BACKGROUND/AIMS: Colorectal cancer (CRC) with microsatellite instability (MSI) has a better prognosis than CRC with microsatellite stable (MSS). Recent studies have reported biological differences according to tumor location in CRC. In this study, we investigated the clinical significance of MSI in patients with right-sided CRC. METHODS: The medical records of 1,009 CRC patients diagnosed at our institute between October 2004 and December 2016 with MSI test results were retrospectively reviewed. The long-term outcomes of CRC patients with MSI were assessed with respect to tumor location using Kaplan-Meier curves and Cox regression models. RESULTS: The median follow-up duration for all 1,009 study subjects was 25 months (interquartile range, 15–38). One hundred twenty-four of the study subjects had MSI (12.3%) and 250 had right-sided CRC (24.8%). The patients with MSI and right-sided CRC had better disease-free survival (DFS) than those with MSS as determined by the log-rank test (p=0.013), and this result was significant in females (p=0.035) but not in males with right-sided CRC. Multivariate Cox regression analysis showed MSS significantly predicted poor DFS in patients with right-sided CRC (hazard ratio 3.97, 95% CI 1.30–12.15, p=0.016) and in female patients (hazard ratio 4.69, 95% CI 1.03–21.36, p=0.045). CONCLUSIONS: The study shows MSI is a useful predictor of DFS in patients with right-sided CRC, especially in female patients.
Colorectal Neoplasms ; Disease-Free Survival ; Female ; Follow-Up Studies ; Gender Identity ; Humans ; Male ; Medical Records ; Microsatellite Instability ; Microsatellite Repeats ; Prognosis ; Retrospective Studies

BACKGROUND/AIMS: The higher prevalence of gastroesophageal reflux disease has preceded the increase of Barrett's esophagus and esophageal adenocarcinoma in Western countries. An increase of Barrett's esophagus and esophageal adenocarcinoma can also be predicted due to the increase of gastroesophageal reflux disease in Asia. Therefore, the ability of endoscopists to detect Barrett's esophagus can be important in the future. The aim of this study was to examine whether a short education program could improve the ability of gastrointestinal endoscopists and nurses to detect Barrett's esophagus. MATERIALS AND METHODS: Endoscopists and nurses of Gastrointestinal Endoscopic Center in Kosin Uinversity Gospel Hospital were enrolled in this study. Endoscopic images of biopsy proven Barrett's esophagus and normal gastroesophageal junction were obtained with conventional endoscopy. Thirty-seven still images of conventional endoscopy were used for slide test before and after 15 minutes education on Barrett's esophagus. RESULTS: Diagnostic ability of the doctor group after education did not changed (pre-education 79.6% vs. post-education 79.3%, P=0.906). Nurse group showed improved diagnostic ability for Barrett's esophagus after education (pre-education 68.7% vs. post-education 75.5%, P=0.008). After a short education program, inter-observer agreement of endoscopic diagnosis of Barrett's esophagus was improved in both doctor and nurse groups (doctor inter-observer correlation coefficient [ICC], 0.684→0.879; nurse ICC, 0.524→0.862). CONCLUSIONS: Even a short education program can improve the diagnostic ability, especially inter-observer agreement of endoscopic diagnosis for Barrett's esophagus. Further studies are needed to establish a role of education to improve diagnostic ability of Barrett's esophagus.
Adenocarcinoma ; Asia ; Barrett Esophagus* ; Biopsy ; Diagnosis ; Education* ; Endoscopy ; Esophagogastric Junction ; Gastroesophageal Reflux ; Prevalence

BACKGROUND/AIMS: Small subepithelial tumors (SETs) are often found incidentally during esophagoduodenoscopy, and EUS is a useful tool for assessing SETs. This study aimed to evaluate the natural history of SETs and to clarify the predictive factors of growth using EUS. MATERIALS AND METHODS: We retrospectively investigated SETs less than 30 mm and identified the EUS features. A significant increase in SET size was defined as a lengthening of more than 25% of the longest diameter in the last follow-up EUS features compared with the initial study. RESULTS: A total of 99 patients with 105 upper gastrointestinal SETs were enrolled. The mean follow-up period for SETs was 22.8 months. Among the 105 SETs, 12 (11.4%) were significantly larger at follow-up. Univariate analysis revealed that the presence of hypoechoic areas was associated with significant SET growth (P=0.021). In multivariate analysis, the presence of hypoechoic areas (OR, 8.96; 95% CI, 1.89~42.54) and anechoic areas (OR, 7.85; 95% CI, 1.09~56.37) were related with significant growth of SETs. Six of the 12 SETs showing significant growth were removed, and identified as gastrointestinal stromal tumors. CONCLUSIONS: Majority of small SETs showed no significant increase during follow-up. Presence of hypoechoic areas and anechoic areas were associated with SET growth. Therefore, small SETs with hypoechoic area or anechoic area may be considered for regular follow-up in the clinical field.
Endosonography* ; Follow-Up Studies ; Gastrointestinal Stromal Tumors ; Humans ; Multivariate Analysis ; Natural History* ; Retrospective Studies

BACKGROUND/AIMS: Helicobacter pylori is a distinctive pathogen that lives in the gastric mucosa and is a well known risk factor of gastric adenocarcinoma. Iron deficiency aggravates the development of H. pylori-induced premalignant and malignant lesions in a cagA-dependent manner, enhancing H. pylori virulence. The aim of this study was to identify the relationship between iron deficiency and H. pylori eradication rates. MATERIALS AND METHODS: Participants who received 7 days of first-line triple therapy with serum iron level measured in parallel were retrospectively investigated between 2005 and 2014. H. pylori eradication was confirmed by the rapid urease test or 13C-urea breath test at least 4 weeks after completion of triple therapy. Iron deficiency was defined as either a serum iron level less than 50 µg/dL or a serum ferritin level less than 12 ng/mL. RESULTS: A total of 194 patients received 7 days of first-line triple therapy along with parallel serum iron level measurements over the 10-year period. The mean average age was 53.3 years (range, 21~86 years), and 135 patients (69.6%) were male. The overall H. pylori eradication rate was 83.5%. Proportions of eradication success with ferritin level less than 12 ng/mL and iron less than 50 µg/dL were 90.5% and 88.6%, respectively. However, there was no statistical difference in eradication rates according to iron deficiency. CONCLUSIONS: Iron deficiency might not be related with H. pylori eradication rates in this study. Further large-scale studies are needed to confirm this result.
Adenocarcinoma ; Breath Tests ; Disease Eradication ; Ferritins ; Gastric Mucosa ; Helicobacter pylori* ; Helicobacter* ; Humans ; Iron* ; Male ; Retrospective Studies ; Risk Factors ; Urease ; Virulence

Solitary extramedullary plasmacytoma (EMP) is a plasma cell neoplasm without bone marrow involvement. EMPs are rare in the gastrointestinal (GI) tract. We report two cases of primary EMP, one in the transverse colon and the other in the stomach. In the first case, a mass on the transverse colon was found on colonoscopy. The patient underwent left hemicolectomy and has been followed-up for 3 years without recurrence postoperatively. The latter case had several masses in the stomach. The patient underwent bypass surgery and has received supportive care for 1 month. Histopathologic specimens of both the cases showed a monoclonal lambda chain EMP. Subsequent investigations included a bone marrow biopsy, serum IgA, IgG, IgM and serum protein electrophoresis, and the results were negative for multiple myeloma in both the cases. Solitary EMP in the GI tract can be mistaken for colon cancer or stomach cancer on endoscopy; therefore, a sufficient number of biopsy specimens can help diagnose solitary EMPs. Surgical resection alone or with radiation therapy in cases with positive surgical margin is currently the only treatment for solitary EMP in the GI tract. Further study is necessary to determine disease prognosis and to investigate other treatment methods.
Colonic Neoplasms/*diagnosis/pathology/therapy ; Endoscopy, Gastrointestinal ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Plasmacytoma/*diagnosis/pathology/therapy ; Positron-Emission Tomography ; Stomach Neoplasms/*diagnosis/pathology/therapy ; Tomography, X-Ray Computed

OBJECTIVES: Prenatal testosterone is known to influence both cerebral laterality and 2nd to 4th digit ratio (2D : 4D). Epigenetic changes are thought to play some role in it. We studied sex-related differences between 2D : 4D and cerebral laterality in patients with schizophrenia and controls to examine the effects of prenatal testosterone in the development of schizophrenia. METHODS: Forty one men (18 schizophrenic patients and 23 controls) and 40 women (17 schizophrenic patients and 23 controls) were recruited from one psychiatric hospital in Korea. The 2D : 4D and electroencephalographic (EEG) coherence in 19 channels (66 pairs of interhemispheric coherence and 54 pairs of intrahemispheric coherence) were measured. The sex-related statistical analyses between 2D : 4D and EEG coherence in controls and patients with schizophrenia were performed using multiple regression. RESULTS: In male patients, the relationship between 2D : 4D and right intrahemispheric EEG coherence showed mainly positive correlation in delta and theta frequency bands, while it showed negative correlation in male controls. In female patients, the relationship between 2D : 4D and interhemispheric EEG coherence showed stronger positive correlation in alpha and beta frequency bands, while it showed weaker positive correlation in female controls. CONCLUSIONS: Low prenatal testosterone may play certain roles in altered correlation between 2D : 4D and cerebral laterality in schizophrenia and the development of schizophrenia by epigenetic mechanism.
Electroencephalography ; Epigenomics ; Female ; Hospitals, Psychiatric ; Humans ; Korea ; Male ; Schizophrenia* ; Testosterone

PURPOSE: We propose an equation that predicts graft function after kidney transplantation by using donated kidney volume and recipient body surface area (BSA). MATERIALS AND METHODS: Included were 261 cases of living kidney transplantation between 2007 and 2009. Preoperative computed tomography scans were performed and the donated kidney volume was measured by use of a three-dimensional reconstruction program (Ripidia). The estimated glomerular filtration rate (eGFR) was calculated by using the modification of diet in renal disease formula. Donated kidney volume, preoperative renal function, and demographic factors of both donors and recipients were evaluated as predictors. RESULTS: The mean ages of the donors and recipients were 40.8 and 41.6 years, respectively. The mean donated kidney volume and donated kidney volume/recipient BSA ratio were 153.4 mL and 96.9 mL/m2, respectively. Mean preoperative and postoperative 12-month eGFR of recipients were 7.1 and 59.7 mL/min, respectively, and the mean preoperative eGFR of donors was 92.2 mL/min. Donated kidney volume/recipient BSA ratio, donor age, and recipient gender were the significant predictors of eGFR level (p<0.001) and eGFR<45 mL/min at postoperative 12 months (p=0.005, p<0.001, and p=0.006). From the multiple linear regression equation and predicted probability from logistic regression, we could calculate the equation for the ratio of living donor kidney volume to recipient BSA on graft function. CONCLUSIONS: Graft kidney volume/recipient BSA ratio, donor age, and recipient gender were predictors of graft function 12 months after kidney transplantation. Although we are concerned only with the preoperative, this equation model could help physicians to counsel patients concerning their postoperative prognosis and to avoid insufficient volume donations.
Body Surface Area* ; Delayed Graft Function ; Demography ; Diet ; Glomerular Filtration Rate ; Humans ; Kidney Transplantation ; Kidney* ; Linear Models ; Living Donors* ; Logistic Models ; Organ Size ; Prognosis ; Tissue Donors ; Transplantation ; Transplants*

BACKGROUND/AIMS: This study was designed to compare the efficacy and patient tolerance between standard bowel preparation using 4 liters of polyethylene glycol (PEG) solution and 4 liters of PEG preceded by the osmotic laxative, magnesium hydroxide in constipation and non-constipation group. METHODS: 173 outpatient colonoscopy, except for three patients who were not taking magnesium, were divided into constipation and non-constipation group. Then, the patients were randomly assigned to receive 4-liter of PEG solution or 4-liter of PEG plus magnesium hydroxide. The quality of bowel preparation was assessed using Ottawa scale, and satisfaction score was assessed using questionnaires. Solid stool, cecal intubation time, compliance, and side effects were assessed. RESULTS: Non-constipation group showed no significant differences between two groups. In constipation group, 4-liter PEG solution plus magnesium hydroxide induced the more effective colonic preparation (Ottawa scale 2.47+/-0.99 vs. 5.92+/-2.39, p<0.05), and less solid stool (0.67+/-0.72 vs. 1.38+/-0.65, p<0.05) compared with 4-liter PEG solution. CONCLUSIONS: Bowel preparation with magnesium hydroxide and 4 liters of PEG solution might reduce solid stool in constipation group, but could not improve preparation quality.
Administration, Oral ; Adult ; Aged ; *Colonoscopy ; Female ; Gastric Lavage/*methods ; Humans ; Magnesium Hydroxide/*administration &dosage ; Male ; Middle Aged ; Polyethylene Glycols/*administration &dosage ; Questionnaires

BACKGROUND/AIMS: Polyethylene glycol (PEG) solution is the most widely used bowel preparation agent for colonoscopy because of its safety and efficacy in colon cleansing. It has been hypothesized that the timing of colon preparation may influence the quality of colon cleansing, and therefore affect the diagnostic yield of colonoscopy. The aim of this study was to determine the optimal interval of time between complete ingestion of PEG and performing colonoscopy. METHODS: We prospectively enrolled 1,355 patients who had undergone a PEG-based bowel preparation on the day of colonoscopy in 11 tertiary hospitals in Korea between March 2008 and February 2009. All colonoscopies were performed in the afternoon. The start time of PEG ingestion, completion time of PEG ingestion, dose of PEG ingested, start time of colonoscopy, and the quality of bowel cleansing were recorded. RESULTS: There was no difference of cleansing quality of bowel preparation between three groups of less than 7 hours of elapsed time (2< or = and <3 hours, 3< or = and <5 hours, 5< or = and <7 hours). However, group of more than 7 hours of elapsed time presented poor cleansing quality than others (P<0.01). CONCLUSIONS: If>7 hours elapses after ingestion of PEG, the quality of bowel preparation is poor. Therefore, depending on the time colonoscopy is scheduled, the start time of PEG ingestion may need to be adjusted.
Colon ; Colonoscopy ; Eating ; Humans ; Korea ; Polyethylene ; Polyethylene Glycols ; Prospective Studies ; Tertiary Care Centers

BACKGROUND/AIMS: Polyethylene glycol (PEG) solution is the most widely used bowel preparation agent for colonoscopy because of its safety and efficacy in colon cleansing. It has been hypothesized that the timing of colon preparation may influence the quality of colon cleansing, and therefore affect the diagnostic yield of colonoscopy. The aim of this study was to determine the optimal interval of time between complete ingestion of PEG and performing colonoscopy. METHODS: We prospectively enrolled 1,355 patients who had undergone a PEG-based bowel preparation on the day of colonoscopy in 11 tertiary hospitals in Korea between March 2008 and February 2009. All colonoscopies were performed in the afternoon. The start time of PEG ingestion, completion time of PEG ingestion, dose of PEG ingested, start time of colonoscopy, and the quality of bowel cleansing were recorded. RESULTS: There was no difference of cleansing quality of bowel preparation between three groups of less than 7 hours of elapsed time (2< or = and <3 hours, 3< or = and <5 hours, 5< or = and <7 hours). However, group of more than 7 hours of elapsed time presented poor cleansing quality than others (P<0.01). CONCLUSIONS: If>7 hours elapses after ingestion of PEG, the quality of bowel preparation is poor. Therefore, depending on the time colonoscopy is scheduled, the start time of PEG ingestion may need to be adjusted.
Colon ; Colonoscopy ; Eating ; Humans ; Korea ; Polyethylene ; Polyethylene Glycols ; Prospective Studies ; Tertiary Care Centers