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Overvew of Diagnostic Tests

There are many diagnostic tests that can be performed to properly diagnose a parotid tumor or parotid gland disease. The type of diagnostic test that is used to diagnose your condition will depend on your personal circumstances and the preference of your physician.

It can be confusing to patients why certain diagnostic tests are used versus other tests. If you are confused about diagnostic tests that have been ordered, it is reasonable for a patient to ask a physician to explain why that test is being ordered and to explain what information they hope to gain from the test.

For more detailed information about each type of diagnostic test, refer to the other tabs in this section.

Why Would Additional Diagnostic Tests Be Ordered?

There may be times when a physician requests additional testing. It is hard for patients not to worry and assume that means that the physician suspects the patient has cancer, and/or there is some problem that the patient is not being told about.

Please do not panic if additional tests are ordered because there can be many reasons why a physician will order additional tests.

Often times, a physician will order more tests simply because they need additional information. They may need more information due to poor image quality of previous diagnostic tests or because the reports explaining the findings of those tests were unclear.

Can a Diagnostic Test Miss a Tumor?

There can be times when diagnostic testing may not pick up the tumor. It could be missed on imaging because the CT scan is non-contrast or poorly performed. It could also be missed because the tumor is small, and the scan field does not go completely through the parotid gland.

Some tumors fluctuate in size and could potentially be missed on a scan if they are small and less prominent when the scan is done.

There is no diagnostic test that will be able to show the surgeon the extent of the tumor’s involvement with the facial nerve. It is critical that a patient selects an experienced surgeon who knows how to successfully remove a tumor that is wrapped up in the facial nerve.

For more information on diagnostic testing for parotid tumors, click here to watch Video 2 in the Mayo Clinic Parotid Tumor Guide series.

Click here to learn more about this topic in our podcast series, Parotid Tumor Podcast.


1. Mayo Clinic. (2018, October 8.) Mayo Clinic Parotid Tumor Guide: Diagnostic Testing or Workup for a Parotid Tumor [Video File]. Retrieved by

2. The content in this section was drafted in consultation with Eric J. Moore, M.D., of the Mayo Clinic in Rochester, MN.