Salivary gland tumours

Question 1

Most common benign tumours of salivary glands

Answer 1

Pleomorphic adenoma (most common tumour of parotid - 80%), Warthin tumour (10% parotid tumours)

Question 2

Most common malignant tumours

Answer 2

• Adenoid cystic carcinoma (most common malignancy in submandibular and sublingual glands)
• Mucoepidermoid carcinoma (most common malignant tumour of parotid gland)
• Malignant mixed tumours of the salivary glands
• Lymphoma***

Question 3

Imaging features pleomorphic adenoma

Answer 3

Enhancing, cystic mass (high T2) in parotid

DDx: mucoepidermoid carcinoma (same appearance), but uncommon 5% of tumours

Question 4

Imaging features Warthin tumours

Answer 4

Bilateral in 15%, cystic, variable enhancement

old, smokers

Question 5

Which tumour has risk to malignant degeneration

Answer 5

Pleomorphic adenoma 1.5% (higher if there longer)
Will not be cystic - dark on T1 and T2 (dark on T1 is bad sign - Mucoepidermoid and ACCs can be dark)

Need to excise all pleomorphic adenomas!

Question 6

Imaging features ACC

Answer 6

Enhancing mass with perineurial spread**
Mets seen in 50% of cases

NB: these can also arise in paranasal sinuses

Can spread to trigeminal nerve ganglion via foramen ovale and along the facial nerve

Question 7

Imaging findings sarcoidosis

Answer 7

• Bilateral, painless enlargement of parotid glands
  (Uvoparotid fever - Heerfordt snydrome - bilateral uveitis, parotid enlargement, facial nerve palsy - pathognomonic for sarcoid)
• Panda sign on Gallium-67

Question 8

Imaging findings Sjogren’s

Answer 8

• Atrophy/fatty replacement of salivary glands, with nodules and cysts, abN enhancement and calcs
• RISK OF LYMPHOMA (consider if new dominant mass)