2002 American Joint Committee on Cancer (AJCC) TNM Staging System for the Colon and Rectal Cancer

TX: Primary tumor cannot be assessed
T0: No evidence of primary tumor
Tis: Carcinoma in situ: intraepithelial or invasion of lamina propria
T1: Tumor invades submucosa
T2: Tumor invades muscularis propria
T3: Tumor invades through the muscularis propria into the subserosa, or into nonperitonealized pericolic or perirectal tissues
T4: Tumor directly invades other organs or structures, and/or perforates visceral peritoneum

NX Regional lymph nodes cannot be assessed
N0 No regional lymph node metastasis
N1 Metastasis in 1 to 3 regional lymph nodes
N2 Metastasis in 4 or more regional lymph nodes

Stage 0: Tis N0 M0
Stage I: T1 N0 M0, T2 N0 M0
Stage IIA: T3 N0 M0
Stage IIB: T4 N0 M0
Stage IIIA: T1-T2 N1
Stage IIIB: T3-T4 N1 M0
Stage IIIC: Any T N2 M0
Stage IV: Any T Any N M1