An objective assessment of proximal and distal facial nerve exploration during superficial parotidectomy

A Review of the Current Literature on Pleomorphic Adenoma

Pleomorphic adenomas (PA) are the most common benign salivary gland tumors. They arise from the major salivary glands, as well as the minor salivary glands. They may arise rarely from the palate, oral cavity, neck, and nasal cavity also. Yet, the fourth, fifth, and sixth decades of life are the most common for them to manifest. Forty percent of them occur in males and 60% in females. It is a benign mixed tumor, which has three components: an epithelial component, a myoepithelial cell component, and a mesenchymal component. A fibrous capsule separates these cells from the surrounding tissues. It generally presents as a slowly progressing painless swelling, which is well-delineated, nonsymptomatic, and not involving the facial nerve. Salivary gland tumors can be accurately diagnosed before surgery using fine-needle aspiration (FNA), ultrasonography (USG), and computed tomography (CT) scan. Calponin, cluster of differentiation 9 (CD9), glial fibrillary acidic protein (GFAP), Mcl-2, metastasis suppressor gene (NM23), p63, S-100, smooth muscle actin (SMA), and SRY-box transcription factor 10 (SOX10) exhibit the majority of the positive reactions in pleomorphic adenomas. The diagnostic marker pleomorphic adenoma gene 1 (PLAG1) is frequently employed since it is specific for pleomorphic adenoma. Although benign, these epithelial tumors have a propensity to recur and undergo malignant transformation if incompletely excised, leading to increased morbidity in these patients. A review of the consensus guidelines and literature was conducted, and the online literature on the subject from 2002 was included. This article is not a complete review of all the available literature; rather, it is a comprehensive review of the topic.

Antegrade versus retrograde facial nerve dissection in benign parotid surgery: Is there a difference in postoperative outcomes? A meta-analysis

OBJECTIVE

The primary aim of this meta-analysis was to test the null hypothesis of no difference in facial nerve dysfunction in studies that compared classical antegrade facial nerve dissection (AFND) versus retrograde facial nerve dissection (RFND) during benign parotid surgery.

METHODS

A comprehensive search of PubMed, the Cochrane Central Register of Controlled Trials, Scopus, Google Scholar, Science Direct and relevant journals was undertaken up to June 27, 2018. Randomized controlled clinical trials (RCTs), controlled clinical trials (CCTs), and retrospective studies aimed at comparing the effect of AFND vs. RFND during parotidectomy were included. The outcome measures included facial nerve dysfunction, Frey's syndrome, recurrence, silaocele, salivary fistula, operating time length of hospital stay, and estimated blood loss. Pooled risk ratio (RR) and weighted mean differences (MD) with 95% confidence intervals were calculated using either a fixed-effects or random-effects model.

RESULTS

Ten studies; four RCTs and five retrospective studies were included. There were 570 patients (319 in RFND group and 251 in AFND group). 481 patients in 9 studies reported the incidence rate of facial nerve dysfunction. No statistical significant difference was observed between both groups concerning the occurrence of transient or permanent facial nerve paralysis (p = 0.44 and 0.11 respectively). One out 10 studies reported the incidence rate of sialocele, however no statistical difference was observed between the two techniques. There was reduction in the operative time (19.30 min), amount of blood loss (25.08 ml) and amount of healthy salivary tissues removed (12.20 mm) in RFND compared with AFND.

CONCLUSIONS

According to the results of the current review there is no evidence demonstrating a significant advantage of one approach over another, therefore, well-designed standardized RCTs are required.