T: primary tumor
TXPrimary tumor cannot be assessed
T0No evidence of primary tumor
TisCarcinoma in situ / high-grade dysplasia
T1aTumor invades lamina propria or muscularis mucosae
T1bTumor invades submucosa
T2Tumor invades muscularis propria
T3Tumor invades subserosa
T4aTumor perforates serosa
T4bTumor invades other adjacent structures (spleen, transverse colon, liver, diaphragm, pancreas, abdominal wall, adrenal gland, kidney, small intestine, retroperitoneum)
N: regional lymph nodes
NXRegional lymph nodes cannot be assessed
N0No regional lymph node metastasis
N1Metastasis in 1?2 regional lymph nodes
N2Metastasis in 3?6 regional lymph nodes
N3aMetastasis in 7-15 regional lymph nodes
N3bMetastasis in 16 or more regional lymph nodes
M: distant metastasis
M0No distant metastasis
M1Distant metastasis