ABSTRACT
BACKGROUND: Pancreatic cysts are being increasingly identified in patients. Mucinous cysts have malignant potential whereas non-mucinous cysts do not. Distinguishing potentially malignant cysts from harmless ones by the characterization of cyst fluid contents remains a difficult problem. This study was undertaken to determine whether cyst fluid mucin glycoprotein analysis could differentiate mucinous from non-mucinous pancreatic cysts. METHODS: Cyst fluid from 28 patients who underwent resection of a pancreatic cyst was used for the study. In each case the type of cyst was histologically identified. One dimensional SDS polyacrylamide gel electrophoresis (1D-SDS PAGE) was performed on cyst fluid samples. For the detection of the separated proteins, we employed a novel dual staining technique. The gel was first stained with periodic acid Schiff (PAS), a mucin histochemical stain followed by a secondary protein staining with Simply Blue Safestain (Invitrogen). RESULTS: Visual scoring (based on the presence of mucins) gave a sensitivity of 95%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 88% for prediction of mucinous histology. CONCLUSIONS: One dimensional SDS polyacrylamide gel electrophoresis of pancreatic cyst fluid, followed by mucin (PAS) and protein (Simply Blue Safestain) staining, provides a means of concentrating and visualizing mucins, which allows the accurate differentiation of mucinous from non-mucinous histology in pancreatic cysts.
ABSTRACT
BACKGROUND: Increasing reports suggest that endoscopic removal of benign ampullary and duodenal polyps is safe and frequently definitive; however, most reported polyps have been small in size (<3 cm). We have developed experience with endoscopic removal of increasingly large and complex polyps. PATIENTS: Fifty-one cases of endoscopic removal were attempted and grouped according to size: group A (n = 22) polyps 1 to 3 cm and group B (n = 29) polyps 3 cm or larger, including 7 cases larger than 5 cm. When the ampulla was involved, biductal sphincterotomy and prophylactic pancreatic duct stent placement was performed first, followed by saline solution-assisted piecemeal polypectomy, argon plasma coagulation, selective endoclip placement, and recovery of all polyp fragments. INTERVENTIONS: Endoscopic removal of duodenal and ampullary adenomas. RESULTS: The outcomes of small and large adenoma removal include mean number of endoscopic retrograde cholangiopancreatographies required for complete removal (2.09 vs 2.56, P = .392), number of complications (4.5% vs 13.9%, P = .375), discovery of unsuspected cancer (0% vs 10.3%, P = .242), and final definitive resolution (100% vs 86.2%, P = .124). Complete removal was achieved in 92.2% of all patients. LIMITATIONS: This was a single center retrospective study. CONCLUSIONS: Large (>/=3 cm) ampullary and duodenal polyps comprised 56.9% of our endoscopically treated cases and present special challenges to definitive endoscopic removal. Successful removal of even very large sessile lesions is possible with minimal increase in risk.