Endoscopic techniques for diagnosis and treatment of gastro-entero-pancreatic neuroendocrine neoplasms: Where we are

Table 1 Available endoscopic treatment options for gastro-entero-pancreatic neuroendocrine neoplasms

Primary site	Tumor characteristics	Endoscopic management
Stomach	Type I < 5 mm	Surveillance
	Type I ≥ 5 mm	Resection (EMR, ESD)
	Type II
	Type III	Resection (EMR, ESD)1
	G1-G2
	< 10 mm
Duodenum	< 10 mm2	Resection (EMR, ESD)
	G1
	No muscularis mucosae invasion
	No periampullary
Pancreas	≤ 20 mm	Surveillance; EUS-guided RFA; EUS-guided ethanol injection
	G1-low G2
	Non-functioning
	No bile/pancreatic duct compression
	Functioning tumors, not suitable for surgery	EUS-guided ethanol injection
	The patient refuses the surgical approach
Rectum	< 10 mm3	Resection (EMR, mEMR, ESD, EFTR)
	G1-G2
	No muscularis mucosae invasion

¹Endoscopic resection of type III gastric NENs can be considered curative only in case of histological complete resection.

²There is still controversy regarding the management of duodenal NENs between 10 and 20 mm.

³Treatment of rectal NENs with a size of 10–19 mm should be chosen after assessing the stage and the grade of differentiation.

G: Grading according to WHO classification; EMR: Endoscopic mucosal resection; mEMR: Modified endoscopic mucosal resection; ESD: Endoscopic submucosal dissection; EFTR: Endoscopic full-thickness resection; EUS: Endoscopic ultrasound.