Colorectal

Background and Aims
There are limited data on the use of volumetric laser endomicroscopy (VLE) for imaging colon polyps. Our aim was to identify VLE features of colon polyps. Methods
A total of 45 patients were included; 43 underwent endoscopic mucosal resection of colorectal polyps 2 cm or greater. These polyps were then scanned with VLE immediately after resection. Two patients who underwent partial colonic resection served as controls. Results
Forty-three polyps were included with review of matching histology: 3 intramucosal cancer (IMCA), 5 tubular adenoma (TAs)/tubulovillous adenoma (TVA) with high-grade dysplasia (HGD), 9 TVA with only low-grade dysplasia (LGD), 5 serrated adenoma, and 21 TA with LGD. All TAs and TVAs were hyper-reflective compared with normal tissue. Effacement occurred in 82.4% (14/17) of the colonic polyps with advanced pathology (TVA with HGD/IMCA) compared with 11.6% (3/26) with non-advanced pathology (TA with LGD and serrated adenoma) (P Conclusions
In this ex vivo clinicopathologic study, we show that there are distinct VLE features of colon polyps that may help identify polyps or features of a higher-grade lesion. This may have implications for possible in vivo application to aid in dysplasia or polyp detection.

Background and Aims
Although colonic perforation is a dreadful adverse event associated with stent placement, data on this topic are sparse. We aimed to investigate the clinical outcomes of colonic perforation and factors related to its occurrence in patients who received self-expandable metal stents (SEMSs) for malignant colorectal obstruction. Methods
We retrospectively reviewed the data of 474 patients with malignant colorectal obstruction who received endoscopic SEMS insertion from April 2004 to May 2011 in Severance Hospital and Gangnam Severance Hospital. Early perforation, defined as perforation occurring within 2 weeks, was assessed in bridge-to-surgery (n = 164) and palliative stent placement patient groups (n = 310). Delayed perforation was analyzed using data from the palliative stent placement group alone. Results
The technical and clinical success rates were 90.5% and 81.0%, respectively. Early and delayed perforations occurred in 2.7% (13/474) and 2.7% (8/301) of patients, respectively. Among 21 patients with perforation, 14 (66.7%) received emergency surgery and 5 (23.8%) died within 30 days after perforation. Regarding the perforation-related factors, age ≥70 years (odds ratio, 3.276; 95% confidence interval [CI], 1.041-10.309) and sigmoid colonic location (odds ratio, 7.706; 95% CI, 1.681-35.317) were independently associated with occurrence of early perforation. Stent location in the flexure (hazard ratio, 17.573; 95% CI, 2.004-154.093) and absence of peritoneal carcinomatosis (hazard ratio, 6.139; 95% CI, 1.150-32.776) were significantly associated with delayed perforation. Conclusions
The perforation-related 30-day mortality rate was 23.8%. Older age and sigmoid colonic location were significantly associated with occurrence of early perforation, whereas flexure location and absence of peritoneal carcinomatosis were related to delayed perforation.