| C20 | Malignant neoplasm of rectum |
| C21 | Malignant neoplasm of anus and anal canal |
| C21.0 | Malignant neoplasm of anus, unspecified |
| C21.1 | Malignant neoplasm of anal canal |
| C21.2 | Malignant neoplasm of cloacogenic zone |
| C21.8 | Malignant neoplasm of overlapping sites of rectum, anus and anal canal |
| C22 | Malignant neoplasm of liver and intrahepatic bile ducts |
| C22.0 | Liver cell carcinoma |
| C22.1 | Intrahepatic bile duct carcinoma |
| C22.2 | Hepatoblastoma |
| C22.3 | Angiosarcoma of liver |
| C22.4 | Other sarcomas of liver |
| C22.7 | Other specified carcinomas of liver |
| C22.8 | Malignant neoplasm of liver, primary, unspecified as to type |
| C22.9 | Malignant neoplasm of liver, not specified as primary or secondary |
| C23 | Malignant neoplasm of gallbladder |
| C24 | Malignant neoplasm of other and unspecified parts of biliary tract |
| C24.0 | Malignant neoplasm of extrahepatic bile duct |
| C24.1 | Malignant neoplasm of ampulla of Vater |
| C24.8 | Malignant neoplasm of overlapping sites of biliary tract |
| C24.9 | Malignant neoplasm of biliary tract, unspecified |
| C25 | Malignant neoplasm of pancreas |
| C25.0 | Malignant neoplasm of head of pancreas |
| C25.1 | Malignant neoplasm of body of pancreas |
| C25.2 | Malignant neoplasm of tail of pancreas |
| C25.3 | Malignant neoplasm of pancreatic duct |
| C25.4 | Malignant neoplasm of endocrine pancreas |
| C25.7 | Malignant neoplasm of other parts of pancreas |
| C25.8 | Malignant neoplasm of overlapping sites of pancreas |
| C25.9 | Malignant neoplasm of pancreas, unspecified |
| C26 | Malignant neoplasm of other and ill-defined digestive organs |
| C26.0 | Malignant neoplasm of intestinal tract, part unspecified |
| C26.1 | Malignant neoplasm of spleen |
| C26.9 | Malignant neoplasm of ill-defined sites within the digestive system |