Deep Parotid Lymph Node Metastasis Is Associated With Recurrence in High-Grade Mucoepidermoid Carcinoma of the Parotid Gland

Neck management in metastatic cutaneous squamous cell carcinoma of the head and neck

Objective

Optimal neck management remains unclear in head and neck cutaneous squamous cell carcinoma (HNcSCC) with parotid metastasis. Our goal was to compare the impact of different cervical treatments on HNcSCC with parotid metastasis.

Methods

Patients were retrospectively included. The primary outcome variables were regional control (RC) and disease-specific survival (DSS). The impacts of observation, elective neck irradiation (ENI), and elective neck dissection (END) were analyzed using the Cox model and presented as hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

In total, 268 patients were enrolled. In the Cox model for RC, compared with ENI, observation was associated with a significantly higher risk of regional recurrence (p = 0.001, HR = 2.50, 95%CI = 1.45-4.30). However, END showed a comparable influence on regional recurrence (p = 0.246, HR = 0.70, 95%CI = 0.38-1.28). In the Cox model for DSS, END demonstrated a similar HR of 0.62 (95%CI = 0.30-1.26) compared to ENI (p = 0.184). However, patients who underwent observation were associated with an additional nearly twofold risk of cancer-related mortality (HR = 2.85, 95%CI = 1.55-5.23). Subgroup analysis showed that ENI predicted comparable RC (p = 0.389) and DSS (p = 0.346) in patients with one or two metastatic parotid lymph nodes, but worse RC (p = 0.007) and DSS (p = 0.024) in patients with more than three positive lymph nodes.

Conclusion

In HNcSCC with parotid metastasis, elective treatment of neck lymph nodes with END or ENI should always be performed.

Clinicopathological Predictors of Survival for Parotid Mucoepidermoid Carcinoma: A Systematic Review

OBJECTIVE

Various prognostic factors are associated with the survival of patients with parotid mucoepidermoid carcinoma (MEC). The aim of this systematic review is to summarize the clinical and pathologic prognostic factors on survival outcomes in patients with parotid MEC.

DATA SOURCES

Articles published from database inception to July 2020 on OVID Medline, OVID Embase, Cochrane Central, and Scopus.

REVIEW METHODS

Studies were included that reported clinical or pathologic prognostic factors on survival outcomes for adult patients with parotid MEC. Data extraction, risk of bias, and quality assessment were conducted by 2 independent reviewers.

RESULTS

A total of 4290 titles were reviewed, 396 retrieved for full-text screening, and 18 included in the review. The average risk of bias was high, and quality assessment for the prognostic factors ranged from very low to moderate. Prognostic factors that were consistently associated with negative survival outcomes on multivariate analysis included histologic grade (hazard ratio [HR], 5.66), nodal status (HR, 2.86), distant metastasis (HR, 3.10-5.80), intraparotid metastasis (HR, 13.52), and age (HR, 1.02-6.86). Prognostic factors that inconsistently reported associations with survival outcomes were TNM stage, T classification, and N classification.

CONCLUSION

Histologic grade, nodal status, distant metastasis, intraparotid metastasis, and age were associated with worse survival outcomes. These prognostic factors should be considered when determining the most appropriate treatment and follow-up plan for patients with parotid MEC.

Role of Intra-Parotid Lymph Node Metastasis in Primary Parotid Carcinoma

The parotid gland contains intra-glandular lymph nodes, the distribution of which is crucial for understanding the pathogenesis of intra-parotid lymph node metastases of parotid carcinoma and other head and neck carcinomas. Positive intra-parotid lymph node metastasis predicts the risk of positive cervical nodal metastasis. It is important to establish whether prophylactic neck dissection, including intra-parotid lymph nodes, contributes to treatment outcomes. The presence or absence of intra-parotid lymph nodes or metastasis-positive lymph nodes warrants further study. A preoperative diagnosis by imaging and fine-needle aspiration cytology of intra-parotid lymph nodes is difficult. Although intraoperative frozen section biopsy is performed during surgery, it is challenging to identify intra-parotid lymph nodes. The number of lymph nodes was the largest (47%) in the lower half of the superficial lobe, with 35% of nodes being concentrated in the inferior part of the cervicofacial branch, i.e., the lower pole of the parotid gland. Therefore, superficial parotidectomy and lower pole lobectomy need to be performed in cases in which a malignant tumor localizes to the superficial lobe or a lower pole. When intra-parotid lymph node metastases are detected during surgery, selective neck dissection (at least levels II and III) needs to be simultaneously performed.

Occult neck metastases risk factors and the role of elective neck dissection in cT3-4N0 adenoid cystic carcinoma of the parotid gland

Objectives

To determine the predictor for occult neck metastases and the role of elective neck dissection (END) in cT3-4N0 parotid adenoid cystic carcinoma (ACC).

Methods

Patients with surgically treated parotid ACC were retrospectively enrolled. Predictors of occult neck metastases and the effect of END on disease specific survival (DSS), overall survival (OS), locoregional control survival (LRC), and distant metastasis free survival (DMS) were analyzed.

Results

Occult neck metastases occurred in 35 (19.7%) of the 178 patients undergoing an END. The tumor stage [p=0.011, 4.215 (1.387–10.435)] and intra-parotid lymph node metastasis [p=0.032, 3.671 (1.693–8.775)] were related to the possibility of occult neck metastases independently. The END group had better 10-year LRC than the observation group (56% vs. 43%, p=0.002) and also better 10-year DMS than the observation group (43% vs. 32%, p<0.001). The two groups had similar 10-year DSS (40% vs. 33%, p=0.230) and OS (31% vs. 23%, p=0.094) rates. Furthermore, the Cox model confirmed that END was independently associated with better LRC rate [p=0.022, 2.576 (1.338–6.476)] and better DMS [p=0.011, 2.343 (1.274–7.462)].

Conclusions

Occult neck metastases in cT3-4N0 parotid ACC was not common. A T4 tumor with intra-parotid lymph node metastasis had the highest possibility of occult neck metastases. END had no effect on DSS or OS but significantly decreased the risk of locoregional recurrence and distant metastasis.

Prognostic role of intraparotid lymph node metastasis in primary parotid cancer: Systematic review

BACKGROUND

The prognostic importance of intraparotid lymph node metastasis (P+) in patients with primary parotid gland carcinoma is unclear.

METHODS

Nineteen retrospective and noncomparative cohort studies, published between 1992 and 2020, met the inclusion criteria and included 2202 patients for this systematic review.

RESULTS

The pooled prevalence of the P in adult patients in the unselected studies was 24.10% (95% confidence interval = 17.95-30.25). The number of P+ lymph nodes per patient was counted in only three studies and ranged from 1 to 11. The 5-year recurrence-free survival rate based on Kaplan-Meier analysis varied from 83% to 88% in P- patients compared to 36% to 54% in P+ patients. The average hazard ratio for tumor recurrence in patients with P+ compared to P- was 2.67 ± 0.58.

CONCLUSIONS

P+ is an independent negative prognostic factor in primary parotid gland cancer and should be included into the treatment planning.

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.