Staging of colon cancer

Modified Duke Staging System
Modified Duke A
The tumor penetrates into the mucosa of the bowel wall but no further.
Modified Duke B
B1: tumor penetrates into, but not through the muscularis propria (the muscular layer) of the bowel wall.
B2: tumor penetrates into and through the muscularis propria of the bowel wall.
Modified Duke C
C1: tumor penetrates into, but not through the muscularis propria of the bowel wall; there is pathologic evidence of colon cancer in the lymph nodes.
C2: tumor penetrates into and through the muscularis propria of the bowel wall; there is pathologic evidence of colon cancer in the lymph nodes.
Modified Duke D
The tumor, which has spread beyond the confines of the lymph nodes (to organs such as the liver, lung or bone).
TNM Staging System (Tumor, Node, Metastisis)
Tumor
T1: Tumor invades submucosa.
T2: Tumor invades muscularis propria.
T3: Tumor invades through the muscularis propria into the subserosa, or into the pericolic or perirectal tissues.
T4: Tumor directly invades other organs or structures, and/or perforates.
Node
N0: No regional lymph node metastasis.
N1: Metastasis in 1 to 3 regional lymph nodes.
N2: Metastasis in 4 or more regional lymph nodes.
Metastasis
M0: No distant metastasis.
M1: Distant metastasis present.