Cancer stage indicates how large the tumor is and whether it has spread. The TNM classification system describes the stage of cancer in the body. According to this system:

T; refers to the size of the tumor at its origin,

N; for head and neck tumors, refers to the size and condition of the tumor that has metastasized (spread) to the lymph nodes in the neck,

M; indicates the presence of metastasis in distant organs, often via the bloodstream, beyond the neck.

In summary, the stage of cancer depends on the following factors:

How much the cancer has grown in the local tissues
Whether it has spread to nearby lymph nodes
Whether it has spread to another part of the body