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Doctors use many tests to diagnose cancer and find out if it has metastasized (spread). Some tests may also determine which treatments may be the most effective. For most types of cancer, a biopsy (see definition below) is the only way to make a definitive diagnosis of cancer. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis. Imaging tests may be used to find out whether the cancer has metastasized. Your doctor may consider these factors when choosing a diagnostic test:
- Age and medical condition
- Type of cancer suspected
- Severity of symptoms
- Previous test results
If a person has symptoms and signs of head and neck cancer, the doctor will take a complete medical history, noting all symptoms and risk factors. In addition, the following tests may be used to diagnose head and neck cancer:
Physical examination/blood and urine tests. During a physical examination, the doctor feels for any lumps on the neck, lips, gums, and cheeks. Also, the doctor will inspect the nose, mouth, throat, and tongue for abnormalities, often using a light and a mirror for a clearer view. Blood and urine tests may be performed to help diagnose cancer. Testing for viral infections, including HPV, may also be done.
Endoscopy. This test allows the doctor to see inside the body with a thin, lighted, flexible tube called an endoscope. The tube is gently inserted through the nose into the throat and down the esophagus to examine the head and neck areas. The examination has different names depending on the area of the body that is examined, such as laryngoscopy (larynx), pharyngoscopy (pharynx), or a nasopharyngoscopy (nasopharynx). When these procedures are combined, they are sometimes referred to as a panendoscopy.
Biopsy. A biopsy is the removal of a small amount of tissue for examination under a microscope. Other tests can suggest that cancer is present, but only a biopsy can make a definite diagnosis. The sample removed from the biopsy is analyzed by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease). One common type of biopsy is called a fine needle aspiration. In this procedure, cells are withdrawn using a thin needle inserted directly into the tumor. The cells are examined under a microscope for cancer cells (called cytologic examination).
Molecular testing of the tumor. Your doctor may recommend running laboratory tests on a tumor sample to identify specific genes, proteins, and other factors unique to the tumor. Results of these tests will help decide whether your treatment options include a type of treatment called targeted therapy (see Treatment).
X-ray. An x-ray is a way to create a picture of the structures inside of the body, using a small amount of radiation. A barium swallow may be required to identify abnormalities along the swallowing passage. A special type of barium swallow called a modified barium swallow may be needed to evaluate specific swallowing difficulties. A dentist may also take x-rays of the teeth and mandible and maxilla, including a panorex (panoramic view). If there are signs of cancer, the doctor may recommend a computed tomography (CT) scan (see below).
Panorex. This is a rotating, or panoramic, x-ray of the upper and lower jawbones to detect cancer or to evaluate teeth before radiation therapy or chemotherapy.
Ultrasound. An ultrasound uses sound waves to create a picture of the internal organs.
Computed tomography (CT or CAT) scan. A CT scan creates a three-dimensional picture of the inside of the body with an x-ray machine. A computer then combines these images into a detailed, cross-sectional view that shows any abnormalities or tumors. Sometimes, a contrast medium (a special dye) is injected into a patient’s vein to provide better detail.
Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body, especially images of soft tissue, such as the tonsils and base of the tongue. A contrast medium may be injected into a patient’s vein to create a clearer picture.
Bone scan. A bone scan uses a radioactive tracer to look at the inside of the bones. The tracer is injected into a patient’s vein. It collects in areas of the bone and is detected by a special camera. Healthy bone appears gray to the camera, and areas of injury, such as those caused by cancer, appear dark. This test may be done to see if cancer has spread to the bones.
Positron emission tomography (PET) scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive substance is injected into a patient’s body. This substance is absorbed mainly by organs and tissues that use the most energy. Because cancer tends to use energy actively, it absorbs more of the radioactive substance. A scanner then detects this substance to produce images of the inside of the body.
Learn more about what to expect when having common tests, procedures, and scans.
After these diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is cancer, these results also help the doctor describe the cancer; this is called staging. Learn more about the first steps to take after a diagnosis of cancer.