Tests for Oral Cavity and Oropharyngeal Cancers

A doctor or dentist may find some oral cavity and oropharyngeal cancers or pre-cancers during a routine exam, but many of these cancers are found because of signs or symptoms a person is having. A dentist or doctor should examine the problem area. Then, if cancer is suspected, tests will be needed.

Exams by a doctor

Medical history and physical exam

As a first step, the doctor will ask you questions about symptoms, possible risk factors, and any other medical problems you may have.

The doctor will examine you to look for possible signs of mouth or throat cancer or pre-cancer. These could be bumps or other changed areas on your head, face or neck, or problems with the nerves of the face and mouth. The doctor will look at the entire inside of your mouth, and might feel around in it with a gloved finger. Other tests may be used to look for changed areas in your mouth or throat, or to get a better sense of what an abnormal area might be. Some of these tests are described in Can Oral Cavity and Oropharyngeal Cancers Be Found Early?

Complete head and neck exam

If there' is a reason to think you might have cancer, your doctor will refer you to a doctor who specializes in these cancers, such as an oral and maxillofacial surgeon or a head and neck surgeon (also known as an ear, nose, and throat [ENT] doctor or an otolaryngologist). This specialist will most likely do a complete head and neck exam, as well as other exams and tests.

During a complete head and neck exam, the specialist will pay special attention to the head and neck area, being sure to look and feel for any abnormal areas. This exam will include the lymph nodes in your neck, which will be felt carefully for any signs of cancer.

Because the oropharynx is part of the throat deep inside the neck, some parts are not easy to see. The doctor may use mirrors or special fiber-optic scopes to look at these areas. Both of these exams can be done in the doctor’s office. For either of them, the doctor may first spray the back of your throat with numbing medicine to help make the exam easier.

  • Indirect pharyngoscopy and laryngoscopy: To do this, the doctor uses small mirrors on long, thin handles to look at your throat, the base of your tongue, and part of the larynx (voice box).
  • Direct (flexible) pharyngoscopy and laryngoscopy: For this exam, the doctor puts a flexible fiber-optic scope (called an endoscope) in through your mouth or nose to look at areas that can’t easily be seen with mirrors, such as the region behind the nose (nasopharynx) and the larynx (voice box), or to get a clearer look at areas of change that were seen with the mirrors.


During a panendoscopy, the doctor uses different types of endoscopes passed down the mouth or nose to do a laryngoscopy, esophagoscopy, and (at times) bronchoscopy. This lets the doctor thoroughly examine the oral cavity, oropharynx, larynx (voice box), esophagus (tube leading to the stomach), and the trachea (windpipe) and bronchi (breathing passageways in the lungs).

This exam is usually done in an operating room while you are under general anesthesia (drugs that put you into a deep sleep). The doctor uses a laryngoscope to look for tumors in the throat and voice box. Other parts of your mouth, nose, and throat are examined, too. If a tumor is found that's large or seems likely to have spread, the doctor may also use an esophagoscope to look into the esophagus or a bronchoscope to look into the trachea and bronchi.

Your doctor will look at these areas through the scopes to find any tumors, see how big they are, and see how far they may have spread to nearby areas. A small piece of tissue from any tumors or other abnormal areas may be taken out (biopsied) to be looked at under a microscope to see if they contain cancer. Biopsies can be done with special tools that are used through the scopes.


In a biopsy, the doctor removes a small piece of tissue, called a sample, to be looked at under a microscope. A biopsy is the only way to know for sure that oral cavity or oropharyngeal cancer is present. A sample of tissue or cells is always needed to confirm a cancer diagnosis before treatment is started. Several types of biopsies may be used, depending on each case.

Exfoliative cytology

To do this, the doctor scrapes the changed area and smears the collected tissue onto a glass slide. The sample is then stained with a dye so the cells can be seen under the microscope. If any of the cells look abnormal, the area can then be biopsied.

The advantage of this test is that it's easy, and even only slightly abnormal-looking areas can be checked. This can lead to an earlier diagnosis and a greater chance of cure if there is cancer. But this method doesn't show all cancers. And sometimes it’s not possible to tell the difference between cancer cells and abnormal cells that aren't cancer (dysplasia), so a biopsy would still be needed.

Incisional biopsy

For this type of biopsy, the doctor cuts a small piece of tissue from the area that looks abnormal. This is the most common type of biopsy used to check changes in the mouth or throat.

The biopsy can be done either in the doctor’s office or in the operating room, depending on where the tumor is and how easy it is to get a good tissue sample. If it can be done in the doctor’s office, the area around the tumor will be numbed before the biopsy is done. If the tumor is deep inside the mouth or throat, the biopsy might be done in the operating room while you are under general anesthesia (in a deep sleep). The surgeon uses special instruments through an endoscope to take out small tissue samples.

Fine needle aspiration (FNA) biopsy

For this test, the doctor uses a very thin, hollow needle attached to a syringe to pull out (aspirate) some cells from a tumor or lump. These cells are then looked at under a microscope to see if cancer is present.

FNA biopsy is not used to sample abnormal areas in the mouth or throat, but it's sometimes used for a neck lump (mass) that can be felt or seen on a CT scan. FNA can be helpful in several situations, such as:

  • Finding the cause of a new neck mass: An FNA biopsy is sometimes used as the first test for someone with a newly found neck lump. It may show that the lump is a benign (not cancer) lymph node that has grown because of a nearby infection, such as a sinus or tooth infection. In this case, treatment of the infection is all that's needed. Or the FNA may find a benign, fluid-filled cyst that can be cured by surgery. But even when the FNA results are benign, if symptoms suggest cancer, more tests (such as pharyngoscopy and panendoscopy) are needed.
    If the FNA finds cancer, the doctor looking at the sample can usually tell what type of cancer it is. If the cells look like a squamous cell cancer, more exams will be done to search for the source of the cancer in the mouth and throat. If the FNA shows a different type of cancer, such as lymphoma or a cancer that has spread to a lymph node in the neck from another organ (like the thyroid, stomach, or lungs) more tests will be done to find it, and treatment for that type of cancer will be given.
  • Learning the extent of a known cancer: FNA is often done after oral or oropharyngeal cancer has been diagnosed to find out if the cancer has spread to lymph nodes in the neck. This information will help the doctor decide the best treatment for the cancer.
  • Seeing if cancer has come back after treatment: FNA may be used for people whose cancer has been treated by surgery and/or radiation therapy, to find out if a new neck mass in the treated area is scar tissue or cancer that has come back.

Lab tests of biopsy samples

All biopsy samples are sent to a lab to be checked under a microscope by a pathologist, a doctor who is specially trained to diagnose cancer with lab tests. The doctor can usually tell cancer cells from normal cells, as well as what type of cancer it is, by the way the cells look. In some cases, the doctor may need to coat the cells with special stains to help tell what type of cancer it is.

HPV testing

For cancers of the throat, doctors have the biopsy samples tested to see if HPV infection is present. This is a key part of staging (finding out the extent of the cancer) and is considered when making treatment decisions. This information can also help the doctor predict the probable course of the cancer, because people whose cancers are linked to HPV tend to do better than those whose cancers are not.

Imaging tests

Imaging tests use x-rays, magnetic fields, or radioactive substances to create pictures of the inside of your body. Imaging tests are not used to diagnose oral cavity or oropharyngeal cancers, but they may be done for a number of reasons both before and after a cancer diagnosis, including:

  • To help look for a tumor if one is suspected
  • To learn how far cancer may have spread
  • To find out if treatment is working
  • To look for possible signs that the cancer has come back (recurred) after treatment

Chest x-ray

After diagnosis, an x-ray of your chest may be done to see if the cancer has spread to your lungs.

Computed tomography (CT)

A CT scan uses x-rays to make detailed, cross-sectional images of your body. Unlike a regular x-ray, a CT scan creates detailed images of the soft tissues and organs in the body. It can help your doctor see the size and location of a tumor, if it's growing into nearby tissues, and if it has spread to lymph nodes in the neck. The test also may be done to look for spread of cancer to the lungs.

Magnetic resonance imaging (MRI)

Like CT scans, MRI scans show detailed images of soft tissues in the body. But MRI scans use radio waves and strong magnets instead of x-rays. Because it provides a very detailed picture, an MRI scan may be done to look for spread of the cancer in the neck. These scans can also be very useful in looking at other areas of the body, too, especially the brain and spinal cord.

Positron emission tomography (PET)

For a PET scan, a form of radioactive sugar is put into the blood. Cancer cells use sugar at a higher rate than normal cells, so they will absorb more of the radioactive sugar. After about an hour, you will be moved onto a table in the PET scanner. A special camera is used to create pictures of areas of radioactivity in your body. The picture is not finely detailed like a CT or MRI scan, but it provides helpful information about your whole body.

If you have already been diagnosed with cancer, your doctor might use this test to see if the cancer has spread to lymph nodes or other parts of the body. A PET scan can also be useful if your doctor thinks the cancer may have spread but doesn’t know where.

A PET scan is often combined with a CT scan using a machine that can perform both scans at the same time (PET/CT scan). This lets the doctor compare areas of higher radioactivity on the PET with the more detailed appearance of that area on the CT.

Barium swallow

A barium swallow can be used to see the lining of the upper part of the digestive system, especially the esophagus (the tube that connects the throat to the stomach). In this test, you drink a chalky liquid called barium which coats the walls of your throat and esophagus. A series of x-rays is taken as you swallow. Because people with oral and oropharyngeal cancers are at risk for cancer of the esophagus, your doctor may order this test to check for this cancer. It's also useful to see if the cancer is causing problems with normal swallowing.

Other tests

Other tests may be done as part of a work-up if a patient has been diagnosed with oral cavity or oropharyngeal cancer. These tests are not used to diagnose the cancer, but they may be done for other reasons, such as to see if a person is healthy enough for treatments such as surgery, radiation therapy, or chemotherapy.

Blood tests

No blood tests can diagnose cancer in the oral cavity or oropharynx. Still, your doctor may order routine blood tests to get an idea of your overall health, especially before treatment. Such tests can help diagnose malnutrition, low red blood cell counts (anemia), liver disease, and kidney disease. Blood tests may also suggest the cancer has spread to the liver or bone. When this happens, more tests are needed.

Other tests before surgery

If surgery is planned, you might also have an electrocardiogram (EKG) to make sure your heart is working well. Some people having surgery also may need tests of their lung function. These are called pulmonary function tests (PFTs).

Dental exam

If radiation therapy will be used as part of the treatment, you'll be asked to see a dentist before starting. The dentist will help with preventive dental care and may remove teeth, if needed, before radiation treatment is started.

If the cancer is in your jaw or the roof of your mouth, a dentist with special training (called a prosthodontist) might be asked to evaluate you. This dentist can make replacements for missing teeth or other structures of the oral cavity to help restore your appearance; comfort; and ability to chew, swallow, and speak after treatment. If part of the jaw or roof of the mouth (palate) will be removed with the tumor, the prosthodontist will work to ensure that the replacement artificial teeth and the remaining natural teeth fit together correctly. This can be done with dentures, other types of prostheses, or dental implants.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Huang SH, O'Sullivan B, Waldron J. The Current State of Biological and Clinical Implications of Human Papillomavirus-Related Oropharyngeal Cancer. Semin Radiat Oncol. 2018;28(1):17-26.

Koch WM, Stafford E, Bajaj G. Cancer of the Oral Cavity. Part A: General Principles and Management. In: Harrison LB, Sessions RB, Hong WK, eds. Head and Neck Cancer: A Multidisciplinary Approach. Philadelphia, Pa: Lippincott Williams and Wilkins; 2009: 250–265.

National Comprehensive Cancer Network, Clinical Practice Guidelines in Oncology (NCCN Guidelines®), Head and Neck Cancers, Version I.2018 -- February 15, 2018. Accessed at www.nccn.org/professionals/physician_gls/pdf/head-and-neck.pdf on February 26, 2018.

Quon H. Cancer of the head and neck. In: Abeloff MD, Armitage JO, Lichter AS, Niederhuber JE. Kastan MB, McKenna WG, eds. Clinical Oncology. 4th ed. Philadelphia, Pa. Elsevier; 2008: 1177–1228.


Last Medical Review: March 9, 2018 Last Revised: March 9, 2018

American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.