Salivary gland pathology

Question 1

What is the most common site for almost all tumours?

Answer 1

Parotid gland

Question 2

Are most parotid gland tumours benign or malignant?

Answer 2

Benign

Question 3

Are most small salivary gland tumours benign or malignant?

Answer 3

Malignant

Question 4

What are some benign salivary gland tumours?

Answer 4

Pleomorphic adenoma (Most common)
Warthin’s tumour

Question 5

What are some malignant salivary gland tumours?

Answer 5

Mucoepidermoid carcinoma
Adenoid cystic carcinoma

Question 6

Who is most at risk of pleomorphic adenoma?

Answer 6

• female
• 3-6th decade
• Radiation exposure

Question 7

Describe the macroscopic appearance of pleomorphic adenoma

Answer 7

Well circumscribed, light tan to grey

Question 8

Describe the microscopic appearance of pleomorphic adenoma

Answer 8

Highly variable epithelial and myoepithelial cells in chondromyxoid stroma

Question 9

What are some risk factors of Warthin’s tumour?

Answer 9

• Male
• Over 50
• Smoking

Question 10

Describe the macroscopic features of Warthin’s tumour

Answer 10

Well circumscribed, light grey, cystic
Bilateral and multi-centric

Question 11

Describe the microscopic appearance of Warthin’s tumour

Answer 11

Bilayered oncocytic epithelium with lymphoid stroma

Question 12

When should a malignant salivary gland tumour be suspected?

Answer 12

Young and a painful mass

Question 13

What is the prognosis of low grade mucoepidermoid carcinoma?

Answer 13

> 90% 5 year survival

Question 14

What is the prognosis of high grade mucoepidermoid carcinoma?

Answer 14

< 60% survival

Question 15

What genetic mutation is associated with mucoepidermoid carcinoma?

Answer 15

MECT1-MAML2 fusion

Question 16

Describe the macroscopic appearance of mucoepidermoid carcinoma?

Answer 16

Can be well circumscribed or infiltrative

Question 17

Describe the microscopic appearance of mucoepidermoid carcinoma?

Answer 17

Variable mix of squamous, mucous and intermediate cells, with solid and cystic components

Question 18

Where do adenoid cystic carcinomas affect?

Answer 18

Most commonly the parotid, but are also the most common malignant tumours of the palate

Question 19

What is the prognosis of adenoid cystic carcinoma?

Answer 19

50-70% 10-year survival

Question 20

What is a possible complication of adenoid cystic carcinoma?

Answer 20

Perineural invasion - associated pain or loss of function

Question 21

Describe the macroscopic appearance of adenoid cystic carcinoma

Answer 21

Greyish/white infiltrative mass

Question 22

Describe the microscopic appearance of adenoid cystic carcinoma

Answer 22

Small, uniform cells with little cytoplasm in solid, tubular or cribiform plate

Question 23

How do salivary gland tumours present?

Answer 23

Mass in the affected gland which may or may not have been present for a long time

Signs of CN VII (facial nerve) damage e.g. facial nerve palsy are associated with malignant parotid tumours

Question 24

What is shown?

Answer 24

Parotid gland tumour

Question 25

What are some investigations required in salivary gland tumours?

Answer 25

• US
• FNA
• Staging
  
  • CT - local relations
  • MRI - deep lobe of parotid, relations with CN-VII

Question 26

How are salivary gland tumours managed?

Answer 26

• Salivary gland tumours are nearly always resected e.g. superficial or total parotidectomy
  
  • Usually in their early stages it is not possible to distinguish a benign tumour from a malignant one
  • There is a risk of malignant transformation of adenoma if left alone

Question 27

What are some structures at risk in cases of parotidectomy?

Answer 27

Facial nerve
Retromandibular vein
External carotid artery

Question 28

What is infection of the salivary glands known as?

Answer 28

Sialadenitis

Question 29

What are some causes of sialadenitis?

Answer 29

• Viral (mumps - paramyxoma virus)
• Bacterial

Question 30

What is stone formation in the salivary glands known as?

Answer 30

Sialolithiasis