Small bowel carcinoid: Location isn’t everything!

Table 1 American Joint Committee on Cancer staging for small bowel carcinoid

Stage	TNM	Size or depth of invasion	Lymph node status	Distant metastases
0	TisN0M0	Carcinoma in-situ; tumor size < 0.5 mm	None	None
I	T1N0M0	Invasion into the lamina propria or submucosa; tumor size 1 cm or less	None	None
IIA	T2N0M0	Invasion into the lamina propria and/or submucosa and tumor size > 1 cm	None	None
		Invasion into the muscularis propria	None	None
IIB	T3N0M0	Invasion into the submucosa	None	None
IIIA	T4N0M0	Invasion into the serosa/visceral peritoneum or into nearby organ or structures	None	None
IIIB	T1-4N1M0	Any	Positive regional lymph nodes	None
IV	T1-4N0-1M1	Any	Any	Yes

Source: Ref[9,35], with permission.