ON THIS PAGE: You will learn about how doctors describe a tumor’s growth or spread. This is called the stage. To see other pages, use the menu.
Staging is a way of describing where a cancerous tumor is located, if or where it has spread, and whether it is affecting other parts of the body. Doctors use diagnostic tests to find out 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, which is the chance of recovery. There are different stage descriptions for different types of cancer.
TNM staging system
There is no standard staging system used for AdCC, but the staging system for a major salivary gland tumor  is often used, which is based on the TNM system. Doctors use the results from diagnostic tests and scans to answer these questions:
Tumor (T): How large is the primary tumor? Where is it located?
Node (N): Has the tumor spread to the lymph nodes? If so, where and how many?
Metastasis (M): Has the cancer metastasized to other parts of the body? If so, where and how much?
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.
Here are more details on each part of the TNM system:
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: The primary tumor cannot be evaluated.
T0: No evidence of a tumor is found.
T1: The tumor is small, 2 centimeters (cm) at its widest dimension. It is also noninvasive, which means it has not grown outside the area where it began.
T2: The tumor is larger, between 2 cm and 4 cm, but noninvasive.
T3: The tumor is larger than 4 cm, but not larger than 6 cm, and 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 has invaded the skin, jawbone, ear canal, and/or facial nerve.
T4b: The tumor has invaded the skull base and/or the nearby bones and/or encases the arteries.
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: The neck has undergone an intervention that prevents the evaluation of lymph nodes.
N0: There is no evidence of cancer in the regional nodes.
N1: The 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: The 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: The 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: The cancer has spread to more than one lymph node on either side of the body, and no tumor measures larger than 6 cm.
N3: The cancer found in the lymph nodes is larger than 6 cm.
The "M" in the TNM system describes cancer that has spread to other parts of the body, called distant metastatsis.
MX: Distant metastasis cannot be evaluated.
M0: The cancer has not spread to other parts of the body.
M1: The cancer 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: This stage describes a noninvasive tumor (T1 or T2) with no spread to lymph nodes (N0) and no distant metastasis (M0).
Stage II: This stage describes an invasive tumor (T3) with no spread to lymph nodes (N0) or distant metastasis (M0).
Stage III: This stage describes a smaller tumor (T1 or T2) that has spread to regional lymph nodes (N1) but shows no sign of metastasis (M0).
Stage IVA: This stage describes any invasive tumor (T4a) that either has no lymph node involvement (N0) or has spread to only a single, same-sided lymph node (N1), but with no metastasis (M0). It is also used to describe a T3 tumor with one-sided nodal involvement (N1) but no metastasis (M0), or any tumor (any T) with extensive nodal involvement (N2) but no metastasis (M0).
Stage IVB: This stage describes any cancer (any T) with more extensive spread to lymph nodes (N2 or N3) and no metastasis (M0).
Stage IVC: This stage describes any cancer (any T, any N) with distant metastasis (M1).
Recurrent: Recurrent cancer is cancer has come back after treatment. If the cancer does return, there will be another round of tests to learn about the extent of the recurrence. These tests and scans are often similar to those done at the time of the original diagnosis. 
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, Seventh Edition published by Springer-Verlag New York, www.cancerstaging.net .
Information about the cancer’s stage will help the doctor recommend a specific treatment plan. The next section in this guide is Treatment Options.  Or, use the menu to choose another section to continue reading this guide.