Doctors don’t regularly come across undiscovered bits of human anatomy, but a team of physicians recently reported a never-before-described set of salivary glands in patients’ necks. The first hint of this new gland emerged while Wouter Vogel, a radiation oncologist at the Netherlands Cancer Institute (NCI), was probing for damage to salivary glands after radiotherapy for cancer in the head, neck, or brain—injuries that can lead to issues such as problems with digestion, speech, and an increase in oral infections. While going through these scans, he found something usual.

Vogel was using a new technique for detecting cells in the salivary glands—PSMA PET/CT, a form of combined positron emission tomography (PET) and computed tomography (CT) that uses a radioactive tracer that binds to a prostate-specific membrane antigen (PSMA). This method is typically used to detect prostate cancer, but in a prior study, Vogel and his colleagues had found that it also labels salivary gland cells, where PSMA is also expressed. Humans have three major salivary glands and approximately 1,000 minor ones. “This scan is extremely sensitive for the salivary glands,” Vogel says. “So we can see more than ever before.”

What he saw was an unexpectedly high level of labeling in the upper section of the throat known as the nasopharynx, where only minor salivary glands are supposed to be found.

When Vogel first observed the unanticipated signal, he says he was confused—salivary gland cells were not thought to be abundant in this location. Immediately, he sought a second opinion from his colleague Matthijs Valstar, an oral and maxillofacial surgeon at the NCI. “You never believe something until you have some feedback from others,” Vogel tells The Scientist. “But we agreed that it really was an unexpected and significant signal that requires further investigation.”

More details can be found at https://www.the-scientist.com/news-opinion/scientists-discover-new-human-salivary-glands-68068