Time to give up traditional methods for the management of gastrointestinal neuroendocrine tumours

Table 1 Classification and grading criteria for neuroendocrine neoplasms

Type of NET	Differentiation	Grade	Mitotic Index	Proliferative index: Ki-67
NET, grade 1	Well-differantiated	Low	< 2	< 3
NET, grade 2		Intermediate	2-20	3-20
NET, grade 3		High	> 20	> 20
NEC, grade 3	Poorly-differantiated	High	> 20	> 20
Small cell type; Large cell type
MINENs	Well or poorly differentiated	Variable

MINEN: Mixed neuroendocrine neoplasm; NET: Neuroendocrine tumor.

Table 2 General characteristics of gastric neuroendocrine tumors[60,65]

	Type 1	Type 2	Type 3
Distribution, %	70-80	5-6	15-30
Gender predominance	F > M	F = M	M > F
Associated disease	Atrophic gastritis, pernicious anemia	ZES/MEN1	None
Location: gastric	Body, fundus	Body, fundus	Anywhere
Tumor
Number	> 1	>1	1
Size: Generally	< 1 cm	< 1 cm, > 1 cm	> 2 cm
Mucosa	Atrophic	Hypertrophic	Normal
Gastrin level	Hypergastrinemia	Hypergastrinemia	Normal
Gastric pH	High	Low	Normal
Treatment	Endoscopic, Surgery	Endoscopic, Surgery	Surgery, LND
Prognosis, survival %	100	60-90	50

F: Female; LND: Lymph node dissection; M: Male; MEN1: Multiple endocrine neoplasia type 1; ZES: Zollinger Ellison Syndrome.