Salivary Gland Disease Flashcards
Define ‘Agenesis’
- Developmental abnormality
- Where an organ fails to develop during embryonic growth
- Due to absence of primordial tissue
Define ‘Atresia’
- Developmental abnormality
- Where an orifice/ passage in body is closed/ absent
Define ‘Aplasia’
- Developmental abnormality
- Where an organ/ tissues fail to develop or function normally
e.g. ectodermal dysplasia
Define ‘Hypoplasia’
- Developmental abnormality
- Where an organ/ tissues are underdeveloped or incompletely developed
- Due to reduced number of cells
What may results as a direct major trauma to the nerves innervating the salivary glands?
- Fraye’s syndrome
- Gustatory facial sweating; instead of producing saliva in mouth
Which nerves of the parasympathetic division of the ANS innervates the salivary glands?
- PAROTID = Glossopharyngeal n. (CN IX); otic ganglion
- SUBMANDIBULAR/ SUBLINGUAL = Facial n. (CN VII); submandibular ganglion
How is a ranula managed?
- Fenestrate & drain
- If recurrence –> surgical removal of that damaged minor salivary gland
Describe the histology of a mucocele
- Cystic cavity containing saliva and macrophages (foam cells; looks like soap bubbles)
- Surrounded by granulation tissue wall to contain saliva from leaking
What is necrotising sialometaplasia?
- Benign ulcerative vascular lesion of the hard palate
- Usually painless and self-healing
- Vasospasm of greater palatine vessels –> ischaemia/ infarction of minor salivary glands
What differentiates necrotising sialometaplasia from a carcinoma?
- Bilateral and symmetrical; v few cancers present like this
What is the aetiology of necrotising sialometaplasia?
- Small vessel ischaemia/ infarction
- Smoking
- Trauma
Describe the histology of necrotising sialometaplasia
- Slough surface
- Hyperplasia of surface epithelium (seen as blobs further down from outer surface; ‘pseudo-epitheliomatous hyperplasia’)
- Squamous metaplasia of ducts
- Necrosis of salivary acini
- Inflammation
=> MAY LOOK CANCEROUS but normal cells which are hyperplastic!
Which medications are most associated with dry mouth?
- ANTIMUSCARINICS (anti-acetylcholine drugs; synapse) = Amitriptyline (26% reduction)
- DIURETICS = Bendroflumethiazide (10% reduction)
- LITHIUM (bipolar)
Describe the histology of a MINOR salivary gland in a patient with Sjogren’s
- Focal lymphocytic sialadenitis (focal collection of lymphocytes)
- -> each collection = 50+ lymphocytes
- -> at least 1 collection of 4mm2
- Acinar loss
- Fibrosis
Describe the histology of a MAJOR salivary gland in a patient with Sjogren’s
- Lymphocytic infiltration extending into WHOLE lobule
- Acinar atrophy
- Hyperplastic ductal epithelium = MYOEPITHELIAL ISLANDS (eventually occludes duct)
What are some oral complications of Sjogren’s?
- Oral infections (bacterial; stapyloccocal, fungal; candidal)
- Increased caries risk
- Functional loss (speaking, chewing, swallowing)
- Poor denture retention
- Salivary lymphoma (NHL; 1-5%)
What can be commonly found in the history of a patient with a subacute duct obstruction?
- Swelling associated with meals
- Slow and progressive growth
- Buccal mucosa may feel like gravel
- Mucoceles may be associated
What are the causes of subacute duct obstructions?
- Sialoliliths (stones)
2. Mucous plugging (slowing down of mucous –> calcify)
What investigations can be done for subacute duct obstructions?
- Low dose plain XR (usually submandibular involvement —> lower true occlusal)
- Sialography (infection free only!)
- Isotope (if think gland is dead/ stopped functioning)
What is the management for subacute duct obstructions?
- Surgical removal of stone
- Sialogrpahy; ‘washing’ effect (if ‘no stone’ case)
- Gland removal (fixed swelling)
What may a subacute duct obstruction lead to if left untreated?
Chronic sialadenitis (infection follows)
What are the percentage of salivary tumours for each salivary gland?
- Parotid = 80%
- Submandibular = 10%
- Sublingual = 0.5%
- Minor = 10%
What are the percentage of salivary tumours for each salivary gland that are MALIGNANT?
- Parotid = 15%
- Submandibular = 30%
- Sublingual = 80%
- Minor = 45%
What are the two types of EPITHELIAL neoplasms found in salivary glands?
- Adenomas
- Adenocarcinomas
What are the two types of NON-EPITHELIAL neoplasms found in salivary glands?
- Lymphomas (lymphocytes)
- Sarcomas (CT)
Describe the clinical AND histological presentation of a pleomorphic adenoma
- CLINICALLY
- -> Swelling that is slow growing
- -> Not fixed to other tissues
- HISTOLOGICALLY
- -> ‘Mixed tumour’
- -> Benign, well-defined
- -> ‘Duct-like’ structures; myoepithelial cells
- -> Myxoid and condroid areas
- -> Fibrous capsule (variable- complete/ incomplete)
What is the treatment for a pleomorphic adenoma?
Wide local excision (can recur; follow up 5yrs)
What are the complications if a pleomorphic adenoma if left untreated?
Malignant change –> carcinoma ex-pleomorphic adenoma
What is an adenolymphoma?
And which gland is it most commonly associated with?
- Benign cystic tumour of the salivary glands
- Containing abundant lymphocytes
- Parotid gland
What is the treatment for an adenolymphoma?
Excision
Describe the histology of adenolymphomas
- Cystic (spaces)
- Distinctive epithelium (oncocytic)
- Lymphoid tissue abundant
What is a adenoid cystic carcinoma?
- Slow growing malignant neoplasm arising from glandular tissues
- Commonly seen in minor salivary glands
- Distinct histology
- Spread seen = perineural, lymphoid, bone
Describe the histology of an adenoid cystic carcinoma
- 3 patterns = cribiform, tubular or solid
- -> Cribiform “swiss cheese” due to cystic spaces
What is a mucoepidermoid carcinoma?
- Painless, fixed, slowly growing neoplasm of salivary gland origin
Describe the histology of a mucoepidermoid carcinoma
- 3 types of distinct cells seen = squamous (epidermoid), glandular (mucous-secreting) and “intermediate” cells
- Grading/ differentiation = cystic or solid
