Presentation
Incidental parotid lesion detected on serial MRI follow up for acoustic schwannoma
Patient Data
Sharply circumscribed left parotid mass contains small cystic areas and a single coarse focus of calcification.
No other left parotid lesion identified.No abnormal soft tissue density or expansion of the pterygopalatine fossae, stylomastoid foramina or foramina ovale.
Previous right retrosigmoid craniectomy and right parietal ventriculoperitoneal shunt noted.
MACROSCOPIC DESCRIPTION: "Left parotid": A firm and rubbery parotid gland, 19.3g, 50x25x25mm. At one side there is a separate rubbery structure attached to the parotid gland, 30x16x10mm. The resection surface is inked in silver. The parotid is uniform and yellow. The cut surface of the attached mass contains foci of solid cream and white tissue.
MICROSCOPIC DESCRIPTION:
Sections of the parotid show a well-circumscribed tumor. It contains bilayered oncocytic epithelium, surrounded by scattered lymphoid follicles in the stroma. The epithelial cells show no nuclear atypia.
No evidence of malignancy is identified. The remaining parenchyma is normal. 3 adjacent benign lymph nodes are present. The tumor is completely excised with all clear margins. The features are those of a Warthin tumor.
DIAGNOSIS:
Left parotid: Warthin tumor, completely excised.
Case Discussion
Key learning points:
- Calcification is unusual in Warthin tumors
- Warthin tumors are the second most common parotid mass