Risk Factors of Postoperative Facial Palsy for Benign Parotid Tumors: Outcome of 1,018 Patients

Abstract

The aim of this study was to evaluate the rate of postoperative facial palsy in benign parotid tumors, as well as its risk factors, pathology, and clinical results.Study Design: Retrospective analysis.Methods: We performed a retrospective analysis of data from patients whose initial operation for a benign parotid tumor had been performed in our department between 1999 and 2020.Results: We included 1,018 patients in this study. The most common tumor observed was pleomorphic adenoma (614 patients), followed by Warthin tumor (234 patients). Fine-needle aspiration cytology and frozen section biopsy were used to identify the tumor histopathology. The overall rate of postoperative facial nerve palsy was 19.5%; the rate was significantly higher in patients with large-diameter tumors or deep lobe tumors. Postoperative facial palsy improved within 24 months of surgery in all cases. There were no cases with permanent facial palsy.Conclusions: Postoperative facial nerve palsy developed regularly after surgery to remove benign parotid tumors despite preservation of the nerve. Palsy rate was high in patients with large tumors or deep lobe tumors. Despite the high risk of facial palsy in these patients and the benign nature of the tumor, we recommend surgery rather than follow-up observation, as the risk of postoperative facial palsy may increase as the tumor grows. It is important to provide an accurate explanation on the risks of postoperative complications to all patients to obtain appropriate informed consent for surgery.

A retrospective study of parotid gland tumors at a single institution

“…The goal of surgical management of benign parotid tumors is to completely remove the tumor and preserve the facial nerve ( 6 ). Partial superficial parotidectomy was characterized by the preservation of part of the unaffected parotid tissue and the dissection of a smaller area of facial nerve branches ( 6 ). Partial superficial parotidectomy was associated with fewer complications and lower recurrence rates than superficial parotidectomy ( 35 , 36 ).…”

“…In the present study, recurrence after partial superficial parotidectomy was observed in only 1 patient (2%) with pleomorphic adenoma. Even if the facial nerve is completely preserved, a certain rate of postoperative facial nerve palsy is inevitable ( 6 ). The incidence of transient facial nerve palsy after parotidectomy for benign parotid tumors ranges from 10–65%, with persistent palsy seen in <5% of cases ( 37 – 39 ).…”

“…Surgery for benign parotid tumors was performed by partial superficial parotidectomy ( 6 ). Briefly, after a preauricular to postauricular (modified Blair incision) S-shaped incision, the trunk of the facial nerve was identified by intraoperative FNM with 1.0 mA of stimulation (NIM-Response 3.0 system, Medtronic Inc., Jacksonville, FL).…”

In Reference to Risk Factors of Postoperative Facial Palsy for Benign Parotid Tumors: Outcome of 1,018 Patients

“…We read the article "Risk Factors of Postoperative Facial Palsy for Benign Parotid Tumors: Outcome of 1,018 Patients" by Ryo Kawata et al with great interest and would like to congratulate the authors on their excellent work in attempting to highlight the possible risk factors for facial palsy after parotid surgery for benign tumors. 1 However, there are a few questions that we would like to have clarified in order to gain a better understanding of the study.…”

In Response to Risk Factors of Postoperative Facial Palsy for Benign Parotid Tumors: Outcome of 1,018 Patients

“…This study investigated patients who underwent partial parotidectomy. 1 In most patients, the facial nerve is identified by anterograde approach (AA). In rare cases, a tumor is located just above the superficial layer of the main trunk is dissected the facial nerve by retrograde approach (RA).…”