Parotid tumours

Question 1

Which salivary gland is the largest?

Answer 1

Parotid.

Question 2

Are parotid tumours mainly benign or malignant?

Answer 2

80% are benign + 20% are malignant.

Question 3

Examples of benign parotid tumours?

Answer 3

· Pleomorphic adenoma - can undergo malignant change.

· Warthin’s tumour (adenolymphoma).

Question 4

Examples of malignant parotid tumours?

Answer 4

· Mucopeidermoid carcinoma.
· Adenoid cystic carcinoma.
· Acinic cell carcinoma.
· SCC.
· Adenocarcinoma.

Question 5

Which malignant parotid tumour grows along nerves?

Answer 5

Adenoid cystic carcinoma.

Question 6

Which malignant parotid tumour is most common in children?

Answer 6

Acinic cell carcinoma.

Question 7

What are the potential risk factors?

Answer 7

· Direct radiation exposure.
· EBV infection.
· Smoking - Warthin’s tumour.
· Genetic alterations - p53 mutations.

Question 8

What are the typical signs and symptoms of a parotid tumour?

Answer 8

· Slowly enlarging mass which is typically painless. 
· Malignancy features.
. Dysphagia.
· Hoarseness.
· Airway obstruction.

Question 9

What are the common malignant signs and symptoms?

Answer 9

· Facial nerve palsy.
· Overlying erythema or ulceration.
· Pain.

Question 10

What investigations would you do to help diagnose a parotid tumour?

Answer 10

· Physical exam - feel for swelling along head, neck, jaw.
· FBC, U&Es and CRP.
· USS with FNA.
· Staging CT scan of neck and thorax.

Question 11

Differentials?

Answer 11

· Sialolithiasis.
· Lithiasis.
· Chronic sialadenitis.
· Autoimmune disease.
· Lymphoproliferative disorders. 
· HIV.

Question 12

What are the current surgical treatment options?

Answer 12

· Excision.

· Neck dissection - e.g. parotidectomy.

Question 13

What are the current non-surgical treatment options?

Answer 13

· Radiotherapy following surgery.

· Chemotherapy if palliative.

Question 14

What complications can occur?

Answer 14

· Post-op haematoma - can cause airway obstruction.
· Facial nerve damage or sacrifice intra-operatively.
· Frey’s syndrome.
· Salivary fistula.

Question 15

What is Frey’s syndrome?

Answer 15

· Caused by injury to the auriculotemporal nerve, typically after surgical trauma to the parotid gland.
· Late complication following parotidectomy.
· Autonomic fibres supplying the gland reform inappropriately.
· Stimulus to salivate results in inappropriate response of redness and sweating.