although results were not statistically significant, the strong expression group tended to poorer prognosis than the weak expression group.

• Journal of Gastric Cancer
• /
• v.5 no.4 s.20
• /
• pp.246-251
• /
• 2005

Purpose: Benign anastomotic stricture after an esophagojejunostomy using EEA stapler following a radical total gastrectomy is one of the most serious complications. The purpose of this study is to evaluate the incidence risk factors, and treatment associated with benign stricture. Materials and Methods: From March 1998 to February 2001, 436 patients underwent an esophagojejunostomy with Roux-en-Y anastomosis using an EEA stapler followed by an endoscopy. Thirty three of the 436 patients(5.5%) developed an anastomotic stricture; included 24 of the 33 patients had a benign stricture. Nine patients with a malignant stricture were excluded. Results: The median age of the 436 patients was 57 years $(23{\sim}85\;years)$. Two hundred ninety two patients were male, and 144 patients were female. The median time to diagnosing the stricture was 1.5 months $(0.5{\sim}6months)$. There was no statistical significance in any of the risk factors, including the diameter of the stapling device, the status of adjuvant treatment, the status of reflux esophagitis, and a clinical history of diabetes and hypertension. The strictured patients were treated with balloon dilatation, one to three times, with symptom relief. Conclusion: There were no statistically significant risk factors. However, further study of the vascularity of anastomoses and benign strictures needs to be considered. In the anastomotic strictured patients endoscopic balloon dilatation appeared to be the first line of treatment.

• Journal of Chest Surgery
• /
• v.43 no.3
• /
• pp.280-284
• /
• 2010

Background: The postoperative management following lung transplantation has dramatically improved in the recent decade. However, some complications still remain as troublesome problems. We retrospectively reviewed the gastrointestinal complications and their management after lung transplantation. Material and Method: We performed a retrospective review of the medical records of 25 cases in 23 patients who underwent lung and heart-lung transplantations from July 1996 to March 2009. The definition of gastrointestinal complication was the gastrointestinal tract-related disease that occurred after lung transplantation. There were eight postoperative deaths (within postoperative 30 days) that were excluded from the analysis. Result: Twenty three gastrointestinal complications occurred in 11 (64.7%) of the 17 cases. The median follow-up period was 6.9 months (range: 2 months to 111 months), and chronic gastritis (23.5%, 4 of 17 cases) was the most common complication. Severe, prolonged (more than 2 weeks) diarrhea occurred in 3 cases. Three patients had gastric ulcer with one case requiring gastric primary closure for gastric ulcer perforation. This patient had gastric bleeding due to recurrent gastric ulcer 2 months after laparotomy. Cytomegalovirus gastritis and esophagitis occurred in 2 cases and 1 case, respectively, and esophageal ulcer occurred in 2 cases. There were esophageal strictures in 2 patients who underwent esophageal stent insertion. Other complications were one case each of ileus, early gastric cancer requiring endoscopic mucosal resection, gall bladder stone accompanied with jaundice, and pseudomembranous colitis. Conclusion: The incidence of gastrointestinal complication is relatively high in patients after they undergo lung transplantation. Since gastrointestinal complications can induce malnutrition, which might be related to considerable morbidity and mortality, close follow-up is necessary for the early detection and proper management of gastrointestinal complications.

• Journal of Gastric Cancer
• /
• v.8 no.4
• /
• pp.225-231
• /
• 2008

Purpose: Laparoscopic gastric resection (LGR) is increasingly being used instead of open gastric resection (OGR) as the standard surgical treatment for gastric submucosal tumors. Yet there are few reports on which technique shows better postoperative outcomes. This study was performed to compare these two treatment modalities for gastric submucosal tumors by evaluating the postoperative outcomes. We also provide an analysis of the learning curve for LGR. Materials and Methods: Between 2003.4 and 2008.8, 103 patients with a gastric submucosal tumor underwent either LGR (N=78) or OGR (n=25). A retrospective review was performed on a prospectively obtained database of 103 patients. We reviewed the data with regard to the operative time, the blood loss during the operation, the time to the first soft diet, the postoperative hospital stay, the tumor size and the tumor location. Results: The clinicopatholgic and tumor characteristics of the patients were similar for both groups. There was no open conversion in the LGR group. The mean operation time and the bleeding loss were not different between the LGR group and the OWR group. The time to first soft diet (3.27 vs. 6.16 days, P<0.001) and the length of the postoperative hospital stay (7.37 vs. 8.88 days, P=0.002) were shorter in the LGR group compared to the OGR group. The tumor size was bigger in the OGR group than that in the LGR group (6.44 vs. 3.65 cm, P<0.001). When performing laparoscopic gastric resection of gastric SMT, the surgeon was able to decrease the operation time and bleeding loss with gaining more experience. We separated the total cases into 3 periods to compare the operation time, the bleeding losses and the complications. The third period showed the shortest operation time, the least bleeding loss and the fewest complications. Conclusion: LGR for treating a gastric submucosal tumor was superior to OGR in terms of the postoperative outcomes. An operator needs some experience to perform a complete laparoscopic gastric resection. Laparoscopic resection could be considered the first-line treatment for gastric submucosal tumors.