Background and study aims: The transpapillary endoscopic insertion of self-expandable metallic stents (SEMSs) has been widely used for the palliation of unresectable malignant biliary obstruction. We attempted the endoscopic removal of malfunctioning SEMSs. The aim of this study was to assess the feasibility and safety of the endoscopic removal of SEMSs by comparing the results between removal of covered and uncovered SEMSs. Patients and methods: 30 patients with a malfunctioning biliary SEMS prospectively underwent an attempt at endoscopic removal of the biliary SEMS over a 2-year period. Removal of the malfunctioning SEMS was done with a therapeutic duodenoscope (ED-450XT5 or TJF-240), using a rat-tooth forceps. Of the 30 SEMS used, 22 were silicone-covered Wallstents, while eight were uncovered SEMSs including five uncovered Wallstents and three Zilver stents. The time for an attempt at each endoscopic removal was limited to 15 minutes in a single endoscopic procedure session. Results: The covered SEMSs were easily removed in 19 out of 22 patients (86.4 %), whereas none of the eight uncovered SEMSs (0 %) could be removed. The only factor predicting successful stent removal was the presence of a stent covering (P = 0.000). There was no morbidity or mortality related to endoscopic removal of malfunctioning stents. Conclusions: In contrast to uncovered biliary SEMSs, in most cases malfunctioning covered biliary SEMSs can be easily and safely removed endoscopically using a rat-tooth forceps.
To develop and validate a risk stratification-based screening model for predicting colorectal advanced neoplasia in Korea. Colorectal advanced neoplasia is the relevant finding of screening colonoscopy. Risk estimation for advanced neoplasia may be helpful to improve compliance and to develop more cost-effective approaches toward screening. We developed Korean Colorectal Screening (KCS) score by optimizing and adjusting Asia-Pacific Colorectal Screening (APCS) score to predict advanced neoplasia in an asymptomatic Korean population who received screening colonoscopies from September 2006 to September 2009. Moreover, we validated the KCS score in another Korean cohort who received screening colonoscopies from October 2009 to February 2011. We also assessed the predictive power and diagnostic performance of both KCS and APCS scores. There were 3561 subjects in the derivation cohort and 1316 subjects in the validation cohort, with a prevalence of advanced neoplasia of 4.7% and 4.3%, respectively. After a multivariate analysis, KCS was developed as 0 to 8 points comprising of age, sex, body mass index, smoking, and family history of CRC. Using KCS scores to stratify the validation cohort, the prevalences of advanced neoplasia in the 3 risk tiers (average, moderate, and high) were 2.0%, 3.7%, and 10.9%, respectively. Moderate-risk and high-risk tiers showed 2.1- and 6.5-fold increased prevalences, respectively, of advanced neoplasia compared with average risk tier. In addition, KCS score showed relatively good discriminative power (ROC=0.681) and higher sensitivity compared with APCS score for the high-risk tier. KCS score may be clinically simple and useful for assessing advanced neoplasia risk in Korea. However, racial disparity should be considered in risk stratification-based screening in each country.
1 January 2009 in Journal of Korean Medical Science