Pathology of Salivary Gland Tumours Flashcards
What are some causes of changes in salivary gland size?
- secretion retention
- chronic sialadenitis
- gland hyperplasia
- salivary neoplasms
- viral infection
What types of pathology can cause salivary secretion retention?
- mucocele
- duct obstruction
How do salivary gland neoplasms usually present?
- painless
- slow growing
- well defined
- may observe neurological change (eg facial nerve runs through parotid)
What is the epidemiology of salivary gland tumours?
- 10 per 100,00 of general population
- 3% of head & neck neoplasms
- 75% benign
What is an example of a viral infection that has an effect on the salivary glands?
Mumps
What is the most common type of salivary gland to experience tumours?
Parotid gland (15% are malignant)
What might be the first sign of a salivary gland neoplasm?
Localised swelling
Which type of salivary gland is most likely to experience a malignant tumour formation?
Sublingual (low change of tumour development, but when tumours develop here they are high risk of being malignant)
What are some clinical features seen in patients with tumours of the major salivary glands?
- asymmetry
- obstructions
- pain
- facial palsy (if in parotid)
What are the classification types of salivary gland tumours?
Epithelial Neoplasms
- benign
- malignant
Non-epithelial Neoplasms
- lymphoma
- sarcoma
Where is the most common area for development of minor/intraoral salivary gland neoplasms?
- junction of hard/soft palate
- Upper lip/cheek
How can salivary gland tumours be diagnosed?
- ultrasound guided fine need aspirate (FNA)
- core biopsy (more invasive)
- incisional biopsy
What problems can occur in diagnosing salivary gland tumours?
- high number of tumour types
- variation within tumour
- common features between types
- not all tumours fit the classification
What does NOS stand for in tumour definitions.
Not otherwise specified
What is the most common type of salivary gland tumour?
Pleomorphic adenoma (parotid most common)
How can the histology of pleomorphic adenoma be described?
Very varied “mixed tumour”
- duct epithelium
- myoepithelial cells
- myxoid areas
If a tumour is encapsulated, what might you assume?
It is benign
How long should you follow up with a patient that has had a pleomorphic adenoma?
5 year follow-up
- pleomorphic adenoma very commonly reoccurs
What percentage of pleomorphic adenomas become malignant?
5% (approx)
How are pleomorphic adenomas treated?
Wide local excision
What are malignant pleomorphic adenomas called?
carcinoma x pleomorphic adenoma
What percentage of benign salivary gland tumours are known as Warthin’s tumours?
15%
Where are you most likely to find a Warthin’s tumour?
Parotid gland
What social history is relevent in patients with Warthin’s tumour?
Pts tend to be smokers
How does the histology of Warthin’s tumours present?
- cystic
- distinctive epithelium
- lymphoid tissue
How are Warthin’s tumours treated?
Excision
What percentage of salivary tumours are salivary gland carcinomas?
15%
What are the varied histological patterns of adenoid cystic carcinoma that are seen?
- cribriform (swiss cheese)
- tubular
- solid
What is meant by perineural infiltration of an adenoid cystic carcinoma? What can this cause?
Tumour grows along the nerves in the area
- painful tumour
What is seen here?
Adenoid cystic carcinoma
What are mucoepidermoid carcinomas?
Malignancies that involve 2 cell types
- squamous
- glandular
How can mucoepidermoid carcinomas be differentiated?
cystic or solid
Why might a mucoepidermoid carcinoma be present intraosseously?
Jaw bones contain odontogenic epithelium, these are a source of mucous cells (multipotential type of epithelium)
When would you use Alcian blue staining?
When investigating mucous producing cells
Where is a polymorphous adenocarcinoma tumour located
Minor glands in palate
