There is currently no reliable evidence on the safety of CSP (cold snare polypectomy) / p-CSP (piecemeal CSP) for SNADT greater than 6mm.In this prospective historical controlled study, we intend to test the role of CSP / p-CSP in the treatment of pedicle less snadt greater than 6mm compared with EMR (endoscopic mucosal resection) / EPMR (endoscopic piecemeal mucosal resection).

Due to the possibility of malignant transformation of duodenal adenomatous lesions, endoscopic resection is recommended as far as possible. The European Society of endoscopy guidelines recommend cold snare polypectomy for superficial non ampullary duodenal tumors (SNADT) less than 6mm in diameter, while EMR (endoscopic mucosal resection) is recommended as a first-line endoscopic resection for other larger lesions. ESD (endoscopic submucosal dissection) is not considered as the standard treatment of duodenum due to its difficult operation and high complication rate.

In recent years, CSP (cold snare polypectomy) has been widely used in the colon. CSP is a safe alternative method of directly removing polyps with snare without electrifying. Reducing electrocoagulation can reduce the damage of peripheral blood vessels and intestinal wall, leading to decreased risk of delayed bleeding and perforation. CSP has gradually replaced EMR in the resection of colorectal lesions of appropriate size.

So far, there is no reliable evidence on the safety of CSP / p-CSP (piecemeal CSP) for SNADT greater than 6mm.In this prospective historical controlled study, we intend to test the role of CSP / p-CSP in the treatment of pedicle less snadt greater than 6mm compared with EMR / EPMR (endoscopic piecemeal mucosal resection).

Inclusion Criteria:

Experimental arm: CSP/p-CSP

1. Patients of age 18-75 years.
2. Lesion located in the duodenum.
3. Superficial non-ampullary duodenal tumors (SNADTs) (>6mm, Sessile).
4. Written informed consent.
5. Benign adenomatous surface features (Kudo III / IV, JNET(Japan NBI (narrow-band imaging) Expert Team) 2a).

Control arm: EMR/EPMR

1. Patients of age 18-75 years.
2. Lesion located in the duodenum.
3. Superficial non-ampullary duodenal tumors (SNADTs) (>6mm, Sessile).
4. Benign adenomatous surface features (Kudo III / IV, JNET 2a).
5. Received EMR/EPMR already.
6. Provided written informed consent for use of clinical information.

Exclusion Criteria:

Experimental arm: CSP/p-CSP

1. Absence of proper suspension of the anticoagulant/antiplatelet therapy prior to procedure according to usual pre-procedure recommendations according to the guidelines, or presence of coagulation disorder （PLT (platelet)<50×10^9 / L or INR (international normalized ratio)≥1.5) at the time of EMR/EPMR.
2. History of surgery in the stomach or duodenum (endoscopic surgery not included), or receiving chemotherapy/radiotherapy at the time of EMR/EPMR.
3. Pregnant or breast feeding at the time of EMR/EPMR.
4. Lesions involving the ampullary area.
5. Endoscopic features suggestive of submucosal invasion (Kudo Vi/n, JNET 2b / 3).
6. Scar of previous endoscopic procedures within 10mm around the lesion.

Control arm: EMR/EPMR

1. Absence of proper suspension of the anticoagulant/antiplatelet therapy prior to procedure according to usual pre-procedure recommendations according to the guidelines, or presence of coagulation disorder （PLT<50×10^9 / L or INR≥1.5)；.
2. History of surgery in the stomach or duodenum (endoscopic surgery not included), or receiving chemotherapy/radiotherapy.
3. Pregnant or breast feeding.
4. Lesions involving the ampullary area.
5. Endoscopic features suggestive of submucosal invasion (Kudo Vi/n, JNET 2b / 3).
6. Scar of previous endoscopic procedures within 10mm around the lesion.

Original data could be shared at request by email after publication

The data will be available after publication of the study

The shared data could be available by contacting Dr. Xin-Yang Liu at shmulxy@163.com.