Scientists have found a new organ in the throat while carrying out prostate cancer research.
It is thought the discovery could help reduce the side effects of some cancer treatments.
While scanning for cancerous cells, scientists in the Netherlands discovered a set of salivary glands, around 1.5in (3.8cm) in length, in the upper part of the throat behind the nose - the nasopharynx.
Until now, there were three known large salivary glands in humans: one under the tongue, one under the jaw and one at the back of the jaw, behind the cheek.
While in the nasopharynx, it was previously thought there were only up to 1,000 microscopically small salivary or mucous glands in this area.
"Imagine our surprise when we found these," radiation oncologist Wouter Vogel said.
Dr Vogel was carrying out research on the side effects of radiation on the head and neck with oral and maxillofacial surgeon Matthijs Valstar, when the discovery was made.
In order to check if their findings were just a one-off or not, the pair then teamed up with UMC Utrecht hospital and discovered that all 100 people whose scans they studied had a set of these glands.
The discovery could prove beneficial to cancer patients in the future as radiation therapy can make salivary glands produce less saliva, leading to dryness in the mouth.
Damage to salivary glands from radiation therapy can also leave people struggling to eat, speak and swallow.
"For most patients, it should technically be possible to avoid delivering radiation to this newly discovered location of the salivary gland system in the same way we try to spare known glands," Dr Vogel explained.
"Our next step is to find out how we can best spare these new glands and in which patients.
"If we can do this, patients may experience less side effects which will benefit their overall quality of life after treatment."
The pair from the Netherlands Cancer Institute have named the newly discovered organs the tubarial salivary glands due to their location over a piece of cartilage called the torus tubarius.
The salivary glands were discovered while the researchers scanned for prostate cancer cells because a radioactive tracer used to detect them is also good at detecting salivary gland tissue.
During the study, a combination of CT scans and positron emission tomography (PET) scans called PSMA PET-CT.
In PSMA PET-CT scanning, doctors inject a radioactive "tracer" into the patient.
This tracer binds well to the PSMA (prostate-specific membrane antigen) protein, which is elevated in prostate cancer cells.
PSMA PET-CT scanning also happens to be very good at detecting salivary gland tissue, which is also high in PSMA.
What are the signs and symptoms of prostate cancer?
According to Prostate Cancer UK, the common symptoms of an enlarged prostate are:
a weak urine flow
needing to urinate more often, especially at night
a feeling that your bladder has not emptied properly
difficulty starting to urinate
needing to rush to the toilet - or leaking urine before you get there
blood in your urine
Men are urged to visit their GP if they suffer from any of the above.
The symptoms can be caused by other medical problems, lifestyle factors or certain medicines and may be unrelated to the prostate.
Read Prostate Cancer UK's guide to diagnosis and treatment for more information.