After nasopharyngeal cancer has been diagnosed, tests are done to find out if cancer cells have spread within the nasopharynx or to other parts of the body.
The process used to find out whether cancer has spread within the nasopharynx or to other parts of the body is called staging. The information gathered from the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment. The results of the tests used to diagnose nasopharyngeal cancer are often also used to stage the disease. (See the General Information section.)
There are three ways that cancer spreads in the body.
The three ways that cancer spreads in the body are:
- Through tissue. Cancer invades the surrounding normal tissue.
- Through the lymph system. Cancer invades the lymph system and travels through the lymph vessels to other places in the body.
- Through the blood. Cancer invades the veins and capillaries and travels through the blood to other places in the body.
When cancer cells break away from the primary (original) tumor and travel through the lymph or blood to other places in the body, another (secondary) tumor may form. This process is called metastasis. The secondary (metastatic) tumor is the same type of cancer as the primary tumor. For example, if breast cancer spreads to the bones, the cancer cells in the bones are actually breast cancer cells. The disease is metastatic breast cancer, not bone cancer.
The following stages are used for nasopharyngeal cancer:
Stage 0 (Carcinoma in Situ)
In stage 0, abnormal cells are found in the lining of the nasopharynx. These abnormal cells may become cancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.
In stage I, cancer has formed and the cancer:
- is found in the nasopharynx only; or
- has spread from the nasopharynx to the oropharynx and/or to the nasal cavity.
The oropharynx is the middle part of the throat and includes the soft palate, the base of the tongue, and the tonsils.