How Are Nasal Cavity and Paranasal Sinus Cancers Diagnosed?

Nasal cavity and paranasal sinus cancers are usually found because of signs or symptoms a person is having. The doctor will take a history and examine the patient. If cancer is suspected, the patient will be referred to a specialist and tests will be done to confirm the diagnosis.

Medical history and physical exam

When your doctor takes your medical history, you will be asked a series of questions about your symptoms and possible risk factors. A physical exam will provide other information about signs of nasal cavity and paranasal sinus cancer and other health problems.

During your physical exam, your doctor will pay special attention to the areas of your nose and sinuses that are causing symptoms. He or she will also pay attention to areas of numbness or pain, swelling and firmness in areas of the face or lymph nodes in the neck, changes in the symmetry of your eyes and face, visual changes, and any other problems you may be having.

Your doctor may also examine the nasal cavity with a headlight or even look inside your nose with a special instrument called a nasal endoscope (a thin tube designed to allow the doctor to see into the nasal passages).

If your doctor suspects you might have cancer of the nasal cavity or paranasal sinuses, you will be referred to an otolaryngologist (a doctor who specializes in diseases of the ear, nose, and throat; also known as an ENT doctor), who will more thoroughly examine your nasal passages and the rest of your head and neck area. This might include an exam of your throat, which can be done with small mirrors or with a fiber-optic scope – a thin, flexible, lighted tube that is passed down through the mouth or nose.

Imaging tests

Imaging tests use x-rays, magnetic fields, or other means to create pictures of the inside of your body. Imaging tests are not used to diagnose nasal cavity or paranasal sinus 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 help determine if treatment has been effective
  • To look for possible signs of cancer recurrence after treatment

X-rays of the sinuses

X-rays can show if the sinuses are not filled by air as they should be. This would suggest that something is wrong, but it may not be a tumor. Most of the time, an abnormal-looking sinus x-ray means there is an infection. If treatment for infection doesn’t work, then other more specialized x-ray tests may be done. Sinus x-rays are not done often any more, as many doctors prefer to order a computed tomography (CT) scan instead. A CT scan provides much more detail about the anatomy of the sinuses.

Computed tomography (CT) scan

The CT scan uses x-rays to produce detailed cross-sectional images of your body. This test is very useful in identifying cancers of the nasal cavity and paranasal sinuses. It may also be done to see if the cancer has spread to the lungs.

A CT scanner has been described as a large donut, with a narrow table in the middle opening. You will need to lie still on the table while the scan is being done. CT scans take longer than regular x-rays, and you might feel a bit confined by the ring while the pictures are being taken.

Instead of taking one picture like a standard x-ray, a CT scanner takes many pictures of the part of your body being studied as it rotates around you. A computer then combines these pictures into an image of a slice of your body. Unlike a regular x-ray, a CT scan creates detailed images of the soft tissues and organs in the body.

Often after the first set of pictures is taken, you may receive an injection of a “dye” or radiocontrast agent into an intravenous (IV) line. This dye helps to better outline structures in your body. A second set of pictures is then taken. Some people are allergic to the dye and get hives, a flushed feeling, or, rarely, more serious reactions like trouble breathing and low blood pressure. Be sure to tell your doctor if you have any allergies or have ever had a reaction to any contrast material used for x-rays.

Magnetic resonance imaging (MRI) scan

MRI scans use radio waves and strong magnets instead of x-rays. The energy from the radio waves is absorbed and then released in a pattern formed by the type of tissue and by certain diseases. A computer translates the pattern of radio waves given off by the tissues into a very detailed image of parts of the body. A contrast material might be injected, but this is different from the one used for CT scans, so being allergic to one doesn’t mean you are allergic to the other.

MRI scans are very helpful in looking at cancers of the nasal cavities and paranasal sinuses. They are better than CT scans in distinguishing fluid from tumor, and sometimes they can help the doctor tell the difference between a benign tumor and a cancerous one.

MRI scans are a little more uncomfortable than CT scans. First, they take longer – often up to an hour. Second, you have to lie inside a narrow tube, which is confining and can upset people with claustrophobia (a fear of enclosed spaces). Special, more open MRI machines can sometimes help with this if needed, although the images may not be as sharp in some cases. MRI machines make buzzing and clicking noises that you may find disturbing. Some centers provide earplugs to help block this noise out.

Both CT and MRI help identify cancers of the nasal cavities and paranasal sinuses and their characteristics. The CT scan can tell if the cancer is growing into bone, but the MRI is better at evaluating the kind and size of the cancer. Both can tell if it has spread to lymph nodes in the neck.

Chest x-ray

If you have been diagnosed with nasal cavity or paranasal sinus cancer, this test might be done to find out if the cancer has spread to your lungs, which is the most common site of spread other than lymph nodes.


A biopsy is a procedure in which a doctor removes a sample of tissue to be looked at under a microscope. It is the only way to confirm the diagnosis of nasal cavity or paranasal sinus cancer. If cancer is found, the biopsy can also help the doctor tell what type of cancer it is and how aggressive it is. This is important to help plan the most effective treatment.

Often, biopsies are done in the doctor’s office or clinic. If the tumor is in a hard-to-reach area, the biopsy will be done in the operating room. Several types of biopsies can be used to diagnose nasal cavity or paranasal sinus cancer.

Fine needle aspiration (FNA) biopsy

In this type of biopsy, the doctor places a thin, hollow needle directly into a tumor or lymph node to take out cells and a few drops of fluid. The doctor may repeat this procedure 2 or 3 times during the same appointment to take several samples. The cells can then be viewed under a microscope to see if they look cancerous or benign.

This type of biopsy is often used in patients with enlarged lymph nodes in the neck. In these patients, fine needle biopsy can be useful in deciding if the lymph node swelling is from cancer or if it is a response to an infection. If someone who has already been diagnosed with nasal cavity or paranasal sinus cancer has enlarged neck lymph nodes, a fine needle biopsy can help determine if the lymph node swelling is caused by the spread of cancer.

Incisional and excisional biopsies

These types of biopsies remove more of the tumor using a minor surgical procedure. They are the more common types of biopsies for nasal and paranasal sinus tumors. Biopsies of tumors in the nose may be done using special instruments placed into the nose. Biopsies of tumors that are deeper within the skull may require a more involved procedure (see below).

For an incisional biopsy, the surgeon cuts out a small piece of the tumor. For an excisional biopsy, the entire tumor is removed. In either case, the biopsy sample is then sent to the lab for analysis.

Endoscopic versus open biopsy

For tumors deeper within the skull, how the biopsy is obtained depends on where it is and how large it is.

Endoscopic biopsy: Some tumors that are deep in the nasal passages may be reached using an endoscope – a thin, flexible lighted tube. Long, thin surgical instruments can be passed down the endoscope to get a biopsy sample.

Open (surgical) biopsy: For tumors inside the sinuses, it may be necessary to cut through the skin next to the nose and through the underlying bones to reach them. These operations are discussed in greater detail in the section Surgery for Nasal Cavity and Paranasal Sinus Cancer.

Anesthesia for biopsies

The type of anesthesia used depends on which biopsy method is used.

Local anesthesia (numbing medicine) is often used for an incisional biopsy or needle biopsy. The anesthetic can be injected into the skin and nearby tissues or even applied directly on the inside of the nose to numb the area for the biopsy.

Sedation (where you are made very drowsy) or general anesthesia (where you are asleep) may be required for endoscopic biopsies. General anesthesia is needed for procedures that cut through the sinus bones.

See Testing Biopsy and Cytology Specimens for Cancer to learn more about different types of biopsies, how the tissue is used in the lab for disease diagnosis, and what the results will tell you.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master’s-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: April 22, 2014 Last Revised: August 8, 2016

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