An evidence-based analysis of the management of N0 neck in patients with cancer of the parotid gland

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.

Utility of Elective Neck Dissection in Clinically Node-Negative Parotid Malignancy

OBJECTIVE

We sought to investigate the utility of elective neck dissection (END) in clinically node-negative parotid malignancy through the evaluation of factors that are associated with receiving END and survival analysis of patients who received END.

STUDY DESIGN

Retrospective cohort database study.

SETTING

The National Cancer Database (NCDB).

METHODS

The NCDB was used to extract patients with clinically node-negative parotid malignancy. END was defined as having 5 or more lymph nodes examined pathologically, as previously defined in the literature. Univariate and multivariate analyses were used to compare predictors of receiving END, rates of occult metastasis, and survival.

RESULTS

Of the 9405 included patients, 3396 (36.1%) underwent an END. END was most frequently performed for squamous cell carcinoma (SCC) and salivary duct histology. All other histologies were significantly less likely to undergo END compared to SCC (p < .05). Salivary ductal carcinoma and adenocarcinoma had the greatest rates of occult node disease (39.8% and 30.0%, respectively), followed by SCC (29.8%). Kaplan-Meier survival analysis showed a statistically significant increase in 5-year overall survival in patients who received END with poorly differentiated mucoepidermoid (56.2% vs 48.5%, p = .004) along with moderately and poorly differentiated SCC (43.2% vs 34.9%, p = .002; 48.9% vs 36.2%, p < .001, respectively).

CONCLUSION

Histological classification is a benchmark for determining which patients should receive an END. We demonstrated an increase in overall survival in patients who undergo END with poorly differentiated tumors of mucoepidermoid and SCC histology. As such, histology should be considered along with clinical T-stage and rate of occult nodal metastasis to determine eligibility for END.

Survival outcomes, prognostic factors, and effect of adjuvant radiotherapy and prophylactic neck dissection in salivary acinic cell carcinoma: A prospective multicenter REFCOR study of 187 patients

BACKGROUND

Acinic cell carcinomas (AciCCs) are malignant tumours of the salivary glands. The aim of this work was to analyse data from the national REFCOR multicenter cohort (i) to investigate the prognostic factors influencing survival outcomes in AciCC, (ii) to assess the impact on survival of postoperative radiotherapy (RT) in patients treated for AciCC without high-grade transformation and (iii) to explore the prognostic impact of prophylactic neck dissection (ND) in patients treated for AciCC of the major salivary glands.

PATIENTS AND METHODS

Data from all the patients treated for salivary AciCC between 2009 and 2020 were extracted from the REFCOR database. Survival outcomes and prognostic factors influencing Disease-Free Survival (DFS) and Overall Survival (OS) were investigated using univariate and multivariate analyses. Propensity score matching was used to assess the impact of postoperative RT and prophylactic ND on DFS.

RESULTS

A total of 187 patients were included. After a median follow-up of 53 months, their 5-year OS and DFS rates were 92.8% and 76.2%, respectively. In multivariate analysis, male sex, older age, higher T and N status, and high grade were independently associated with a worse DFS. In the subpopulation analysed after propensity score matching, patients with cN0 AciCC without high-grade transformation who were treated by surgery and RT did not have an improved DFS compared to patients who were treated by surgery alone (hazard ratio (HR) = 0.87, p = 0.8). Factors associated with nodal invasion were T3-T4 status and intermediate/high histological grade. After propensity score matching, prophylactic ND was associated with a trend toward a better DFS (HR = 0.46, p = 0.16).

CONCLUSIONS

These results suggest that (i) long-term follow-up (>5 years) should be considered in patients with AciCC, (ii) treatment by surgery alone could be an option in selected cN0 patients with AciCC without high-grade transformation and (iii) prophylactic ND may be considered preferentially in patients with T3-T4 status and/or intermediate/high histological grade.

[Application of free peroneal artery chimeric perforator flap in repairing the defect after advanced local lesions resection in parotid gland carcinoma]

OBJECTIVE

To investigate the effectiveness of free peroneal artery chimeric perforator flap in repairing the defect after advanced local lesions resection in parotid gland carcinoma (PGC).

METHODS

Between June 2010 and June 2020, 32 patients with advanced local lesions of PGC were treated with extended radical resection. After that, 17 patients were repaired with the free peroneal artery chimeric perforator flaps (trial group) and another 15 patients were repaired with the pedicled pectoralis major myocutaneous flaps (control group). There was no significant difference in gender, age, disease type, histopathological classification, clinical stage, and pathological stage between groups ( P>0.05). The size of skin flap in trial group ranged from 7 cm×6 cm to 12 cm×8 cm and the size of soleus muscle flap ranged from 5 cm×3 cm to 6 cm×4 cm. The donor sites were repaired with skin grafting. The size of the pedicled pectoralis major myocutaneous flaps in control group ranged from 9 cm×6 cm to 14 cm×7 cm. The donor sites were sutured directly. The operation time, survival rate of flap, and postoperative survival of patients were recorded and compared between groups. At 1 year after operation, the University of Washington quality of life (UW-QOL) questionnaire was used to evaluate the quality of life of patients in the two groups, including appearance, shoulder movement, sociability, masticatory function, speech function, and mood.

RESULTS

The operations completed successfully. The operation time was (6.19±0.72) hours in trial group and (6.41±0.71) hours in control group, showing no significant difference between groups ( t=-0.863, P=0.395). The survival rate of flap in trial group was 94.1% (16/17); and 1 patient suffered from vascular crisis after operation and was replaced with the pedicled pectoralis major myocutaneous flap. The survival rate of flap in control group was 100%. All grafts survived and the incisions healed by first intention in the two groups. All patients were followed up. The follow-up time was 6-60 months (median, 60 months) in trial group and 7-60 months (median, 60 months) in control group. Cumulative survival rates of patients at 1, 3, and 5 years after operation were 94.1%, 64.7%, and 58.8% in trial group, respectively; 86.7%, 66.7%, and 53.3% in control group, respectively. There was no significant difference in the cumulative survival rate between groups ( χ 2=0.090, P=0.762). According to the UW-QOL questionnaire at 1 year after operation, the scores of appearance, shoulder movement, sociability, and mood in trial group were significantly higher than those in control group ( P<0.05); and there was no significant difference in masticatory function and speech function scores between groups ( P>0.05).

CONCLUSION

The peroneal artery perforator has an invariable anatomical relationship. Each perforator emits the muscular branch that nourishes the soleus muscle. Therefore, personalized free peroneal artery chimeric perforator flap can be designed according to the tissue defect, and used to repair the defect after advanced local lesions resection in PGC.

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.

Prognostic indicators in clinically node-negative malignant primary salivary tumours of the parotid: A multicentre experience

OBJECTIVES

Nodal metastasis is an important prognosticator in primary parotid cancers. The management of the clinically node-negative neck is an area lacking consensus. This study investigates the occult nodal metastasis rate, and prognostic indicators in primary parotid cancers.

MATERIALS AND METHODS

We performed a multicentre retrospective case note review of patients diagnosed and treated surgically with curative intent between 1997 and 2020. Demographic, clinic-pathological and follow-up data was recorded.

RESULTS

After exclusions, 334 patients were included for analysis, with a median follow-up of 48 months. The overall rate of occult lymph node metastasis amongst patients undergoing elective neck dissection was 22.4%, with older age, high-grade and more advanced primary tumours being associated with higher rates. On multivariable analysis, age ≥ 60 years (HR = 2.69, p = 0.004), high-grade tumours (HR = 2.70, p = 0.005) and advanced primary tumours (pT3-4, HR = 2.06, p = 0.038) were associated with worse overall survival. Occult nodal metastasis on final pathology was associated with a close-to-significant reduction in regional recurrence free survival (HR = 3.18, p = 0.076).

CONCLUSION

This large series confirms the significant occult lymph node metastasis rate in primary parotid cancer, and demonstrates the importance of primary histology, tumour grade and stage in predicting survival outcome. This data supports the use of elective neck dissection in patients with high-risk tumours.

Elective neck dissection in primary parotid carcinomas: A systematic review and meta-analysis

BACKGROUND

To estimate the rate of occult cervical lymph node metastases in cN0 patients affected by primary parotid carcinomas and to scrutinize the evidence on the indication and extent of elective neck dissection in these neoplasms.

METHODS

Medline, Embase, Web of Science, Cochrane Library and Scopus were searched until August 31, 2020, to identify studies reporting the use of elective neck dissection in the management of malignant parotid tumours. The PRISMA checklist was used. A single arm meta-analysis was then made to determine the pooled rate of occult lymph node metastases. Risk of bias of the included studies was assessed through the ROBINS-E tool.

RESULTS

The initial search returned 20 541 articles, of which twelve met the inclusion criteria and were included in the meta-analysis. They comprised 1310 patients with parotid carcinoma, of whom 542 cN0 underwent elective neck dissection, which led to the diagnosis of lymph node metastasis (pN+/cN0) in 113 cases. Meta-analysis of the results of elective neck dissection showed an overall rate of occult metastases of 0.22 (99% CI: 0.14-0.30). Locally advanced or high-grade tumours were the commonest indications for elective neck dissection in the included studies. The most dissected lymph node levels were I-II-III, and level II was the commonest site of occult nodal metastases.

CONCLUSIONS

An occult metastasis rate of 0.22 (99% CI: 0.14-0.30) represents a not negligible percentage value, which should encourage further research to outline the most appropriate elective neck management in cN0 patients with parotid carcinomas.

Rate of Occult Neck Nodal Metastasis in Parotid Cancer: A Meta-Analysis

BACKGROUND

The risk for occult neck nodal metastasis in carcinoma of the parotid gland is inconclusive. Therefore, addressing a negative neck prophylactically and the extent to do so remain controversial. This systematic review aimed to determine the rate of occult nodal metastasis for each neck level, and consequently, to elucidate the proper extent of elective neck dissection (END).

METHODS

A meta-analysis of all studies that included patients with a diagnosis of parotid malignancies who underwent an END was performed. The risk for occult nodal metastasis was calculated for each neck level separately.

RESULTS

The search strategy identified 124 papers from January 1980 to December 2019 in the various databases. Nine retrospective studies (n =548) met the inclusion criteria. The risk for occult neck nodal metastasis ranged from 0.0 to 9.43% with a random-effect model of 2.2% for level 1 (n =459), from 3.4 to 28.38% with a random-effect model of 16.51% for level 2 (n =548), from 0.0 to 21.63% with a random-effect model of 4.23% for level 3 (n =518), from 0.0 to 17.02% with a fixed-effect model of 0.39% for level 4 (n =310), and from 0.0 to 11.63% with a fixed-effect model of 1.7% for level 5 (n =417).

CONCLUSION

The rate of occult neck nodal metastasis in parotid malignancies is low, with neck level 2 the most commonly involved. The results of this meta-analysis prevented the authors from substantiating the appropriate extent of an END in parotid cancer.

Radiation-induced toxicities and outcomes after radiotherapy are independent of patient age in elderly salivary gland cancer patients: results from a matched-pair analysis of a rare disease

Purpose

This study analyzed survival and toxicity after (chemo)radiotherapy for primary salivary gland cancer patients aged ≥ 65 years and compared these results with younger patients using a matched-pair analysis.

Methods

Twenty-nine elderly patients with primary salivary gland carcinomas treated with (chemo)radiotherapy from 2008 to 2020 at University of Freiburg Medical Center were analyzed for oncological outcomes and therapy-associated toxicities. Local/locoregional control (LRC), progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan–Meier method, and the influence of clinical parameters on patient outcomes was assessed. A matched-pair analysis was performed after matching with patients < 65 years.

Results

Nine patients (31.0%) received definitive (chemo)radiotherapy, and 20 patients (69.0%) were treated in the adjuvant setting. 2-year LRC, PFS and OS ranged at 82.4%, 53.7% and 71.8%, respectively. Smoking (HR 3.980, p = 0.020), reduced performance status (HR 3.735, p = 0.016) and higher comorbidity burden (HR 4.601, p = 0.005) correlated with inferior OS. Using a matched-pair analysis with younger patients, elderly patients exhibited a trend towards reduced OS (HR 3.015, p = 0.065), but not PFS (HR 1.474, p = 0.371) or LRC (HR 1.324, p = 0.633). Acute and chronic grade 3 toxicities occurred in 31.0% and 12.5% of elderly patients, respectively, and the matched-pair analysis revealed no significant differences between age groups regarding treatment-related toxicities.

Conclusion

Treatment-related toxicities as well as LRC and PFS were comparable for salivary gland cancer patients undergoing radiotherapy. Therefore, concerns for more pronounced toxicities or reduced local/locoregional response rates should not guide treatment decisions in affected elderly patients.

Electronic supplementary material

The online version of this article (10.1007/s00405-020-06393-x) contains supplementary material, which is available to authorized users.

Does neck dissection affect post-operative outcomes in parotidectomy? A national study

OBJECTIVE

To characterize post-operative complications in parotidectomy with neck dissection.

METHODS

Patients age ≥ 18 receiving a parotidectomy or parotidectomy with neck dissection between 2005 and 2017 were eligible for inclusion. Patients with unknown demographic variables were excluded. Univariate and multivariable logistic regression analyses were performed.

RESULTS

A total of 13,609 parotidectomy patients were analyzed, 11,243 (82.6%) without neck dissection and 2366 (17.4%) with neck dissection. Both length of surgery (mean minutes ± standard deviation [SD] = 335.9 ± 189.2 vs. 152.9 ± 99.0, p < 0.001) and length of hospital stay (mean days ± SD = 3.90 ± 4.76 vs. 1.04 ± 2.14, p < 0.001) were greater with dissection. 13.9% of parotidectomies with neck dissection and 3.5% without dissection (p < 0.001) had at least one complication, which remained significant after multivariable adjustment (Odds Ratio[OR] = 1.565 (95%CI = 1.279-1.914), p < 0.001). The increase in post-operative complications was predominately driven by an increased transfusion rate (7.4% vs. 0.5%, p < 0.001). Multivariable analysis also demonstrated no significant difference in rates of returning to the operating room (OR = 1.122 (95%CI 0.843-1.493), p > 0.05) or rates of readmission (OR = 1.007 (95%CI 0.740-1.369), p > 0.05). Parotidectomy with neck dissection was more likely to be inpatient (OR = 4.411 (95%CI 3.887-5.004), p < 0.001) and to be ASA class 3 (OR = 1.367 (95%CI 1.194-1.564), p < 0.001).

CONCLUSIONS

Nationwide data demonstrates that parotidectomy with neck dissection is associated with increased rates of post-operative complications; however, neck dissection did not significantly impact readmission or reoperation rates. These findings indicate that neck dissection is a relatively safe addition to parotidectomy and provide novel evidence in the management of parotid malignancies.

Validated Prognostic Nomograms for Patients With Parotid Carcinoma Predicting 2- and 5-Year Tumor Recurrence-Free Interval Probability

Introduction: Salivary gland malignancies are rare tumors with a heterogenous histological and clinical appearance. Previously, we identified multiple prognostic factors in patients with parotid cancer and developed prognostic indices which have repeatedly been validated internationally, demonstrating their general applicability and lasting relevance. Recently, nomograms gained popularity as a prognostic tool. Thus, in this research we aimed to construct nomograms based on our previous validated prognostic models.

Material and Methods: Nomograms were constructed using the previously reported dataset of 168 patients with parotid cancer which was used to develop pre- and postoperative prognostic scores, PS1 and PS2, respectively. Concordance indices for PS1 and PS2 were previously estimated at 0.74 and 0.71, respectively, and are in line with other, widely accepted oncological nomograms.

Results: Pre- and postoperative nomograms predicting 2- and 5-year tumor recurrence-free survival probability are presented. All previously multivariately identified and validated prognostic factors, are incorporated (T size, N classification, pain, age at diagnosis, skin invasion, facial nerve dysfunction, perineural growth, and positive surgical margins). Examples of clinical application and interpretation are given.

Conclusions: The presented prognostic nomograms for predicting 2- and 5-year tumor recurrence-free probability in patients with parotid cancer are powerful, user-friendly, visual tools and are based on internationally validated prognostic indices. They allow for a reliable prognostic assessment and result in a more individualized estimate of the risk for recurrence than the prognostic grouping based on PS1 and PS2. This facilitates assigning trial-patients to risk groups, and may assist in therapeutic decision making and determining appropriate follow-up intervals in clinical practice.

Is There A Role for Limited Parotid Resections for Primary Malignant Parotid Tumors?

(1) Background: Lateral or total parotidectomy are the standard surgical treatments for malignant parotid tumors. However, some authors have proposed a more limited procedure. (2) Methods: We performed a review of the literature on this topic. Studies were included that met the following criteria: malignant parotid tumors, information about the extent of surgical resection, treated with less than a complete lateral lobectomy, and information on local control and/or survival. Nine articles fulfilled the inclusion criteria. (3) Results: Eight of the nine series reported favorable results for the more limited approaches. Most used them for small, mobile, low-grade cancers in the lateral parotid lobe. Most authors have used a limited partial lateral lobectomy for a presumed benign lesion. The remaining study analyzed pediatric patients treated with enucleation with poor local control. (4) Conclusions: There is weak evidence for recommending less extensive procedures than a lateral parotid lobectomy. In the unique case of a partial lateral parotidectomy performed for a tumor initially thought to be benign but pathologically proved to be malignant, close follow-up can be recommended for low grade T1 that has been excised with free margins and does not have adverse prognostic factors.