
ABOVE: A 3-D reconstruction from histological slides (inset on right) of the newly discovered tubarial gland (yellow; ducts in light blue). The torus tubarius cartilage is colored dark blue and muscle is pink.
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."
Comment: Contrary to the claim at the beginning of the article, this is actually just the latest new organ scientists have discovered in recent years: