Management of ampullary neoplasms: A tailored approach between endoscopy and surgery

Table 1 Staging classification of the ampullary neoplasms according to the American Joint Committee on Cancer TNM classification, 7^th edition[47]

T = Primary Tumor
TX	Primary tumor cannot be assessed
T0	No evidence of primary tumor
Tis	Carcinoma in situ
T1	Tumor limited to ampulla of Vater or sphincter of Oddi
T2	Tumor invades duodenal wall
T3	Tumor invades pancreas
T4	Tumor invades peripancreatic soft tissue or other adjacent organs or structures other than pancreas
N = Regional Lymph Nodes
NX	Regional lymph nodes cannot be assessed
N0	No regional lymph node metastasis
N1	Regional lymph node metastasis
M = Distant Metastasis
MX	Distant metastasis cannot be assessed
M0	No distant metastasis
M1	Distant metastasis
G = Histologic Grade
GX	Grade cannot be assessed
G1	Well differentiated
G2	Moderate differentiated
G3	Poorly differentiated
G4	Undifferentiated
Stage	T	N	M
0	Tis	N0	M0
IA	T1	N0	M0
IB	T2	N0	M0
IIA	T3	N0	M0
IIB	T1	N1	M0
	T2	N1	M0
	T3	N1	M0
III	T4	Any N	M0
IV	Any T	Any N	M1