The American Joint Committee on Cancer uses the TNM system to stage gallbladder cancer as follows: (Adapted from AJCC 6 th edition, 2002)
Primary tumor (T)
• TX - Primary tumor cannot be assessed
• T0 - No evidence of primary tumor
• Tis - Carcinoma in situ
• T1 - Tumor invades mucosa or muscle layer
• T2 - Tumor invades perimuscular connective tissue
• T3 - Tumor invades/perforates the serosa and/or directly invades the liver and/or one other adjacent organ or structure
• T4 - Tumor invades main portal vein or hepatic artery or >2 adjacent organs
Regional lymph node (N)
• NX - Regional lymph nodes cannot be assessed
• N0 - No metastases in regional lymph nodes
• N1 – Regional lymph node metastases
Metastases (M)
• MX - Presence of metastases cannot be assessed
• M0 - No distant metastases
• M1 - Distant metastases
TNM Groupings by Stage
Stage T N M
Stage 0 Tis N0 M0
Stage IA T1 N0 M0
Stage IB T2 N0 M0
Stage IIA T3 N0 M0
Stage IIB T1
T2
T3 N1
N1
N1 M0
M0
M0
Stage III T4 Any N M0
Stage IV Any T Any N M1
