Warthin tumor

Last revised by Arlene Campos on 11 Jan 2024

Warthin tumors, also known as lymphomatous papillary cystadenomas, are benign, sharply demarcated salivary gland tumors, almost exclusively encountered in the parotid gland. They are of lymphoid origin and may be bilateral or multifocal in up to 20% of cases and are the most common neoplastic cause of multiple solid parotid masses. 

Warthin tumors are the 2nd most common benign parotid gland tumor (after pleomorphic adenoma) and represent up to 10% of all parotid tumors. They are the most common bilateral or multifocal benign parotid tumors. They typically occur in older age (6th decade) and are twice as common in men (2.2:1) 11.

  • smoking

  • irradiation

Patients typically present with painless parotid swelling.

They tend to favor the parotid tail region at the level of the mandibular angle. In <10% cases, they are found elsewhere, including the submandibular glands, cervical lymph nodes, and ectopic nests of salivary tissue, e.g. larynx, maxillary antrum, oral cavity (e.g. lower lip, buccal mucosa) 11,12.

They are often multicentric (20%) and are usually small (1-4 cm). They have a typically heterogeneous appearance on all modalities, often with cystic components (30%). The tendency to undergo cystic change is greater than any other salivary gland tumor 4,5.

Most tumors tend to be ovoid, with well-defined margins and multiple irregular, small, sponge-like anechoic areas 10. Tumors that are large (e.g. >5 cm) tend to have a higher proportion of cystic content than smaller lesions had and in some cases can be composed almost entirely of cystic material. They are often hypervascular.

  • classic appearance is a well-defined heterogeneous solid cystic lesion within the superficial lobe of parotid/parotid tail

  • well defined

  • no calcification

  • cystic changes appear as intralesional lower attenuation

  • moderate enhancement

  • presence of a mural nodule is strongly suggestive of Warthin tumor

  • can be often seen bilaterally

  • T1: low to intermediate signal with cyst containing cholesterol components containing focal high signal 2

  • T2: heterogeneous and variable signal intensity

  • T1 C+ (Gd): cystic components do not take up contrast while solid parts usually enhance 1

Warthin tumors often shows uptake with Tc99-pertechnetate, thallium, and FDG-PET 7.

They are benign with an extremely low incidence of malignant transformation (~1%). Some advocate surgical excision while others favor conservative management with follow-up imaging. The commonest surgery is a superficial parotidectomy and recurrence rate is low, less than 5% in one of the largest published series 11,12.

These lesions were first described in 1929 by an American pathologist, Aldred Scott Warthin 13,14.

Possible imaging differential considerations include:

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