Oncological and functional results after the surgical treatment of parotid cancer

Outcome evaluation using an artificial intelligence-based facial measurement software for facial nerve grafting in head and neck and skull base surgery

BACKGROUND

Interposition nerve grafting is an indispensable technique for facial nerve reconstruction in head and neck, and skull base surgery. The prognostic factors are inconclusive, partly due to limited objective assessment systems for facial nerve function. This study aimed to apply an artificial intelligence (AI)-based facial asymmetry measurement system to assess facial nerve grafting outcomes.

METHODS

We retrospectively reviewed data of 23 patients who underwent facial nerve grafting between 2011 and 2020. Oral asymmetry and synkinesis severity were measured using AI.

RESULTS

Oral movement recovered at 12-18 months postoperatively. Postoperative radiotherapy and a larger number of anastomosed distal stumps were significantly associated with poor and good final oral symmetry, respectively. Synkinesis severity was weakly correlated with the degree of oral movement recovery.

CONCLUSIONS

Oral function recovered without a strong correlation with synkinesis. Caution should be exercised in facial nerve grafting for cases with postoperative radiotherapy.

Elective neck dissection in salivary gland malignancies: Systematic review and meta-analysis

We defined the occult nodal metastasis (ONM) rate of clinical node-negative salivary gland malignancies and examined the role of elective neck dissection (END). Meta-analysis querying four databases, from inception of databases to March 25th, 2020. Fifty-one studies with 11 698 patients were included. ONM rates were 64% for salivary ductal carcinoma (SDC), 51% for undifferentiated carcinoma, 34% for carcinoma ex-pleomorphic adenoma (CXPA), 32% for adenocarcinoma not otherwise specified (ANOS), 31% for lymphoepithelial carcinoma (LE), 20% for mucoepidermoid carcinoma, 17% for acinic cell carcinoma, and 17% for adenoid cystic carcinoma. T3/T4 tumors had a 2.3 times increased risk of ONM than T1/T2 tumors. High-grade tumors had a 3.8 times increased risk of ONM than low/intermediate-grade tumors. ONM rates were exceedingly high for T3/T4, high-grade, and undifferentiated, SDC, ANOS, CXPA, and LE tumors, indicating the potential role of END.

Pretherapeutic Predictive Factors for Histological High-Grade Parotid Gland Carcinoma

OBJECTIVE

The histological grade of parotid gland carcinoma (PGC) is an important prognostic factor; however, the diagnosis prior to treatment has been challenging to make. This study aimed to investigate whether the pretreatment clinical findings, including hematological inflammatory, nutritional, and immune markers, could predict the histological grade of PGC.

STUDY DESIGN

Retrospective study.

METHODS

We retrospectively enrolled 111 patients with PGC and evaluated the correlation between histological grade and pretreatment clinical findings such as age, sex, tumor staging, facial nerve paralysis, pain or tenderness, adhesion to the surrounding tissues or tumor immobility, and hematological markers.

RESULTS

Sixty patients (54%) were diagnosed with histological high-grade PGC. Univariate analysis revealed that age, T classification, N classification, TNM stage, facial nerve paralysis, adhesion/immobility, C-reactive protein (CRP), and CRP-to-albumin ratio (CAR) were significant predictors of PGC histological grade. On multivariate analysis, high T classification (T3, 4), high N classification (≥1), and elevated CRP (≥0.22 mg/dL) were independent predictors of high-grade PGC.

CONCLUSIONS

Pretreatment T classification, N classification, and CRP are significant predictors of the histological grading of PGC. Our results are useful for treatment planning and obtaining appropriate informed consent from the patients before treatment.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Long-Term Facial Nerve Outcome in Primary Parotid Cancer Surgery: A Population-Based Analysis

OBJECTIVES/HYPOTHESIS

To determine immediate postoperative and long-term facial nerve dysfunction after parotid cancer surgery, risk factors, and the role of facial reanimation surgery.

STUDY DESIGN

Population-based long-term analysis for all new primary parotid carcinoma cases in Thuringia from 1996 to 2019.

METHODS

Data of the cancer registries of Thuringia, a federal state in Germany, were analyzed in combination with hospital-based data on facial function.

RESULTS

About 477 patients (42.3% women; median age: 68 years) were included. It was observed that 6.7% had a preoperative facial nerve dysfunction, 11.7% received a radical parotidectomy, that is, that 5% had a normal preoperative facial function but needed radical surgery because of intraoperative detection of tumor infiltration into the facial nerve. About 10.2% received facial nerve reconstruction surgery. Immediate postoperative facial nerve dysfunction in the other patients was observed in 34.4% of the patients. Advanced T classification (odds ratio [OR] = 2.140; confidence interval [CI] = 1.268-3.611; P = .004) and neck dissection (OR = 2.012; CI = 1.027-3.940; P = .041) were independent risk factors for immediate postoperative facial nerve dysfunction. In addition, 22.0% showed no recovery during follow-up. Advanced T classification (OR = 2.177; CI = 1.147-4.133; P = .017) and postoperative radiotherapy (OR = 2.695; CI = 1.244-5.841; P = .012) were independent risk factors for permanent postoperative facial nerve dysfunction.

CONCLUSION

Patients with primary parotid cancer are at high risk for long-term facial nerve dysfunction. It seems that the possibilities of facial reanimation surgery needs to be utilized even more effectively.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Management of Salivary Gland Malignancy: ASCO Guideline

PURPOSE

To provide evidence-based recommendations for practicing physicians and other healthcare providers on the management of salivary gland malignancy.

METHODS

ASCO convened an Expert Panel of medical oncology, surgical oncology, radiation oncology, neuroradiology, pathology, and patient advocacy experts to conduct a literature search, which included systematic reviews, meta-analyses, randomized controlled trials, and prospective and retrospective comparative observational studies published from 2000 through 2020. Outcomes of interest included survival, diagnostic accuracy, disease recurrence, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 293 relevant studies to inform the evidence base for this guideline. Six main clinical questions were addressed, which included subquestions on preoperative evaluations, surgical diagnostic and therapeutic procedures, appropriate radiotherapy techniques, the role of systemic therapy, and follow-up evaluations.

RECOMMENDATIONS

When possible, evidence-based recommendations were developed to address the diagnosis and appropriate preoperative evaluations for patients with a salivary gland malignancy, therapeutic procedures, and appropriate treatment options in various salivary gland histologies.Additional information is available at www.asco.org/head-neck-cancer-guidelines.

Clinical Outcome of Parotidectomy with Reconstruction: Experience of a Regional Head and Neck Cancer Unit

BACKGROUND

Salivary gland pathologies represent a histologically diverse group of benign and malignant neoplasms. Currently, World Health Organization recognizes 13 benign and 24 malignant variants of all salivary gland neoplasms. Surgery continues to remain the main-stay for treatment of parotid gland neoplasms. The aim of this study was to document our experiences of the patients treated for parotid tumors and find out if any compelling variable predicted the relative clinical outcomes.

MATERIALS AND METHODS

This was a retrospective study, from records of parotidectomies performed at the operating theatre by the head and neck cancer division of the study institution between 2010 and 2013. Eligibility for study inclusion included cases with benign or malignant parotid neoplasms requiring surgical management with or without adjunct radiotherapy. The predictors of postoperative complications, overall survival (OS), and disease-free survival (DFS) were analyzed.

RESULTS

A total of 20 patients underwent parotidectomy. The mean age was 42 years. Tumors were located on the left parotid in 13 cases (65%) and the right parotid in 7 cases (35%). The surgical procedures comprised 16 superficial parotidectomies, 1 total parotidectomy, and 3 radical parotidectomy (inclusive of facial nerve sacrifice) and 2 neck dissections levels II-V. The reconstructive procedures were 2 facial nerve branch cable grafts, 1 end-to-end facial-facial nerve branch anastomoses, and 2 facial re-animation surgeries (temporalis muscle suspensions). A total of five cases (33.3%) had postoperative complications. 2 variables (length of surgery and neck dissection) were found to have an impact on postoperative complications that were statistically significant. Additionally, length of surgery was a significant predictor on the 2 years OS and DFS.

CONCLUSION

The result of this study showed good clinical outcome, especially in the benign cases. The comprehensive clinical outcome of the malignant cases could not be objectively assessed, as the OS and DFS were 50% at 2-years follow-up. It is our submission that a larger sample size is utilized in subsequent studies and quality of life evaluation is included in the methodology.

Reconstruction of facial nerve after radical parotidectomy

CONCLUSION

Most patients benefitted from immediate facial nerve grafting after radical parotidectomy. Even weak movement is valuable and can be augmented with secondary static operations. Post-operative radiotherapy does not seem to affect the final outcome of facial function.

OBJECTIVES

During radical parotidectomy, the sacrifice of the facial nerve results in severe disfigurement of the face. Data on the principles and outcome of facial nerve reconstruction and reanimation after radical parotidectomy are limited and no consensus exists on the best practice.

METHOD

This study retrospectively reviewed all patients having undergone radical parotidectomy and immediate facial nerve reconstruction with a free, non-vascularized nerve graft at the Helsinki University Hospital, Helsinki, Finland during the years 1990-2010. There were 31 patients (18 male; mean age = 54.7 years; range = 30-82) and 23 of them had a sufficient follow-up time.

RESULTS

Facial nerve function recovery was seen in 18 (78%) of the 23 patients with a minimum of 2-year follow-up and adequate reporting available. Only slight facial movement was observed in five (22%), moderate or good movement in nine (39%), and excellent movement in four (17%) patients. Twenty-two (74%) patients received post-operative radiotherapy and 16 (70%) of them had some recovery of facial nerve function. Nineteen (61%) patients needed secondary static reanimation of the face.