Pancreatic acinar cell carcinoma: A comprehensive review

Table 3 American Joint Committee on Cancer 8^th Edition cancer staging for exocrine pancreatic tumor such as pancreatic acinar cell carcinoma

Stage	TNM	Description
0	Tis	Carcinoma in situ1
	N0	No regional lymph node metastases
	M0	No distant metastasis
IA	T1	T1 = Tumor is ≤ 2 cm in any direction
		T1a = Tumor is ≤ 0.5 cm in any direction
		T1b = Tumor is > 0.5 cm and < 1 cm in any direction
		T1c = Tumor is 1–2 cm in any direction
	N0	No regional lymph node metastases
	M0	No distant metastasis
IB	T2	Tumor is > 2 cm and ≤ 4 cm in any direction
	N0	No regional lymph node metastases
	M0	No distant metastasis
IIA	T3	Tumor is > 4 cm in any direction
	N0	No regional lymph node metastases
	M0	No distant metastasis
IIB	T1	T1 = Tumor is ≤ 2 cm in any direction
		T1a = Tumor is ≤ 0.5 cm in any direction
		T1b = Tumor is > 0.5 cm and < 1 cm in any direction
		T1c = Tumor is 1–2 cm in any direction
	N1	Metastasis in one to three regional lymph nodes
	M0	No distant metastasis
	T2	Tumor is > 2 cm and ≤ 4 cm in any direction
	N1	Metastasis in one to three regional lymph nodes
	M0	No distant metastasis
	T3	Tumor is > 4 cm in any direction
	N1	Metastasis in one to three regional lymph nodes
	M0	No distant metastasis
III	T1	T1 = Tumor is ≤ 2 cm in any direction
		T1a = Tumor is ≤ 0.5 cm in any direction
		T1b = Tumor is > 0.5 cm and < 1 cm in any direction
		T1c = Tumor is 1–2 cm in any direction
	N2	Metastasis in four or more regional lymph nodes
	M0	No distant metastasis
	T2	Tumor is > 2 cm and ≤ 4 cm in any direction
	N2	Metastasis in four or more regional lymph nodes
	M0	No distant metastasis
	T3	Tumor is > 4 cm in any direction
	N2	Metastasis in four or more regional lymph nodes
	M0	No distant metastasis
	T4	Regardless of tumor size, the cancer has grown outside the pancreas, into the nearby large blood vessels2
	Any N	NX = Regional lymph nodes cannot be assessed
		N0 = No regional lymph node metastases
		N1 = Metastasis in one to three regional lymph nodes
		N2 = Metastasis in four or more regional lymph nodes
	M0	No distant metastasis
IV	Any T	TX = Primary tumor cannot be assessed
		T0 = No evidence of primary tumor
		Tis = Carcinoma in situ1
		T1 = Tumor is ≤ 2 cm in any direction
		T1a = Tumor is ≤ 0.5 cm in any direction
		T1b = Tumor is > 0.5 cm and < 1 cm in any direction
		T1c = Tumor is 1–2 cm in any direction
		T2 = Tumor is > 2 cm and ≤ 4 cm in any direction
		T3 = Tumor is > 4 cm in any direction
		T4 = Regardless of tumor size, the cancer has grown outside the pancreas, into the nearby large blood vessels2
	Any N	NX = Regional lymph nodes cannot be assessed
		N0 = No regional lymph node metastases
		N1 = Metastasis in one to three regional lymph nodes
		N2 = Metastasis in four or more regional lymph nodes
	M1	Distant metastasis

¹Included in this category are high-grade pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm with high-grade dysplasia, intraductal tubulopapillary neoplasm with high-grade dysplasia, and mucinous cystic neoplasm with high-grade dysplasia.

²Celiac axis, superior mesenteric artery, and/or common hepatic artery are involved.

T: Primary tumor; N: Regional lymph node; M: Distant metastasis.