Staging

Staging is a way of describing a cancer, such as where it is located, if or where it has spread, and if it is affecting the functions of other organs in the body. Doctors use diagnostic tests to determine the cancer’s stage, so staging may not be complete until all of the tests are finished. Knowing the stage helps the doctor to decide what kind of treatment is best and can help predict a patient’s prognosis (chance of recovery). There are different stage descriptions for different types of cancer.

There is no uniform staging system used for AdCC, but often the staging system for a major salivary gland tumor is used.

One tool that doctors use to describe the stage is the TNM system. This system uses three criteria to judge the stage of the cancer: the size of the tumor itself, whether or not the tumor has spread to the lymph nodes around the tumor, and if the tumor has spread to other parts of the body. The results are combined to determine the stage of cancer for each person. There are five stages: stage 0 (zero) and stages I through IV (one through four). The stage provides a common way of describing the cancer so doctors can work together to plan the best treatments.

TNM is an abbreviation for tumor (T), node (N), and metastasis (M). Doctors look at these three factors to determine the stage of cancer:

• How large is the primary tumor and where is it located? (Tumor, T)
  
  
• Has the tumor spread to the lymph nodes? (Node, N)
  
  
• Has the cancer metastasized to other parts of the body? (Metastasis, M)

Tumor. Using the TNM system, the "T" plus a letter or number (0 to 4) is used to describe the size and location of the tumor. Some stages are divided into smaller groups that help describe the tumor in even more detail. Specific tumor stage information is listed below.

TX: Indicates the primary tumor cannot be evaluated.

T0: No evidence of a tumor is found.

T1: Describes a small noninvasive tumor that is 2 centimeters (cm) at its greatest dimension.

T2: Describes a larger noninvasive tumor, between 2 cm to 4 cm.

T3: Describes a tumor that is larger than 4 cm, but not larger than 6 cm, that has spread beyond the salivary gland. However, the tumor does not affect the seventh nerve, which is the facial nerve that controls such expressions as smiles or frowns.

T4a: The tumor invades the skin, jawbone, ear canal, and/or facial nerve.

T4b: The tumor invades the skull base and/or the nearby bones and/or encases the arteries.

Node. The “N” in the TNM staging system is for lymph nodes, the tiny, bean-shaped organs that help fight infection. For AdCC, lymph nodes near the head and neck are called regional lymph nodes. Lymph nodes in other parts of the body are called distant lymph nodes.

NX: Indicates the regional lymph nodes cannot be evaluated.

N0: There is no evidence of cancer in the regional nodes.

N1: Indicates that cancer has spread to a single node on the same side as the primary tumor and the cancer found in the node is 3 cm or smaller.

N2: Describes any of these conditions:

N2a: Cancer has spread to a single lymph node on the same side as the primary tumor, and is larger than 3 cm, but not larger than 6 cm.

N2b: Cancer has spread to more than one lymph node on the same side as the primary tumor, and no tumor measures larger than 6 cm.

N2c: Cancer has spread to more than one lymph node on either side of the body, and no tumor measures larger than 6 cm.

N3: Cancer found in lymph nodes is larger than 6 cm.

Distant metastasis. The "M" in the TNM system describes cancer that has spread to other parts of the body.

MX: Indicates distant metastasis cannot be evaluated.

M0: Indicates the cancer has not spread to other parts of the body.

M1: Describes cancer that has spread to other parts of the body.

Cancer stage grouping

Doctors assign the stage of the cancer by combining the T, N, and M classifications.

Stage I: Describes a noninvasive tumor (T1, T2) with no spread to lymph nodes (N0) and no distant metastasis (M0).

Stage II: Describes an invasive tumor (T3) with no spread to lymph nodes (N0) or distant metastasis (M0).

Stage III: Describes a smaller tumor (T1, T2) that has spread to regional lymph nodes (N1), but have no sign of metastasis (M0).

Stage IVA: Describes any invasive tumor (T4a) with either no lymph node involvement (N0) or spread to only a single, same-sided lymph node (N1), but no metastasis (M0). It is also used for a T3 tumor with one-sided nodal involvement (N1), but no metastasis (M0), or any tumor (T) with extensive nodal involvement (N2).

Stage IVB: Describes any cancer (any T) with more extensive spread to lymph nodes (N2, N3) and no metastasis (M0).

Stage IVC: Describes any cancer (any T, any N) with distant metastasis (M1).

Recurrent: Recurrent cancer is cancer that comes back after treatment.

Used with permission of the American Joint Committee on Cancer (AJCC), Chicago, Illinois. The original source for this material is the AJCC Cancer Staging Manual, Sixth Edition (2002) published by Springer-Verlag New York, www.springer-ny.com.