Tae Jun Byun

The Miss Rate for Colorectal Adenoma Determined by Quality-Adjusted, Back-to-Back Colonoscopies.

Background/Aims Colonoscopy is considered to be the gold standard for detecting adenomatous polyps. Polyps are missed during colonoscopic examination at a rate that varies from 6% to 27%. The adenoma miss rate affects colonoscopic surveillance intervals and procedural quality. We aimed to assess the adenoma miss rate and the variables affecting the rate using same-day, quality-adjusted, back-to-back colonoscopies. Methods This prospective study was performed at a single institution and included 149 patients. Two consecutive same-day colonoscopies were performed by two experienced endoscopists. The adenoma miss rates and variables affecting the missed adenomas, including polyp characteristics and procedure times, were evaluated. Results The miss rates of polyps, adenomas, and advanced adenomas were 16.8%, 17%, and 5.4%, respectively. The smaller polyps and increased number of polyps detected during the first colonoscopy were more likely to be missed. A longer insertion time during the colonoscopy was correlated with an increased adenoma detection rate. Conclusions There was a significant miss rate in the detection of colonic adenomas even in quality-adjusted, back-to-back colonoscopies. The adenoma miss rate can be reduced with a sufficient observation time during colonoscopic insertion. The development of specific technological methods to reduce the adenoma miss rate is necessary.

Pseudoinvasion in an Adenomatous Polyp of the Colon Mimicking Invasive Colon Cancer

Pseudoinvasion or pseudocarcinomatous invasion in an adenomatous polyp of the colon can be unfamiliar to an endoscopist. Pseudoinvasion in an adenomatous polyp represents prolapse of the adenomatous epithelium into its stalk. In most cases its morphology does not differ from of general adenomatous polyps, but in some cases it can morphologically mimic a malignant polyp with submucosal invasion due to mass-like lesioning of its stalk. This makes it difficult for endoscopists to differentiate pseudoinvasion in an adenoma from an invasive carcinoma by conventional endoscopy; instead, endoscopic ultrasonography can provide useful information for differentiating these conditions. We report on an 82-year-old man who presented with a large pedunculated polyp with a thick stalk in the sigmoid colon, which mimicked a submucosal invasive carcinoma. The patient was diagnosed with pseudoinvasion in an adenomatous polyp after segmental resection of the sigmoid colon.

Comparison of the Effectiveness of Interventional Endoscopy in Bleeding Peptic Ulcer Disease according to the Timing of Endoscopy

Background/Aims The optimal timing for interventional endoscopy in bleeding peptic ulcer disease is controversial. This study compared the outcomes between early endoscopy and delayed endoscopy in patients with bleeding peptic ulcer disease. Methods We conducted a prospective analysis of data from 90 patients with bleeding peptic ulcer disease who visited the emergency room between May 2006 and September 2007. Patients were categorized into two groups: the early-endoscopy group (admitted during the daytime or at night with prompt endoscopic management) and the delayed-endoscopy group (admitted at night or during weekends, with endoscopic management delayed until the next day). We compared the clinical outcomes of endoscopy between the two groups. Results There were 49 patients in the early-endoscopy group and 41 patients in the delayed-endoscopy group. Patient demographics, clinical characteristics, bleeding control modality, and Rockall score did not differ between the two groups. There were also no significant differences between the early- and delayed-endoscopy groups in the re-bleeding rate (3/49 vs 5/41, p=0.313), the duration of hospital stay (10.7 vs 9.3 days, p=0.437), and the total amount of blood transfused (3.4 vs 2.7 units, p=0.240). Conclusions The effectiveness of interventional endoscopy for patients with bleeding peptic ulcer disease is not significantly affected by the timing of endoscopy.