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 the person has noticed a sign or symptom and brought it to their attention. Then, if cancer is suspected, other tests will be needed.

Tests to find oral cavity or oropharyngeal cancer

The doctor will ask you about symptoms, possible risk factors, and any other medical problems you may have.

The doctor will 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 might be used to look for abnormal areas in your mouth or throat. 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 specialist. These specialists are oral and maxillofacial surgeons or head and neck surgeons. They are also known as ear, nose, and throat (ENT) doctors or otolaryngologists. The specialist will most likely do a complete head and neck exam, as well as order other exams and tests.

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 swelling.

Because the oropharynx is 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. The doctor may first spray the back of your throat with numbing medicine to help make the exam easier.

• Indirect pharyngoscopy and laryngoscopy: Small mirrors on long, thin handles are used to look at your throat, the base of your tongue, and part of the larynx (voice box).
• Direct (flexible) pharyngoscopy and laryngoscopy: A flexible fiber-optic scope (called an endoscope) is put in through your mouth or nose to look at areas that can’t easily be seen with mirrors. It can get a clearer look at areas of change that were seen with the mirrors and also the part behind the nose (nasopharynx) and the larynx (voice box).

Panendoscopy

Since tobacco and alcohol use are risk factors for oral cavity and oropharyngeal cancers, as well as cancers of the esophagus and lung, there is a chance (up to 10%) of finding more than one cancer at the same time. To make sure there are no other cancers in the esophagus or lung, a panendoscopy might be done. This procedure is also helpful if it is unclear where the cancer started or if the lymph nodes in the bottom part of the neck seem abnormal.

During a panendoscopy, the doctor uses different types of endoscopes passed down the mouth or nose to do a laryngoscopy/pharyngoscopy, 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 passages in the lungs).

This exam is usually done in an operating room while you are asleep under general anesthesia. 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. The doctor might also use an esophagoscope to look into the esophagus or a bronchoscope to look into the trachea (windpipe) 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 might have spread to nearby areas. A small piece of tissue from any tumors or other abnormal areas might be taken out to be looked at closely (biopsied) to see if they contain cancer. Biopsies can be done with special tools that are used through the scopes.

Biopsy

In a biopsy, the doctor removes a small piece of tissue or a sample of cells, so it can be looked at closely in the lab for cancer cells. 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

For exfoliative cytology, 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 clearly. If any of the cells look abnormal, the area can then be biopsied.

The advantage of this test is that it's easy to do and causes very little pain. This can lead to an earlier diagnosis and a greater chance of treatment being successful if cancer is found. 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 (such as dysplasia), so a different type of biopsy would still be needed.

Incisional biopsy

For an incisional biopsy, a small piece of tissue is cut 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 in a deep sleep under general anesthesia.

Fine needle aspiration (FNA) biopsy

For a fine needle aspiration (FNA) biopsy, a very thin, hollow needle attached to a syringe pulls out (aspirates) some cells from a tumor or lump. These cells are then looked at closely in the lab 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 some 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 lump in the neck. 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 other symptoms suggest cancer, more tests (such as pharyngoscopy and panendoscopy) are needed.

If the FNA sample has cancer cells, the doctor looking at the biopsy 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 or lungs) more tests will be done to find it, and treatment for that type of cancer will be given.

Learning how far a diagnosed cancer has spread: FNA also might be 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 might 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 closely by a pathologist, a doctor who is specially trained to diagnose cancer from a biopsy. 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 test the cells with special stains to help find out what type of cancer it is.

HPV (p16) testing

For cancers of the throat, the biopsy samples are often tested (for the p16 protein) to see if HPV infection is present. This is a key part of staging (finding out if and how much the cancer has spread) and is considered when making treatment decisions for oropharyngeal cancer. 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 are not used to diagnose oral cavity or oropharyngeal cancers, but they may be done for a number of reasons before and after a cancer diagnosis, including:

• To look at a suspicious area that might be cancer
• To learn how far cancer might have spread
• To help find out if treatment is working
• To look for signs that the cancer has come back (recurred) after treatment

Chest x-ray

An x-ray of your chest might be done after oral cavity or oropharyngeal cancer has been diagnosed to see if the cancer has spread to the lungs. More often though, a CT scan or PET/CT scan of the lungs is done since they tend to give more detailed pictures.

Computed tomography (CT or CAT scan)

A CT scan uses x-rays to make detailed, cross-sectional images of your body. It can help your doctor see the size and location of a tumor, if it's growing into nearby tissues, if it has spread to lymph nodes in the neck, or to the lungs or other distant organs.

CT-guided needle biopsy: If a lung biopsy is needed to check for cancer spread, this test can also be used to guide a biopsy needle into the mass (lump) to get a tissue sample to check for cancer.

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. A contrast material called gadolinium may be injected into a vein before the scan to get clear pictures. An MRI scan may be done for oral cavity cancer if there are a lot of dental fillings that might distort the CT pictures or to look closely if the cancer is growing into the bone marrow.

Positron emission tomography (PET)

For a PET scan, a slightly radioactive form of sugar (known as FDG) is injected into the blood and collects mainly in cancer cells.

PET/CT scan: Often a PET scan is combined with a CT scan using a special machine that can do both scans at the same time. This lets the doctor compare areas of higher radioactivity on the PET with the more detailed picture on the CT scan.

PET/CT scans can be useful:

• If your doctor thinks the cancer might have spread but doesn’t know where. They can show spread of cancer to the liver, bones, and some other organs.
• In follow up of patients after oral cavity or oropharyngeal cancer treatment.

Bone scan

For a bone scan, a small amount of low-level radioactive material is injected into the blood and collects mainly in abnormal areas of bone. A bone scan can help show if a cancer has spread to the bones. But this test isn’t needed very often because PET scans can usually show if cancer has spread to the bones.

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. Your doctor may order this test because people with oral and oropharyngeal cancers are at risk for cancer of the esophagus. It's also useful to see if the cancer is causing problems with swallowing.

Ultrasound

An ultrasound uses sound waves and their echoes to create images of the inside of the body. A small microphone-like instrument called a transducer gives off sound waves and picks up the echoes as they bounce off organs. The echoes are converted by a computer into an image on a screen.

Neck ultrasound: For this exam, a technician moves the transducer along the skin over your neck. This type of ultrasound can be used to look for lymph nodes in the neck to see if they are swollen or if they look abnormal inside which could be signs of cancer. The ultrasound can help guide a needle into the abnormal lymph node for an FNA biopsy. It might also be used after treatment to look for signs of cancer coming back (recurrence).

Quit smoking before oral cavity or oropharyngeal treatment

It is very important to quit smoking before any treatment for oral cavity and oropharyngeal cancer. If you used to smoke cigarettes before being diagnosed, it is important to not start during treatment. Smoking during treatment can cause:

• Poor wound healing, especially after surgery
• More side effects from chemo
• Radiation to not work as well
• A higher chance of getting an infection
• Longer stays in the hospital
• A greater chance of dying. 

Pre-treatment tests for oral cavity or oropharyngeal cancer

Other tests might 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 test 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 poor nutrition and low blood cell counts. A complete blood count (CBC) looks at whether your blood has normal amounts of different types of blood cells. For example, it can show if you are anemic (have a low number of red blood cells). Blood chemistry tests can help determine how well your liver or kidneys are working. 

Function 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 breathing tests, called pulmonary (lung) function tests.

Dental exam before radiation treatment

If radiation therapy will be part of the treatment, you'll be asked to see a dentist before starting. The dentist will help with routine dental care and may remove any bad teeth, if needed, before radiation treatment is started. Radiation can damage the saliva (spit) glands and cause dry mouth. This can increase the chance of cavities, infection, and breakdown of the jawbone.

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.

Hearing tests

Cisplatin, the main chemotherapy drug used in treating oral cavity and oropharyngeal cancer can cause hearing loss. Your care team will most likely have your hearing checked (with an audiogram) before starting treatment to compare to later if you happen to have hearing problems from chemo.  

Nutrition and speech tests

Often, you will have a nutritionist who will evaluate your nutrition status before, during, and after your treatment to try and keep your weight and protein stores as normal as possible. You might also visit a speech therapist who will test your ability to swallow and speak. They might give you exercises to do during treatment to help strengthen the muscles in the head and neck area so you can eat and talk easily after treatment.