Table of Contents
Definition / general | Clinical features | Treatment | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Cytology description | Cytology images | Positive stains | Negative stains | Electron microscopy description | Molecular / cytogenetics description | Differential diagnosisCite this page: Handra-Luca A, Hang JF. Warthin tumor. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/salivaryglandswarthin.html. Accessed February 3rd, 2023.
Definition / general
- Common tumor of parotid gland with double layer of epithelial cells resting on dense lymphoid stroma
- Also called papillary cystadenoma lymphomatosum papilliferum, adenolymphoma
- #2 most common benign salivary gland tumor (after pleomorphic adenoma)
Clinical features
- Almost always in parotid gland; 10% of parotid gland tumors
- 70% of bilateral salivary gland tumors are Warthin tumors
- Occasionally in oral cavity, larynx, cervical lymph nodes (Auris Nasus Larynx 2004;31:293)
- Usually male smokers age 40+ years
- Arises from incorporation of lymphoid tissue in parotid gland or induction of cystic and oncocytic changes by inflammatory infiltrate
- Associated with tuberculosis, Brucella mellitensi
- May occur synchronous with pleomorphic adenoma and salivary duct carcinoma
- Malignant change (1%) to lymphoma, Merkel cell carcinoma, adenocarcinoma, NOS, basal cell carcinoma, mucoepidermoid carcinoma, oncocytic carcinoma, salivary duct carcinoma, squamous cell carcinoma, Warthin adenocarcinoma
Treatment
- Surgical excision
- 2% recur after resection
Gross description
- Encapsulated, lobulated, pale gray surface, multicystic with mucinous / serous secretion, 10 - 15% multifocal / bilateral
- 2 - 5 cm
- May be fixed to overlying skin
- May undergo hemorrhagic infarction, particularly after fine needle aspiration
Microscopic (histologic) description
- Double layer of epithelial cells resting on dense lymphoid stroma with variable germinal centers
- Cystic spaces narrowed by polypoid projections of lymphoepithelial elements
- Surface palisading of oncocytic columnar cells with underlying discontinuous basal cells
- Occasional features are cilia, squamous metaplasia associated with infarct-like necrosis, mast cells, dendritic cells, mucin secreting cells, sebaceous cells
- Very rarely signet ring cells
- No myoepithelial component
Microscopic (histologic) images
Cytology description
- Squamous appearance of degenerated oncocytes
- Sheets of oncocytes and mixed population of lymphocytes in a characteristic dirty proteinaceous background
- Oncocytic sheets show an organized honeycombing or papillary arrangement and are typically cyanophilic at the periphery and bright orange at the center on Papanicolaou stain
- Oncocytes show densely granular cytoplasm, centrally located nuclei and small nucleoli
- Lymphocytes are mostly small mature cells
Cytology images
Contributed by Robin Pike, M.D. and Jen-Fan Hang, M.D.
Positive stains
Negative stains
- Amylase, vimentin, desmin, smooth muscle actin, EBV, HHV8
Electron microscopy description
- Oncocytes are stuffed with mitochondria with cup shapes or concentric ring forms but no partitions
Molecular / cytogenetics description
- Not clonal (Hum Pathol 2000;31:1377, Mod Pathol 2005;18:964), although cases with coexisting mucoepidermoid carcinoma are associated with t(11;19) and the CRTC1 / MAML2 fusion transcript (Genes Chromosomes Cancer 2008;47:309)
- Diploid, t(11,19), HHV8 DNA may be positive
Differential diagnosis
- Acinic cell carcinoma
- Squamous cell carcinoma: may resemble at fine needle aspiration