CLASSIFICATION AND STAGING OF LIVER CANCER (1) Histologic classification of liver and intrahepatic bile duct tumors (WHO 2005). Yuehua Wang, Department of General Surgery, Xuanwu Hospital, Capital Medical University Benign Epithelial tumors Benign Hepatocellular adenoma 8170/0 Focal nodular hyperplasia Intrahepatic cholangiocarcinoma 8160/0 Intrahepatic cholangiocarcinoma cystadenoma 8160/0 Biliary tract papillomatosis 8264/0 Malignant Hepatocellular carcinoma of the liver (hepatocellular carcinoma) 8170/3 Intrahepatic cholangiocarcinoma (peripheral cholangiocarcinoma) 8160/3 Cholangiocystadenoma 8161/3 Mixed hepatocellular carcinoma and cholangiocellular carcinoma 8180/3 Hepatoblastoma 8970/3 Undifferentiated carcinoma 8020/3 Non-epithelial tumors Benign Vascular smooth muscle lipomas 8860/0 Lymphangiomas and lymphangiomatosis 9170/3 Hemangiomas 9120/0 Infantile hemangioendotheliomas 9130/0 Malignant Epithelioid hemangioendotheliomas 9133/1 Angiosarcomas 9120/3 Embryonal sarcoma (undifferentiated sarcoma) 8991/3 Rhabdomyosarcoma 8900/3 Other Miscellaneous tumors Isolated fibrous tumors 8815/0 Teratomas 9080/1 Egg yolk sac tumors (endodermal sinus tumors) 9071/3 Carcinosarcomas 8980/3 Kaposi’s sarcoma 9140/3 Rhabdomyosarcoma 8963/3 Other Hematopoietic and lymphoid tumors Secondary tumors Abnormal epithelial changes Hepatocellular atypia (hepatocellular changes) Large-cell type (large-cell changes) Small-cell type (small-cell changes) Atypical hyperplastic nodules (adenomatous hyperplasia) Low-grade High-grade (atypical adenomatous hyperplasia) Bile ducts Abnormalities Hyperplasia (biliary epithelium and peribiliary glands) Atypical hyperplasia (biliary epithelium and pericholangiectatic glands) Intraepithelial carcinoma (carcinoma in situ) Miscellaneous lesions Mesenchymal malignant tumors Nodular changes (nodular anaplastic hyperplasia) Inflammatory pseudotumor (ii) Staging of hepatocellular carcinoma. 1. TNM staging (UICC /AJCC, 2010). T- Primary lesion Tx: Primary tumor cannot be determined T0: No evidence of primary tumor T1: Isolated tumor without vascular invasion T2: Isolated tumor,with vascular invasion or multiple tumors ≤5cm in diameter T3a: Multiple tumors >5cm in diameter T3b: Isolated tumor or multiple tumors invading the portal vein or major branches of the hepatic vein T4: Tumor directly invades the surrounding tissues, or results in perforation of the gallbladder or organs N- Regional lymph nodes Nx: lymph nodes in the region cannot be determined N0: no lymph node metastasis N1: regional lymph node metastasis M- Distant metastasis Mx: distant metastasis cannot be determined M0: no distant metastasis M1: with distant metastasis Staging: Stage I: T1N0M0 Stage II: T2N0M0 Stage IIIA: T3aN0M0 Stage IIIB: T3bN0M0 Stage IIIC: T4. N0M0 IVA: any T, N1M0 IVB: any T, any N, M1 TNM staging is mainly based on the size and number of tumors, vascular invasion, lymph node invasion, and the presence or absence of distant metastases, and is divided into I-IV, which reflects the severity of the tumors in ascending order; the advantage of this is that it describes in detail the development of hepatocellular carcinoma in a standardized manner; however, the degree of recognition of TNM staging is relatively low in international practice. However, the TNM staging is less recognized internationally because: ① most patients with hepatocellular carcinoma have severe cirrhosis, and the staging does not describe the liver function, while the treatment of HCC emphasizes the liver function compensation, and the liver function significantly affects the choice of treatment and the judgment of prognosis; ② vascular invasion, which is crucial to the treatment and the prognosis of HCC, is difficult to be judged accurately before treatment (especially before surgery); ③ the staging varies greatly from one version to another, and it is difficult to compare them; ③ the staging is not the same as that of other versions, and it is difficult to compare them with the others. (iii) TNM staging varies greatly from one version to another, making it difficult to compare and evaluate. 2. BCLC staging (Barcelona Clinical Liver Cancer Staging, 2010) (Table 1). Table 1 BCLC staging of HCC Stage PS score Tumor status Liver function status Number of tumors Tumor size Stage 0: Very early 0 Single <2 cm No portal hypertension Stage A: Early stage 0 Single 3 or less Any <3 cm Child-Pugh A-B Child-Pugh A-B Stage B: Intermediate stage 0 Multi-nodular tumor Any Child-Pugh A-B Stage C: Progressive stage 1-2 Portal invasion or N1, M1 Any Child-Pugh A-B Stage D: terminal 3-4 Any Any Child-Pugh C