Mariano Gonzalez-Haba Ruiz

Complete Endoscopic Mucosal Resection Is Effective and Durable Treatment for Barrett's-Associated Neoplasia

BACKGROUND & AIMS Barretts esophagus (BE) with high-grade dysplasia (HGD) or intramucosal carcinoma (IMC) is treated by complete eradication of areas of BE by endoscopic mucosal resection (EMR). By using this approach, histologic analysis also can be performed. We investigated the effectiveness, safety, and durability of this approach, as well as its use in diagnosis after a single referral. METHODS We collected data from 107 patients who were referred to the Center for Endoscopic Research and Therapeutics at the University of Chicago for BE (mean length, 3.6 cm) with suspected HGD or IMC, from August 2003 through December 2012. All patients underwent EMR and were followed up through January 2014 (mean follow-up time, 40.6 mo). The primary outcome was treatment efficacy (complete eradication of BE and associated neoplasia); secondary outcomes included safety, durability, and accuracy of diagnosis. RESULTS BE was eradicated completely by EMR in 80.4% (86 of 107) of patients based on intention-to-treat analysis, and in 98.8% (79 of 80) of patients based on per-protocol analysis. The diagnosis was changed for 25% of patients after EMR, including 4 cases that initially were diagnosed as HGD by biopsy analysis and subsequently were found to have evidence of submucosal invasion when EMR specimens were assessed. Strictures and symptomatic dysphagia developed in 41.1% and 37.3% of patients, respectively, with an average of 2.3 dilations required. Perforations occurred in 2 patients after EMR and in 1 patient after dilation. HGD and IMC recurred in 1 patient each; both were treated successfully with EMR. Based on pathology analysis of the most recently collected specimens, 71.6% of patients (53 of 74) were in complete remission from intestinal metaplasia and 100% were in complete remission from HGD (74 of 74) or cancer (74 of 74). CONCLUSIONS For patients with BE with HGD or neoplasia, complete EMR is an effective and durable treatment and is a relatively safe technique. Specimens collected by EMR also can be analyzed histologically to aid in diagnosis. The common complication of EMR is esophageal stricture, which can be addressed with endoscopic dilation.

In Vivo Risk Analysis of Pancreatic Cancer Through Optical Characterization of Duodenal Mucosa

Objectives To reduce pancreatic cancer mortality, a paradigm shift in cancer screening is needed. Our group pioneered the use of low-coherence enhanced backscattering (LEBS) spectroscopy to predict the presence of pancreatic cancer by interrogating the duodenal mucosa. A previous ex vivo study (n = 203) demonstrated excellent diagnostic potential: sensitivity, 95%; specificity, 71%; and accuracy, 85%. The objective of the current case-control study was to evaluate this approach in vivo. Methods We developed a novel endoscope-compatible fiber-optic probe to measure LEBS in the periampullary duodenum of 41 patients undergoing upper endoscopy. This approach enables minimally invasive detection of the ultrastructural consequences of pancreatic field carcinogenesis. Results The LEBS parameters and optical properties were significantly altered in patients harboring adenocarcinomas (including early-stage) throughout the pancreas relative to healthy controls. Test performance characteristics were excellent with sensitivity = 78%, specificity = 85%, and accuracy = 81%. Moreover, the LEBS prediction rule was not confounded by patients’ demographics. Conclusion We demonstrate the feasibility of in vivo measurement of histologically normal duodenal mucosa to predict the presence of adenocarcinoma throughout the pancreas. This represents the next step in establishing duodenal LEBS analysis as a prescreening technique that identifies clinically asymptomatic patients who are at elevated risk of PC.

Biliary and Pancreatic Stents: Indications and Placement Techniques

Placement of self-expandable metal stents (SEMS) has now become accepted for the relief of malignant obstruction of the biliary system, either preoperatively or palliatively. The advantage of SEMS over traditional plastic stents is the significant prolongation in patency. Available SEMS are uncovered, partially covered, and completely covered. Covered stents may have prolonged patency as compared to uncovered stents but, more importantly, do not imbed into tissue and thus are removable and have applications for benign disease. Applications of covered SEMS for benign biliary diseases include strictures, leaks closure of perforations, and treatment of postsphincterotomy bleeding. SEMS can be placed percutaneously or endoscopically; the latter is usually done at the time of ERCP, but endoscopic ultrasound guidance can also be used to place SEMS. Applications of SEMS in the pancreas are limited but evolving. This chapter will summarize the indications and techniques for placement of self-expandable metal stents in the biliary tree and for the treatment of pancreatic disease.