T Primary tumor TX Primary tumor cannot be assessed T1 Tumor invades mucosa or muscle layer T1a, tumor invades mucosa T1B, tumor invades muscle T2 Tumor invades perimuscular connentive tissue, no extension beyond serosa or into liver T3 Tumor invades beyond serosa or into one adjacent organ or both (extension < 2cm into liver= T4 Tumor extend > 2cm into liver and/or into two or more adjacent organs (stomach, duodenum, colon, pancreas, omentum, extrahepatic bile ducts)
N Regional lymph nodes Nx Regional lymph nodes cannot be assessed No No regional lymph node metastasis N1a, Metastasis in cystic duct, pericholedochel, and/or gastrohepatie lymph nodes N1b, Metastasis in peripancreatic, periduodenal, periportal, celiac, and/or superior mesenteric artery lymph nodes
M Distant metastasis Mx Presence of distant metastasis cannot be assessed M0 No distant metastasis M1 Distant metastasis