Lymphoepithelial Carcinoma of Salivary Glands

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.

Lymphoepithelial carcinoma of the parotid gland

Primary lymphoepithelial carcinoma of the salivary glands is an exceptional oncological condition that predominantly emerges within the parotid gland. A significant prevalence of lymphoepithelial carcinoma has been reported in the Inuit population, along with an associated positive serology for Epstein-Barr virus in these endemic regions. In this paper, we present a case of primary lymphoepithelial carcinoma of the parotid gland in a 68-year-old female patient with a history of diabetes and hypertension residing in a non-endemic area. Histology plays a critical role in the definitive diagnosis, and confirming the primary origin of lymphoepithelial carcinoma after ruling out metastasis from undifferentiated nasopharyngeal carcinoma. The mainstay of treatment is a combination of surgical resection and adjuvant radiotherapy. Inoperable forms are typically managed with chemoradiotherapy.

Lymphoepithelial Carcinoma of the Sublingual Gland: A Case Report

Lymphoepithelial carcinoma (LEC) of the salivary gland is a rare squamous cell carcinoma. LEC commonly presents in the parotid and submandibular glands and rarely in the sublingual gland. While salivary gland LEC has a predilection for Inuit-Yupik and Chinese populations, few cases have been reported in the Hispanic population and none for sublingual glands in the English language literature. Here, we present the seventh case report in the English language literature for sublingual LEC and the first case observed in a Hispanic patient.

A case of metastatic lymphoepithelial carcinoma of parotid gland identified on 68gallium DOTA-[Tyr3] octreotate PET CT

The authors present the case of a 59-year-old lady diagnosed with lymphoepithelial carcinoma (LEC) of the left parotid gland. The primary tumour was identified using contrast-enhanced CT, and diagnosis was confirmed via fine needle aspiration cytology and immunohistochemistry. Staging using fluorine-18 fluorodeoxyglucose PET CT revealed regional nodal metastases, while no distant metastasis was evident. Following radical radiotherapy, a favourable locoregional response was observed on MRI, yet the patient's plasma Epstein-Barr virus load continued to rise. Given her primary tumour's somatostatin receptor type 2 (SSTR2) positivity, gallium-68 DOTA-[Tyr3] octreotate PET CT (68Ga-DOTATATE PET CT) was performed, revealing multiple distant metastases with DOTATATE avidity. Despite attempts at palliative chemotherapy and immunotherapy, disease progression led to the decision for the best supportive care. The unique presentation of metastatic LEC on 68Ga-DOTATATE PET CT suggests a potential role for SSTR2-targeted imaging in diagnosis and management.

Magnetic Resonance Imaging Findings of Lymphoepithelial Carcinoma of the Submandibular Gland: A Case Report

Lymphoepithelial carcinoma (LEC) is an uncommon neoplasm strongly associated with Epstein-Barr virus (EBV). LEC of the salivary glands (LECSG) is very rare: the most commonly affected site is the parotid gland, followed by the submandibular gland. This report describes the case of a 58-year-old man who presented with a left submandibular mass that had gradually increased in size over five years. On magnetic resonance imaging (MRI), the mass showed low apparent diffusion coefficient (ADC) values, rapid initial enhancement before reaching a plateau on dynamic contrast-enhanced MRI (DCE-MRI), and internal septal-like enhancement. Histopathologically, the tumor comprised polygonal or round tumor cells with atypical or pleomorphic nuclei and numerous lymphocytes, separated by heavy fibrosis. Immunohistological findings were positive for AE/AE3, CD20, and EBV-encoded small RNA in situ hybridization (EBER-ISH), consistent with LEC. A low ADC value with rapid initial enhancement before reaching a plateau on DCE-MRI was thought to reflect abundant cellular components with tumor neoangiogenesis, whereas internal septal-like enhancement reflects separating heavy fibrosis. To the best of our knowledge, this is the first case report describing ADC value and DCE-MRI findings of LECSG, and these findings can be considered characteristic MRI findings of LECSG.

68 Ga-DOTATATE PET/CT of Metastatic Lymphoepithelial Carcinoma of Parotid Gland

ABSTRACT

We present a case of a 59-year-old woman with lymphoepithelial carcinoma of left parotid gland. She was treated with radical radiotherapy, but her plasma Epstein-Barr virus DNA load continued to increase despite good locoregional response. As her primary tumor was positive for somatostatin receptor type 2, we performed 68 Ga-DOTATATE PET/CT, which revealed multiple DOTATATE-avid distant metastases.

Challenging Tumor Heterogeneity with HER2, p16 and Somatostatin Receptor 2 Expression in a Case of EBV-Associated Lymphoepithelial Carcinoma of the Salivary Gland

BACKGROUND

Lymphoepithelial carcinoma of the salivary glands (LECSG) is a rare disease in the Western hemisphere that is typically associated with an EBV infection. The molecular mechanisms of LECSG tumorigenesis are poorly understood.

RESULTS

Here we report a case of EBV-associated LECSG with an unusual immunophenotype. The tumor exhibited bi-morphic histological features with a mutually exclusive expression of HER2 and p16. The p16-positive domain of the tumor immunohistochemically co-expressed late membrane protein 1 (LMP-1), while the HER2 positive domain did not. Both tumor regions expressed SSTR2.

METHODS

In situ hybridization confirmed the EBV origin of the tumor while extensive immunohistochemical characterization and the recently established RNA-based next generation sequencing panel ("SalvGlandDx" panel) did not reveal evidence for another salivary gland neoplasm. No HPV co-infection was detected by in situ hybridization or PCR-based screenings and no ERBB2 gene amplification was detected by fluorescence in situ hybridization.

CONCLUSION

These findings suggest tumor heterogeneity and lack of genomic aberrations in EBV-associated LECSGs. The heterogenous and unusual immunohistochemical features explain the diagnostic difficulties and simultaneously extend the immunophenotype spectrum of this tumor entity.

The role of postoperative radiotherapy (PORT) in lymphoepithelial carcinoma of the salivary gland (LECSG) and the effect of postoperative EBV DNA on prognosis

BACKGROUND

Whether postoperative radiotherapy (PORT) could improve survival and the role of EBV DNA remains unclear for patients with lymphoepithelial carcinoma of the salivary glands (LECSG).

PATIENTS AND METHODS

360 patients were included. Independent prognostic factors were selected using a Cox proportional hazards model and incorporated into risk stratification.

RESULTS

The number of positive lymph nodes (PLNs) ≥ 3 and tumor size ≥ 3 cm were independent factors for PFS in patients with neck dissection (ND). Patients were divided into three groups: high-risk, size ≥ 3 cm&PLNs ≥ 3; intermediate-risk, size < 3 cm&PLNs ≥ 3 or size ≥ 3 cm&PLNs < 3; low-risk, size < 3 cm&PLNs < 3. The 5-year PFS rate of the low-, intermediate- and high-risk patients receiving non-PORT and PORT was 87.9% vs 93.5% (p = 0.12), 41.2% vs 81.1% (p < 0.001), 18.0% vs 51.1% (p = 0.034). N stage was an independent factor for PFS in patients with non-neck dissection (NND) and patients were divided into two groups: low-risk, N0; and high-risk, N1/2. The 5-year PFS rate of the low-risk, and high-risk patients receiving non-PORT and PORT was 77.9% vs 94.3% (p = 0.0019), 21.4% vs 71.3% (p = 0.015). Compared with EBV DNA = 0, the 5-year PFS rate of patients with EBV DNA > 0 was 19.9% vs 91.3% (p < 0.001). In patients with EBV DNA = 0, the 5-year PFS rate of patients with or without PORT was 95.1% vs 92.3% (p = 0.082); while in patients with EBV DNA > 0, the 5-year PFS rate was 37% vs 9.2% (p = 0.0056).

CONCLUSIONS

In patients with ND, PLNs < 3&size < 3 cm patients did not benefit from PORT. Detectable EBV DNA after surgery was a negative prognostic factor.

Intraoral salivary lymphoepithelial carcinoma: clinicopathologic and immunophenotypic characterization of 3 cases indicates elevated programmed death-ligand 1 expression

OBJECTIVE

Intraoral salivary lymphoepithelial carcinoma (ISLEC) is a rare malignancy with programmed death-ligand 1 (PD-L1) expression levels that have been greatly understudied. We examined the clinicopathologic and immunophenotypic characteristics, including PD-L1 levels, of 3 cases of ISLEC.

STUDY DESIGN

We searched the archives of 2 oral and maxillofacial pathology laboratories for specimens diagnosed as ISLEC between 1985 and 2022. We collected patient demographic and clinical data. Immunostaining for AE1/AE3, CK7, CD3, CD20, p16, p53, Ki67, and PD-L1 (SP263), as well as Epstein-Barr virus-encoded small RNAs (EBER) in situ hybridization (ISH) were performed.

RESULTS

All 3 cases affected males aged 42 to 84 years (median = 61y) and involved the floor of the mouth, soft palate/uvula, and tongue. The lesions showed diffuse infiltration by non-keratinizing sheets and islands of undifferentiated carcinoma cells with associated dense lymphoplasmacytic inflammation. Immunohistochemically, all tumors showed AE1/AE3 positivity, selective p53 staining, and negativity for CK7 and p16. Ki67 highlighted 20%-80% of lesional cells. The inflammatory infiltrate comprised a mixed population of T and B lymphocytes. EBER ISH was positive in one case. All ISLECs displayed membranous, focal-to-diffuse, PD-L1 staining with tumor proportion score > 95% in two and 40-50% in the third case.

CONCLUSIONS

The clinicopathologic and immunophenotypic characteristics of the cases we examined highlight the rarity of ISLEC and indicate overall high PD-L1 levels in this type of malignancy, rendering patients with ISLEC potential candidates for targeted α-PD-1/PD-L1 immunotherapy.

Is radical radiotherapy with/without surgery an effective treatment in the lymphoepithelial carcinoma of the salivary gland？

BACKGROUND

There is limited information of radical radiotherapy (RT) on lymphoepithelial carcinoma of salivary gland (LECSG) regarding to the rarity of the disease. We conducted this retrospective study that evaluated the feasibility and efficacy of radical RT with/without surgery in LECSG.

METHODS

We retrospectively reviewed patients that were pathologically diagnosed of LECSG and had definite or suspicious residual disease. The prescribed dose given to P-GTV and/or P-GTV-LN was 66 to 70.4 Gy. The clinical target volume (CTV) involved ipsilateral salivary gland and corresponding lymph node drainage area.

RESULTS

A total of 56 patients were included. With a median follow-up of 60 months (range: 8 to 151 months), the 1-, 5-, and 10-year progression-free survival (PFS) rates were 94.6%, 84.7% and 84.7%; locoregional progression-free survival (LRPFS) rates were 98.2%, 87.4% and 87.4%; distance metastasis-free survival (DMFS) rates were 94.6%, 86.7% and 86.7%; and overall survival (OS) rates were 98.2%, 92.4% and 89.0%, respectively. A total of 7 patients without surgery were included. All patients were alive and only one patient experienced failure of distant metastasis four months after RT. The results of univariate analysis showed that compared with N stage, the number of positive lymph nodes (2 positive lymph nodes) was better prognostic predictor especially in PFS. There were no treatment-related deaths and most toxicities of RT were mild.

CONCLUSIONS

Radical RT with/without surgery in LECSG for definite or suspicious residual disease is feasibility and efficacy. Most toxicities of RT were mild due to the target volume involved ipsilateral area.

Lymphoepithelial Carcinoma of the Breast Treated With Partial Mastectomy and Sentinel Lymph Node Biopsy

Lymphoepithelial carcinoma of the breast (LELC) is a rarely encountered form of breast carcinoma, and there is limited information treatment for this entity. We present a case of a 55-year-old postmenopausal female presenting with a left breast mass on screening mammogram with core needle biopsy showing lymphoepithelial carcinoma. The patient was treated with surgical resection of the mass and sentinel lymph node biopsy, followed by adjuvant chemotherapy and radiation. Given the rarity of this type of breast carcinoma, our case study continues to add to the treatment considerations in the literature, specifically the role of sentinel lymph node.

Epstein‑Barr virus‑associated lymphoepithelial carcinoma arising in the parotid gland: A case report and literature review

A 60-year-old woman presented with a 3-year history of a slow-growing, painless mass in their left parotid gland. Ultrasonography revealed a well-circumscribed, lobulated, hypoechoic mass measuring 19x12x10 mm in the left parotid gland. Computed tomography revealed a well-circumscribed, solid mass with homogeneous enhancement. Fluorodeoxyglucose-positron emission tomography revealed uptake by the tumor but no uptake in other organs, including the nasopharynx. The patient underwent superficial parotidectomy with adequate safety margins and selective neck dissection followed by radiotherapy. No facial paralysis or recurrence of the tumor had been observed as of 20 months post-operation. Histologically, the tumor was composed of sheets of syncytial cancer cells with prominent nucleoli in a dense lymphoplasmacytic background. Epstein-Barr virus (EBV)-encoded RNA in situ hybridization was diffusely positive in the tumor cells. These findings indicated that the tumor was an EBV-associated lymphoepithelial carcinoma. Metastasis, especially from the nasopharynx, was excluded endoscopically and radiologically. Targeted next-generation sequencing of 160 cancer-related genes using the surgical specimen revealed no mutations, including known significant mutations detected in EBV-associated nasopharyngeal carcinoma.

Lymphoepithelial carcinoma of the head and neck: a SEER analysis of prognostic factors for survival

OBJECTIVE

To explore the epidemiological characteristics of patients with lymphoepithelial carcinoma (LEC) of the head and neck and the prognostic factors.

METHODS

We conducted a retrospective cohort study of cases of head and neck LEC retrieved from the Surveillance, Epidemiology and End Results database. Kaplan-Meier survival analysis and the log-rank test were employed to assess overall survival (OS) and cancer-specific survival (CSS). Univariate and multivariate analyses were used to construct Cox regression models. We established nomograms to predict OS and CSS among patients with nasopharyngeal LEC, who were divided into high- and low-risk groups based on the OS nomograms to compare the effects of treatment using the restricted mean survival time (RMST).

RESULTS

The 5-year OS and CSS rates of the cohort were 70.8% and 74.8%, respectively. Advanced age, unmarried status, black race, distant metastasis, and the absence of surgical treatment were significantly associated with decreased survival rates. RMST did not differ between the combined treatment (radiotherapy and chemotherapy) and radiotherapy monotherapy groups, but chemotherapy alone displayed poor efficacy.

CONCLUSIONS

Head and neck LEC is associated with a favorable prognosis. Radiotherapy plays a significant role in managing patients with nasopharyngeal LEC, which is influenced by multiple prognostic factors.

Epstein-Barr Virus (EBV) Epithelial Associated Malignancies: Exploring Pathologies and Current Treatments

Epstein-Barr virus (EBV) is one of eight known herpesviruses with the potential to infect humans. Globally, it is estimated that between 90-95% of the population has been infected with EBV. EBV is an oncogenic virus that has been strongly linked to various epithelial malignancies such as nasopharyngeal and gastric cancer. Recent evidence suggests a link between EBV and breast cancer. Additionally, there are other, rarer cancers with weaker evidence linking them to EBV. In this review, we discuss the currently known epithelial malignancies associated with EBV. Additionally, we discuss and establish which treatments and therapies are most recommended for each cancer associated with EBV.

Lymphoepithelial carcinoma of the parotid gland: Clinicopathological analysis of 146 cases from a single institute

BACKGROUND

Parotid lymphoepithelial carcinoma (LEC) is a rare malignant tumor. The purpose of this study was to investigate the clinicopathological features of parotid LEC.

METHODS

All patients clinicopathological information diagnosed parotid LEC from 2005 to 2017 were analyzed.

RESULTS

A total of 146 cases of parotid LECs were identified. Of these, 126 (86.3%) were primary and 20 (13.7%) were secondary LECs. Patients with secondary LEC tended to have tumors with earlier TNM staging than those with primary (p = 0.031). The tumor cells in 87 (94.6%, 87/92) cases tested positive for Epstein-Barr virus (EBV). Cervical node metastases were present at diagnosis in 46 (31.5%) cases. Overall survival at 5 and 10 years was 97.0% and 90.8%, respectively. Older age was an adverse prognostic indicator for overall survival (p < 0.001).

CONCLUSIONS

Parotid LEC is associated with EBV and an increased rate of cervical node metastases. However, most patients, especially younger ones, have a good prognosis.

Is postoperative radiotherapy an essential treatment for nonmetastatic lymphoepithelial carcinoma of the salivary gland?

BACKGROUND

Lymphoepithelial carcinoma of salivary gland (LECSG) is a rare malignant tumor. Whether postoperative radiotherapy (PORT) can improve locoregional control and which patients can benefit from PORT are unknown. This study aimed to evaluate the role of PORT and provide individualized suggestions for postoperative therapy in patients with LECSG.

PATIENTS AND METHODS

We retrospectively reviewed patients with nonmetastatic LECSG who underwent surgery with or without PORT. Recursive partitioning analysis (RPA) was performed to categorize the patients and predict progression-free survival (PFS).

RESULTS

A total of 223 patients were included, 34 (15.2%) received surgery alone, whereas the remaining 189 (84.8%) underwent PORT in the initial treatment. Although patients in the PORT group were with advanced T stage and N stage, the PORT group had an advantage over the non-PORT group on 1-year, 5-year and 10-year PFS and locoregional control (LRC). PORT was an independent prognostic factor for PFS and LRC. Furthermore, compared with T stage and N stage, the size of the primary tumor and the number of positive lymph nodes were better prognostic predictors. The RPA model was generated according to the endpoint of PFS and categorized patients into 3 prognostic groups: low-risk (maximum diameter of primary lesion (≤3cm) and number of positive lymph nodes (≤2)), intermediate-risk (maximum diameter of primary lesion (>3cm) and number of positive lymph nodes (≤2)), and high-risk (number of positive lymph nodes (>2)), with corresponding 5-year PFS rates of 90.0%, 75.0%, and 51.0%, respectively. Significant improvement in PFS was observed in the PORT group among intermediate-risk (P=0.000) and high-risk patients (P=0.000).

CONCLUSIONS

PORT was shown to be a positive prognostic factor for PFS and LRC of LECSG. PORT was an essential treatment especially for patients with >3cm maximum diameter of primary lesion and/or >2 positive lymph nodes.

Undifferentiated and dedifferentiated head and neck carcinomas

Undifferentiated carcinomas arising at salivary gland and head and neck mucosal sites may originate either de novo or through a process of dedifferentiation of a differentiated carcinoma. While in the latter group the diagnosis is largely dependent on the identification of the differentiated component or recognition of a specific genotype, the classification of undifferentiated carcinomas that lack a differentiated component is mainly based on the identification of specific genetic drivers, like for example the NUTM1 fusions in NUT carcinoma. A further category is represented by virus associated carcinomas (mainly HPV and EBV), that frequently displays an undifferentiated morphology. Overall, these tumors often represent a diagnostic challenge, especially in small biopsies. This review summarizes and discuss the diagnostic approach to the main head and neck carcinoma types that frequently or occasionally display an undifferentiated appearance, with a focus on salivary gland, oropharyngeal, nasopharyngeal and sinonasal subsites.