Impact of facial nerve resection in parotid cancer abutting the facial nerve without preoperative paralysis: A multicentric propensity score-based analysis.

Abstract

Objectives: The management of the facial nerve (FN) is a major issue in parotid cancer, especially when there is no preoperative facial palsy and FN invasion is discovered intraoperatively. The aim of this study was to assess the impact of FN resection in patients with parotid cancer abutting the FN, without pretreatment facial palsy, using a propensity score matching.

Materials and methods: Data from all patients treated between 2009 and 2020 for a primary parotid cancer abutting or invading the FN but without pretreatment facial palsy were extracted from the national multicentric REFCOR database. Three different definitions of tumors abutting the FN were used for sensitivity analyses, in a retrospective setting. Propensity score matching was used to assess the impact of FN resection on disease-free survival (DFS), overall survival (OS) and locoregional recurrence-free survival (LRRFS).

Results: A total of 163 patients with parotid cancer abutting or invading the FN without pretreatment facial palsy were included. Among them, 99 patients (61 %) underwent FN resection. After overlap weighting and multiple imputation, no benefit of FN resection over preservation was found in terms of OS (HR = 1.21, p = 0.6), DFS (HR = 0.88, p = 0.5) and LRRFS (HR = 0.99, p = 1). Sensitivity analyses revealed similar results, and no significant efficacy was found in the subgroup analyses.

Conclusion: In this retrospective study with propensity score analysis, FN resection did not improve survival outcomes in patients without preoperative facial palsy treated surgically for a primary parotid cancer abutting the FN. In line with recent guidelines, the results of this study suggest that FN preservation should be considered whenever possible in this specific group of patients.