For hepatocellular carcinoma: Stage IV includes: IVA: (Any T, N1, M0); IVB: (Any T, Any N, M1). N1: Regional lymph node metastasis. M0: No distant metastasis. M1: Distant metastasis. For intrahepatic cholangiocarcinoma: Stage IVA includes: (T4, N0, M0); (Any T, N1, M0). T4: Tumor with periductal invasion. N0: No regional lymph node metastasis. N1: Regional lymph node metastasis. M0: No distant metastasis. Stage IVB includes: Any T, Any N, M1. M1: Distant metastasis. (from AJCC 7th Ed.) [from NCI]