Histologic changes caused by injection of a novel submucosal lifting agent for endoscopic resection in GI lesions

Submucosal injection fluid and tattoo agents

BACKGROUND AND AIMS

EMR and endoscopic submucosal dissection (ESD) are minimally invasive endoscopic techniques, developed for the removal of benign and early malignant lesions throughout the GI tract. Submucosal injection of a marking agent can help to identify lesions during surgery. Endoscopic resection frequently involves "lifting" of the lesions by injection of a substance within the submucosal space to create a cushion for safe resection. This review summarizes the current techniques and agents available for endoscopic marking and lifting of GI tract lesions.

METHODS

The MEDLINE database was searched through April 2023 for relevant articles related to the lifting and marking aspect of EMR by using key words such as "endoscopy" or "endoscopic" combined with "marking," "tattoo," and "lifting." The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy.

RESULTS

This technology review describes the techniques for endoscopic tattoo placement and submucosal lifting, along with currently available agents, safety, and costs.

CONCLUSIONS

Endoscopists performing EMR and ESD have several choices in submucosal injection materials for lifting and marking agents for tattoos. These may be commercially prepared agents or off-the-shelf materials with or without additives to facilitate visualization. A thorough understanding of the indications, techniques, properties of various agents, costs, and adverse events is necessary in choosing the appropriate materials and technique to optimize lesion resection in EMR and ESD.

Adverse Tissue Reactions to Orise Gel During Endoscopic Mucosal Resection and Dissection

BACKGROUND

To facilitate endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD), submucosal injection of lifting agents (LAs) is frequently used. ORISE™ gel, approved in 2018 by the US Food and Drug Administration (FDA), has been commonly utilized until recently. Its use grew rapidly due to its practical pre-filled syringe, prolonged lift effect, and ideal coloration. However, it has been noted to cause unexpected tissue reactions, described as "giant cell reaction" (GCR), which can obscure both macroscopic and microscopic views, potentially interfering with pathological evaluation. This study aims to describe the adverse effects of ORISE™ gel.

METHODS

This retrospective study analyzed pathology specimens from all consecutive patients who received ORISE™ injections for attempted polyp removal and subsequently underwent segmental colon resection at our center between 2019 and 2022. Descriptive analysis was performed.

RESULTS

A total of 45 patients were included, with 38% (n=17) being female and a median age of 66 years. The indications for surgery included adenocarcinoma in 14 patients (31%), suspected malignancy in 3 patients (7%) who had benign GCR-induced masses, and other indications in 28 patients, such as large polyps or recurrent polyps after initial endoscopic treatment. Surgical procedures included right hemicolectomy (44%), low anterior resection (13%), left colectomy (11%), sigmoidectomy (7%), and abdominoperineal resection (4%). Histologic evidence of prior LA injection was seen in 31 patients (69%), with 24 of these exhibiting GCR. At final pathology, no residual neoplasm was found in 9 patients (18%), while 14 patients (31%) had adenocarcinoma [T1 (7), T2 (3), T3 (3), T4 (1)].

CONCLUSION

ORISE™ Gel interacts with various tissue layers of the colon, frequently resulting in GCR. This reaction and the potential subsequent mass effect formation can impact decision-making in the management of complex colorectal lesions. Further study into the cause and consequences of LA tissue reactions is warranted.

Gone but not forgotten: expanding the spectrum of ORISE (submucosal lifting agent) associated diagnostic pitfalls and complications

AIMS

A synthetic lifting agent, ORISE, used for endoscopic mucosal resections, has been recalled from the market since November 2022 due to clinical complications. Despite this, the impact of ORISE-associated complications is expected to persist in the foreseeable future. We present a large single institutional series of therapeutic resections from patients for whom ORISE was used for initial endoscopic procedures, highlighting the pitfalls and complications associated with its use.

METHODS

All specimens showing lifting agent granulomata (LAGs) associated with the use of ORISE were identified. The H&E slides were reviewed to define the morphological characteristics and extent of LAG in the intestinal wall and other organs. The clinical impression and gross findings were compared with the final pathological diagnosis.

RESULTS

34 cases (28 resections and 6 repeat endoscopic mucosal resection specimens) showed LAG. On microscopy, 20.5% showed no residual disease, 64.7% also showed residual precursor lesion and 14.7% also showed malignancy. In 64.2% of cases, a mass lesion was seen grossly but no malignancy was identified microscopically. ORISE was present in vascular spaces (n=9), lymph nodes (n=2), other organs such as appendix (n=1) and omentum/peritoneum (n=1). The major discordance between clinical impression (mass/neoplasm) and final pathology (no residual malignancy) was seen in 4/34 (11.8%) cases. LAGs were seen up to 10 months after the use of ORISE in the prior endoscopic procedure.

CONCLUSION

ORISE deposits may mimic residual/disseminated neoplasm and prompt inadvertent changes in surgical decisions. Awareness of this pitfall is essential to prevent unwarranted surgical resections in patients undergoing follow-up for endoscopically resected lesions.

Building the Toolbox of Devices to Optimize a Practice in Submucosal Endoscopy

Endoscopic submucosal dissection (ESD) is a technically complex and still evolving procedure. As a result, there are many advances in the technology and tools available to assist the endoscopist. This article delves into the various tools developed for ESD including electrosurgical knives, caps, injection agents, and traction devices. The authors discuss tools available as well as their respective pros, cons, and technical considerations for use. Overall, the choice of tools depends on a multitude of factors from availability, cost, lesion characteristics, and the endoscopist's familiarity and proficiency.

Assessment of submucosal distortion and mass effect seen at follow-up after colorectal EMR with ORISE (with video)

BACKGROUND AND AIMS

ORISE (Boston Scientific, Marlborough, Mass, USA) is a viscous gel used for submucosal injection. We noted anecdotally that ORISE is associated with submucosal distortion of EMR scars at follow-up.

METHODS

We blindly reviewed photographs of 30 consecutive EMR scars at follow-up after resections using ORISE and 30 resections using other agents. Distortion was scored on a scale of 0 (no submucosal distortion) to 5 (overt submucosal distortion).

RESULTS

The median submucosal distortion score at follow-up in ORISE cases was 3 (range, 0-5) versus 0 (range, 0-2) with other fluids (P < .001, Mann-Whitney U test) by 1 reviewer and 3 (range, 0-5) versus 2 (range, 0-5), respectively, by a second reviewer (P = .018). The kappa value for agreement in the submucosal distortion scores between the 2 experts was .148 for all photographs and .214 for the ORISE cases (overall minimal agreement).

CONCLUSIONS

ORISE can cause submucosal distortion in the region of EMR scars when they are viewed at follow-up. Such distortions must not be mistaken for submucosal tumor growth.

Bulking agents in gastrointestinal endoscopy: present applications and future advances

PURPOSE OF REVIEW

Bulking agents are inert materials injected into an organ to affect the physical properties of the organ for a therapeutic purpose. Various agents have been developed to aid in the treatment of diseases like gastroesophageal reflux disease (GERD), fecal incontinence, obesity, malignancy, hemostasis, and tissue dissection. Here, we review the state of the art in bulking agents in gastrointestinal endoscopy, past failures, current limitations, and where we see the field heading in the future.

RECENT FINDINGS

Though bulking agents have been trialed for various different gastrointestinal diseases, there are currently limited uses in gastrointestinal endoscopy. Though various agents have been trialed for GERD, numerous complications and adverse events have limited its current use. However, for the treatment of fecal incontinence endoscopic bulking agent therapy is a reasonable option. Though in early stages of exploration, bulking agent therapy for enteric protection from radiotherapy may be a promising tool to improve treatment of pancreatic cancer. Bulking agents for tissue dissection have substantially improved lifting agents and complex polyp removal. Bulking agent therapy has not really been explored for endoscopic bariatric therapy or hemostasis but may be a fruitful area for exploration in the future.

SUMMARY

Bulking agent therapy has been trialed for various gastrointestinal diseases with mixed success. There is currently a therapeutic roll in the endoscopic management of fecal incontinence and tissue dissection. A future role in the treatment of GERD, obesity, malignancy, and hemostasis seem feasible.

Polypectomy for Large Polyps with Endoscopic Mucosal Resection

Beginning in 1955, when the saline injection was first described to prevent transmural injury during polyp fulguration, endoscopic mucosal resection (EMR) has grown exponentially, both in scope and in practice. Because EMR is an organ-preserving technique even for large polyps, this allows for comparable outcomes to surgery, but substantially improved cost savings and significantly reduced morbidity and mortality. To achieve this, however, one must master the 4 fundamental components that are critical to the success of EMR- time, team, tools, and technique. This article aims to provide a compendium of state of the art updates within the field of endoluminal resection.

New Kids on the Block

CONTEXT.—

With the increasing development and use of iatrogenic agents, pathologists are encountering more novel foreign materials in retrieved gastrointestinal specimens. These colorful and unusual-appearing foreign materials can pose a diagnostic dilemma to those unaware of their morphology, especially if the relevant clinical history is lacking.

OBJECTIVE.—

To discuss the histopathologic features, clinical scenarios and significance, and differential diagnosis of relatively recently described, yet quickly expanding, family of iatrogenic agents that can present as foreign materials in gastrointestinal specimens-pharmaceutical fillers (crospovidone and microcrystalline cellulose), submucosal lifting agents (Eleview and ORISE), lanthanum carbonate, hydrophilic polymers, OsmoPrep, yttrium 90 microspheres (SIR-Sphere and TheraSphere), and resins (sodium polystyrene sulfonate, sevelamer, and bile acid sequestrants).

DATA SOURCES.—

We collate the findings of published literature, including recently published research papers, and authors' personal experiences from clinical sign-out and consult cases.

CONCLUSIONS.—

Correct identification of these iatrogenic agents is important because the presence of some novel agents can explain the histopathologic findings seen in the background specimen, and specific novel agents can serve as diagnostic clues to prompt the pathologist to consider other important and related diagnoses. Awareness of even biologically inert agents is important for accurate diagnosis and to avoid unnecessary and expensive diagnostic studies.

Histologic mimics and diagnostic pitfalls of gastrointestinal endoscopic lifting media, ORISE™ gel and Eleview®

Synthetic lifting media, ORISE™ gel and Eleview®, are increasingly used in gastrointestinal endoscopy, but neither comparative features nor pitfalls are well-established. Media histopathology, morphologic mimics, and complications are described, along with helpful stains and endoscopist media preference. A 3-year retrospective search was performed. A total of 123 cases (108 endoscopies and 15 subsequent surgeries) were identified. ORISE gel was used in 86 (79.6%), Eleview in 20 (13.9%), and others in 7 (6.5%). ORISE gel was histologically identified in 58.1% (n = 50) of endoscopic specimens and all 15 resections. Eleview media were not detected histologically. ORISE gel mimicked mucin in hematoxylin and eosin-stained biopsies, concerning for adenocarcinoma misdiagnosis and/or upstaging, but did not stain for mucin. Acid-fast bacterial staining highlights ORISE gel for specific and definitive identification. In resections, ORISE evolves into an amorphous eosinophilic material, often with exuberant giant cell reaction and transmural bowel penetration. Polyp formation leads to polypectomy in one patient, and operative lesions concerning for adenocarcinoma resulted in frozen sections in two patients. ORISE gel mimics mucin, malignant masses, amyloid, pulse granulomata, elastofibromas, and infectious granulomata. No significant endoscopist media preference was identified. Recognition of ORISE gel in tissues eliminates multiple pitfalls. Eleview was not detectable, yielded none of the pitfalls seen with ORISE gel, and, on our survey, has equivalent endoscopist acceptance. In this largest published series to date, Eleview is clearly preferable to ORISE gel.

Submucosal lifting agent ORISE gel causes extensive foreign body granuloma post endoscopic resection

BACKGROUND

Submucosal injection of lifting solution is often performed to facilitate endoscopic mucosal resection or endoscopic submucosal dissection. ORISE^TM gel is a synthetic solution recently approved by the US Food and Drug Administration (FDA) in 2018 for use as submucosal lifting solution for endoscopic resection procedures and has gained popularity for its convenient pre-filled syringe. However, here the present two cases show that ORISE^TM gel induces marked foreign body giant cell granulomatous reaction in the submucosa and muscularis propria following endoscopic resection.

METHODS AND RESULTS

A 73-year-old female underwent laparoscopic right colectomy after her initial endoscopic polypectomy of a hyperplastic polyp, and a 78-year-old male had partial gastrectomy following endoscopic mucosal resection of an invasive adenocarcinoma. Both patients had submucosal injection of ORISE^TM gel during endoscopic procedures, and the surgical resection specimens showed ORISE^TM gel deposition and extensive foreign body giant cell granulomatous reaction in the submucosa and muscularis propria.

CONCLUSION

These cases raise the awareness that ORISE^TM gel stimulates extensive foreign body reaction at the injection site, and the further consequence is still unclear.