Head and neck cancer is a general description that is used for a number of different types of malignant tumors that occur in the mouth, throat, sinuses, nasal spaces, the larynx, salivary glands, and the cervical lymph nodes. Tumors of the brain or thyroid are usually not considered to be a part of this general category of tumors. Head and neck cancers may spread to lymph nodes in the neck, and to other parts of the body.
The American Cancer Society estimates that there will be 59,000 cases of head and neck cancer diagnosed in the United States each year. Although this represents only about 5% of all cancers diagnosed, it is particularly devastating because of the functional problems that may result from treatment. Estimates indicate that there are more than 500,000 survivors of oral and head and neck cancers living in the United States today.
Source: American Cancer Society Cancer Facts & Figures 2015.
Atlanta: American Cancer Society; 2015
Early cancers of the head and neck may be found by a number of symptoms, including:
- Sore on the lip or in the mouth that does not heal
- Lump on the lip or in the mouth or throat
- Unusual bleeding, pain, or numbness in the mouth
- Sore throat or a feeling that something is caught in the throat
- Change in the voice
While these symptoms may often be caused by other less serious problems, it is important to see a doctor about any symptoms like these.
Dentists screen for head and neck cancers by observation of abnormal cells in the mouth and physicians by physical examination of the head and neck area. Quite often physicians first detect the cancer as lymph node metastases. In these cases anatomic imaging and biopsies are usually performed to search for the primary tumor. PET/CT imaging can help physicians locate some primary lesions not identified by other methods, and can help determine if and how far the cancer has spread.
The earlier cancer is diagnosed, the sooner treatment can begin.
Treatment for head and neck cancer may involve surgery, radiation, and chemotherapy, depending on the stage of the cancer when it is first diagnosed. Accurate staging is very important in patients with head and neck cancer as distant metastatic disease or the presence of a secondary primary tumor can render the patient inoperable.
Chemotherapy and radiation therapy can be very effective in some head and neck cancers, and a rapid assessment of treatment response by PET/CT imaging can help physicians determine if these treatments are working. If chemotherapy and radiation therapy are effective then patients may be able to avoid disfiguring and expensive surgery.
A PET/CT scan can show where tumor cells are growing, which helps the doctor determine the best course of treatment.
Aggressive cancer treatments may affect normal cells as well as cancer cells, giving patients additional symptoms in the follow-up period. This makes it especially important to know if these aggressive treatments are being effective. Early in the course of treatment PET/CT imaging can be used to help the physician determine if the tumor glucose metabolism is reduced and if the treatment is working.
After a patient’s treatment the physician will closely monitor the patient’s progress and look for any signs that the cancer may have returned. Early detection of any recurrent disease after treatment is important because salvage therapy can be quite successful for managing residual or recurrent tumor if it is identified at an early stage.
The anatomy of the head and neck area is complex, especially after surgery, and conventional anatomic imaging procedures are much less useful because of the distortion of anatomy caused by treatment. An abnormality may be present after treatment, which would be visible on a CT scan, but anatomic imaging cannot determine if the tumor has been successfully treated or if residual cancer remains within the scar tissue.
PET/CT imaging has a particularly important role, to help detect suspected residual or recurrent disease.
PET/CT is a noninvasive test that physicians utilize to stage the body for the presence or absence of active tumor, localize the tumor, assess the tumor response to treatment and detect recurrence in treated lesions.
PET/CT Utilization for Head and Neck Cancer
- Locating some primary lesions not identified by conventional imaging
- Detecting tumor metastases in normal sized lymph nodes
- Staging for distant metastases or second primary lesion
- Assessing treatment response and evaluating after surgery or radiation treatment
- Detecting recurrent disease
Source: Atlas of Clinical Positron Emission Tomography by Sallie F. Barrington, Michael N. Maisey and Richard R. Wahl. Oxford University Press, Inc. New York, NY.