Observational prospective multicenter study to investigate efficacy and safety of endoscopic full thickness resection in the lower GI tract using a novel over-the-scope full thickness resection device.

The FTRD ("Full Thickness Resection Device", Ovesco Endoscopy, Tübingen, Germany) is an over the scope device consisting of a transparent cap with a preloaded monofilament snare and and a 14 mm modified Over-the-scope Clip. The device is CE marked for full thickness resection in the lower GI tract.

The study was designed to investigate efficacy and safety of this device for full thickness resection of colorectal lesions.

Inclusion Criteria:

• Age > 18 y
• Adenoma with negtive lifting sign
• Adenoma involving or next to a diverticulum
• Adenoma involving or next to the appendical orifice
• T1 carcinoma with indication for endoscopic (re-)resection
• Subepithelial colorectal tumor with indication for resection

Exclusion Criteria:

• Lesions >3 cm
• T1 carcinomas with known high-risk features (submucosal infiltration>1000 um, invasion of lymphatic vessels, poor differentiation (G3))
• Lesions in the upper GI tract
• Patients with colorectal stenosis
• Patinets not able to undergo informed consent
• Pregnancy
• Patients with urgent indication for dual thrombocyte aggregation inhibition

Patients with colorectal lesions which are difficult or impossible to resect with conventional endoscopic methods