Patterns of lymph node metastasis and their influence on outcomes in patients with submandibular gland carcinoma

Lymph node surgery for salivary gland cancer: REFCOR recommendations by the formal consensus method

OBJECTIVE

To determine the indications for neck dissection in the management of parotid, submandibular or minor salivary gland cancers depending on the clinical situation: i.e., clinical lymph node involvement (cN+) or not (cN0); low or high risk of occult nodal metastasis; diagnosis of malignancy before, during or after surgery.

MATERIAL AND METHODS

The French Network of Rare Head and Neck Tumors (REFCOR) formed a steering group which drafted a narrative review of the literature published on Medline and proposed recommendations. The level of adherence to the recommendations was then assessed by a rating group according to the formal consensus method.

RESULTS

In cN+ salivary gland cancer, ipsilateral neck dissection is recommended. In cN0 salivary gland cancer, ipsilateral neck dissection is recommended, except for tumors at low risk of occult nodal metastasis. If definitive pathology reveals a high risk of occult nodal involvement, additional neck treatment is recommended: ipsilateral neck dissection or elective nodal irradiation.

CONCLUSION

The rate of occult lymph node involvement, and therefore the indication for elective neck dissection, depends primarily on the pathologic grade of the salivary gland cancer.

Incidence and spread pattern of lymph node metastasis from submandibular gland cancer

OBJECTIVES

To clarify the indication of neck dissection (ND) for patient with submandibular gland (SMG) cancer.

METHODS

A total of 43 patients with SMG cancer were retrospectively analyzed. Forty-one patients underwent ND: Levels I-V in 19 patients, Levels I-III in 18 patients, and Level Ib in 4 patients. The other two patients did not undergo ND, since preoperative diagnoses were benign. Postoperative radiotherapy was performed in 19 patients with positive surgical margin, high grade cancer or stage IV disease.

RESULTS

LN metastases were pathologically confirmed in all patients with cN + and 6 out of 31 patients with cN-. No patients developed regional recurrence during follow-up periods. Ultimately, LN metastases were pathologically confirmed in 17 of 27 high grade, one out of 9 intermediate grade, but not in 7 low grade.

CONCLUSIONS

Prophylactic neck dissection should be considered in T3/4 and high grade SMG cancers.

Epidemiology, outcomes, and prognostic factors in submandibular gland carcinomas: a national DAHANCA study

PURPOSE

The aim of this study is to present incidence, histological subtypes, survival rates, and prognostic factors based on a national cohort of patients with salivary gland carcinoma.

METHODS

All Danish patients with submandibular gland carcinoma diagnosed from 1990 to 2015 (n = 206) were included and analyzed following histological re-evaluation. Data were collected by the Danish Head and Neck Cancer Group (DAHANCA). Overall, disease-specific and recurrence-free survival were evaluated. Prognostic factors were analyzed with multivariate Cox Hazard Regression.

RESULTS

The study population consisted of 109 (53%) men and 97 (47%) women, median age 62 years (range 11-102). Adenoid cystic carcinoma was the most frequent subtype (50%). Tumour classification T1/T2 (75%) and N0 (78%) was most frequent. The mean crude incidence was 0.17/100,000/year. Most patients (n = 194, 94%) were treated with primary surgery, and 130 (67%) received postoperative radiotherapy. The 5- and 10-year survival rates were for overall survival 64% and 41%, disease-specific survival 74% and 61%, and recurrence-free survival 70% and 56%, respectively. Survival rates were higher for adenoid cystic carcinoma compared to other subtypes, but the difference was not significant in multivariate analysis. Recurrence occurred in 69 patients, and 37 (53.6%) of them had recurrence in a distant site. Advanced T-classification and regional lymph-node metastases had significant negative impact on survival rates.

CONCLUSION

The incidence of submandibular gland carcinoma in Denmark was 0.17/100,000/year and stable during the time period. The most frequent subtype was adenoid cystic carcinoma. Half of the recurrences presented in a distant site, and multivariate analysis confirmed that advanced stage was independent negative prognostic factor for recurrence and survival.

Salivary gland cancer: ESMO-European Reference Network on Rare Adult Solid Cancers (EURACAN) Clinical Practice Guideline for diagnosis, treatment and follow-up

•This ESMO–EURACAN Clinical Practice Guideline provides key recommendations for managing salivary gland cancer. •The guideline covers clinical and pathological diagnosis, staging and risk assessment, treatment and follow-up. •Treatment algorithms for parotid, submandibular, sublingual and minor salivary gland cancer are provided. •The author group encompasses a multidisciplinary group of experts from different institutions and countries in Europe. •Recommendations are based on available scientific data and the authors’ collective expert opinion.

The rate of occult nodal metastasis in submandibular gland malignancies: A case series and meta-analysis

OBJECTIVE

Submandibular gland (SMG) malignancies are exceedingly rare. Lymph node metastasis is one of the most important determinants of outcome in SMG malignancies. The aim of this study was to investigate the overall rate of occult neck nodal metastasis in SMG malignancies.

STUDY DESIGN

The study design is a meta-analysis of all studies on patients with a primary SMG malignancy, without evidence of neck nodal metastasis, who underwent an elective neck dissection (END). The search strategy identified 158 papers that appeared in print from January 1980 to July 2020. All eligible patients from the Tel-Aviv Medical Center were analyzed and consolidated into a case series. A total of 12 retrospective studies that included 306 suitable patients met inclusion criteria.

RESULTS

The risk for occult metastasis in primary SMG malignancies was 0.0% to 50.0%, with a fixed effect model of 19.52% (95% CI, 14.9%-24.5%). The analyzed studies included a wide range of pathologies. The most common malignancies were adenoid cystic carcinoma and mucoepidermoid carcinoma.

CONCLUSIONS

The overall rate of occult neck metastasis in SMG malignancies is relatively high, and an END should be the default intervention in these cases. An END is unwarranted in tumors judged clinically to be low stage and low grade.

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.

Diagnostic value of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography in sublingual and submandibular salivary gland tumors

The aim of the present study was to compare the diagnostic accuracy of fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) with that of conventional imaging studies (CIS), such as CT or magnetic resonance imaging (MRI), in the clinical diagnosis and staging of submandibular and sublingual salivary gland tumors. In addition, the data obtained were used to evaluate the significance of maximum standardized uptake value (SUVmax) in diagnosing benign or malignant lesions. For the present study, 18 patients with submandibular or sublingual neoplasms underwent F-18 FDG PET/CT imaging with accompanying CT or MRI. The diagnostic values from 43 F-18 FDG PET/CT scans and 28 CIS of the 18 patients were compared to the gold standard histopathological and/or cytopathological diagnosis. The results demonstrated that the diagnostic accuracy for predicting primary tumors was similar between F-18 FDG PET/CT and CIS. By contrast, PET/CT imaging was more accurate in detecting lymph node metastasis compared with CT or MRI (95.4 vs. 66.7%). F-18 FDG PET/CT had a sensitivity of 88.9% and a specificity of 97.1%, whereas CT or MRI had a sensitivity of 54.5% and a specificity of 75.0%. F-18 FDG PET/CT also enabled screening for distant metastasis, as observed in 10 cases in the present study. Furthermore, there were no significant differences in SUVmax between benign or malignant salivary gland lesions, as high glucose metabolism was also observed in benign tumors. In conclusion, F-18 FDG PET/CT provides more accurate diagnostic information for the evaluation of submandibular and sublingual salivary gland tumors as compared with CIS in terms of lymph node and distant metastasis.

Submandibular gland cancers: prognostic factors and survival analysis

PURPOSE

The aim of this study is to evaluate prognosis and prognostic factors affecting oncological outcome.

METHODS

Records of the subjects managed for a submandibular gland cancer (SGC) between January 1997 and June 2014 were retrospectively reviewed. Survival outcomes were analyzed. All subjects had a minimum follow up of 5 years or until death.

RESULTS

Of 24 subjects (13 male, 11 female), 16 (64.6%) were adenoid cystic carcinoma (ACC). Eight patients had clinically positive neck nodes and 2 of the 16 clinically negative necks were also positive histologically. None of the subjects had distant metastases at presentation. The Kaplan-Meier 5-year estimated locoregional control (LRC), distant metastasis free survival (DMFS), disease free survival (DFS) and overall survival (OS) were 62.5%, 83.3%, 58.3% and 66.7%, respectively. American Joint Committee on Cancer (AJCC) overall stage and extra glandular extension (EGE) proved to be significant predictors of LRC. Only smoking was found to be a significant factor related with lower DMFS and only EGE significantly lowered DFS. Positive nodal stage and positive surgical margin were proved to be significant predictors of OS.

CONCLUSION

Surgery alone is effective in subjects with early stage, noninvasive and low-grade cancers. Despite aggressive treatment, locoregional recurrence was common in subjects who were at advanced stage.

Nodal failure patterns and utility of elective nodal irradiation in submandibular gland carcinoma treated with postoperative radiotherapy - a multicenter experience

BACKGROUND

The patterns of nodal relapse in submandibular gland carcinoma (SMGC) patients treated with postoperative radiotherapy (PORT) remain unclear. This study aims to investigate the nodal failure patterns and the utility of elective nodal irradiation (ENI) in SMGC patients undergoing PORT.

METHODS

We retrospectively enrolled 65 SMGC patients who underwent PORT between 2000 and 2014. The nodal failure sites in relation to irradiation fields and pathological parameters were analyzed. ENI regions were categorized into three bilateral echelons (first, levels I-II; second, level III; and third, levels IV-V). Extended ENI was defined as coverage of at least the immediately adjacent uninvolved echelons bilaterally; otherwise, limited ENI was administered.

RESULTS

Thirty patients (46%) were stage III-IV, and 18 (28%) were pN+. Neck irradiation included limited (72%) and extended ENI (28%). With a median follow-up of 79 months, 11 patients (17%) developed nodal failures (ipsilateral, N = 6; contralateral, N = 7), 7 (64%) of whom relapsed in the adjacent uninvolved echelons. We identified pN+ (P = 0.030), extranodal extension (ENE, P = 0.002), pT3-4 (P = 0.021), and lymphovascular invasion (LVI, P = 0.004) as significant predictors of contralateral neck recurrence. Extended ENI significantly improved regional control (RC) in patients with pN+ (P = 0.003), ENE (P = 0.022), pT3-4 (P = 0.044), and LVI (P = 0.014), and improved disease-free survival (DFS) in patients with pN+ (P = 0.034). For patients with ≥2 coincident adverse factors, extended ENI significantly increased RC (P < 0.001), distant metastasis-free survival (P = 0.019), and DFS (P = 0.007); conversely, no nodal recurrence was observed in patients without these adverse factors, even when only the involved echelon was irradiated.

CONCLUSIONS

Nodal failure is not uncommon in SMGC patients treated with PORT if pN+, ENE, pT3-4, and LVI are present. Extended ENI should be considered, particularly in patients with multiple pathological adverse factors.

Submandibular gland cancer: Specific features and treatment considerations

BACKGROUND

In the absence of unified treatment protocol, we evaluated the management and outcomes of submandibular gland cancers in an unselected patient series.

METHODS

We included all patients with resected submandibular gland cancer treated at the Helsinki University Hospital from 2000 to 2010 with a 5-year minimum follow-up.

RESULTS

Twenty-five patients with cancer represented 30% of submandibular gland neoplasms, and most were adenoid cystic carcinomas (ACCs; 56%). At presentation, 3 patients showed clinical signs of probable malignancy. Of 22 neck dissection specimens, 5 patients (20%) had metastases with an occult metastasis rate of 4%. Cancer recurred in 11 patients (44%), of which 7 (28%) were only at a distant site. The 5-year disease-specific survival (DSS) and overall survival (OS) rates were 76%, and disease-free survival (DFS) was 68%.

CONCLUSION

Most tumors were ACCs differing from the histological pattern of parotid gland cancers. Occult metastases were rare. The rarity of submandibular gland cancer, its variable histological pattern, and varying biological behavior warrant centralized management.

Preoperative evaluation and surgical planning of submandibular gland tumors

BACKGROUND

Roughly half of submandibular gland neoplasms are malignant. Because preoperative information on the nature of these tumors remains limited, both preoperative evaluation and assessment of the extent of primary surgery warrant guidelines that are more accurate.

METHODS

We evaluated the preoperative examinations and management of all submandibular gland neoplasms treated surgically at the Helsinki University Hospital between 2000 and 2010.

RESULTS

Of the 83 tumors, 58 (70%) were benign and 25 (30%) were malignant. Of the benign tumors, 54 (93%) were pleomorphic adenomas. The cytology in 8 patients (10%) was class IV or V, and in 12 patients was class III; the tumors in 9 of these 12 patients turned out to be malignant. Of all malignancies, 10 (40%) required additional more extensive surgery.

CONCLUSION

Ultrasound-guided fine-needle aspiration cytology (FNAC) proved useful, with limitations, in preoperative examination. Surgeons should always obtain wide margins whenever possible, even when clinical means or cytology indicates no malignancy. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1071-1077, 2017.

Cervical lymph node metastasis in adenoid cystic carcinoma of the major salivary glands

Objective:

To verify the prevalence of cervical lymph node metastasis in adenoid cystic carcinoma of major salivary glands, and to establish recommendations for elective neck treatment.

Methods:

A search was conducted of the US National Library of Medicine database. Appropriate articles were selected from the abstracts, and the original publications were obtained to extract data.

Results:

Among 483 cases of major salivary gland adenoid cystic carcinoma, a total of 90 (18.6 per cent) had cervical metastasis. The prevalence of positive nodes from adenoid cystic carcinoma was 14.5 per cent for parotid gland, 22.5 per cent for submandibular gland and 24.7 per cent for sublingual gland. Cervical lymph node metastasis occurred more frequently in patients with primary tumour stage T3–4 adenoid cystic carcinoma, and was usually located in levels II and III in the neck.

Conclusion:

Adenoid cystic carcinoma of the major salivary glands is associated with a significant prevalence of cervical node metastasis, and elective neck treatment is indicated for T3 and T4 primary tumours, as well as tumours with other histological risk factors.

Comparison of adenoid cystic carcinomas arising from the parotid gland vs. the submandibular gland: focus on systemic metastasis and tumor-associated blood vessels

BACKGROUND

Although several studies reported that distant metastasis occurs more frequently in the tumors of submandibular gland (SMG) than parotid gland (PG), why SMG tumors preferentially metastasize to distant organs is not fully understood. We aimed to identify the differential tumor microenvironment for distant metastasis and possible underlying mechanisms.

METHODS

We retrieved 27 cases of 1-4-cm-sized adenoid cystic carcinomas (ACCs) arising from the PG (n = 12) and SMG (n = 15). c-KIT, VEGF-R2, and CD31 staining were quantified by image-based analysis to define the positive expression or tumor-associated vessel areas in two representative sections per case. In addition, angiogenesis-related genomic expression profiling was carried out to explore the underlying mechanism, which was confirmed by RT-PCR and immunohistochemistry.

RESULTS

Earlier systemic dissemination within 2 years was detected exclusively in SMG ACCs (5/15). The area of tumor-associated blood vessels was larger in SMG ACCs than PG ACCs, and ACCs showing distant metastasis had greater blood vessel area than those without metastasis. Interestingly, normal SMG had more blood vessels per area than PG. Among angiogenesis-related signals, the level of IL-6 was significantly lower in SMG ACCs than PG ACCs. Moreover, IL-6 expression decreased significantly in SMG ACCs compared with that in normal SMG, whereas it was up-regulated in PG ACCs.

CONCLUSION

ACCs in the SMG microenvironment have more abundant tumor-associated blood vessels than PG ACCs, which may explain the higher risk of distant metastasis from SMG tumors.

Prognostic implications of node metastatic features in OSCC: a retrospective study on 121 neck dissections

Lymph node metastases are responsible for shorter survival in oral squamous cell carcinoma (OSCC). The aim of the present study was to assess the node metastasis frequency and survival according to the node metastasis features in 121 neck dissections (NDs) performed for OSCC, identifying evidence-based correlations and contrasts with previous literature. The retrospective study involved 121 patients affected by OSCC who had undergone modified radical ND (MRND) for therapeutic, elective reasons or after intraoperative positivity to metastasis of sentinel lymph nodes (SLN+). Node metastasis frequency and behaviour (typical vs. atypical) and their number and distribution according to pre-surgical cTNM cancer staging were considered and overall survival Kaplan-Meier curves were calculated for each group in order to compare mortality according to ND type (elective, therapeutic, after SLN+), lymph node metastatic pattern (typical or atypical), size (micrometastasis vs. macrometastasis) and number. Results showed statistically significant different overall survival according to pre-surgical staging, number of lymph nodes harvested and intent to surgery. Sentinel lymph node resulted in the sole positive node affected by metastasis in small cT1- cT2/cN0 OSCC and an ND subsequent to its positivity during intraoperative assessment may be considered an overtreatment.