Background: Superficial parotidectomy superceded enucleation in parotid pleomorphic adenomas (PA) due to high recurrence rates, ascribed at least partially, to PAs commonly having a deficient capsule. Extracapsular dissection is an increasingly popular technique which may reduce the risk of CN7 palsy. However, this may predispose to incomplete resection in capsule deficient tumours increasing the risk of recurrence. In this study, we are attempting to identify how frequent capsule deficient PAs are in our institution, as well as describing the frequency of procedures performed and complications encountered.
Methods: A retrospective analysis of all patients who underwent resection for benign parotid PA from 2009 to 2019 in the Mater Misericordiae University Hospital, Dublin was conducted. Medical records were reviewed, with particular emphasis on clinical and histological information, including patient age and gender, tumour encapsulation, procedure performed, complications and recurrence.
Results: Fifty-four cases were included in this study. A higher frequency of cases were observed in female patients (59%), with a mean age of 47. Histological analysis revealed the majority of tumours (78%) had an intact capsule. A significant 22% of cases demonstrated a deficient capsule, with 17% described as incomplete and 5% as multifocal tumours. Superficial parotidectomy was the most commonly performed procedure (61%). 21% of these cases resulted in CN7 palsy, although 15% were House-Brackmann 3 and lower.
Conclusions: These results corroborate with previous similar studies and highlight the prevalence of capsule deficient parotid PAs. This may pose a significant risk of incomplete resection and tumour recurrence if extracapsular dissection is used inappropriately. In addition, we draw attention to the risk of CN7 palsy with superficial parotidectomy.
