3D-Printed vs Commercial Distal Caps for ESD: Multicenter Randomized Ex Vivo Noninferiority Trial (ENDOPRINT Trial)

Distal attachment caps enhance visualization and traction during endoscopic submucosal dissection (ESD) but may influence procedural ergonomics. We conducted the multicenter ENDOPRINT randomized comparative feasibility study with a prespecified noninferiority hypothesis to compare a custom 3D-printed cap made from flexible medical-grade resin with a standard commercial cap using an ex vivo porcine model across tertiary centers in Prague, Olomouc, and Boston.

Across 3 centers, 99 ex vivo ESD procedures (33 per site) were randomized 1:1 to a 3D-printed cap or a commercial Olympus cap. The primary end point was procedure time; secondary end points included lesion size, en bloc resection, technical success, ergonomic parameters (visibility, scope manipulation, tissue retraction), cap handling, and adverse events. Group allocation was balanced across sites.

Median procedure time was identical for both caps (17.3 minutes each; P = 0.952), remaining well within the predefined 20% noninferiority margin, and lesion sizes were comparable between groups. En bloc resection and technical success were achieved in 100% of cases in both arms. Ergonomic assessments favored the 3D-printed cap, with higher operator ratings for visibility, manipulation, and tissue retraction, all with P < 0.001 and consistent across all centers. Adverse events were uncommon and similar between groups. Procedure time correlated with lesion size ( P = 0.001).

The ENDOPRINT trial demonstrated that a 3D-printed distal cap is as efficient and safe as a commercial cap during ESD, while providing superior visibility, scope control, and tissue traction. These results support the potential of customizable 3D-printed accessories with substantially lower per-unit material costs compared with commercial devices for clinical practice and training, warranting further in vivo validation and formal cost-effectiveness studies.