Warthin's Tumour

The Concept

Warthin's tumour (adenolymphoma, or papillary cystadenoma lymphomatosum) is the second commonest benign salivary tumour, occurring almost exclusively in the parotid. Its distinctive histology — epithelial (glandular) tissue set in a prominent lymphoid stroma, with cystic spaces — gives it its old name 'adeno-lymphoma', though it is entirely benign and not a lymphoma. This lymphoid content also explains its behaviour on imaging.

Clinical Features

It has a striking demographic that makes it a favourite in vivas: it occurs typically in older men and is strongly associated with smoking. It presents as a soft, cystic, slow-growing swelling in the tail of the parotid, and is notable for being the salivary tumour most likely to be bilateral or multifocal. Because it contains functioning tissue that takes up technetium, it appears as a 'hot' spot on a pertechnetate scan — a characteristic (if now rarely used) feature.

Management

Diagnosis is by FNAC and imaging. It is benign with negligible malignant potential, so treatment is surgical excision (superficial parotidectomy or a more limited excision), which is curative; in an elderly, frail patient a confidently diagnosed asymptomatic Warthin's tumour may even be observed.

A Note on Diagnosis

Diagnosis is by FNAC and imaging (ultrasound/MRI); the combination of an older male smoker with a soft cystic parotid-tail swelling, possibly bilateral, is highly suggestive. Because it is benign, the main purpose of investigation is to confidently distinguish it from a malignant tumour so that appropriate (often conservative) management can be chosen.

Pathogenesis & Significance

Warthin's tumour is thought to arise from salivary duct epithelium entrapped within intra-parotid lymph nodes during development, which explains its unique lymphoid stroma and its confinement to the parotid (the only salivary gland with lymph nodes inside it). Its strong link with smoking is a consistent epidemiological finding. Clinically its importance is largely in being recognised as benign — so that an older male smoker with a soft, sometimes bilateral parotid-tail swelling is not over-treated as if it were a cancer.

Management & the Frail Patient

Because Warthin's tumour is entirely benign and slow-growing, management is individualised: a fit patient is offered excision (superficial parotidectomy or extracapsular dissection) which is curative, whereas a confidently diagnosed, asymptomatic tumour in a frail elderly patient may be safely observed. Bilateral or multifocal disease is recognised so that both sides are assessed. The key clinical service the diagnosis provides is sparing such patients the anxiety and over-treatment appropriate only to malignant tumours.

The Bottom Line

The clinical service the Warthin's diagnosis provides is confident recognition of benignity in the older male smoker, sparing over-treatment; excision is curative when needed, and bilateral or multifocal disease is simply looked for and dealt with on its merits.

The only salivary tumour that takes up technetium.

• Warthin's tumour (adenolymphoma) = second commonest benign salivary tumour; almost always parotid.
• Histology: epithelial tissue in a lymphoid stroma with cystic spaces (benign, not a true lymphoma).
• Classic: older men, smokers; soft cystic swelling in the parotid tail; often bilateral/multifocal; 'hot' on pertechnetate scan.
• Benign — treat by excision (curative); observation is reasonable in the frail elderly.