Minor Salivary Gland Polymorphous Adenocarcinoma With Local Recurrence After Seven Years: A Case Report

Polymorphous adenocarcinoma is a rare neoplasm of the minor salivary glands with an indolent behavior. Here, we report and describe the computed tomography (CT) and magnetic resonance imaging (MRI) of polymorphic adenocarcinoma in a 69-year-old patient who presented with local recurrence seven years after the initial treatment. On contrast CT, the primary lesion appeared heterogeneous and invaded the pterygopalatine fossa and the sphenopalatine foramen. The recurrent lesion on MRI showed a hypointense signal on the T1-weighted sequence, a hyperintense signal on the T2-weighted sequence, and heterogeneous enhancement with contrast. The patient underwent a new surgery for lesion resection and is currently under clinical and radiological follow-up. It is recommended to follow patients for at least 15 years after diagnosis, as local recurrences can occur up to 10 years after the initial treatment.