The principles for staging liver cancer have not reached to an agreement in international society, for example, U.S.A adopt TNM staging standards in which T stands for the sizes of tumor, N for metastasis situation, M for whether cancer cells have transferred to other organ, while for the detailed subdivisions in the T, N, M, see details in the followings:

T1 means that the diameter of tumor is below 2cm, without blood or lymph metastasis.

T2 means that although the diameter of tumor is below 2cm, while tumor has invaded to adjacent blood vessel; or there are two cancer lumps whose diameters are below 2cm, and no invasion has occurred to blood vessel; or the diameter of tumor is 2cm or above, but no invasion has occurred to blood vessel.

T3 means that the diameter of tumor has reached to 2cm or above and the tumor has invaded to blood vessels; or there are several lumps whose diameters have not reached 2 cm, but these lumps have invaded into blood vessels; or there are one or more tumors whose diameter have exceeded 2cm.

T4 means that both lobes of liver have got tumors or tumor has invaded to portal vein of liver.
N0 means that no lymph node metastasis has occurred, while N1 means that lymph node metastasis has occurred.
M0 means that no distant metastasis has occurred, while M1 means that the contrary.

Stage I: T1N0MO patients belong to Stage I, and are early stage patients.
Stage II: T2N0M0 patients belong to Stage II.
Stage III: T1N1M0, T2N1M0, T3N1MO patients belong to Stage III.
Stage IVa: T4M0 patients have not occurred distant metastasis.
Stage IVb: T4M1 patients have occurred distant metastasis.