Colorectal cancer staging-
Primary tumor (T)
Tis Carcinoma in situ
T1 Tumor invades the submucosa
T2 Tumor invades the muscularis propia
T3 Tumor invades the perirectal fat
T4 Tumor directly invades adjacent organs, structures and/or perforates the visceral peritoneum
Regional lymph nodes (N)
Nx Tumor cannot be assessed
N0 No regional metastases
N1 Metastases in 1-3 nodes
N2 Metastases in ≥ regional lymph node
Distant Metastases
Mx distant metastases cannot be assessed
M0 No distant metastases
M1 Distant metastases
Staging
Stage 0 TisN0M0
Stage 1 T1-2N0M0
Stage IIA T3N0M0
Stage IIB T4N0M0
Stage IIIA T1-2N1M)
Stage IIIB T3-4N1M0
Stage IIIC Any TN2M)
Stage IV Any T Any N M1
NCI-estimated 5 year relative survival rates for localized colon cancer, lymph node negative, regional disease, lymph node positive, and distant, metastatic disease are 89.9%, 71.3% and 13.9&, respectively.
The 5 year survival rate for stge I and early-stage II is estimated at 97% with surgery alone.
Survival rate drops to 60% for high-risk stage II tumors (T4aN0) and down to 50% or less for stage IIT4N0 or stage III cancers.