TUBARIAL ORGAN-LIKE GLANDULAR TISSUE – A COMPARATIVE HISTOLOGY STUDY IN HUMANS AND CANINES

Purpose: A "new organ at risk" with characteristics of glandular tissue above the torus tubarius has been accidentally reported on PSMA PET/CT. Based on its location, that "finding" was named "tubarial (salivary) glands". Because the description of a potentially "new" body structure in the 21st century was generating scientific interest and controversy, the current study aimed to verify the presence of these structures in two biological species – humans and canines. Material/Methods: Tissue blocks were obtained from the torus tubarius of three human and canine cadavers and examined by hematoxylin and eosin, periodic acid Schiff (PAS), and Alcian blue staining. The observed results were analyzed by comparing them to samples of human palatine, parotid, submandibular, sublingual, and small palatine salivary glands, as well as canine tissue samples from the area of torus tubarius. Results: The dissected areas from the human torus tubarius showed submucosal aggregates of predominantly mucous gland tissue, a low number of serous acini, draining ducts, a capsule and trabeculae with blood vessels penetrating inside. Almost similar findings were observed in the canine samples. Conclusion: The description of the "tubarial glands" in humans, and confirmed in another biological species, sparked a scientific interest which opened the door to further digging into the thrust area with more evidence from different studies. More research is needed to resolve the controversies about the "tubarial (salivary) glands", formulate a consensus, and establish their place in anatomy and clinical practice.