Salivary Gland Pathology
Salivary gland pathology is the area of oral and maxillofacial pathology concerned with diseases of the major (parotid, submandibular, sublingual) and minor salivary glands. It spans inflammatory and infectious conditions, obstructive disorders caused by stones or strictures, benign and malignant neoplasms, and disorders of secretory function such as dry mouth, including its autoimmune form in Sjögren syndrome.
Definition
Salivary gland pathology encompasses the structural and functional diseases of the salivary glands and their ducts, classified into inflammatory/infectious, obstructive, neoplastic, and secretory (hypofunction) categories.
Scope
This area orients the reader to the families of salivary gland disease and to how they are distinguished clinically and histologically. It groups four topics: inflammation and sialadenitis, sialoliths and ductal obstruction, benign and malignant tumours, and xerostomia with Sjögren syndrome. It is a reference and educational overview of disease categories, not a source of diagnostic or treatment instructions.
Sub-topics
Core questions
- Which gland or glands are affected, and is the process diffuse or focal?
- Is the disorder inflammatory, obstructive, neoplastic, or functional?
- Does a salivary swelling represent infection, a stone, a cyst, or a tumour?
- How is glandular secretory function assessed and related to symptoms of dry mouth?
Key concepts
- Major versus minor salivary glands
- Sialadenitis (acute, chronic, autoimmune)
- Sialolithiasis and ductal obstruction
- Benign and malignant salivary neoplasms
- Salivary hypofunction and xerostomia
- WHO histological classification of salivary tumours
- Sialography and sialendoscopy
Mechanisms
Salivary glands secrete saliva through a branching ductal system, and most of their diseases reflect disturbances of this anatomy and physiology. Obstruction by a calculus or stricture causes retrograde stasis and predisposes to inflammation; ascending bacterial infection or reduced flow produces sialadenitis; chronic immune-mediated injury, as in Sjögren syndrome, destroys acinar tissue and lowers secretion; and neoplasia arises from the diverse epithelial and myoepithelial cell populations of the gland, giving rise to a wide histological spectrum of benign and malignant tumours.
Clinical relevance
Salivary gland disease commonly presents as glandular swelling, pain related to eating, a discrete mass, or a complaint of dry mouth, and distinguishing these patterns is a routine task in dentistry, oral and maxillofacial pathology, and head and neck practice. This overview describes how the disease categories are organised and recognised; it is educational and does not provide individual diagnostic or treatment guidance.
Epidemiology
Inflammatory and obstructive conditions are the most frequent salivary diseases, while salivary gland tumours are comparatively uncommon and arise most often in the parotid, where the majority are benign. The proportion that is malignant rises in the submandibular, sublingual, and minor glands. Sjögren syndrome is among the more common systemic autoimmune diseases and is a leading cause of chronic salivary hypofunction.
History
Description of salivary stones and gland swellings dates to antiquity, but systematic classification advanced in the twentieth century with histopathological study of tumours and with the World Health Organization classifications of salivary neoplasms. Imaging and minimally invasive techniques such as sialography and, more recently, sialendoscopy reshaped the diagnosis and management of obstructive disease.
Related topics
Seminal works
- seethala-who-2017
- brito-zeron-2016
Frequently asked questions
- What are the main categories of salivary gland disease?
- They are usually grouped as inflammatory or infectious (sialadenitis), obstructive (stones and strictures), neoplastic (benign and malignant tumours), and functional (salivary hypofunction and dry mouth, including Sjögren syndrome).
- Which salivary gland is most often involved by tumours?
- Most salivary gland tumours arise in the parotid gland, and the majority of parotid tumours are benign; the likelihood that a tumour is malignant is higher in the submandibular, sublingual, and minor glands.