Intraparotid node metastases in adults with parotid mucoepidermoid cancer: an indicator of prognosis?

Occult Nodal Metastases in Individuals with Clinically Node-Negative Salivary Gland Malignancies

OBJECTIVES

Salivary gland malignancies comprise a heterogeneous group of pathologies, for which treatment of the clinically negative neck may vary depending on numerous factors. Herein we present data on occult nodal metastases (ONM) as well as survival and recurrence from a large series of cN0 salivary gland malignancies.

METHODS

Retrospective chart review was conducted on 532 patients, with 389 patients with major salivary gland cancers and 143 patients with minor salivary gland cancers. Demographic and treatment data were included and rates of ONM, overall survival, local recurrence, regional recurrence, and distant recurrence were analyzed.

RESULTS

We found that the overall rate of ONM for parotid was 27% (63/235), for submandibular/sublingual was 35% (18/52), and for minor was 15% (4/26). Analysis of ONM rate at each nodal level was also performed, finding higher rates of level IV and V ONM than prior studies. Submandibular/sublingual and minor salivary gland malignancies showed a predominance of ONMs at levels I-III. Our survival and recurrence rates were similar to those found in previous studies.

CONCLUSION

Our data also demonstrate a predominance of ONM in levels I-III for submandibular/sublingual and minor salivary gland cancers, suggesting elective dissection in these levels.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1705-1715, 2024.

Intraparotid node metastasis affects the long-term survival of patients with resectable recurrent parotid gland carcinoma

PURPOSE

The recurrence rate of parotid gland cancer is high, but research on the prognosis of recurrent parotid gland cancer (RPC) is relatively limited. We aim to determine the potential prognosis factors of RPC.

STUDY DESIGN

Retrospective cohort analysis.

SETTING

Tertiary cancer center.

METHODS

We conducted a retrospective review from 2012 to 2021 on RPC patients treated at the China National Cancer Center (CNCC). To analyze the impact of various variables on overall survival (OS) after recurrence, a univariate and multivariate Cox proportional hazard model was employed.

RESULTS

A total of 50/218 (23.0%) patients diagnosed with RPC and underwent surgery. The 5-year OS of all RPC patients in this cohort was 61.9%. 5 of 50 patients (10%) exhibited intraparotid node (IPN) metastasis. By univariate and multivariate analyses, we found that IPN metastasis was one of the prognostic factors of OS (p = 0.039) in RPC patients. The presence of IPN metastasis was also related to poor survival in individuals with negative cervical lymph nodes (CN0) (p = 0.011). In terms of the influence of surgical margins on prognosis, our findings revealed that RPC patients with negative margins exhibited a higher survival result than those with positive margins (p = 0.002).

CONCLUSION

According to this study, IPN metastasis indicate a high incidence of mortality in recurrent parotid cancer patients. Particularly, in CN0 patients, the presence of IPN metastasis was associated with poor survival in CN0 patients.

Locoregional metastatic behavior in a complex mosaic of primary malignant tumors of the parotid gland

BACKGROUND

The aim of the study was to investigate primary locoregional metastatic behavior in a large sample of various malignant tumors of the parotid gland with varying grades following surgical treatment consisting of complete parotidectomy and neck dissection.

METHODS

The records of all patients treated for primary malignant tumors of the parotid gland by means of complete parotidectomy and neck dissection between 2007 and 2022 were studied retrospectively.

RESULTS

196 patients formed our study sample (98 females, 98 males). The mean age was 65.7 years (22-101 years). 92 cases presented with low-grade subtypes, 19 with intermediate-grade, and 85 with high-grade carcinomas. The locoregional lymphatic network had been invaded in a total of 66/196 cases (33.6 %). The intraparotid lymph nodes were positive in 54/196 cases (27.5 %) and the cervical lymph nodes in 41/196 cases (20.9 %). In 12 out of the 66 cases with a pN+ status, the neck had been invaded without involvement of the intraparotideal lymph nodes (18.2 %). Male patients tended to suffer from more aggressive carcinomas, and high-grade subtypes presented significantly more frequently as locally advanced tumors. Higher grading was significantly associated with the involvement of the parotid (p < 0.001) and cervical (p < 0.001) lymph nodes. Intermediate and low-grade cases presented similar behavior concerning tumorous invasion of the lymphatic network of the parotid gland (p = 0.522) and the neck (p = 0.467).

CONCLUSION

The locoregional metastatic potential of parotid malignant tumors depends upon a variety of histopathologic factors, which have to be considered in the decision-making process concerning the management of locoregional lymph nodes.

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.

Limited parotid surgery as sole form of treatment for carefully selected malignant tumours of the parotid gland: Still sufficient on the long-term?

BACKGROUND

The aim of the study was to investigate the oncological and functional outcome following extracapsular dissection as the sole form of treatment in locally limited low-grade malignant parotid tumours in the long term.

METHODS

The records of all patients treated for T1-T2 low-grade malignant tumours of the parotid gland solely by means of extracapsular dissection between 2005 and 2017 were studied retrospectively.

RESULTS

A total of 16 cases formed our study sample (7 men, 9 women). Their mean age was 50.2 years (21-84 years). Mean follow-up was 107 months (60-201 months). In 6 cases the tumour was an acinic cell carcinoma, in 9 cases a mucoepidermoid carcinoma and in one case a basal cell adenocarcinoma. Regarding the T category, the tumour was Tis in one case, T1 in 12 cases and T2 in three cases. The five-year disease-specific survival rate was 100 %, as was local disease control. Facial nerve function was House-Brackmann grade I without exception.

CONCLUSIONS

Our study showed very encouraging long-term results following primary extracapsular dissection as the sole surgical therapy for carefully selected low-stage, low-grade, inferiorly located lesions in patients with high compliance.

LAY SUMMARY

The "one-size-fits-all" strategy of complete parotidectomy with neck dissection might be tantamount to overtreatment by less aggressive cases of parotid cancer. Extracapsular dissection seems to be oncologically sufficient for carefully selected T1-T2 low-grade cases in the long-term in patients with ensured follow-up.

Investigation of locoregional metastatic behavior in low-grade malignant tumors of the parotid gland

BACKGROUND

The aim of the study was to investigate primary locoregional metastatic behavior in a large sample of low-grade malignant tumors of the parotid gland following surgical treatment consisting of complete parotidectomy and neck dissection.

METHODS

The records of all patients treated for low-grade malignant tumors of the parotid gland by complete parotidectomy and neck dissection between 2007 and 2022 were studied retrospectively.

RESULTS

94 patients formed our study sample (50 females, 44 males, female to male ratio: 1.14). The mean age was 59 years (range 15-95 years). The mean number of lymph nodes in the specimen from complete parotidectomy was 3.33 (range: 0-12). The mean number of involved lymph nodes in the parotid gland was 0.05 (range: 0-1). The mean number of lymph nodes in the specimen from the ipsilateral neck dissection was 16.2 (range 4-42). The mean number of involved lymph nodes in the neck dissection specimen was 0.09 (range: 0-2). Comparison of T1-T2 vs. T3-T4 cases revealed no statistically significant difference concerning the tumorous involvement of the lymphatic network (x² = 0.719, p = 0.396).

CONCLUSION

Low-grade primary malignant tumors of the parotid gland are characterized by an initially low metastatic potential, which justifies conservative forms of surgical treatment.

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.