Determining the number of intraparotid lymph nodes: Postmortem examination

The differential diagnosis of lymphoepithelial lesion of the salivary gland

The differential diagnosis of salivary gland lesions with epithelial components and lymphoid stroma is often challenging. Salivary gland carcinoma with tumor-associated lymphoid proliferation, tumors composed of both epithelial and lymphoid components, lymphoid neoplasms in the salivary gland, and inflammatory lesions are all included in this category. It encompasses inflammatory lesions and neoplastic lesions. With the exception of Warthin tumors, these lesions are rare, making them more difficult to diagnose. Carcinoma showing thymus-like elements has recently been reported in the salivary gland. Similar to thymic carcinoma, tumor cells are positive for CD5 and are accompanied by T lymphocytes.

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.

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.

Frequency and malignancy rate of incidental focal salivary gland lesions identified by 18F-fluorodeoxyglucose-positron emission tomography

PURPOSE

We aimed to evaluate the frequency and malignancy rate of incidental salivary gland lesions (ISGLs) in patients undergoing 18F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT).

METHODS

Using a predefined algorithm, all descriptions of FDG-PET/CT scans performed in the North Denmark Region at the Department of Nuclear Medicine, Aalborg University Hospital from 1.12 2009 to 31.12 2019 were electronically searched for focal uptake in one or more salivary glands.

RESULTS

In total, 28,362 FDG-PET/CT scans were performed in the study period. ISGLs were found in 197 (0.7%). A total of 193 (98%) had parotid gland ISGL, and four (2%) had submandibular ISGL. No sublingual lesions were found. Ultimately, 117 patients (60%) were referred to the Department of Otorhinolaryngology-Head and Neck Surgery for evaluation. Fine needle aspiration biopsy was performed in 97 patients, and the most frequent cytopathology was Warthin's tumour (n = 62). Two patients had verified malignancy: one with histopathologically proven acinic cell carcinoma and one with cytopathologically proven metastasis from an oral squamous cell carcinoma.

CONCLUSIONS

Incidental salivary gland findings on FDG-PET/CT are rare, and the risk of malignancy is low. Patients with ISGL may be evaluated secondary to the primary disease, but special attention should be given to patients with prior or known head-and-neck malignancies and patients with symptoms from the salivary glands, including swelling.

Assessment of Parotid Gland Tumors by Means of Quantitative Multiparametric Ultrasound (mpUS)

OBJECTIVE

The preoperative diagnostical differentiation of parotid gland tumor (PGT) is not always simple due to several different entities. B-mode-ultrasound (US) remains the imaging modality of choice, while histopathology serves as the gold standard for finalizing the diagnosis. We aimed to evaluate the use of multiparametric US (mpUS) in the assessment of PGT.

METHODS

We included 97 PGTs from 96 patients. A standardized mpUS protocol using B-mode-US, shear-wave elastography (SWE), and standardized contrast-enhanced ultrasound (CEUS) was performed prior to surgical intervention. SWE was assessed by real-time measurement conducting a minimum of five measurements, while quantitative CEUS parameters were assessed with a post-processing perfusion software.

RESULTS

SWE allowed differentiation between benign PGT (Warthin's Tumor (WT) paired with lymph nodes (LN) and pleomorphic adenoma (PA)), and WT and LN were softer compared to PA. WT showed lower velocities than squamous cell carcinoma (SCC): the most common malignant PGT. CEUS parameters showed significant group differences between WT and PA, WT and malignant lesions, WT and SCC, WT paired with LN versus PA, and WT paired with LN versus SCC.

CONCLUSION

MpUS seems to be beneficial in the assessment of PGT characterization, with benign PGT appearing to be softer in SWE than tumors with malignant tendencies. The quantitative CEUS parameter shows higher perfusion in WT than in PA, and malignant PGTs are less vascularized than WTs.

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.

[Diagnostics and treatment of secondary malignancies of the parotid gland-An overview]

BACKGROUND

Secondary malignancies of the parotid gland frequently have a cutaneous origin and the incidence in central Europe is increasing.

OBJECTIVE

The aim of this review article was to present the epidemiology, (differential) diagnostics and treatment of secondary malignancies of the parotid gland.

MATERIAL AND METHODS

A literature search of the current guidelines and evidence was carried out in the web-based databank PubMed.

RESULTS

The incidence of secondary malignancies of the parotid gland seems to be increasing in Europe, mainly due to a rising incidence of metastases of cutaneous squamous cell carcinomas. Except for malignant lymphomas, parotidectomy is the treatment of choice in the curative situation. In the absence of clear evidence, in the case of an intact facial nerve lateral or total parotidectomy with ipsilateral neck dissection seems to be indicated, depending on the entity of the secondary malignancy.

CONCLUSION

The differential diagnostics of squamous cell carcinoma (in) of the parotid gland can be complicated. When a squamous cell carcinoma of the parotid gland is diagnosed for the first time, a dermatological full body examination and a detailed medical history should be taken with respect to skin tumors of the head and neck region. In addition to surgical treatment of the parotid gland and neck, adjuvant radiotherapy is usually indicated.

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.

Conventional, diffusion, and dynamic contrast-enhanced MRI findings for differentiating metaplastic Warthin's tumor of the parotid gland

The purpose of this study was to explore conventional, diffusion, and dynamic contrast-enhanced MRI (DCE-MRI) characteristics for differentiating metaplastic Warthin's tumor (MWT) from other tumor types of the parotid gland, including non-metaplastic Warthin's tumor (non-MWT), pleomorphic adenoma (PA), and malignant tumor (MT). A total of 178 patients with histologically proven tumors of the parotid gland, including 21 MWTs, 49 non-MWTs, 66 PAs, and 42 MTs, were enrolled in the study. Conventional MRI was performed in all patients. One hundred and fifty patients had preoperative diffusion-weighted MR imaging (DWI), and 62 patients had preoperative DCE-MRI. The differences in the conventional, DCE-MRI, and DWI records between MWTs and the other three tumor types were statistically evaluated. Compared with non-MWTs and PAs, there was a statistically significant difference in circumscription (p < 0.01). The ill-defined circumscription was more common in MWTs than non-MWTs and PAs. Compared with PAs, there was a statistically significant difference in morphology (p < 0.05). The lobulated morphology was more common in PAs than MWTs. Compared with PAs and MTs, there was a statistically significant difference in the T2 signal of the solid component (p < 0.01). The T2 moderate intensity of solid components was more common in MWTs than PAs and MTs. The solid components of PAs mostly showed hyperintense on T2-weighted imaging. Cyst/necrosis was more common in MWTs than PAs and MTs. Hyperintense of cyst/necrosis was more common in MWTs and non-MWTs. With respect to contrast enhancement, 52.4% MWTs exhibited moderate or marked enhancement, and most non-MWTs (81.6%) exhibited mild enhancement. Most PAs (84.8%) exhibited marked enhancement. The mean ADC value of MWTs (0.94 × 10-3 ± 0.11 mm2/s) was significantly lower than that of the PAs (1.60 × 10-3 ± 0.17 mm2/s) (p < 0.001). On DCE-MRI, six of eight MWTs demonstrated TIC of type B. Although MWT is rare, conventional MRI characteristics, DWI and DCE-MRI can provide useful information for differentiating MWT from other parotid mass.

Intra-parotid lymph node metastasis in patients with non-cutaneous head and neck cancers: clinical and imaging features for differentiation from simultaneous parotid primary tumor

BACKGROUND

Although uncommon, intra-parotid lymph node (IPLN) metastasis should be considered in the differential diagnosis of parotid masses in patients with head and neck cancers.

PURPOSE

To compare the clinical and imaging features of IPLN metastases from head and neck cancers and simultaneous parotid primary tumors.

MATERIAL AND METHODS

A retrospective review of 2199 patients with non-parotid head and neck cancers revealed 63 patients who also underwent parotidectomy during curative resection of head and neck cancer. After exclusion of direct extension to the parotid gland from adjacent primary tumors (n = 12) and IPLN metastases from skin cancer (n = 5), the final study group was composed of 46 patients, including 26 (1.2%) with 33 IPLN metastases and 20 (0.9%) with 24 simultaneous parotid primary tumors. We compared clinical features of patients (sex, age, site of primary tumor, histologic type, history of prior treatment for malignancy, TNM stages, side of parotid lesion, multiplicity, and metastasis in ipsilateral cervical LNs) and the CT (location in parotid gland, maximum dimension, margins, and central necrosis or cystic change) and 18F-FDG PET/CT (maximum standardized uptake value) findings.

RESULTS

Ipsilateral level II LN metastasis was more frequent in the IPLN metastasis group than in the simultaneous parotid primary tumor group (73.1% vs. 35.0%, P < 0.05). Imaging features such as location in parotid gland, maximum dimension, margins, central necrosis or cystic change, and maximum standardized uptake value showed no significant differences between the two groups.

CONCLUSION

CT and PET/CT findings of IPLN metastasis are indistinguishable from simultaneous parotid primary tumor in patients with head and neck cancers.

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.

Surgical anatomy of the lymphatic drainage of the salivary glands: a systematic review

BACKGROUND

Nodal metastasis in salivary gland malignancies has important clinical implications; a good understanding of their complex anatomy is paramount to the head and neck surgeon.

METHODS

A contemporary and comprehensive literature review was conducted of the lymphatic drainage of the salivary glands, with special emphasis on its surgical applications.

RESULTS

The parotid gland has extraglandular and intraglandular nodes acting as a single functional drainage unit. Intraglandular parotid notes are unique to the parotid gland, and consist of a larger superficial group and a smaller deep group. The presence of intraglandular submandibular nodes, as described by early anatomists, is much debated nowadays. The sublingual glands drain to the lingual lymph nodes, which are divided into median, intermediate and lateral groups.

CONCLUSION

This review highlights the complex arrangements of lymph nodes draining the salivary glands. It may provide a valid anatomical explanation for the nodal metastasis patterns commonly seen in salivary gland malignancy.

Determining the number and distribution of intraparotid lymph nodes according to parotidectomy classification of European Salivary Gland Society: Cadaveric study

BACKGROUND

To investigate the distribution of the parotid gland's intraglandular lymph nodes using the parotidectomy zones determined by the parotidectomy classification of the European Salivary Gland Society (ESGS).

MATERIALS AND METHODS

A total of 128 parotid glands were dissected from 64 fresh cadavers, by bilateral parotidectomy without additional incision within the standard autopsy procedure, and categorized.

RESULTS

Eighty-six percent of the IGLNs were located in the superficial lobe and 14% in the deep lobe. An average of 7.09 ± 3.55 IGLNs were found for each of the gland; there were 6.11 ± 3.28 in the superficial lobe and 0.98 ± 1.46 in the deep lobe. While the most common lymph nodes were found in level 2 with 47.7%, only 5% of IGLNs were at level 4. According to the proposed modification, the most common lymph nodes (35.24%) were located at level 2B.

CONCLUSION

Level 2B was found to contain significantly more lymph nodes than other levels, which has not been evaluated before in literature.

Role of intraparotid node metastasis in mucoepidermoid carcinoma of the parotid gland

BACKGROUND

Prognostic factors for parotid mucoepidermoid carcinoma (MEC) usually include disease grade, tumor stage, node stage, perineural invasion, and lymphovascular invasion. But the role of intraparotid nodes (IPNs) remains unclear, therefore, the study aimed to analyze the significance of IPNs in predicting recurrence in parotid MEC.

METHODS

One hundred and ninety patients were included for analysis finally. Data regarding demography, pathological characteristics, IPN metastasis, TNM stage, follow up was collected and evaluated. The recurrence-free survival (RFS) was the main study endpoint.

RESULTS

A total of 47 (24.7%) patients had IPN metastasis, and the IPN metastasis was significantly related to tumor stage, pathologic N stage, lymph-vascular invasion, perineural invasion, and disease grade. Recurrence occurred in 34 (17.9%) patients. For patients without IPN metastasis, the 10-year RFS rate was 88%, for patients with IPN metastasis, the 10-year RFS rate was 54%, the difference was significant (p < 0.001). Further Cox model analysis confirmed the independence of IPN metastasis in predicting the prognosis.

CONCLUSION

The IPN metastasis is relatively common in parotid MEC, it is significantly related to tumor stage and disease grade, IPN metastasis means worse recurrence-free survival.