Histopathologic changes in parotid gland parenchyma after fine needle aspiration biopsy of a Warthin's tumour. A case report

Abstract

Fine needle aspiration biopsy of a non-tender tumour in the right parotid gland was performed in a 63-year-old man. A cytological diagnosis of Warthin's tumour was made. Six weeks later, the tumor was removed by a formal parotidectomy. During dissection of the marginal mandibular branch of the facial nerve, significant fibrosis in the surrounding soft tissues was noted, requiring resection of the nerve. We also found a metaplastic (infarcted) Warthin's tumour with focal necrosis surrounded by metaplastic squamous epithelium. There was extensive fibrosis within the adjacent atrophic parotid parenchyma, striated muscle and around peripheral nerves. Small arteries at the periphery of the tumour were occluded by thrombi. The authors believe that the fibrosis of the tissue adjacent to the tumour was more likely due to the ischemia than to a direct puncture trauma caused by the fine needle aspiration.