Significance of Microsatellite Instability in Early Gastric Cancer Treated by Endoscopic Submucosal Dissection / 대한소화기학회지

BACKGROUND/AIMS: Microsatellite instability (MSI) is defined as a change of any length due to either insertion or deletion of repeating units, in a microsatellite within a tumor when compared to normal tissue. MSI is closely related with genetic instability, particularly in hereditary nonpolyposis colorectal cancer. MSI is found in 10-50% of all gastric cancers, suggesting that MSI may play an important role in carcinogenesis. The aim of this study was to investigate the relationship between microsatellite instability and clinicopathologic features in early gastric cancers (EGCs) treated by endoscopic submucosal dissection (ESD). METHODS: We analyzed clinicopathological features of 95 specimens of EGCs including MSI, histologic type, mucin phenotype, p53, VEGF, location of cancer, depth of invasion, incidence of synchronous and metachronous cancer, age, and gender derived from 94 patients, treated by ESD during recent 19 months were analyzed in this study. RESULTS: According to microsatellite stability, MSI was observed in 13 (13.7%) cases of 95 specimens. The incidence of MSI was increased in patients with cancer at lower part of stomach and female gender. There was no significant relation between MSI and clinicopathologic features including histologic type, mucin phenotype, p53, VEGF, and depth of invasion. CONCLUSIONS: Our results demonstrate that there is no relationship between MSI and clinicopathologic features except tumor location and gender in ECGs treated by ESD. However, further studies are needed to evaluate the significance of MSI in EGCs.

Eradication Rate of First-line and Second-line Therapy for Helicobacter pylori Infection, and Reinfection Rate after Successful Eradication / 대한소화기학회지

BACKGROUND/AIMS: The increasing trend of antibiotic resistance emphasizes the need for the assessment of eradication rate of first and second-line therapy for Helicobacter pylori (H. pylori) infection. The reinfection rate depends on the geographical, national, or socioeconomic status of the patients. The aim of this study was to evaluate the recent 5-year changes of eradication rates and the reinfection rates after the successful eradication of Helicobacter pylori infection for 3-years follow-up in Bucheon, Korea. METHODS: From February 2001 to August 2006, 3,267 patients with H. pylori-positive peptic ulcer disease received the first-line therapy for 7 days. The 317 patients who failed to the first-line therapy received the second-line therapy for 7 days. The 167 patients with 3-years follow-up after the successful eradication were included. (13)C-urea breath tests or rapid urease tests and histologies were assessed to determine the H. pylori status after the eradication. RESULTS: The eradication rate of first-line therapy was 83.7% in 2001, 83.4% in 2002, 83.7% in 2003, 85.9% in 2004, 87.2% in 2005, and 81.8% in 2006 by per protocol analysis (PP), respectively. The eradication rate of second-line therapy was 80.0% in 2002, 86.8% in 2003, 89.7% in 2004, 98.0% in 2005, and 78.8% in 2006 by PP. The cumulative reinfection rate was 6.0%. The annual reinfection rate was 2.0%. The recurrence rate of peptic ulcer was 17.2% in the patients without reinfection and 50% with reinfection. CONCLUSIONS: The eradication rate for H. pylori have not changed in the recent 5-years. The annual reinfection rate was low. The successful eradication of H. pylori was effective for preventing the recurrence of peptic ulcers.

A Comparative Study for Usefulness of a Variable-Stiffness Colonoscope to a Conventional Colonoscope / 대한소화기내시경학회지

BACKGROUND/AIMS: Loop formation during colonoscopy can adversely effect on completion rates, speed of intubation and patient tolerance of the procedure. The ability to vary endoscope shaft flexibility may help insertion to the cecum. The aim was to compare a variable colonoscope with adjustable shaft stiffness to a conventional colonoscope (CC). METHODS: Consecutive patients attending for day case colonoscopy were randomized for examination with either the conventional colonoscope (Olympus CF200Z) or a variable stiffness (VS) colonoscope (CFQ240AL). The time to the cecum, inserted length of scope at cecum, need for abdominal compression, need for rotation of body position and pain scores of patient were analyzed. RESULTS: Of 158 cases, 69 were performed with the CC, and 89 with VS. There was no difference in intubation time between VS (mean 5.15+/-2.61 min) and CC (6.01+/-3.31 min) in experienced group. However, intubation time was quicker with VS than with CC (VS: 8.48+/-5.59, CC: 11.58+/-4.70, p=0.039) and number of loop formation was less with VS (mean 1.20) than with CC (mean 1.84) (p=0.043) in trainee group. There were no significant differences in inserted length of scope at cecum, need for abdominal compression, pain score or need for patient rotation between VS and CC in two groups. CONCLUSIONS: There was no significant difference in cecal intubation time between two groups in experienced group. However, in trainee group, the intubation time was quicker and the number of loop formation were lower in VS group than CC group.

The Study of Pathologic Difference between Endoscopic Biopsy before EMR and Histology of Specimen after Endoscopic Mucosal Resection (EMR) on Gastric Flat Adenoma or Early Gastric Cancer (EGC) / 대한소화기내시경학회지

BACKGROUND/AIMS: It is not uncommon to show discrepancy between the histology of the endoscopic biopsy and that of the resected specimen obtained from the same lesion by EMR. The aim of this study was to ascertain whether routine endoscopic biopsy specimens are sufficient to qualify the representative enough to reliable indication of EMR. METHODS: We retrospectively reviewed 36 cases that could be compared the histologic results from the resected specimens by EMR to the tissue obtained by endoscopic biopsy. The histologic slides were reviewed by one pathologist. RESULTS: Of the 36 cases, 13 cases of EGC and 23 cases of gastric flat adenomas were included. Among 13 cases of EGC, 2 case (15.4%) revealed discrepancy between the histology of the endoscopic biopsy and that of a resected specimen by EMR. The histology of a resected specimen by EMR revealed moderate differentiated adenocarcinoma, while that of endoscopic biopsy was a well differentiated adenocarcinoma. Gastric flat adenoma revealed 47.8% (11/23) of discrepancy. CONCLUSIONS: The histologic discrepancy between the result of endoscopic biopsy and that of the resected specimen obtained by EMR was about 8% in EGC and 47.8% in gastric flat adenoma.

Factors involved in the Transition from Achalasia to Nutcracker Esophagus or Diffuse Esophageal Spasm after Intrasphincteric Injection of Botulinum Toxin / 대한소화관운동학회지

BACKGROUND/AIMS: To evaluate the factors which are related to the transition from achalasia to diffuse esophageal spasm (DES) or nutcracker esophagus (NE) after botulinum toxin injection to lower esophageal sphincter (LES). METHODS: This study included the 23 patients with achalasia who received an intrasphincteric injection of botulinum toxin. Stational esophageal manometry, 24-hour ambulatory esophageal manometry with pH monitoring, barium esophagogram and endoscopic ultrasonography were performed before and after treatment. We analyzed the parameters from these studies between the cases that transformed to DES or NE within a week and the cases that do not transit. RESULT: Five patients (21.7%) transformed to DES (1) or NE (4) within a week. There were significant differences in contraction amplitude of esophageal body (median, 31 mmHg vs 23 mmHg, p < 0.05) and maximal diameter of esophageal body (median, 2.6 cm vs 4.4 cm, p < 0.05) between these five patients and the remaining patients. There were no significant differences in sex, LES pressure and thickness of muscle layer between two groups. CONCLUSION: Factors involved in transition to NE or DES after botulinum toxin injection to LES of achalasia appears as high amplitude contractions in body of esophagus and less dilation of esophageal body.

Diagnosis of Helicobacter pylori Infection by Pronto Dry Test / 대한소화기내시경학회지

BACKGROUND/AIMS: Pronto Dry test, a new rapid urease test, is consisted of a dry filter paper containing urea and has been reported to have a more rapid reaction time than others. We performed this study to compare the accuracy of Pronto Dry test with the other conventional tests for detection of H. pylori. METHODS: One hundred patients underwent gastroscopy in our hospital for gastrointestinal symptoms. Biopsy specimens were taken for Pronto Dry test, polymerase chain reaction, culture, and histologic examination (Warthin-Starry stain). 13C-urea breath test was also performed. The results of Pronto Dry test were read after 1 hour. RESULTS: The sensitivity, specificity, positive and negative predictive value of Pronto Dry test to diagnose H. pylori infection were 90.0%, 100%, 100%, and 90.9%, respectively. The kappa statistic between H. pylori status and Pronto Dry test was 0.90, demonstrating an acceptable level of reliability. CONCLUSIONS: Pronto Dry test has a high sensitivity and specificity, and can be used as a rapid test to diagnose H. pylori infection.

Diagnosis of Helicobacter pylori Infection by Pronto Dry Test / 대한소화기내시경학회지

BACKGROUND/AIMS: Pronto Dry test, a new rapid urease test, is consisted of a dry filter paper containing urea and has been reported to have a more rapid reaction time than others. We performed this study to compare the accuracy of Pronto Dry test with the other conventional tests for detection of H. pylori. METHODS: One hundred patients underwent gastroscopy in our hospital for gastrointestinal symptoms. Biopsy specimens were taken for Pronto Dry test, polymerase chain reaction, culture, and histologic examination (Warthin-Starry stain). 13C-urea breath test was also performed. The results of Pronto Dry test were read after 1 hour. RESULTS: The sensitivity, specificity, positive and negative predictive value of Pronto Dry test to diagnose H. pylori infection were 90.0%, 100%, 100%, and 90.9%, respectively. The kappa statistic between H. pylori status and Pronto Dry test was 0.90, demonstrating an acceptable level of reliability. CONCLUSIONS: Pronto Dry test has a high sensitivity and specificity, and can be used as a rapid test to diagnose H. pylori infection.