Endoscopic submucosal dissection (ESD) is preferred resection method for advanced colonic
polyp due to its higher rates of en bloc and R0 resection which lead to higher curative
resection rate.1 In comparison to gastric ESD, colonic ESD is more challenging due to
colonic unique anatomy and configuration. Tumor of size ≥ 50 mm, spreading across ≥ two
folds, flexure locations have been described as strong predictors for difficulties during
colonic ESD.2 Redundant colon and looping during colonoscopy may preclude successful
advancement of the colonoscope and maintaining stable position for complex polyp removal.
Historically, various methods have been applied to facilitate colonoscopy and scope
advancement in challenging positions and redundant colonic loops such as application of
external pressure, exchange to pediatric colonoscope, torque-based reduction maneuvers,
and patient repositioning. However, despite these, scope tip stabilization could
potentially remain as a challenging and limiting factor for procedure progress and could
lead to a longer procedure time, sedation time and perhaps lower procedure success rate.
In comparison overtube-assisted colonoscopy allows for straightening of the colon to
decrease angulation and loop formation.3 Several variations of overtubes have been put to
use in the last few decades with comparable results such as single-balloon and
double-balloon enteroscope, spiral overtube-assisted colonoscopy and double-balloon
platform (DiLumenTM). DiLumen system consists of a plastic sheet fitting layer with two
balloon few inches from each other in the tip of the device facilitating the scope tip
stability. Most recently the efficacy of DiLumen platform were evaluated in a multicenter
study including 162 patients who underwent endoscopic resection of advanced polyps.4 In
this study technical success was achieved in 92% of patients without any device related
adverse event. 4 In this study using an overtube resulted in faster and more efficient
dissection.4 In a retrospective study of 88 polyps located within the proximal colon, ESD
with assistance of traditional single balloon overtube resulted in significantly less
perforation rate in polyps ≥ 40mm in the proximal colon, despite overall similar en bloc
and R0 resection rates comparison to conventional ESD.5 Most recently, a novel dynamic
rigidizing overtube (Pathfinder, Neptune Medical, Burlingame, Calif, USA) has been
introduced to face the challenges encountered during difficult colonoscopies and to
ensure scope stabilization during endoscopic mucosal resection (EMR) and ESD. The
overtube material is soft and pliable on flexible state, however when the vacuum is
applied the entire tube becomes 15 times stiffer.6 This unique feature of the device
provides scope flexibility during colonoscope introduction and entire device stability
when rigidizing system is applied.
Our team collected preliminary prospective data of 58 polyps removed by EMR (24.1%) and
ESD (75.9% ) with the assistance off rigidizing overtube. Technical success (ability to
complete the entire resection using the device) and clinical success (ability of
endoscopic removal of polyps without changing the initial resection intent) was achieved
100% and 90% of the time, respectively. On endoscopist feedback, the rigidizing overtube
was though to assist in resection in 98.3% of polyps, although the polyp was located in a
somewhat/very difficult location 81% of the time. For polyps in difficult locations, the
rigidizing overtube was able to maintain scope position without falling back even once,
55% of the time. This result was presented at the most recent Digestive Disease Week
conference in Chicago 2023 (p1932).
As this device has been put to use recently in the United States, published literature to
demonstrate its safety and efficacy in colonic ESD is lacking. The main aim of this study
is to compare the feasibility, safety efficacy, and clinical outcomes of colonic
endoscopic submucosal dissection (ESD) utilizing a novel rigidizing overtube called
Pathfinder® Endoscope Overtube (Neptune Medical, Burlingame CA, USA) device in comparison
to conventional ESD.