Nasopharyngeal cancer develops in the nasopharynx, an area in the back of the nose toward the base of skull. To understand nasopharyngeal cancer, it helps to know about the structure and function of the nasopharynx.

About the nasopharynx

The nasopharynx is the upper part of the throat (pharynx) that lies behind the nose. It is a box-like chamber about 1½ inches on each edge. It lies just above the soft part of the roof of the mouth (soft palate) and just in back of the entrance into the nasal passages.

The nasopharynx serves as a passageway for air from the nose to the throat (and eventually to the lungs).

Nasopharyngeal tumors

Several types of tumors can develop in the nasopharynx. Some of these tumors are benign (non-cancerous), while others are malignant (cancerous). It is important to discuss what type of tumor you might have with your doctor.

Benign nasopharyngeal tumors

Benign tumors of the nasopharynx are fairly rare and tend to occur in children and young adults. They include tumors or malformations of the vascular (blood-carrying) system, such as angiofibromas and hemangiomas, and benign tumors of the minor salivary glands that are found within the nasopharynx. Treatment of these tumors (if it is needed) is different from that for cancerous nasopharyngeal tumors and is not discussed further in this document. If you have one of these tumors, you and your doctor will talk about what treatments might be appropriate for you.

Malignant nasopharyngeal tumors

These tumors can invade surrounding tissues and spread to other parts of the body.

Nasopharyngeal carcinoma (NPC): This is by far the most common malignant tumor of the nasopharynx. A carcinoma is a cancer that starts in cells lining the internal and external surfaces of the body. Most of the rest of this document refers to NPC.

There are 3 types of NPC:

• keratinizing squamous cell carcinoma
• non-keratinizing carcinoma
• undifferentiated carcinoma

Each of these types is more common in some areas of the world than others. Most NPC in the United States is the keratinizing type. In Southeast Asia, where NPC is much more common, most cases are the undifferentiated type.

Although these types look different when seen under a microscope, studies have shown they start from the same cell type – the epithelial cells that cover the surface lining of the nasopharynx. The treatment is also usually the same for all types of nasopharyngeal cancer. The stage of the cancer -- how far it has grown and spread -- is often more important than its type in predicting a person's outlook (prognosis).

Many nasopharyngeal carcinomas also contain lots of immune system cells, especially lymphocytes. The term lymphoepithelioma is sometimes used to describe an NPC with many lymphocytes among the cancer cells. The presence of these cells does not usually affect the choice of treatment options. But they may be a clue to developing new treatments since they may represent the body's attempt to "reject" the tumor (for more information, see the section "What's new in nasopharyngeal cancer research and treatment?").

Other cancers in the nasopharynx: Other types of cancers can arise from the tissues that make up the nasopharynx.

Lymphomas can sometimes start in the nasopharynx. They are cancers of immune system cells called lymphocytes, cells that are normally found in the nasopharynx. These cancers are discussed in a separate American Cancer Society document, Non-Hodgkin Lymphoma.

Adenocarcinoma and adenoid cystic carcinoma are cancers that may develop in the minor salivary glands found in the nasopharynx, but they are more commonly found in the nasal or oral cavities. More information on these cancers can be found in the American Cancer Society documents, Oral Cavity and Oropharyngeal Cancer, Nasal Cavity and Paranasal Sinuses Cancer, and Salivary Gland Cancer.

Last Medical Review: 01/21/2009
Last Revised: 01/21/2009