Diagnostic features and therapeutic management of accessory parotid gland tumours: a retrospective cohort analysis

The accessory parotid gland (APG) is a common anatomical variant, situated adjacent to Stensen's duct and anatomically separate from the main body of the parotid gland. While often healthy, this tissue can give rise to neoplasms. This retrospective cohort analysis investigated the diagnostic features and therapeutic management of these rare tumours. The records of 647 patients with parotid gland disease treated at a single Maxillofacial Surgery Unit from 1988 to 2023 were analysed, selecting 17 patients with confirmed APG tumours for detailed analysis. The mean age of the included patients was 52 years, with a slight female predominance (58.8%). The malignancy rate was notably high at 41.1%. Benign tumours were histologically confirmed as pleomorphic adenomas, while malignant diagnoses included adenocarcinoma, adenoid cystic carcinoma, carcinoma ex pleomorphic adenoma, and non-Hodgkin lymphoma. Importantly, some malignancies were initially misdiagnosed as benign or indeterminate by fine needle aspiration cytology. Surgical management varied, with total parotidectomy reserved for all confirmed malignant tumours. For benign and indeterminate cases, excision of the APG with associated partial parotidectomy was preferred over more conservative techniques. The most common complications (temporary facial palsy and salivary fistula) occurred in patients who underwent partial parotidectomy. The conclusions of this research emphasize that due to the substantially elevated malignancy risk and the limited reliability of preoperative cytology, a cautious, high-index-of-suspicion approach is necessary for all mid-cheek masses, and a more radical surgical approach is often warranted to ensure adequate tumour clearance.