How ACC is Diagnosed

ACC can be diagnosed through a multitude of ways. We’d like to highlight a few of the common procedures and tests that you or your loved one might experience along this journey. 

Common Questions

What is the first step in diagnosing ACC?

Initially, a physician examination and health history will be taken for concerns in the head/neck area. A physical examination may reveal the presence of a hard fixed mass, and certain neurologic symptoms, such as facial numbness, weakness, or pain due to involvement of particular nerves. A history of the patient’s health and past illnesses and treatments will also be taken. 

Biopsies play a major role in the diagnosis of ACC. Other tests can suggest that a cancer is present, but only a biopsy can make a definite diagnosis. A biopsy involves the removal of all or a small portion of the diseased tissue for examination.

ACC tends to be a ‘mixed cell type’ with complex features and endless variations which complicate the diagnosis.  A common misdiagnosis is to identify it as it’s histomorphological relative, ‘pleomorphic adenoma’ which is a benign, non- cancerous growth which has similar features.

The pathology of ACC or salivary gland cancers can be complicated, even among experienced pathologists.  This is why it is important that the tissue be examined by a pathologist familiar with head/neck cancers or rare cancers. 

If the biopsy and other tests show that you have ACC, it’s likely that you will have more tests to help your doctor create a treatment plan.  For example, your doctor may do additional scans to figure out if the cancer has spread and how far.  This information is important to determine the stage and grade of your cancer.

Imaging tests can be used to look for cancer, find out if it has spread and determine if treatment is working. There are several different types of imaging tools each with its own advantages and disadvantages.  These tests are only part of a cancer diagnosis or treatment plan.  Additional tests such as a biopsy will determine if cancer exists as well as the stage or grade of the cancer. 

A doctor, certified technologist, or other health professional may perform your imaging test. It is a radiologist who usually interprets the images and writes the report that will be sent to your doctor(s). Because ACC requires life-long monitoring, patients should request a copy for their personal records. This also gives a patient an opportunity to read the report and ask questions. In the US, patients have the legal right to obtain their medical records once available.

Imaging tests often lead to a diagnosis, but they aren’t always perfect. 

Imaging tests are limited to finding larger groups of cancer cells and therefore unable to show just a few cancer cells. ACC has a high tendency to microscopically infiltrate surrounding nerve tissues, also called perineural invasion.  These cancerous cells are very small rather than a large cluster.  For these reasons, follow-up treatment may continue even when cancer cells can no longer be seen on an imaging test.  

On the other hand, sometimes imaging tests can show something that looks like cancer, but it’s not. Scar tissue or inflammation after surgery or radiation can often lead to further follow-up in order to rule out cancer.  Lung nodules can occur to anyone due to a lung infection, scars from a previous infection or respiratory issues.  However, because ACC has a very high risk of spreading to the lungs, doctors will continue to monitor any areas of concern watching for changes or growth.

A doctor may run tests (genome tests) if they suspect the possibility of genetic influence especially if the cancer is progressive or has spread to other parts of the body.  A genome test or tumor profile may identify genes, proteins and other factors in the tumor.  All of these factors help doctors match patients with the most effective treatment when possible. 

Specialized Imaging Tests

An MRI (Magnetic Resonance Imaging) is the most sensitive imaging technique of the head.  It is best for soft tissues such as muscles, tendons and blood vessels. The MRI uses a powerful magnetic, radio waves and a computer to produce cross-sectional images (slices) of the head, brain and other cranial structures. These slices are combined to create detailed images that are clearer and more detailed than other imaging methods.  This scan does not use ionizing radiation or emit radiation to the patient.  Before the scan, it may require an injection of contrast material to create a clearer picture.

 CT (Computerized Tomorgaph) – also known as a CAT scan – can determine the extent of the primary tumor and if invasion of other tissues have occurred. It can also be used to identify small nodules or tumors in the lung. CT images of internal organs, bones, soft tissue, and blood vessels provide greater detail than traditional x-rays.

When a patient is newly diagnosed, a PET-CT scan of the chest (lungs) and abdomen should be ordered due to the high risk of ACC metastasis. A Ct scan can detect very small nodules in the lung vs a PET or X-ray alone.

A CT scan uses an x-ray machine linked to a computer to create a film showing detailed cross-sectional images (3-dimensional images) that show any abnormalities or tumors.  Sometimes, you may receive a dye or contrast material before you have the scan. Contrast material helps make the pictures easier to read by highlighting certain areas in the head or body.

A PET (Positron Emission Tomography) measures the metabolic activity within cancer cells of the body. A small amount of radioactive sugar substance (radioactive tracer)  is injected into the patient’s body.  Since most cancer cells are highly metabolically active, they will light up bright on the PET scan.  However, because ACC normally grows slowly, low grade or smaller tumors may not be detected in the lungs.

CT scans may be used in combination with a PET scan. The combination provides more accurate diagnoses than either type of scan alone. A CT/PET scans is especially useful for detecting primary tumors of the head and neck, as well as metastases and recurrences during follow-up. 

An Endoscopy involves using a long, thin tube with a camera at the end to examine hard to reach areas of the head or body. In this case, the endoscope goes through the mouth or nose and down the throat. Different types of endoscopes are used depending on the part of the body that needs to be examined. Examples of endoscopy exams might include a bronchoscopy to exam the trachea, bronchi and lungs, a laryngoscope to exam the throat or voice box or an esophagoscope is used to evaluate various portions of the upper aerodigestive tract.

X-rays are a type of high-energy electromagnetic radiation that can pass through the body. They are used to produce images of tissues and structures in the body. They are useful for visualizing soft tissue against the air or tumors that have invaded the bone. They are best adapted for visualizing structures that absorb different amounts of radiation. Structures that absorb more x-rays will appear white (e.g. bone), whereas structures that absorb less x-rays will appear darker (e.g. lungs).

ACC patients with no history of metastasis may undergo semi-annual or annual chest x-rays to identify lung metastasis, or spread. While CT scans often give better pictures or detect smaller lung nodules, x-rays are fast, cost less and expose the patient to less radiation.


Scanxiety is a common response to having scans or tests. Whether scans are being performed for a diagnosis, to monitor treatment or to  check for a recurrence, the anxiety for many patients can be difficult. Some people feel mild (slight) worry, while others feel strong panic or distress. Patients may feel scanxiety before a scan, during a scan or while waiting for results.

Unfortunately, scans are an essential part of ACC survivorship care, so it’s important to learn how to recognize the physical and mental effects on you and those around you.  Recognizing how your body reacts can help you better manage scanxiety when it occurs. Trouble eating, sleeping, a faster heart rate, claustrophobia, mood swings, fear and more can all be symptoms of stress. Techniques to help lessen the burden may include distraction, meditation and talking to your care team.  For example, waiting for test results can be scary.  Have a plan in place for when and how to receive your results. Ask your care team when to expect the results, who will deliver them to you  and how they will be delivered (by phone, next appointment or patient portal.  The knowledge is empowering and helps manage the uncertainty while waiting for results. . 

Finally, treat yourself with compassion.  Understand that this is hard and try to ‘stay in the present’ vs. the ‘what ifs’ of the future.