Current status of surgical management of patients with gastroenteropancreatic neuroendocrine neoplasms

Table 1 The 2019 World Health Organization classification for gastroenteropancreatic neuroendocrine neoplasms

Morphology	Grade	Mitotic count (2 mm2)1	Ki-67 index (%)2
Well-differentiated NETs	G1	< 2	< 3
	G2	2-20	3-20
	G3	> 20	> 20
Poorly-differentiated NECs		> 20	> 20

¹Of ten high power fields = 2 mm², at least 40 fields (at × 40 magnification) evaluated in areas of highest mitotic density.

²MIB1 antibody; percentage of 500-2000 tumour cells in areas with the highest nuclear labeling.

NET: Neuroendocrine tumour; NEC: Neuroendocrine cancer.

Table 2 Clinical trials for surgical intervention in neuroendocrine neoplasm with open recruitment

Study title	Resection of metastatic PNETs after induction system treatment	Single-cell sequencing and establishment of models in NEN	Endoscopic ultrasound-guided radiofrequency ablation for the treatment	Prophylactic cholecystectomy in midgut NET patients who require primary tumor surgery
Primary site	Pancreas	GEP NEN	Pancreas	Jejunum, ileum, proximal colon
Study type	Observational	Observational	Interventional	Interventional
Multicentric	No	No	Yes	Yes
Primary purpose	NA	NA	Treatment	Treatment
Allocation	NA	NA	NA	Randomized
Estimated enrollment	180 participants	200 participants	70 participants	100 participants
Estimated study completion date	July 25, 2025	December 2022	June 1, 2021	April 2025

NEN: Neuroendocrine neoplasm; PNET: Pancreatic neuroendocrine tumour; NET: Neuroendocrine tumour; GEP: Gastroenteropancreatic; NA: Non-announced.