A 50-year-old man presents with a slow-growing, painless lump below the left ear, present for 2 months, with no other symptoms. The lump is in the parotid region. What is the most likely diagnosis?

Answer: E. A pleomorphic adenoma of the parotid

Pleomorphic adenoma

A slow-growing, painless parotid swelling below the ear in a middle-aged adult is most likely a pleomorphic adenoma (benign mixed parotid tumour), the commonest salivary gland tumour.

Why benign tumour

• The parotid is the most common site for salivary tumours; most arise in the superficial lobe.
• They present as slow-growing, painless swellings located below, in front of, or above the angle of the ear.
• The majority (80-90%) of parotid tumours are benign.

Features that would suggest malignancy

• Facial nerve weakness, rapid enlargement, pain, skin induration/ulceration, or cervical lymphadenopathy.

Next step

• Assessment with ultrasound and FNAC (and CT for further imaging) to characterise the lesion before treatment.