Colorectal Cancer stages
1. Older colorectal cancer stages is based on Dukes staging system.
Stage 1: (Dukes'A):
0) lesions limited to mucosal layer (carcinoma in situ).
1) invasion and submucosal lesions.
2) muscular lesion invading the intestinal wall.
Stage 2 (Dukes'B):
lesions and serosal invasion, or invasion and the surrounding tissues and organs, but en bloc resection can be together.
Stage 3 (Dukes'C):
1) with lesions near the lymph node metastasis (refer to the side or on the edge of blood vessel wall adjacent to lymph node metastasis).
2) with the supply of blood vessels and mesangial margin near the lymph node metastasis.
Stage 4 (Dukes'D):
1) with distant organ metastasis (such as liver, lung, bone, brain metastasis, etc.).
2) with distant lymph node metastasis (such as the supraclavicular lymph node metastasis, etc.), or the supply of blood vessels can not be the root of all lymph node metastasis resection.
3) with peritoneal disseminated widely, not all of resection. 4: The lesion has been widely invasive resection of adjacent organs were not all.
2. Today's most commonly used stages for colorectal cancer is the TNM staging system by AJCC.
T: The degree of invasion of the intestinal wall
T0 - no evidence of tumor
T1 - invasion through muscularis mucosa into submucosa
T2 - invasion through submucosa into the muscularis propria (i.e. proper muscle of the bowel wall)
T3 - invasion through the muscularis propria into subserosa but not to any neighbouring organs or tissues
T4 - invasion of surrounding structures (e.g. bladder) or with tumour cells on the free external surface of the bowel
N: the degree of lymphatic node involvement
N0 - no lymph nodes involved
N1 - one to three nodes involved
N2 - four or more nodes involved
M: the degree of metastasis
M0 - no metastasis
M1 - metastasis present
Colorectal cancer have four distinct stages and fifth stage is Recurrent Cancer.
Stage I: The cancer has spread beyond the innermost tissue layer of the colon wall to the middle layers.
Stage IIA: The Cancer has spread beyond the middle tissue layers of the colon wall or has spread to nearby tissues around the colon or rectum.
Stage IIB: The Cancer has spread beyond the colon wall into nearby organs or through the peritoneum or both. The peritoneum is the membrane that lines the walls of the abdominal cavity.
Stage IIIA: The Cancer has spread from the innermost tissue layer of the colon wall to the middle layers and has spread to as many as three lymph nodes.
Stage IIIB: The Cancer has spread to as many as three nearby lymph nodes and has spread beyond the middle tissue layers of the colon wall; or to nearby tissues around the colon or rectum; or beyond the colon wall into nearby organs or through the peritoneum or both.
Stage IIIC: The Cancer has spread to four or more nearby lymph nodes and has spread: to or beyond the middle tissue layers of the colon wall; or to nearby tissues around the colon or rectum; or to nearby organs or through the peritoneum or both.
Stage IV: The Cancer may have spread to nearby lymph nodes and has spread to other parts of the body, such as the liver or lungs.
Recurrent Cancer: that comes back again after treatment, in the colon or other part of the body.Even after successful treatment of colon cancer, regular check ups are necessary to catch any recurrent cancer early.