New insights in diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms

Table 1 World Health Organization classification for gastroenteropancreatic neuroendocrine neoplasms¹

	Differentiation	Mitotic rate (%)	Ki-67 proliferation index (%)
G1 NET	Well-differentiated	< 2	< 3
G2 NET	Well-differentiated	2-20	3-20
G3 NET	Well-differentiated	> 20	> 20
SCNEC	Poorly-differentiated	> 20	> 20
LCNEC	Poorly-differentiated	> 20	> 20
MiNEN	Well- or poorly-differentiated	Variable	Variable

NET: Neuroendocrine tumor; SCNEC: Small cell neuroendocrine carcinoma; LCNEC: Large cell neuroendocrine carcinoma; MiNEN: Mixed neuroendocrine-non-neuroendocrine neoplasm.

¹Data derived from Klimstra et al[1].