Abstract
Background and study aims Recently, a new external additional working channel (AWC) was introduced by which
conventional endoscopic mucosal resection (EMR) can be improved to a technique termed
“EMR+”. We first evaluated this novel technique in comparison to classical EMR in
flat lesions.
Methods The trial was prospectively conducted in an ex vivo animal model with porcine stomachs
placed into the EASIE-R simulator. Prior to intervention, standardized lesions were
set by coagulation dots, measuring 1, 2, 3 or 4 cm.
Results Overall, 152 procedures were performed. EMR and EMR+ were both very reliable in 1-cm
lesions, each showing en bloc resection rates of 100 %. EMR+ en bloc resection rate
was significantly higher in 2-cm lesions (95.44 % vs. 54.55 %, P = 0.02), in 3-cm lesions (86.36 % vs. 18.18 %, P < 0.01) and also in 4-cm lesions (60.00 % vs. 0 %, P < 0.01). Perforations occurred only in EMR+ procedures in 4-cm lesions (3 of 20;
15 %).
Conclusions With its grasp-and-snare technique, EMR+ facilitates en bloc resection of larger
lesions compared to conventional EMR. In lesions 2 cm and larger, EMR+ has demonstrated
advantages, especially concerning en bloc resection rate. At 3 cm, EMR+ reaches its
best discriminatory power whereas EMR+ has inherent limits at 4 cm and in lesions
of that size, other techniques such as ESD or surgery should be considered.