Warthin’s tumor is a benign, slow-growing tumor, found almost exclusively in the parotid gland. We report the case of a patient with a pseudo-malignant extra-parotid Warthin’s tumor with inflammatory changes. An 84-year-old woman was admitted to our hospital with a painless mass in the right breast. She was diagnosed by vacuum-assisted biopsy as having invasive carcinoma of the right breast. FDG-positron emission tomography (FDG-PET) was performed, which also showed a mass in the left supraclavicular fossa (SUVmax=33.2). The mass was suspected as a metastatic lymph node or a recurrent thyroid cancer, because she had been diagnosed as having papillary thyroid carcinoma and been treated by total thyroidectomy about 20 years earlier. Therefore, a left neck dissection was performed immediately. However, histological examination showed the typical findings of Warthin’s tumor with severe inflammation. There was no evidence of malignancy.
It is an accepted etiologic hypothesis that Warthin’s tumor originates from ectopic salivary gland tissue in lymph nodes. It is thought that extra-parotid Warthin’s tumors often develop in the neck lymph nodes. When encountering a neck tumor with inflammatory changes, Warthin’s tumor should be included in the differential diagnosis.
