| |
Definition |
| T stage |
| Tx |
No information about local tumour infiltration available |
| Tis |
Tumour restricted to mucosa, no infiltration of lamina muscularis mucosae. |
| T1 |
Infiltration through lamina muscularis mucosae into submucosa, no infiltration of lamina muscularis propria |
| T2 |
Infiltration into, but not beyond, lamina muscularis propria |
| T3 |
Infiltration into subserosa or non‐peritonealised pericolic or perirectal tissue, or both; no infiltration of serosa or neighbouring organs |
| T4a |
Infiltration of the serosa |
| T4b |
Infiltration of neighbouring tissues or organs |
| N stage |
| Nx |
No information about lymph node involvement available |
| N0 |
No lymph node involvement |
| N1a |
Cancer cells detectable in 1 regional lymph node |
| N1b |
Cancer cells detectable in 2 to 3 regional lymph nodes |
| N1c |
Tumour satellites in subserosa or pericolic or perirectal fat tissue, regional lymph nodes not involved |
| N2a |
Cancer cells detectable in 4 to 6 regional lymph nodes |
| N2b |
Cancer cells detectable in 7 or greater regional lymph nodes |
| M stage |
| Mx |
No information about distant metastases available |
| M0 |
No distant metastases detectable |
| M1a |
Metastasis to 1 distant organ or distant lymph nodes |
| M1b |
Metastasis to more than 1 distant organ or set of distant lymph nodes or peritoneal metastasis |
