Double-snare-assisted endoscopic mucosal resection of a rectal neuroendocrine tumor through a single-channel endoscope

Abstract

Figures

Schematic representation of the modified double-snare resection technique. a The resection snare was placed around the transparent cap on the outside of the endoscope. b The capture snare was introduced through the endoscope channel. c The lesion was grasped and lifted by the capture snare. d The resection snare was released, and placed around the base of the lesion.

Endoscopic resection of a rectal neuroendocrine tumor (NET) using the modified double-snare resection technique. a A subepithelial tumor-like lesion was detected in the rectum with typical features of NET. b The lesion was grasped and lifted by the capture snare. c The resection snare was released and placed around the base. d The wound was clean and small after resection. e The wound was closed with clips. f The specimen was intact.

Pathology demonstrated a neuroendocrine tumor. a Hematoxylin and eosin staining. b–d Immunohistochemical findings: b Syn, c CD56, d SSTR2.

Full text

Endoscopic resection is the preferred treatment for small rectal neuroendocrine tumors (NETs) without evidence of metastasis 1 . The double-snare resection (DSR) technique using a double-channel endoscope has recently been reported to be a simple, safe, and inexpensive method of resecting rectal NETs 2 . However, the double-channel endoscope is not available in many endoscopy centers. We describe a new modified double-snare resection technique through a single-channel endoscope ( Fig. 1 , Video 1 ).

Schematic representation of the modified double-snare resection technique. a The resection snare was placed around the transparent cap on the outside of the endoscope. b The capture snare was introduced through the endoscope channel. c The lesion was grasped and lifted by the capture snare. d The resection snare was released, and placed around the base of the lesion.

Endoscopic mucosal resection with a modified double-snare technique for the treatment of a rectal neuroendocrine tumor.Video 1

An 80-year-old man underwent colonoscopy because of constipation. A subepithelial tumor-like lesion was detected in the rectum with typical features of NET ( Fig. 2 a ). The lesion was resected through the modified DSR technique in the following steps. First, a polypectomy snare (“resection snare”) was placed around the transparent cap on the outside of the endoscope. The steel ring was tightened before entering the rectum. Next, a second snare (“capture snare”) was introduced through the endoscope channel after entering the rectum. The lesion was grasped and lifted by the capture snare ( Fig. 2 b ). Then, the resection snare was released, passed over the capture snare, and placed around the base of the lesion ( Fig. 2 c ). The lesion was completely resected by the resection snare using cutting electrosurgical current and was taken out by the capture snare. A clean and small wound was seen ( Fig. 2 d ) and closed with clips ( Fig. 2 e ). En bloc resection was achieved without adverse events ( Fig. 2 f ).

Endoscopic resection of a rectal neuroendocrine tumor (NET) using the modified double-snare resection technique. a A subepithelial tumor-like lesion was detected in the rectum with typical features of NET. b The lesion was grasped and lifted by the capture snare. c The resection snare was released and placed around the base. d The wound was clean and small after resection. e The wound was closed with clips. f The specimen was intact.

The pathology showed NET, G1, with a maximum tumor diameter of 7 mm (ly0, v0, pHM0, pVM0) ( Fig. 3 a ). Immunohistochemical staining showed the tumor cells were positive for Syn ( Fig. 3 b ), CD56 ( Fig. 3 c ), and SSTR2 ( Fig. 3 d ).

Pathology demonstrated a neuroendocrine tumor. a Hematoxylin and eosin staining. b–d Immunohistochemical findings: b Syn, c CD56, d SSTR2.

The modified DSR technique through a single-channel endoscope incorporates the advantages of the DSR technique and previously reported clip-and-snare-assisted EMR technique 3 . It is simple to perform, saves time and cost, and can be achieved with only a single-channel endoscope.

Endoscopy_UCTN_Code_CCL_1AD_2AJ