Table 8. Primary Tumora

TXPrimary tumor cannot be assessed.
T0No evidence of primary tumor.
T1Tumor invades lamina propria or submucosa and size ≤2 cm.
T1aTumor size <1 cm in greatest dimension.
T1bTumor size 1–2 cm in greatest dimension.
T2Tumor invades muscularis propria or size >2 cm with invasion of lamina propria or submucosa.
T3Tumor invades through the muscularis propria into the subserosa or into nonperitonealized pericolic or perirectal tissues.
T4Tumor invades peritoneum or other organs.
For any T, add (m) for multiple tumors.

aReprinted with permission from AJCC: Neuroendocrine tumors. In: Edge SB, Byrd DR, Compton CC, et al., eds.: AJCC Cancer Staging Manual. 7th ed. New York, NY: Springer, 2010, pp 181-9.

From: Gastrointestinal Carcinoid Tumors Treatment (PDQ®)

Cover of PDQ Cancer Information Summaries
PDQ Cancer Information Summaries [Internet].
Bethesda (MD): National Cancer Institute (US); 2002-.

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