Table 2.

WHO classification of neuroendocrine tumors with sensitivities of the principal tissue markers

Grade	Lung/thymusa	GEP-NETb	Sensitivity, %
			CgA		CK fr		proGRP		NSE
			lung	GEP	lung	GEP	lung	GEP	lung	GEP
Low	carcinoid	neuroendocrine neoplasia, grade 1	60	50	28	29	25	15	16	17
Intermediate	atypical carcinoid	neuroendocrine neoplasia, grade 2	73	63	46	38	59	75	36	63
		neuroendocrine carcinoma, grade 3
		small-cell carcinoma
	small-cell carcinoma	neuroendocrine carcinoma, grade 3 large-cell neuroendocrine carcinoma	33	54	59	70	76	54	48	54
High	large-cell neuroendocrine carcinoma	mixed neuroendocrine adenocarcinoma	59	67	65	36	53	17	53	75

^a2000 classification.

^b2010 classification.

GEP-NET = Gastroenteropancreatic neuroendocrine tumor.