Idiopathic necrotizing sialometaplasia of parotid gland

Necrotizing sialometaplasia (NS) is an uncommon non-neoplastic, self-limiting inflammatory condition of the salivary glands. NS of major salivary glands is rare and simulates malignancy. If it is seen at this location, most of the cases are due to ischemia caused by vessel injury secondary to previous dental procedure or parotid gland surgery. We present a case of a parotid swelling that appeared as Warthin tumor on fine needle aspiration cytology (FNAC). On histology it turned out to be NS of parotid gland. The well known etiologies were absent in this case and hence it was labeled as idiopathic.