Primary parotid lymphoepithelial carcinoma: A case report and literature review of a rare pathological entity

First Case Report of Bilateral Parotid Lymphoepithelial Carcinoma

Background/Aim

The parotid is the largest salivary gland and is located anteriorly to the sternocleidomastoid muscle and laterally to the ramus of the mandible. Neoplasms in this gland are relatively rare, with 80% being benign and 20% malignant, primarily represented by mucoepidermoid carcinoma. In the head and neck region, lymphoepithelial carcinoma (LEC) accounts for 0.4% of malignant salivary gland tumors.

Case Report

A 35-year-old man with no previous comorbidities was admitted to a Head and Neck Surgery Specialty Service for a painless right cervical mass of uncertain growth. Extensive diagnostic investigation revealed involvement of the contralateral parotid, associated with systemic lymph node enlargement. Thus, adjuvant radiotherapy was decided by the treating team.

Conclusion

This case confirms the heterogeneous features and distinctive behavior that the disease can present, as seen with bilateral parotid LEC.

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.

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.

Could definitive radiotherapy be a treatment option for lymphoepithelial carcinoma of major salivary gland: Comparison of clinical outcomes of upfront surgery and upfront chemoradiotherapy

OBJECTIVES

The optimal treatment and associated clinical outcomes for lymphoepithelial carcinoma of the major salivary gland (LECSG) are currently unclear. As such, the purpose of this study was to assess the survival rates of LECSG patients who received either upfront surgery or upfront chemoradiotherapy (CRT).

MATERIALS AND METHODS

In this retrospective study, we analyzed cases of LECSG patients treated at our center from January 2010 to April 2021. The cumulative incidences of overall survival rate (OS) and locoregional failure-free survival rate (LRFFS) were evaluated using the Kaplan-Meier method. In order to balance potential risk factors between the treatment groups, we conducted propensity score matching (PSM) at a 1:1 ratio.

RESULTS

The study enrolled a total of 107 patients, among whom 24 received surgery alone, 56 underwent surgery combined with postoperative radiotherapy, and 27 underwent definitive radiotherapy. The 5-year LRFFS rate and 5-year OS rate for the entire cohort were 86.6% and 84.4%, respectively. Following PSM, the 5-year LRFFS and OS rates for the upfront CRT cases were comparable to those of upfront surgery, both before and after matching. However, the upfront surgery group showed a tendency toward more de novo facial nerve injury and post-treatment facial nerve injury.

CONCLUSION

The results of this study suggest that upfront CRT is as effective as upfront surgery in terms of locoregional control and overall survival for LECSG patients. Therefore, upfront CRT could be considered a viable treatment option, potentially avoiding the risks associated with surgical intervention.

Clinical features and treatment outcome of lymphoepithelioma-like carcinoma from multiple primary sites: a population-based, multicentre, real-world study

BACKGROUND

Lymphoepithelioma-like carcinoma (LELC) is a rare and unique subtype of cancer that histologically resembles undifferentiated nasopharyngeal carcinoma (NPC). The population-based analysis of LELC and the optimal treatment remains unclear.

MATERIALS AND METHODS

This real-world, retrospective study investigated 770 patients with LELC for primary site, treatment, and survival outcomes from 2005 to 2019 from five cancer centres in China. The overall survival (OS) of different subgroups was appraised by log-rank tests and Kaplan-Meier analysis.

RESULTS

Primary sites LELC included the lung (597 cases, 77.5%), salivary gland (115 cases, 14.9%), and others. The median progression-free survival (PFS) of LELC patients was 47.4 months. The median overall survival (OS) was not reached. The 5-year survival rate for LELC patients was 77.8%. Most patients in stages I and II received surgery. The majority of patients in stage III received surgery and radiotherapy. More than half of the patients in stage IV received chemotherapy. Among relapsed or metastatic cases receiving chemotherapy, patients who received immunotherapy at any time presented with a superior OS than those without immunotherapy (P < 0.0001, HR = 0.39, 95% CI 0.25-0.63). Compared with the SEER database, patients with LELC had a better prognosis than NPC, with a 5-year overall survival of 77.3% vs. 56.8% (P < 0.001).

CONCLUSION

Our data provide treatment patterns and outcomes for LELC from various primary sites. Randomized controlled studies are necessary to further define the standard of care for patients with LELC. Trial registration This clinical trial was registered at ClinicalTrials.gov (No. NCT04614818).

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.

Lymphoepithelial carcinoma in the sublingual gland

Lymphoepithelial carcinoma is rare in the salivary glands, with an incidence of 0.4%. The most commonly affected site is the parotid gland, followed by the submandibular gland. Lymphoepithelial carcinoma in the sublingual gland has been reported only four times in the existing English-language literature. Such tumours are characterized by the presence of a poorly differentiated carcinoma that is surrounded and infiltrated by lymphocytes, and they are strongly associated with Epstein-Barr virus infection, patient ethnicity, and prominent radiosensitivity. Wide surgical excision combined with adjuvant therapy has been suggested as the first-choice therapeutic regimen. This report describes the case of a 34-year-old Indonesian woman who was evaluated and treated in Taipei Medical University Hospital. She had a tumour that presented as a painless swelling on the floor of the mouth. The diagnosis was confirmed by conducting an incisional biopsy, and a wide surgical excision with bilateral supraomohyoid neck dissection and free flap reconstruction was performed. The patient also underwent adjuvant chemoradiotherapy. No evidence of local recurrence or distant metastasis was detected during the 6 months of follow-up. Subsequently, the patient returned to her home country, and further follow-ups were not conducted.

Clinical analysis of 12 patients with primary lymphoepithelial carcinoma of the parotid gland

BACKGROUND AND PURPOSE

The WHO recently designated salivary gland lymphoepithelial carcinoma as a unique malignant tumor that most commonly occurs in the parotid gland. This is a rare cancer and there are few reports in the literature. Among 854 patients with parotid gland tumors who were admitted to our institution, we diagnosed 12 patients (1.41%) with parotid lymphoepithelial carcinoma.

METHODS

Retrospective analysis of 12 patients with parotid lymphoepithelial carcinoma diagnosed by the Department of Pathology, Xiangya Hospital of Central South University.

RESULTS

All 12 patients had unilateral parotid gland disease and 8 had cervical lymph node metastasis. Five patients received PCR testing for the Epstein-Barr virus and two were positive. All patients received surgical treatment, two received surgical resection alone, nine received surgery and postoperative radiotherapy and chemotherapy, and one received surgery and postoperative chemotherapy. The postoperative follow-up time ranged from 13 to 77 months. As of the last follow-up, eight patients were tumor-free, one patient was lost to follow-up, and three patients died. The main cause of death was local tumor recurrence and multiple metastases throughout the body.

CONCLUSION

Parotid lymphoepithelial carcinoma is a malignant neoplasm characterized by proliferation, invasion, and inclusion of poorly differentiated or undifferentiated carcinoma, and a high rate of metastasis to ipsilateral cervical lymph nodes. The comprehensive treatment method consists of radical resection combined with postoperative radiotherapy and chemotherapy. After this comprehensive treatment, the 1-year, 3-year, and 5-year overall survival rates of our patients were 100%, 78.8%, and 39.4%.