Submucosal Lifting Agent ORISE Gel Remnants Histopathologically Mimic Mucin and Malignancy: A Case Series

Abstract

Introduction There were an estimated 18.1 million new cancer cases in 2018, with colon cancer being the third most common worldwide. Colon cancer development is an accumulation of mutations resulting in normal epithelial cells transforming into adenomas and then adenocarcinomas. In certain scenarios, endoscopic interventions have gained considerable momentum over invasive surgery as an alternative to manage early gastrointestinal lesions. New techniques such as endoscopic mucosal resection (EMR) and endoscopic submucosal dissection allow for removal of large, flat sessile polyps. Successful EMR is dependent on expanding the submucosal space to create adequate lift of the polyp to facilitate tissue capture and to avoid perforation and excess bleeding. ORISE gel (Boston Scientific) is a submucosal lifting agent currently in use in the United States. Methods We present three cases of gastrointestinal specimens obtained using ORISE gel. Histological analysis with hematoxylin and eosin revealed submucosal amorphous deposits that appeared to be mucin. Due to the concern for malignancy, additional stains were performed, including periodic acid–Schiff with diastase digestion (DPAS) to identify mucin. DPAS staining for mucin was negative, indicating the mucinous-appearing amorphous material seen on hematoxylin and eosin staining was not mucin but a likely remnant ORISE gel used during EMR. Additional immunohistochemical stains for epithelial cells (cytokeratin AE1/AE3) were also performed to exclude the presence of infiltrating tumor cells. Conclusion These three cautionary cases reveal the importance of good communication between endoscopists and pathology. In an effort to avoid overdiagnosis and/or the usage of unnecessary additional stains, pathologists should be alerted of ORISE gel usage.

Potential clinical complications of OriseTM gel use, a new submucosal lifting agent: experience from a tertiary care center and review of the literature

“…Recent publications have reported similar side-effects ( Table 2 ). In the 3 case examples presented by Cypher et al , it was observed that, after EMR, Orise™ gel remnants led to a histopathologically mucin-like accumulation, but this was eliminated by PAS, PAS-D, and cytokeratin negative staining [ 11 ]. In a case series containing 4 cases published by Westbrook et al , immediately after Orise™ gel injection, a pale, blue-grey, mucin-like appearance was observed on H&E staining, but this accumulation was mucicarmine-positive and PAS, PAS-D, trichrome, and Alcian blue-negative [ 12 ].…”

Histologic changes with a novel submucosal lifting gel for endoscopic resection: more than just a lift

“…Our group and others have shown that the amorphous pale acellular ORISE gel can mimic mucin on histologic examination. 2,3 Although Olivas et al 1 indicate that ORISE gel was identified as a procedural artifact in all of their cases without requiring special stains, we strongly recommend that stains for PAS and mucicarmine be considered whenever these histologic findings are encountered so as to avoid a misdiagnosis of mucinous adenocarcinoma. Certain histologic features, including submucosal hemorrhage, which we have witnessed in our practice and have been previously reported, were not identified in this study.…”

“…However, there is a thought that trainee participation during ERCP might increase the fluoroscopy time, raising a safety concern. 2,3 Moreover, there are no available data regarding the effects of trainee participation on ERCP total procedural and fluoroscopy times. Therefore, we performed a large-scale analysis from a real-world national endoscopic database, Clinical Outcomes Research Initiative (CORI) v. 4 (2009-2014) to determine the impact of trainee involvement on ERCP procedure times.…”

A Focused Review on Advances in Risk Stratification of Malignant Polyps

“…Awareness of Orise injections performed during the procedure and the visualization of uniform graypink material in the submucosa without associated stromal or inflammatory responses are helpful clues to avoid the diagnostic pitfall. In doubtful cases, a mucin stain such as PAS/D stain will prove useful, as Orise is PAS/D negative in the polypectomy specimen removed immediately after injection [140].…”