Staging

Staging describes the extent of a cancer, especially whether the disease has spread from the original site to other parts of the body. Staging is important in cancer diagnosis because it assists the physician with determining the progression of a disease in order to choose an appropriate method of treatment and to accurately assess a prognosis.

The most widely used system in the United States for staging cancer is called the TNM System. It describes the extent of the primary tumor (T stage), the absence or presence of spread to nearby lymph nodes (N stage) and the absence or presence of distant spread, or metastasis (M stage).

The TNM System involves using the letters T, N and M to assess tumors by:

• the size of the primary tumor (T);
• the degree to which regional lymph nodes (N) are involved; and
• the absence or presence of distant metastases (M).

Once the T, N and M are determined, a "stage" of I, II, III or IV is assigned:

• Stage I cancers are small, localized and usually curable.
• Stage II and III cancers typically are locally advanced and/or have spread to local lymph nodes.
• Stage IV cancers usually are metastatic (have spread to distant parts of the body) and generally are considered inoperable.

Staging head and neck cancers can be difficult. Although the nodal and metastasis staging systems stay the same regardless of the location of the cancer in the head and neck, the tumor staging systems are different. The nodal and metastasis staging systems are outlined below.

These tables show the combination of tumor stage and nodal/metastasis stages in approximating the overall stage of a patient, wherever the primary tumor is located.

Nodes

Metastasis

General Summary of TNM System