Investigation of Parotid Cancer Cases Diagnosed as Bell's Palsy at Initial Presentation: The 23 Year Experience of a Single Institution

Objective: Facial nerve paralysis due to parotid carcinoma is sometimes misdiagnosed as Bell's palsy. This study aimed to compare patients with parotid carcinoma with and without accompanying facial nerve paralysis and to capture the features of patients misdiagnosed with Bell's palsy. Methods: Among 209 patients, 42 (20%) had facial nerve paralysis. Of these 42 patients, 14 had received treatment for facial nerve paralysis without being diagnosed with parotid carcinoma (pretreatment group); the remaining 28 patients had not received any pretreatment and were diagnosed with parotid carcinoma at the initial visit to our hospital (no pretreatment group). This study compared patients with and without facial nerve paralysis and the pretreatment and no pretreatment groups. Results: The 42 patients with facial nerve paralysis had a significantly higher frequency of pain/tenderness and adhesion with surrounding tissues, significantly higher proportions of deep lobe tumors, and a significantly higher proportion of high-grade malignancy. In addition, the disease-specific and disease-free 5 year survival rates were significantly poorer in patients with than in those without facial nerve paralysis. The comparison between the pretreatment and no pretreatment groups revealed no significant differences in any factors nor survival rate. Five patients in the pretreatment group complained of palpable masses or pain/tenderness at the time of their initial treatment for paralysis. Conclusion: Patients with parotid carcinoma who present with facial nerve paralysis at the initial visit have a significantly poorer prognosis. The number of cases in the pretreatment group can be reduced by performing a detailed examination, which can potentially improve the prognosis.

Influence of parotid lymph node metastasis on distant metastasis in parotid gland cancer

Background

The aim of this study was to analyze the impact of the number and extranodal extension (ENE) of positive parotid lymph nodes (LNs) on distant metastasis in parotid cancer.

Methods

Patients with surgically treated parotid cancer were retrospectively enrolled. The hazard ratios (HRs) of the number and ENE of positive parotid LNs on distant metastasis-free survival (DMFS) were evaluated.

Results

In the Cox model, the groups with zero and one positive LN had comparable 10-year DMFS, but those with two positive LNs had an HR of 2.11 (95% CI: 1.36-5.29), and those with three or more positive LNs had an HR of 3.31 (95% CI: 2.05-8.43). The presence of ENE in parotid LNs did not impact the DMFS (p = 0.462; HR: 2.17; 95% CI: 0.84-6.17).

Conclusion

Parotid LN metastasis was associated with decreased DMFS; this effect was mainly driven by the number of positive LNs rather than ENE.

Dosimetric investigation of radiation-induced trigeminal nerve toxicity in parotid tumor patients

PURPOSE

We aimed to describe the association between trigeminal nerve (TN) dose and toxicity and determine a threshold value that leads to TN toxicity in patients with parotid tumors treated with adjuvant conventional fractionated radiation therapy.

METHODS AND MATERIALS

Eighteen patients who underwent adjuvant radiotherapy (RT) between 2013 and 2018 were included in this retrospective study. TN and its branches were outlined subsequently on the planning CT scans. The doses received by TN were obtained based on the dose-volume histogram. The dose and toxicity relationship was investigated over the total prescribed dose. RT-related toxicity was graded according to Common Terminology Criteria for Adverse Events V4.0 (CTCAEv4.0).

RESULTS

The median follow-up was 29.5 months. After RT, 61% of patients had Grade I-II late TN toxicity divided into Grade I in 4 (22%) and Grade II in 7 (39%) patients. TN injury symptoms were as follows: loss of sensation in the chin area in 3, difficulty in jaw movements in 3, and paresthesia in 5 patients. The total RT dose (p = 0.001), Dmax (p = 0.001), PTV-TN Dmax (p = 0.001), D1cc (p = 0.004), D0.5cc (p = 0.001), and D0.1cc (p = 0.01) had a significant effect on TN toxicity. Cut-off values leading to toxicity were determined as 66, 65.5, 65.25, 63.6, and 62.7 Gy for Dmax, PTV-TN Dmax, D0.1cc, D 0.5cc, and D1cc, respectively.

CONCLUSIONS

Radiation-induced TN injury in head and neck cancer patients may further be investigated in clinically prospective trials by virtue of high toxicity rates with current RT doses in our retrospectively designed dosimetric study in parotid tumors.

Number of positive lymph nodes is superior to neck stage of the 8th AJCC in predicting prognosis in parotid mucoepidermoid carcinoma

BACKGROUND

To clarify the impact of the number of positive lymph nodes (LNs) on the prognosis of parotid mucoepidermoid carcinoma (MEC).

METHODS

Patients who underwent neck dissection for parotid MEC were retrospectively enrolled. The primary outcome variable was overall survival (OS). Associations between OS and LN factors, including the AJCC N stage, intraparotid LN metastasis, number of positive LNs, LN size, and extranodal extension (ENE), were evaluated using Cox proportional hazard regression analyses.

RESULTS

A total of 720 patients were included with a mean age of 56 ± 16 years. There was no additional survival compromise until two positive LNs were presented. After adjusting for the number of positive LNs, intraparotid LN metastasis, ENE, and LN size were not related to prognosis. Our proposed N stage based on the number of metastatic LNs (0/1 vs. 2-4 vs. 5+) showed a superior C-index to the AJCC N stage in OS prediction.

CONCLUSION

Quantitative LN burden was an important determinant of prognosis, and the proposed N stage provided better OS stratification than the AJCC N stage.

Patterns of Lymph Node Metastasis in Parotid Cancer and Implications for Extent of Neck Dissection

OBJECTIVE

The role and extent of neck dissection in primary parotid cancer are controversial. Herein, we characterize patterns of lymph node metastasis in parotid cancer.

STUDY DESIGN

Retrospective analysis.

SETTING

National Cancer Database.

METHODS

Patients with the 6 most common histologic subtypes of parotid cancer were selected. Primary outcomes were the distribution of positive lymph nodes by level and overall survival assessed by Cox analysis. Secondary outcomes included predictors of extended lymph node involvement (≥3 lymph nodes or Level IV/V involvement), via logistic regression.

RESULTS

Six thousand nine hundred seventy-seven patients with acinic cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, carcinoma ex pleomorphic adenoma (CExPA), mucoepidermoid carcinoma, and salivary duct carcinoma (SDC) were included. Among cN0 patients, 8.2% of low-grade tumor patients had occult nodal metastasis versus 30.9% in high-grade tumor patients. Elective neck dissection was not associated with an overall survival benefit (adjusted hazard ratio: 1.10; 0.94-1.30, p = .238). Among cN+ tumors, CExPA (odds ratio [OR]: 1.88, 1.05-3.39, p = .034) and high-grade pathology (OR: 3.03, 1.87-4.93, p < .001) were predictive of having ≥3 pathologic nodes. CExPA (OR: 2.13, 1.22-3.72, p = .008), adenocarcinoma (OR: 1.60, 1.11-2.31, p = .013), SDC (OR: 1.92, 1.17-3.14, p < .01), and high-grade pathology (OR: 3.61, 2.19-5.97, p < .001) were predictive of Level IV/V neck involvement.

CONCLUSIONS

In parotid malignancy, nodal metastasis distribution is dependent on histology and grade. High-grade tumors and certain histologies (SDC and adenocarcinoma) had a higher incidence of occult nodes. Comprehensive neck dissection should also be considered for node-positive high-grade tumors, SDC, and adenocarcinoma.

Myoepithelial Carcinoma Arising in a Salivary Duct Cyst of the Parotid Gland: Case Presentation

Cystic lesions observed in parotid glands are relatively rare and comprise 2-5% of all parotid primaries. A salivary duct cyst (SDC) is a true cyst representing 10% of all salivary gland cysts. The risk of malignant transformation of SDC's epithelium is extremely rare. In the literature, only three cases of carcinoma ex SDC of the parotid gland are described. This report presents the first in the literature case of myoepithelial carcinoma (MECA) arising from a parotid SDC. A 75-year-old male patient was referred to the Department of Cranio-Maxillofacial Surgery of the Jagiellonian University in Cracow, Poland due to a cystic tumor arising from the right parotid gland. Superficial parotidectomy with facial nerve preservation was performed. Histological examination confirmed a rare case of MECA emerging from the SDC. The immunohistochemical profile of MECA ex SDC was presented. During 6 months of the follow-up, local recurrence or distant metastasis was not observed.

Frozen section detected perineural spread in a grossly normal nerve away from tumor changes the surgical plan in parotid cancer

Perineural spread (PNS) through the facial nerve is a well-recognized pathway of spread in parotid cancers. Negative margins in the facial nerve are important in the total extirpation of cancer. We report a case of mucoepidermoid carcinoma of the parotid which was involving only the upper temporofacial division of the facial nerve at the periphery clinically and per-operatively. The upper trunk was divided at about 3cm away from the tumor at its junction with the lower trunk and the nerve was grossly normal. To our surprise disease was extending at this distance as a PNS in the frozen section analysis. This unexpected finding made the resection margin positive and we had to sacrifice the main trunk of the facial nerve as back as possible in the parotidectomy field for a negative margin in the nerve which was confirmed with frozen section again. The case emphasizes the importance of microscopic margin assessment of facial nerve in parotid cancers with the involvement of nerve at branches, even if imaging is negative or gross disease is not seen at the cut end or distant from the tumor-involved area.

Preoperative Magnetic Resonance Image and Computerized Tomography Findings Predictive of Facial Nerve Invasion in Patients with Parotid Cancer without Preoperative Facial Weakness-A Retrospective Observational Study

Simple Summary

Facial nerve invasion in parotid cancer affects survival outcomes as well as functional outcomes after surgery-based treatment. Normal facial muscle function before surgery does not always exclude the possibility of involvement of the facial nerve by a tumor. Especially in patients without facial palsy, accurate evaluation of invasion before surgery is necessary to plan optimal facial nerve resection and reconstruction. Various findings are obtained from preoperative radiological findings, such as CT and MRI. We evaluated the role of these radiological findings in predicting nerve invasion. Large tumor, spiculated margin, and anterolateral location may suggest a high risk of nerve involvement even in patients with normal preoperative facial function. These findings may help surgeons to avoid unexpected facial nerve invasion and to make adequate surgical plans to get optimal oncological and functional outcomes.

Abstract

(1) Background: Facial nerve resection with reconstruction helps achieve optimal outcomes in the treatment of facial nerve invasion (FNI) of parotid cancer. Preoperative imaging is crucial to predict facial nerve reconstruction. The radiological findings of CT or MRI may predict FNI in the parotid cancer even without facial paralysis. Methods: We retrospectively reviewed the records of 151 patients without facial nerve paralysis before surgery who had undergone tumor resection. Previously untreated parotid cancers were included. (2) Results: The median follow-up duration was 62 months (range: 24–120 months). The FNI (+) group (n = 30) showed a significantly worse 5-year overall survival compared with the FNI (−) group (75.5 vs. 93.9%; hazard ratio = 4.19; 95% confidence interval: 1.74–10.08; p = 0.001). The tumor margin, tumor size, presence in the anterolateral parotid region (area 3), retromandibular vein involvement, distance from the stylomastoid foramen to the upper tumor margin, and a high tumor grade were significant factors related to FNI in the univariate analysis. A spiculated tumor margin, the tumor size (2.2 cm), and presence in area 3 were factors predicting FNI in the logistic regression model (p = 0.020, 0.005, and 0.050, respectively; odds ratio: 4.02, 6.40, and 8.16, respectively). (3) Conclusions: The tumor size (≥2.2 cm), spiculated margin, and presence in area 3 as presented in CT and MRI may help clinicians preoperatively predict FNI in patients with parotid cancer and establish an appropriate surgical plan.

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.

Nomogram Predicting Cancer-Specific Death in Parotid Carcinoma: a Competing Risk Analysis

Purpose

Multiple factors have been shown to be tied to the prognosis of individuals with parotid cancer (PC); however, there are limited numbers of reliable as well as straightforward tools available for clinical estimation of individualized mortality. Here, a competing risk nomogram was established to assess the risk of cancer-specific deaths (CSD) in individuals with PC.

Methods

Data of PC patients analyzed in this work were retrieved from the Surveillance, Epidemiology, and End Results (SEER) data repository and the First Affiliated Hospital of Nanchang University (China). Univariate Lasso regression coupled with multivariate Cox assessments were adopted to explore the predictive factors influencing CSD. The cumulative incidence function (CIF) coupled with the Fine-Gray proportional hazards model was employed to determine the risk indicators tied to CSD as per the univariate, as well as multivariate analyses conducted in the R software. Finally, we created and validated a nomogram to forecast the 3- and 5-year CSD likelihood.

Results

Overall, 1,467 PC patients were identified from the SEER data repository, with the 3- and 5-year CSD CIF after diagnosis being 21.4% and 24.1%, respectively. The univariate along with the Lasso regression data revealed that nine independent risk factors were tied to CSD in the test dataset (n = 1,035) retrieved from the SEER data repository. Additionally, multivariate data of Fine-Gray proportional subdistribution hazards model illustrated that N stage, Age, T stage, Histologic, M stage, grade, surgery, and radiation were independent risk factors influencing CSD in an individual with PC in the test dataset (p < 0.05). Based on optimization performed using the Bayesian information criterion (BIC), six variables were incorporated in the prognostic nomogram. In the internal SEER data repository verification dataset (n = 432) and the external medical center verification dataset (n = 473), our nomogram was well calibrated and exhibited considerable estimation efficiency.

Conclusion

The competing risk nomogram presented here can be used for assessing cancer-specific mortality in PC patients.

Synchronous Resection of Parotid Metastasis With Esophagectomy: A Case Report

BACKGROUND

Preoperative diagnosis of parotid tumor is mainly performed via imaging and cytology to avoid both facial nerve injury and tumor seeding. Synchronous resection of solitary parotid metastasis with esophagectomy for esophageal squamous cell carcinoma is rarely performed.

CASE REPORT

This is a case report of a 58-year-old male patient with a left preauricular tumor, which was cytologically diagnosed as squamous cell carcinoma. Esophageal squamous cell carcinoma was pathologically diagnosed following ¹⁸F-fluorodeoxyglucose positron emission tomography with computed tomography. His diagnosis was cT2N0M0 esophageal squamous cell carcinoma with cT3N0M0 parotid carcinoma. Esophagectomy for esophageal cancer, as well as parotidectomy were performed. Pathological diagnosis of pT1bN1M1 (parotid) esophageal squamous cell carcinoma was based on exclusion diagnosis of no primary tumor from several specialists and pathological findings including immunohistochemical staining.

CONCLUSION

Reporting of more cases of rare synchronous metastasectomy and esophagectomy is needed to clarify treatment strategies.

The significance of regional metastasis location in head and neck cutaneous squamous cell carcinoma

BACKGROUND

Regional metastasis of head and neck cutaneous squamous cell carcinoma (HNcSCC) can be seen in either parotid and/or cervical lymph nodes. The aim of this study was to assess whether there was a difference in prognosis between parotid and cervical nodal metastases.

METHODS

Patients with regional metastasis from HNcSCC were identified from an institutional database. Disease-specific (DSS) and overall survival (OS) were calculated using the Kaplan-Meier method and Cox proportional hazards models.

RESULTS

Five hundred and thirty-five patients were identified with median follow-up of 26.4 months (3-255 months). Two hundred and thirty-five patients had parotid metastasis, 96 patients had neck metastasis, and 204 patients had both. On multivariable analysis, any regional metastasis to the neck when compared to parotid alone conferred worse DSS (HR 1.8, p = 0.007) and OS (HR 1.3, p = 0.024).

CONCLUSION

Regional metastasis of HNcSCC to the neck confers worse outcomes compared to metastasis to the parotid alone.

A case of metachronous bilateral secretory carcinoma

Secretory carcinoma (SC) was first recognized as a distinct salivary malignancy in 2010. In the nine years since its recognition, there have been multiple reports of SC of the major and minor salivary glands, as well one case of tongue base involvement. Here we present the first reported case of bilateral SC. The first tumor, diagnosed before the recognition of SC, was classified as mucoepidermoid carcinoma. After the contralateral parotid tumor was diagnosed as SC in 2016, the two histologies were compared, and the mucoepidermoid carcinoma was reclassified as SC. In this report, we describe our patient’s clinical course and review the SC literature, with a focus on pathologic diagnosis and clinical prognosis.

Controversies in the Workup and Surgical Management of Parotid Neoplasms

OBJECTIVE

Parotid neoplasms are a rare heterogeneous group of tumors with varied clinical presentation and behavior. Here we provide an evidence-based review of the contemporary approach to evaluation and surgical management of parotid tumors.

DATA SOURCE

PubMed and Web of Science Databases.

REVIEW METHODS

Searches of the PubMed and Web of Science databases were performed on subjects related to the diagnosis and surgical management of parotid neoplasms. Particular emphasis was placed on the following areas: evaluation of parotid tumors, including imaging workup and the utility of fine-needle aspiration; extent of surgery of the primary lesion, including the extent of parotidectomy as well as oncologic management of the facial nerve; the extent of surgery of involved and at-risk cervical lymphatics; and parotid bed reconstruction. Articles published from 2014 to the present were prioritized, supplementing with information from prior studies in areas where data are lacking.

CONCLUSION

A summary of the literature in these areas is outlined to provide an evidence-based approach to evaluation and management of parotid neoplasms.

IMPLICATIONS FOR PRACTICE

While data are available to help guide many aspects of workup and management of parotid neoplasms, further research is needed to refine protocols for this heterogeneous group of diseases.

Incidence and survival trends of parotid malignancies over 42 years

BACKGROUND

There is a paucity of information regarding the incidence and survival of parotid malignancies over time.

METHODS

The Surveillance, Epidemiology, and End Results population-based cancer registry was queried for parotid malignancies from 1973 to 2015.

RESULTS

The age-adjusted incidence of parotid malignancies has increased by 58.1% (7.87-12.44 per 1 000 000). Analysis of histologic type revealed an increased annual percent change (APC) of acinar cell carcinoma (1.38) and squamous cell carcinoma (1.58), but decreased APC of adenoid cystic carcinoma (-1.63) and adenocarcinoma NOS (-0.86) (P < .05). The disease-specific survival of mucoepidermoid carcinoma, adenocarcinoma NOS, and squamous cell carcinoma significantly improved (P < .05) over time.

CONCLUSION

The incidence of parotid cancer is rising steadily since 1973, while the incidence of overall head and neck cancer has decreased. Further research is necessary to understand the etiology, risk factors, and pathophysiology of parotid cancer to curb its rising incidence.

LEVEL OF EVIDENCE

4.

Real impact of surgical robotic system for precision surgery of parotidectomy: retroauricular parotidectomy using da Vinci surgical system

Background

We performed robotic parotidectomy with or without robotic neck dissection via a retroauricular approach in patients with parotid benign and malignant tumors and analyzed treatment outcomes of the patients to evaluate the safety and feasibility of robotic parotidectomy.

Methods

Between January 2017 and July 2018, 53 patients received robotic parotidectomy with/without robotic neck dissection through a remote access retroauricular incision without a preauricular incision.

Results

All operations were successfully performed in all patients without significant perioperative complications or tumor spillage. Tumors were located in the superficial lobe of the parotid gland in 40 patients, and the remaining 13 tumors were located in the deep lobe of the parotid gland. Postoperative pathologic examination revealed benign tumor in 32 patients and malignant tumors in 18 patients. The mean operation time was 226 minutes in patients who underwent only parotidectomy and 375 minutes in patients who underwent parotidectomy with robotic neck dissection. The average amount of bleeding was 23 mL, and the amount of drainage after operation averaged 171 mL. The average length of hospital stay was 6 days. Postoperative complications were limited to transient facial paralysis in three patients, all of which resolved within 1 month. All patients were satisfied with their cosmetic results at 6 months after operation.

Conclusions

Robotic parotidectomy with/without robotic neck dissection through a retroauricular approach was a feasible and safe technique in patients with parotid benign and malignant tumor. Specifically, we found it to be helpful in young patients with malignant parotid tumors who should receive cervical lymphadenectomy and parotidectomy, because it does not leave a visible scar on the face or neck. In the future, long-term follow-up will be necessary to validate its oncologic safety and functional outcomes.

The Role of Prognostic Factors in Salivary Gland Tumors Treated by Surgery and Adjuvant Radio- or Chemoradiotherapy - A Single Institution Experience

Purpose

Salivary gland neoplasms are rare cancers of the head and neck region. Radical treatment in tumors of large salivary glands is surgery. Adjuvant treatment depends on the presence of risk factors that worsen the prognosis, but the role of these factors in patients treated by surgery with radio- or radiochemotherapy still remains unclear. The aim of the study is assessment of treatment results and identification of the risk factors affecting the prognosis in patients with tumors of large salivary glands subjected to adjuvant radio- or radiochemotherapy.

Patients and Methods

The study included 126 patients with local stage large salivary gland cancer who were treated surgically with adjuvant radio- or radiochemotherapy. The study excluded inoperable patients, patients with distant metastases, patients in a poor general condition and patients with contraindications to adjuvant treatment. They were treated between 2006 and 2016 and evaluated in terms of OS (overall survival), CSS (cancer-specific survival), RFS (relapse-free survival) and LRFS (local relapse-free survival).

Results

During a 44-month follow-up, 5-OS, CSS, RFS and LRFS were 55%, 68%, 60% and 73%, respectively. Multivariate analysis showed that OS was influenced by the following parameters: WHO performance status, TNM stage (T and N parameters), radicality of surgery, histopathological type, applied method of radiotherapy planning and tumor volume. WHO performance status, T and N parameters of the TNM stage and large volume of elective area influenced CSS, and the T parameter of the TNM stage, the dose below 60Gy and tumor volume influenced RFS and LRFS. Chemoradiotherapy can be used in N-positive patients.

Conclusion

The analysis indicates that the TNM grade, histopathological type, patient’s condition, radicality of the procedure, technique and dose of radiotherapy are the most important prognostic factors in these patients.

Preoperative biopsy in parotid malignancies: Variation in use and impact on surgical margins

OBJECTIVES

Determine rate of preoperative biopsy in parotid malignancies, identify factors associated with its use, and its association with surgical margins.

STUDY DESIGN

Retrospective cohort.

SETTING

Commission on Cancer-Accredited Institutions.

SUBJECTS AND METHODS

We included 5533 patients treated surgically for a parotid malignancy 2004-2014 in the National Cancer Database. Chi-squared tests, univariable, and multivariable logistic regressions were used to evaluate predictors of preoperative biopsy (defined as needle, aspiration, or incisional), and associate biopsy with surgical margins.

RESULTS

Preoperative biopsy was utilized in 26.0% of patients. Biopsy was more likely in patients >60 years (odds ratio [OR]: 1.19, P = .035), advanced clinical T stage (vs. T1,T2 OR: 1.23, P = .009; T3 OR: 1.26, P = .026; T4A OR: 2.05, P < .001), advanced clinical N stage (vs. N0, N1: OR: 1.39, P = .013; N2/3: OR: 1.63, P < .001), in academic centers (OR: 1.18, P < .024), and in higher volume centers (vs. low, medium OR: 1.28, P = .002; high OR: 2.16, P < .001). Biopsy use increased over time (vs. 2004-2006, 2007-2010 OR: 1.20, P = .047; 2011-2014 OR: 1.39, P < .001). Biopsy was associated with a reduced risk of positive margins in patients with clinical T1 stage (OR: 0.70, P = .012), and younger than 61 (OR: 0.79, P = .036).

CONCLUSION

The national rate of preoperative biopsy in parotid malignancy is low at 26.0%, but has increased over time. Preoperative biopsy is associated with a reduced risk of positive margins in younger patients and those with early clinical stage, suggesting its increased use may improve surgical outcomes and decrease reoperation or adjuvant therapy in these subgroups of patients.

LEVEL OF EVIDENCE

3 Laryngoscope, 130:1450-1458, 2020.

A nomogram to estimate the risk of developing distant metastases in parotid cancer

BACKGROUND

Parotid cancer (PC) is a heterogeneous group of malignant tumors whose management mainly focuses on locoregional control. However, distant metastases (DM) can represent the most common cause of treatment failure. We have defined the predictors and developed a model that can predict a single patient's risk to develop DM.

METHODS

We have analyzed our institutional database of 259 patients with PC and use it to develop a nomogram. C-index and calibration curves were used to assess performance of our model.

RESULTS

DM appeared in 18.9% of patients. Age, cT, pN, perineural invasion, and adenoid cystic carcinoma were significantly associated with distant failure.

CONCLUSIONS

We here present the first model to identify patients with PC at high risk of DM. Such tool can be of great value in managing these rare cancers in terms of a more precise prognosis and follow-up while waiting for better systemic therapies to come in the future.

Role of the pretreatment neutrophil-to-lymphocyte ratio in the survival of primary parotid cancer patients

BACKGROUND

To analyze the value of the pretreatment neutrophil-to-lymphocyte ratio (NLR) in the survival of patients with parotid cancer.

METHODS

In total, 249 patients were enrolled. Information including age, sex, pretreatment NLR, and pathologic variables such as, tumor stage, intraparotid node (IPN) metastasis, and follow-up findings was extracted and analyzed.

RESULTS

IPN metastasis was noted in 45 (18.1%) patients, and the mean NLR was 2.48, with a range from 1.5 to 6.1. The NLR was significantly associated with tumor stage, disease stage, and disease grade. A total of 73 patients died of the disease, and the 10 -year disease-specific survival (DSS) rate was 62%. In patients with an NLR<2.48, the 10 -year DSS rate was 68%; in patients with an NLR≥2.48, the 10 -year DSS rate was 58%, and the difference was significant (P=0.006). Cox model analysis showed that the NLR was an independent prognostic factor for DSS.

CONCLUSION

The long-term survival of primary parotid cancer patients is relatively favorable, and the pretreatment NLR is significantly associated with prognosis.

Oncologic outcome of parotid mucoepidermoid carcinoma in pediatric patients

Background

The goal of this study was to investigate the long-term oncologic outcome of parotid mucoepidermoid carcinoma (MEC) in pediatric patients.

Patients and methods

Patients <19 years old who were diagnosed with MEC from January 1990 to December 2017 were retrospectively enrolled in this study. The main analyzed indexes included intraparotid node (IPN) metastasis, neutrophil-tolymphocyte ratio (NLR), loco-regional control (LRC), and disease-specific survival (DSS) rates.

Results

A total of 73 patients were enrolled. IPN metastasis occurred in 13 (17.8%) patients; the mean value of the NLR was 2.48 (range: 1.3–6.1). Loco-regional recurrence occurred in 12 patients, and 7 patients died of the disease. The 10-year LRC and DSS rates were 83% and 88%, respectively. IPN metastasis remained significantly related to recurrence in both univariate and Cox model analyses; a high NLR was significantly associated with recurrence in the univariate analysis but not in the Cox model. IPN metastasis remained significantly related to disease-related death in both the univariate and Cox model analyses; a high NLR was not associated with the DSS in univariate analysis.

Conclusion

The long-term survival rate was relatively favorable in pediatric MEC. IPN metastasis was an independent risk factor for loco-regional recurrence and DSS. The role of the NLR in predicting survival in parotid cancer requires more research.

Prognostic Value of the Pretreatment Neutrophil-to-Lymphocyte Ratio in Pediatric Parotid Cancer

Objective: Our goal was to evaluate the prognostic significance of the neutrophil-to-lymphocyte ratio (NLR) in pediatric patients with parotid cancer. Materials and Methods: Pediatric patients with primary parotid cancer were retrospectively enrolled from several clinical centers. The associations between the clinical-pathologic variables and NLR and the prognostic significance of NLR for recurrence-free survival (RFS) and disease-specific survival (DSS) were analyzed. Results: A total of 123 patients were included. The mean NLR was 2.51 and ranged from 1.7 to 6.1. The tumor stage and disease grade were significantly related to NLR. In patients with NLR < 2.51, the 10-year RFS rate was 97%, and in patients with NLR ≥ 2.51, the 10-year RFS rate was 84%; the difference was significant (p = 0.016). In patients with NLR < 2.51, the 10-year DSS rate was 98%, and in patients with NLR ≥ 2.51, the 10-year DSS rate was 83%; this difference was also significant (p = 0.035). Further Cox model analysis confirmed the independence of NLR in predicting the RFS and DSS rates. Conclusions: NLR is significantly associated with prognosis in pediatric patients with parotid cancer.

Acinic cell carcinoma of parotid gland with cavernous sinus metastasis: A case report

Acinic cell carcinoma (AciCC) is a low-grade malignancy which rarely metastasizes to bone or cavernous sinuses. A 62-year-old male patient, previously treated for AciCC of right parotid with surgery and local radiotherapy, presented 10 years later with progressive visual impairment and restriction of ocular movements. Magnetic resonance imaging of the head and orbit showed an expansile lobulated mass with heterogeneous signal intensity in bilateral cavernous sinus with encasement of the internal carotid artery on both sides. Fluorodeoxyglucose positron emission tomography/computed tomography showed multiple lytic lesions with increased uptake in the left clavicle (with soft tissue component), sternum, multiple cervico-dorso-lumbar vertebrae, and ribs. Biopsy from the clavicular lesion showed AciCC. He was treated with palliative radiotherapy to cavernous sinuses and other metastatic site followed by palliative chemotherapy with six cycles of paclitaxel and carboplatin. He had a partial response to palliative treatment and had good symptomatic relief at 12 months of follow-up.

Management and prognosis of cancers in the accessory parotid gland

OBJECTIVE

This study was performed to analyze the clinical management of accessory parotid gland (APG) cancer and possible risk factors for disease-related death.

METHODS

Patients diagnosed with primary APG cancers in the largest medical center in Northeast China were enrolled from January 1990 to December 2016.

RESULTS

All 43 patients underwent resection of the tumors and superficial parotid gland by a standard Blair incision. Seven (16.3%) patients also required selective neck dissection. The most common lesion was mucoepidermoid carcinoma. Temporary facial paralysis occurred in 11 (25.6%) patients, and permanent facial paralysis occurred in 3 (7.0%) patients because of surgical resection of the facial nerve, which was involved with the tumor. The 5- and 10-year disease-specific survival rates were 86.0% and 66.0%, respectively. The tumor stage, neck status, neck dissection, and tumor grade were significantly associated with disease-related death, but only the tumor grade was an independent risk factor.

CONCLUSION

Superficial parotidectomy is a reliable surgical procedure associated with a high survival rate and low morbidity in treating APG cancers. The tumor grade is the key prognostic factor.

Sarcomatoid Carcinoma in the Parotid Gland: A Review of 30 Years of Experience

OBJECTIVE

The goal of this study was to analyze the results of clinical treatment of sarcomatoid carcinoma in the parotid gland by reviewing 30 years of experience.

METHODS

Thirty-five patients were enrolled in this study. The Kaplan-Meier methods were used to calculate the recurrence-free survival (RFS) and disease-specific survival (DSS) rates. The Cox model was used to determine the independent risk factor.

RESULTS

Mean age at presentation was 57.8 years, and most of the patients were staged as tumor (T)3 or T4. Perineural invasion was noted in 15 (42.9%) patients. Fifteen (42.9%) patients received neck dissection due to clinically suspicious nodes. Of those, three patients had pathologically positive nodes. Recurrence was noted in 14 patients; the most common pattern of treatment failure was local recurrence, and only 40% of the patients could receive salvaged surgical treatment. Disease-specific death was noted in 10 patients. The 5-year RFS and DSS rates were 67.3% and 65.7%, respectively. In a multivariate analysis, only the factor of perineural invasion was independently correlated with death.

CONCLUSION

Parotid sarcomatoid carcinoma carries a poor prognosis, and perineural invasion was the most important predictive factor.

LEVEL OF EVIDENCE

2b Laryngoscope, 129:1137-1140, 2019.

Contemporary Management of Benign and Malignant Parotid Tumors

To report the standard of care, interesting new findings and controversies about the treatment of parotid tumors. Relevant and actual studies were searched in PubMed and reviewed for diagnostics, treatment and outcome of both benign and malignant tumors. Prospective trials are lacking due to rarity of the disease and high variety of tumor subtypes. The establishment of reliable non-invasive diagnostics tools for the differentiation between benign and malignant tumors is desirable. Prospective studies clarifying the association between different surgical techniques for benign parotid tumors and morbidity are needed. The role of adjuvant or definitive radiotherapy in securing loco-regional control and improving survival in malignant disease is established. Prospective clinical trials addressing the role of chemotherapy/molecular targeted therapy for parotid cancer are needed. An international consensus on the classification of parotid surgery techniques would facilitate the comparison of different trials. Such efforts should lead into a clinical guideline.

Validation and Comparison of the 7th Edition of the American Joint Committee on Cancer Staging System and Other Prognostic Models to Predict Relapse-Free Survival in Asian Patients with Parotid Cancer

Purpose: Parotid cancer is a rare malignancy characterized by a heterogeneous histologic subtype and distinct biologic behavior. The present study aimed to externally validate and compare the performances of the American Joint Committee on Cancer (AJCC) staging system (7^th Edition), Carrillo score, and Vander Poorten score in the prediction of tumor relapse probability in a large cohort of Asian parotid cancer patients. Methods: In total, 261 patients who underwent primary surgery for localized parotid cancer between 2002 and 2014 at the four affiliated hospitals of Chang Gung Memorial Hospital were identified. All patients were categorized into different prognostic groups defined by these three models for the comparison of associated relapse-free survival (RFS) rates. Results: The 5-year overall survival, cancer-specific survival, and RFS rates were 82.9%, 86.2%, and 77.5%, respectively. All three models were significantly powerful in discriminating between the tumors of patients in the lowest and highest risk groups. The c-statistic for predicting the 5-year RFS was 0.74 for the AJCC staging, 0.74 for the Vander Poorten score, and 0.62 for the Carrillo score. The AJCC staging and Vander Poorten score gave significantly high c-statistic values compared to the Carrillo score. Conclusion: Our data validated that all three models are significantly powerful in discriminating tumor relapse between patients in lowest and highest risk groups. The AJCC system and Vander Poorten score proved superior to the Carrillo score, and showed similar performances in discriminating between the 5-year RFS probabilities of low and high-risk Asian parotid cancer patients.

Comparison of Pencil Beam Scanning Proton- and Photon-Based Techniques for Carcinoma of the Parotid

Purpose

To report the dosimetric advantages of a comparison between pencil beam scanning (PBS) proton therapy versus intensity-modulated radiation therapy (IMRT) for parotid gland cancers.

Patients and Methods

This was a retrospective, dosimetric comparison of 8 patients who received external beam radiation therapy at our institution between 2009 and 2011. Two separate plans were generated for each patient: 1 IMRT and 1 PBS plan. The prescription dose for each plan was 60 Gy for IMRT and 60 Gy (RBE) for PBS. We measured dose-volume relationships for target volumes and organs at risk with each treatment technique. Dosimetric comparisons for each organ at risk were made by using the Wilcoxon signed rank test. All tests were 2-tailed, with P values < .05 considered statistically significant.

Results

The mean patient planning target volume was 160.9 cm3 (SD 74.6). Pencil beam scanning, compared to IMRT, significantly reduced the mean dose to the following structures: ipsilateral temporal lobe (2.86 versus 9.59 Gy (RBE), P = .01), oral cavity (0.58 versus 13.48 Gy (RBE), P = .01), mandible (V50: 7.4% versus 12.8%, P = .01), contralateral parotid gland (0.003 versus 4.64 Gy (RBE), P = .01), ipsilateral submandibular gland (16.59 versus 38.94 Gy (RBE), P = .03), and contralateral submandibular gland (0.02 versus 5.34 Gy (RBE), P = .01). Pencil beam scanning also significantly reduced the maximum dose delivered to the brainstem (7.1 versus 30.9 Gy (RBE), P = .01).

Conclusion

Pencil beam scanning allows for superior normal tissue sparing while still maintaining excellent target coverage in patients with resected parotid gland cancers. These findings suggest that PBS may allow for an improved therapeutic index for these patients. Clinical outcomes with PBS should be evaluated prospectively, with a focus on disease outcomes as well as treatment-related toxicities and patient quality of life.

Predictors of survival in parotid small cell carcinoma: A study of 344 cases

OBJECTIVES/HYPOTHESIS

We sought to better characterize patient, tumor, and long-term survival characteristics of parotid small cell carcinoma (SmCC) with the National Cancer Database (NCDB).

STUDY DESIGN

Retrospective database review.

METHODS

We reviewed the NCDB (1998-2012) for all cases of parotid SmCC. Relevant demographic, tumor, and survival variables were extracted and analyzed. Cox multivariate regression was performed to identify prognosticators.

RESULTS

Out of 30,813 parotid gland cancers in the NCDB, we found 344 cases of parotid SmCC (1.11%). Age at diagnosis ranged from 23 to 91 years (mean = 73 years). Most patients (73.0%) were male. Most tumors were 2 to 4 cm in size (51.4%). Regional metastases were common (50.8% cN+ and 65.1% pN+) and distant metastasis (7.3%) was uncommon. Occult nodes were found in 14.4% of cases. Overall survival at 5 and 10 years was 37% and 20%, respectively. Although numerous variables were found to significantly impact survival on univariate regression analysis, age (hazard ratio [HR]: 1.05, 95% confidence interval [CI]: 1.03-1.08, P < .001), tumor size of 2 to 4 cm (HR: 2.51, 95% CI: 1.83-5.11, P = .011), tumors >4 cm (HR: 3.44, 95% CI: 1.63-7.27) and distant metastasis (HR: 2.06, 95% CI: 1.02-4.14, P = .043) remained significant prognosticators in our multivariate model. Nodal disease was not a significant risk factor after adjustment (P = .055).

CONCLUSIONS

SmCC is a rare parotid malignancy with a poor prognosis. Regional metastases were common, whereas distant metastases were uncommon. Elective neck treatment should be considered due to the incidence of occult nodal disease.

LEVEL OF EVIDENCE

4 Laryngoscope, 126:2036-2040, 2016.

Clinicopathologic factors associated with recurrence in low- and high-grade parotid cancers

BACKGROUND

The purpose of this study was to determine clinicopathological correlates of outcome among patients with parotid gland cancer.

METHODS

The medical records of 126 patients treated by surgery for localized parotid cancer were retrospectively reviewed to identify the clinicopathologic correlates of recurrence-free survival (RFS) according to histologic grade.

RESULTS

Multivariate analysis revealed that age and lymphovascular invasion were significant factors for recurrence in patients with low-grade cancer (p = .049 and p = .019, respectively), whereas perineural invasion was the only significant factor in patients with high-grade cancer (p = .001). The most frequent recurrence site tends to be different according to histologic grade: local recurrence at low-grade cancer (8.3%) and distant at high-grade cancer (13.6%). The duration of RFS was significantly longer in low-grade cancer than high-grade cancer in regional and distant recurrence (p = .044 and p = .016, respectively).

CONCLUSION

Consideration of different factors may be required for individual low-grade and high-grade parotid cancers when predicting the risk of recurrence. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1788-E1793, 2016.

Predictors of Nodal Metastasis in Parotid Malignancies: A National Cancer Data Base Study of 22,653 Patients

OBJECTIVE

(1) To identify predictors of nodal disease in parotid malignancies using various clinical and pathologic variables. (2) To examine the effect of nodal disease on overall survival (OS) in parotid cancers

STUDY DESIGN

Retrospective database review.

SETTING

National Cancer Data Base (1998-2012).

SUBJECTS AND METHODS

We identified all cases of primary parotid malignancies in the United States between 1998 and 2012 in the National Cancer Data Base. Eight histopathologies, constituting >80% of all cases, were examined for nodal metastasis and survival.

RESULTS

We identified 22,653 cases of primary parotid cancer. Eight major histologies were studied, with mucoepidermoid carcinoma (31%), acinic cell carcinoma (18%), adenocarcinoma (14%), and adenoid cystic carcinoma (9%) being most common. Regional nodal disease incidence was 24.4% overall and varied by histopathology. Salivary ductal carcinoma had the highest incidence of both nodal metastasis and occult lymph node metastasis. Overall, N0 patients lived significantly longer than N+ (5-year OS, 79% vs 40%; P < .001). Low-grade disease had significantly better survival than high-grade (5-year OS, 88% vs 69%; P < .001). Occult nodal disease was found in 10.2% and varied by histopathology.

CONCLUSION

Regional lymph node metastasis significantly decreases survival in many parotid malignancies. High-grade cancers had higher incidences of regional disease than did low grade. Adenocarcinoma had the highest mortality when regional disease was present. Incidence of occult disease varied by histology, but incidence was <10% for all low-grade disease. High T stage and grade are significant independent predictors of nodal disease for most histopathologies.

Oncological and functional results after the surgical treatment of parotid cancer

The objective of this study was to analyze the oncological and functional outcomes after the surgical treatment of parotid cancer. We reviewed 80 primary parotid carcinomas retrospectively. A superficial parotidectomy was performed in 10 patients; 27 patients underwent total parotidectomy and 43 patients underwent radical parotidectomy. A facial-facial nerve anastomosis was chosen for the facial nerve reconstruction in eight patients, while an interpositional graft was selected in 24 patients. The overall N-positive rate of pathology was 21.3%. The rate of occult metastasis was 8.1%. High-grade carcinoma and lymphovascular emboli were independent factors for nodal metastasis. The 5-year disease-free survival and overall survival rates were 79.7% and 78.8%, respectively. Preoperative facial nerve palsy and extraparenchymal invasion were the independent factors associated with poor disease-free survival. Of the 41 patients in the facial nerve preservation group, 13 (31.7%) had transient facial nerve paresis. In the facial nerve sacrifice group of 39 cases, (sub)total recovery (House-Brackmann grade I/II) occurred in 14 (35.9%), partial recovery (House-Brackmann grade III/IV) in 13 (33.3%), and no recovery (House-Brackmann grade V) in 12 (30.8%). Facial nerve palsy upon presentation and extraparenchymal invasion indicate a grave prognosis. Facial nerve function after proper reconstruction is tolerable.

Clinical outcome of patients with carcinoma ex pleomorphic adenoma of the parotid gland: a comparative study from a single tertiary center

BACKGROUND

Carcinoma ex pleomorphic adenoma (CXPA) of the parotid gland is a high-grade cancer and the prognosis of this cancer has not been compared with non-CXPA high-grade primary parotid cancer.

METHODS

Retrospective medical chart review of patients with surgically treated high-grade primary parotid cancer (21 CXPA and 52 non-CXPA) was performed with correlation with disease-specific survival, locoregional recurrence, and distant recurrence.

RESULTS

Despite having similar stage of cancer and extent of surgical resection, patients with CXPA had a lower disease-specific survival compared to non-CXPA high-grade primary parotid cancer (p = .02). Salivary duct cancer (SDC) was the commonest histologic variant in both cohorts and around 40% of patients with SDC died of distant recurrence that occurred within 3 years from diagnosis.

CONCLUSION

CXPA of the parotid gland is a more aggressive cancer compared to non-CXPA high-grade primary parotid cancer. SDC was associated with a high chance of delayed distant recurrence, which contributed directly to the mortality of this cancer.

Correlation of β-catenin, but not PIN1 and cyclin D1, overexpression with disease-free and overall survival in patients with cancer of the parotid gland

BACKGROUND

Malignant tumors of the salivary glands comprise about 3% to 5% of all head and neck carcinomas. The purpose of our study was to find possible predictive and/or prognostic markers for parotid cancer.

METHODS

A total of 46 tissue samples of carcinomas of the parotid gland were immunohistochemically stained for ß-catenin, cyclin D1, and PIN1. The factors were analyzed regarding their prognostic value for disease-free and overall survival.

RESULTS

An overexpression of the cytoplasmatic ß-catenin was linked to a statistically significant worse outcome regarding disease-free (p = .0296) and overall survival (p = .0416). The 5-year overall survival was 83.9% in patients without and 0% in patients presenting with overexpression of cytoplasmatic ß-catenin. Additionally, Union Internationale Contre le Cancer (UICC) stage correlated with overall survival (p = .0306) and disease-free survival (DFS; p = .0473).

CONCLUSION

Multivariate analysis showed that overexpression of cytoplasmatic ß-catenin and the UICC stage are 2 independent prognostic markers for survival in patients with parotid cancer.

Outcomes of temporal bone resection for locally advanced parotid cancer

This study was conducted to report outcomes and identify factors predictive of survival and recurrence in patients undergoing lateral temporal bone resection (LTBR) as part of an extended radical parotidectomy for parotid cancer. This is a retrospective cohort study which includes all patients undergoing LTBR for parotid cancer between 1994 and 2010 at two affiliated academic centers. Survival and recurrence rates were analyzed using the Kaplan-Meier method and Cox multivariate regression. A total of 12 patients with median follow-up duration of 30.6 months were included: 6 de novo cases and 6 patients referred after local recurrence. Actuarial locoregional control at 2 years was 73%. Most patients (11; 92%) developed disease recurrence with distant metastases the most common site of first failure (83%). Overall and disease-specific survival rates were 80% at 2 years and 22.5% at 5 years. Recurrence-free survival (RFS) was 67% at 2 years and 8.3% at 5 years. On multivariate analysis, surgical margin status was an independent predictor of RFS (hazard ratio = 3.85, p = 0.045). In advanced parotid cancer, LTBR with a goal of gross total resection offers good locoregional control with an acceptable complication rate. The benefits of this surgery must be balanced with the morbidity and low likelihood of long-term survival, with most patients ultimately experiencing disease recurrence and death.