Pathology 3 - Salivary tumours Flashcards
What are causes for change in salivary gland size?
- secretion retention (mucocele or duct obstruction)
- chronic sialadenitis
- gland hyperplasia (sialosis, sjogrens)
- neoplasm
What are causes of chronic sialadenitis?
- bacterial from xerostomia
- viral
- more common in parotid
What are signs of salivary tumour?
- localised swelling
- neurological change in facial nerve
- painless
- slow growing
- well defined
Describe the epidemiology of salivary tumours.
- uncommon
- 3% of head and neck neoplasms
- 75% are benign
What is the most common gland for salivary tumours?
Parotid - only 15% malignant
What is the most common gland for malignant salivary tumours?
Sublingual - 0.5% of tumours overall, 80% of these malignant
What is the general rule for salivary gland malignancy?
The smaller the gland the more likely to be malignant
What are the different histological typing of tumours?
Epithelial
- benign or adenoma
- malignant or adenocarcinoma
Non-epithelial
- lymphoma
- sarcoma
What are the clinal features of a major salivary gland tumour?
- lump in gland
- asymmetry
- obstruction
- pain or facial palsy (late sign for parotid)
What are the clinal features of a minor salivary gland tumour?
- often found at junction of hard/soft palate
- upper lip or cheek
- ulcerate (late sign of malignancy)
- can be ectopic in tongue
What are the different biopsy types suitable for salivary gland tumours?
- FNA
- core biopsy
- incisional biopsy
What does NOS indicate?
Cancer that is not otherwise specified (does not fit any category)
What are the features of pleomorphic adenoma?
- 75% of salivary tumours, most common in parotid
- slow growth, painless
- varied histopathology, capsule is variable (benign tumours usually incomplete capsule)
What cells are common to see in pleomorphic adenoma?
- duct epithelium
- myoepithelium cells
- myxoid and chondroid areas
What is the treatment of pleomorphic adenoma?
Wide local excision
What problems are associated with pleomorphic adenoma?
- recurrence is common due to multifocal presentation
- progression to carcinoma 5%
What are the features of adenolymphoma?
- aka warthin’s tumour
- related to smoking
- 15% of salivary tumours, most common in parotid
- occasionally bilateral or multifocal
- recurrence is low, malignant change low
What is the histology of adenolymphoma?
- cystic
- distinctive epithelium
- lymphoid tissue
What is the treatment of adenolymphoma?
Excision
What are the features of adenoid cystic carcinoma?
- 5% of tumours, more common in minor glands
- local spread is common to nerves and bone
- perineural pain presents with dull continuous pain
- varied histology
What histological patterns are seen in adenoid cystic carcinoma?
- cribriform
- tubular
- solid
What problems are associated with adenoid cystic carcinoma?
- difficult to treat
- recurrence high
- prognosis poor at 20 years
- late spread to lungs via metastasis in blood
What are the common features of mucoepidermoid carcinoma?
- 3-5% of tumours
- cystic or solid
- unpredictable
- lymphatic spread rare
- can be intraosseous (ectopic or odontogenic epithelium has multiple transformation potential)
What cells are common to see in mucoepidermoid carcinoma?
- squamous (epidermoid)
- glandular (mucous)
What stain is used to visualise mucous cells?
Alcian blue
What are other salivary carcinomas of note?
- acinic cell carcinoma (rare, parotid, varied histology)
- polymorphous adenocarcinoma (minor palatal glands, perineural spread)
