What is the role of elective neck dissection in low-, intermediate-, and high-grade mucoepidermoid carcinoma?

Epidemiology, prognostic factors, and treatment of head and neck mucoepidermoid carcinoma: Analysis of the surveillance, epidemiology, and end results database

OBJECTIVES

To investigate prognostic factors in patients with head and neck Mucoepidermoid Carcinoma (MEC), especially the impact of treatment modalities on survival.

METHODS

Patients with primary head and neck MEC between 2000 and 2015 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Prognostic factors related to Overall Survival (OS) and Cancer-Specific Survival (CSS), as well as the impact of treatments, were evaluated by multivariable Cox regression analysis.

RESULTS

We identified 2692 patients diagnosed with head and neck MEC, of whom 1397 (51.89%) had a parotid gland primary, 569 (22.14%) died, and 341 (12.67%) died of MEC. Older age (≥53 years), males, unmarried, lower income, tumor site in other head and neck areas, higher tumor grade, larger tumor size, and higher stage were related to poorer OS and CSS. Patients who did not undergo surgery (HR=3.20, 95% CI 2.45‒4.18) had worse OS, while no significant difference was detected between partial and total organ excision on patients' OS (p=0.729). For combination therapy, patients who received radiotherapy only (HR=3.21, 95% CI 2.27-4.53) or no surgery and no radiotherapy (HR=2.59, 95% CI 1.83-3.67) were correlated with worse OS (vs. surgery only), but no significant difference was detected between surgery only and surgery combined with radiotherapy on patients' OS (p=0.218). For CSS, the corresponding results were consistent with OS.

CONCLUSION

Surgical resection only may be a better survival option for head and neck MEC.

Elective nodal dissection for cN0 intermediate-grade parotid mucoepidermoid carcinoma: A NCDB study

PURPOSE

To determine the occult nodal disease rate and whether elective regional lymph node dissection (RLND) confers any 10-year overall survival (OS) in cN0 intermediate-grade mucoepidermoid carcinoma (MEC) of the parotid gland.

MATERIALS & METHODS

The National Cancer Database was reviewed from 2004 to 2016 on adults with cT1-4aN0M0 intermediate-grade parotid MEC undergoing resection with/without RLND. Comparisons between patients with and without RLND were made. Occult nodal rate and 10-year overall survival (OS) were determined.

RESULTS

Out of 898 included patients with cN0 intermediate grade parotid MEC undergoing elective RLND, the occult nodal rate was 7.6%. This was significantly different from low-grade (3.9%) and high-grade (25.7%) cN0 disease. When stratified by pT-classification, marginal differences were identified between low-grade and intermediate-grade tumors, whereas high-grade tumors demonstrated increased occult nodal disease with low T-stage (pT1-pT2, 20.4% vs. 5.1%) and high T-stage (pT3-pT4a, 32.1% vs. 17.6%). Patients undergoing elective RLND were more often treated at an academic facility (53.8% vs. 41.2%), had higher pT3-pT4 tumors (19.2% vs. 10.4%), and more frequently underwent total/radical parotidectomy (46.0% vs. 29.9%) with adjuvant radiation therapy (53.8% vs. 41.0%) Cox-proportional hazard modeling did not identify RLND, regardless if stratified by nodal yield or pT-classification, nor nodal positivity as significant predictors of 10-year OS.

CONCLUSIONS

The occult nodal disease in intermediate-grade parotid MEC is low and similar to low-grade. Elective RLND may have a limited impact on OS, though its effect on locoregional control remains unknown.

LEVEL OF EVIDENCE

III.

Number of positive lymph nodes affects oncologic outcomes in cN0 mucoepidermoid carcinoma of the major salivary gland

The survival significance of the number of positive lymph nodes in salivary gland carcinoma remains unclear. Thus, the current study aimed to determine the effect of the number of positive lymph nodes on disease-specific survival (DSS) and overall survival (OS) in cN0 mucoepidermoid carcinoma (MEC) of the major salivary gland. Patients surgically treated for MEC of the major salivary gland between 1975 and 2019 were retrospectively enrolled from the surveillance, epidemiology, and end results database. The total population was randomly divided into training and test groups (1:1). Primary outcome variables were DSS and OS. Prognostic models were constructed based on the independent prognostic factors determined using univariate and multivariate Cox analyses in the training group and were validated in the test group using C-index. A total of 3317 patients (1624 men and 1693 women) with a mean age of 55 ± 20 years were included. The number of positive lymph nodes was an independent prognostic factor for both DSS and OS, but the effect began when at least two positive lymph nodes for DSS and three positive lymph nodes for OS were found. Predictive models for DSS and OS in the training group had C-indexes of 0.873 (95% confidence interval [CI] 0.853-0.893) and 0.835 (95% CI 0.817-0.853), respectively. The validation of the test group showed C-indexes of 0.877 (95% CI 0.851-0.902) for DSS and 0.820 (95% CI 0.798-0.842) for OS. The number of positive lymph nodes was statistically associated with survival in cN0 major salivary gland MEC. The current prognostic model could provide individualized follow-up strategies for patients with high reliability.

Influence of Grading on Management and Outcome in Mucoepidermoid Carcinoma of the Parotid-A Multi-institutional Analysis

OBJECTIVE

To evaluate clinical outcome of low (G1), intermediate (G2), and high-(G3) grade mucoepidermoid carcinomas (MEC) of the parotid gland.

STUDY DESIGN

Retrospective chart review including 212 patients. Clinicopathological data was statistically analyzed regarding grading, overall survival (OS), disease-free survival (DFS) and disease-specific survival (DSS).

RESULTS

105 (49.5%) G1, 73 (34.5%) G2, and 34 (16%) G3 MEC were included and 56 (26.4%) patients presented with neck node metastases. The risk of occult nodal metastases was significantly associated with grading and increased from 9.2% in G1 to 26.7% and 27.8% in G2 and G3 tumors, respectively (p = 0.008). Elective periparotid and cervical lymph node dissection was performed in 170 (80.2%) and 70 (33%) patients, respectively. All patients with positive periparotid nodes when subjected to an additional neck dissection had associated cervical neck node involvement (p < 0.001). Grading was an independent significant prognostic factor for OS (HR 4.05; 95%CI: 1.15-14.35; p = 0.030) and DSS (HR 17.35; 95%CI: 1.10-273.53; p = 0.043). In a subgroup analysis, elective neck dissection (END) was also significantly associated with a better DFS (p = 0.041) in neck node-negative G1 MECs.

CONCLUSION

The risk of occult nodal metastasis in intermediate-grade MEC is as high as in high-grade MEC and that END in G1 tumors is associated with a prolonged DFS. Additionally, periparotid node involvement seems to be a predictor for positive neck node involvement. This study presents some preliminary data to consider END in clinically neck node negative patients with parotid MEC; however, larger series are needed.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:124-132, 2023.

Presentation and outcomes of patients with clinically T1-2, N0 parotid mucoepidermoid carcinoma: The roles of elective neck dissection and adjuvant radiotherapy

Objectives

Examine the role of elective neck dissection (END) and adjuvant radiotherapy (RT) in early‐stage clinically N0 parotid mucoepidermoid carcinoma (MEC).

Methods

The study is a retrospective analysis of the National Cancer Database, 2004–2016. The study population included adult patients with MEC who underwent parotidectomy.

Results

A total of 1233 patients were included. Histopathology demonstrated well, moderately, and poorly differentiated MEC 47.12%, 39.98%, and 12.90% of the time, respectively. END was performed in 78.67% of patients, resulting in nodal upstaging in 4.43% and identification of extracapsular extension (ECE) in 0.72%. RT was utilized in 67.33% of patients with advanced pathological features. Neither END nor RT improved overall survival separately (p < 0.05) or combined (adjusted HR: 1.19, 95%CI: 0.52, 2.70, p = 0.68).

Conclusion

This study provides an epidemiological perspective regarding patients with clinically T1‐2, N0 MEC. There was no observed survival advantage with END and RT.

Indications and outcomes for elective dissection of level V in primary parotid cancer

BACKGROUND

The extent of cervical lymphadenectomy required for primary parotid cancer is not well-established.

METHODS

In this retrospective case-control study, 84 patients who underwent primary parotidectomy and neck dissection for primary parotid cancer between 2010 and 2019 were identified and analyzed.

RESULTS

Of the 84 patients, 37 underwent elective level V neck dissection. All six (16.0%) who had occult level V nodes had clinically evident, preoperative anterior cervical metastases, a statistically significant finding. No other clinical factors are correlated with posterior neck involvement. There was no significant difference in disease-free or overall survival for patients with occult level V disease relative to positive lymph nodes in other levels.

CONCLUSIONS

Patients with clinically evident anterolateral cervical lymphatic metastases from parotid cancer preoperatively have high rates of occult level V nodes. Level V neck dissection can be avoided in cN0 patients and offered no survival advantage.

Management of Malignant Salivary Gland Conditions

Salivary cancers are rare tumors that arise in major and minor salivary glands. Workup almost always includes fine-needle aspiration or core needle biopsy in select cases. Imaging with ultrasound, computed tomography, or MRI is also helpful, particularly with MRI to assess facial nerve involvement or skull base involvement. Preserving function of the facial nerve is of paramount importance, and the standard of care is to not sacrifice facial nerve except in instances of gross encasement and inability to dissect tumor off of the nerve. Adjuvant radiation and chemotherapy offer survival advantages for select patients.

miR-22 and miR-205 Drive Tumor Aggressiveness of Mucoepidermoid Carcinomas of Salivary Glands

Objectives

To integrate mRNA and miRNA expression profiles of mucoepidermoid carcinomas (MECs) and normal salivary gland (NSGs) tissue samples and identify potential drivers.

Material and Methods

Gene and miRNA expression arrays were performed in 35 MECs and six NSGs.

Results

We found 46 differentially expressed (DE) miRNAs and 3,162 DE mRNAs. Supervised hierarchical clustering analysis of the DE transcripts revealed two clusters in both miRNA and mRNA profiles, which distinguished MEC from NSG samples. The integrative miRNA-mRNA analysis revealed a network comprising 696 negatively correlated interactions (44 miRNAs and 444 mRNAs) involving cell signaling, cell cycle, and cancer-related pathways. Increased expression levels of miR-205-5p and miR-224-5p and decreased expression levels of miR-139-3p, miR-145-3p, miR-148a-3p, miR-186-5p, miR-338-3p, miR-363-3p, and miR-4324 were significantly related to worse overall survival in MEC patients. Two overexpressed miRNAs in MEC (miR-22 and miR-205) were selected for inhibition by the CRISPR-Cas9 method. Cell viability, migration, and invasion assays were performed using an intermediate grade MEC cell line. Knockout of miR-205 reduced cell viability and enhanced ZEB2 expression, while miR-22 knockout reduced cell migration and invasion and enhanced ESR1 expression. Our results indicate a distinct transcriptomic profile of MEC compared to NSG, and the integrative analysis highlighted miRNA-mRNA interactions involving cancer-related pathways, including PTEN and PI3K/AKT.

Conclusion

The in vitro functional studies revealed that miR-22 and miR-205 deficiencies reduced the viability, migration, and invasion of the MEC cells suggesting they are potential oncogenic drivers in MEC.

The role of total parotidectomy in high-grade parotid malignancy: A multisurgeon retrospective review

PURPOSE

Determine rates of intra-parotid and neck nodal metastasis, identify risk factors for recurrence, and report outcomes in patients with primary high-grade parotid malignancy who undergo total parotidectomy and neck dissection.

MATERIALS & METHODS

Retrospective review of patients undergoing total parotidectomy and neck dissection for high-grade parotid malignancy between 2005 and 2015. The presence and number of parotid lymph nodes, superficial and deep, as well as cervical lymph nodes involved with metastatic disease were assessed. Risk factors associated with metastatic spread to the parotid deep lobe were identified and recurrence rates reported.

RESULTS

75 patients with median follow-up time of 47 months. 35 patients (46.7%) had parotid lymph node metastasis. Seven patients (9.3%) had deep lobe nodal metastasis without metastasis to the superficial lobe nodes. Nine patients (12%) had positive intra-parotid nodes without positive cervical nodes. Cervical nodal disease was identified in 49.3% patients (37/75). Local, parotid-bed recurrence rate was 5.3% (4/75). Regional lymph node recurrence rate was also 5.3% (4/75). Rate of distant metastasis was 30.6% (23/75). The overall disease free survival rate for all patients at 2 and 5 years were 71% and 60% respectively.

CONCLUSION

Parotid lymph node metastasis occurred at a similar rate to cervical lymph node metastasis (46.7% and 49.3%, respectively). Deep lobe parotid nodal metastasis occurred in nearly a quarter of patients and can occur without superficial parotid nodal metastasis. Rate of recurrence in the parotid bed, which may represent local or regional recurrence, was similar to regional cervical lymph node recurrence. Total parotidectomy and neck dissection should be considered high-grade parotid malignancy regardless of clinical nodal status.

Mucoepidermoid carcinoma of the head and neck: CRTC1/3 MAML 2 translocation and its prognosticators

PURPOSE

Mucoepidermoid carcinoma (MEC) of the head and neck is a prevalent malignant salivary gland tumour with a reported good outcome. The aim of this study was to report the outcome in our centre.

METHODS

A retrospective chart analysis with survival analyses was performed combined with fluorescence in situ hybridization (FISH) analysis to assess CRTC1/3 MAML 2 fusion gene presence.

RESULTS

Sixty-four cases of MEC were identified. Median age at presentation was 51.4 years with a predominance for parotid gland involvement. Five, 10- and 20- year disease-free survival was 98%, 90% and 68%, respectively. Overall survival was 94%, 90% and 64%, respectively. Local recurrence was seen up to 14 years after primary diagnosis; distant metastases were diagnosed up to 17 years later. The overall recurrence rate was less than 20 per cent. CRTC1/3 MAML 2 fusion gene presence showed no survival benefit.

CONCLUSION

MEC of the head and neck has a favorable outcome with the exception of high-grade MEC. PNI and nodal involvement are not rare. CRTC1/3 MAML 2 fusion gene presence showed no survival benefit. The tendency for late onset of loco-regional and distant recurrence should not be underestimated.

Prognostic analysis and nomogram establishment in patients with mucoepidermoid carcinoma of the tongue: a population-based study using the SEER database

OBJECTIVES

To describe the clinicopathological characteristics and determinants of survival of patients with mucoepidermoid carcinoma (MEC) of the tongue.

METHOD

Retrospective population-based study was conducted using the data of patients diagnosed with MEC of the tongue from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2016.

RESULTS

A total of 200 cases of MEC of the tongue were identified. The cohort was composed of 56.5% females. The mean age at diagnosis was 58.8 years. The base of the tongue was the most common primary site (72.5%). Most cases (80.9%) presented with T1 and T2. Lymph node metastases was present in 40.9% of cases, while distant metastases only observed in 2.2% of cases. Overall survival (OS) at 2, 5, and 10 years was 80.2%, 69.8%, and 52.4%, respectively. 77.5 percent of cases (155/200) underwent surgery, and 66 cases received both surgery and radiation therapy. Patients with post-operative radiation had much longer disease-specific survival (DSS). Advanced T stage, distant metastasis contributed independently to shorter OS, while the use of surgery is an independently favorable prognostic factor for OS. In addition, an OS-specific nomogram was established, and the C-index for OS prediction was 0.74 (95% CI 0.67-0.81).

CONCLUSION

This rare malignancy is associated with a generally favorable prognosis, and T stage, distant metastasis as well as surgical therapy are independent predictors of OS.

Intermediate-grade carcinoma of the parotid and the impact of adjuvant radiation

PURPOSE

To determine the influence of adjuvant radiotherapy on survival in surgically-managed early stage intermediate-grade mucoepidermoid and acinic cell carcinoma of the parotid.

MATERIALS AND METHODS

The National Cancer Database was reviewed between 2004 and 2015 to identify patients with intermediate-grade, early T-stage, node-negative parotid carcinoma who underwent parotidectomy ± radiotherapy.

RESULTS

There were 744 patients identified of which 81% had mucoepidermoid carcinoma and 19% had acinic cell carcinoma. Positive surgical margins were identified in 21% and adjuvant radiotherapy was administered in 38% of cases. Of the 159 patients with positive margins, 113 (71%) received adjuvant radiotherapy. Of the 585 patients with negative margins, 173 (30%) underwent adjuvant radiotherapy. In multivariable analysis, age (over 52 years: HR 5.19, 95%CI 2.33-11.57), insurance status (private insurance: HR 0.24 95%CI 0.13-0.43), and extent of parotidectomy (total parotidectomy: HR 2.02 95%CI 1.23-3.31) were significantly associated with overall survival, while adjuvant radiotherapy was not a significant predictive factor (HR 0.81, 95%CI 0.49-1.36). In patients with positive margin resections, however, adjuvant radiation was an independent predictor of improved survival when adjusted for age, insurance status, and extent of parotidectomy (HR 0.34, 95%CI 0.13-0.88). Conversely, in patients with negative margin resections, adjuvant radiation did not influence survival outcomes when adjusted for these covariates (HR 1.02, 95%CI 0.53-1.93).

CONCLUSIONS AND RELEVANCE

In patients with early stage intermediate-grade parotid carcinoma, adjuvant radiotherapy significantly and independently improves survival in those with post-operative positive margins. Adjuvant therapy, however, does not appear to improve survival outcomes in those with negative margin resections.

Oncologic outcome and potential prognostic factors in primary squamous cell carcinoma of the parotid gland

BACKGROUND

Primary parotid squamous cell carcinoma (SCC) is an uncommon tumour, and there is limited data on its prognosis and treatment. The goal of the current study was to analyse the potential prognostic factors and clinical outcomes for this tumour type.

METHODS

Consecutive patients with surgically treated primary parotid SCC were retrospectively enrolled in this study. The primary end point was locoregional control (LRC) and disease-specific survival (DSS), which were calculated by the Kaplan-Meier method. Independent prognostic factors were evaluated by the Cox proportional hazards method.

RESULTS

In total, 53 patients were included for analysis. Perineural and lymphovascular invasion were observed in 21 and 16 patients, respectively. Intraparotid node (IPN) metastasis was reported in 23 patients with an incidence rate of 43.3%. Twenty-six patients with cN0 disease underwent neck dissection, and pathologic node metastasis was observed in 10 cases. The 5-year LRC and DS S rates were 35 and 49%, respectively. The Cox model was used to report the independence of disease stage and IPN metastasis in predicting LRC and the independence of disease stage and perineural invasion in predicting DSS.

CONCLUSIONS

The prognosis of primary parotid SCC is relatively unfavourable. IPN metastasis significantly decreases disease control, disease stage is the most important prognostic factor, and neck dissection is suggested for patients at any stage.

Primary intraosseous mucoepidermoid carcinoma of the mandible: radiographic evolution and clinicopathological features

Mucoepidermoid carcinoma (MEC) can be rarely found as a primarily intraosseous lesion and mistaken for other intraosseous or odontogenic pathology. A 65-year-old man had a poorly defined radiolucency distal to the left mandibular second molar root. Periapical radiographs demonstrated a minor radiolucency from 2.5 years prior. An oral and maxillofacial surgeon felt the radiolucency represented periodontal disease, extracting tooth #18. The differential diagnosis of mixed radiolucent/radio-opaque mandibular lesions includes: (1) fibro-osseous lesion, (2) odontogenic and non-odontogenic cyst, (3) infection and inflammatory lesion, or (4) benign or malignant neoplasm (odontogenic, non-odontogenic, or metastatic). Histological analysis revealed low-grade MEC. A composite resection was performed with a 1 cm margin from first molar to ascending ramus. A buccal fat pad advancement flap covered the defect with an iliac crest bone graft placed later for a resulting osseous defect. Careful examination and diagnostic work-up for odontogenic cysts should be provided as they may harbour malignant tumours.