Throat Cancer

Diagnosis

To diagnose cancer of the pharynx or larynx, the physician will first gather a medical history about the condition from the patient. Then an otorhinolaryngologist (head and neck surgeon) will examine the throat for abnormalities using a mirror or a small, flexible, fiberoptic instrument. A tissue sample (biopsy) may be taken to determine if cancer cells are present. This sample will be carefully examined in a laboratory.

Most throat cancers begin on the squamous cells that line the surface of the throat. As a result, when physicians diagnose the condition early, treatment is often successful. To determine if the cancer has spread beyond the surface of the throat, the physician may order the following imaging procedures:

• X-rays produce one-dimensional images of the mouth, head and chest.
• Computer tomography (CT) involves the use of thin X-ray beams to create images of internal organs in two-dimensional slices.
• Magnetic resonance imaging (MRI) scans use magnetic field and radio waves to create images that can be viewed from any direction or plane to determine the extent of the cancer and whether the lymph nodes are involved.
• Ultrasound involves the use of a wandlike device (transducer) to combine high-frequency sound waves and computer processing to show physicians the shape and texture of the tumor.
• Positron emission tomography (PET) scan is a type of radionuclide scan in which a small amount of a radioactive tracer is injected into the body. Tissues that use more energy, including tumors, absorb greater amounts of tracer showing tumors on the scan.

Tumor Staging

Physicians classify cancers of the larynx and pharynx into "stages" according to the spread of the disease. The chance for recovery depends on where the cancer starts, whether it has spread to other tissues and the patient's general health. Staging helps physicians plan treatment. The following general stages are used for cancers of the larynx and pharynx:

Stage I — The cancer is small and found only in the area where it started. It has not spread to lymph nodes or to other parts of the body. If it is in the supraglottis or the glottis of the larynx, the vocal cords can move normally.

Stage II — The cancer remains confined to the larynx or pharynx and has not spread to nearby lymph nodes. The exact definition of the stage depends on where the cancer started. These cancers are larger and involve more areas than Stage I cancers.

Stage III — One of these two conditions exists:

• The cancer is larger than stage II and involves more structures. If the cancer is in the larynx, the vocal cords cannot move normally, or the cancer has spread to tissues next to the larynx.
• The cancer has spread to one lymph node on the same side of the neck as the cancer, and the lymph node measures no more than 3 centimeters (just over 1 inch).

Stage IV — Any of the following may be true:

• The cancer is very large and involves several structures extensively. If the cancer started in the larynx, it has spread to tissues around the larynx, such as the pharynx or the tissues in the neck. The lymph nodes in the area may or may not contain cancer.
• The cancer has spread to more than one lymph node on the same side of the neck as the cancer, to lymph nodes on one or both sides of the neck, or to any lymph node that measures more than 6 centimeters (over 2 inches).
• The cancer has spread to other parts of the body.

About the Pharynx and Larynx

The pharynx (throat) performs many functions including delivery of food and drink to the stomach, of sounds from the vocal cords to the mouth, and of air from the nose to the lungs. It is a muscular tube that starts behind the nose and stretches about five inches down through the neck to the esophagus (the tube that carries food to the stomach). The mouth and the larynx, located lower down, open into the front of the pharynx.

The larynx (voice box or Adam's apple) forms a short, triangular passageway in front of the pharynx. It connects to the trachea (the tube leading to the lungs). The larynx contains vocal cords, which vibrate when air passes over them and produce vocal sounds.