Microsatellite Instability in Nasopharyngeal and Lymphoepithelial Carcinomas of the Head and Neck

Lymphoepithelial Carcinoma Originated from the Sinonasal Cavity: Case Report and Literature Review

Background

Sinonasal lymphoepithelial carcinoma (SNLEC) is a rare neoplasm, representing less than 1% of all types of carcinomas and approximately 3% of head and neck tumors. It can affect the nasopharynx due to the rich lymphoid tissue present in this region. Clinical SNLEC presentation varies, ranging from asymptomatic to nonspecific sinonasal symptoms. We report a case of SNLEC and review the literature for SNLEC presentation, diagnosis, management options, and outcomes. Case Presentation. A 38-year-old male, medically free, presented to the emergency department complaining of nasal obstruction, right facial numbness, persistent right-sided headache, intermittent orbital pain, and a history of on/off epistaxis. Imaging showed a destructive mass in the right sphenoid sinus extending to different sinuses and infratemporal fossa. Biopsy confirmed the diagnosis of SNLEC, with immunohistochemistry being positive for Epstein-Barr virus (EBV) and CK8/18. Induction chemotherapy was started with three cycles of cisplatin and gemcitabine, followed by concurrent chemoradiation therapy.

Conclusion

SNLEC is rare, with limited reported cases from around the world. It is mostly seen in adults between their fifth and seventh decades with male predominance. SNLEC is diagnosed using imaging, immunohistochemistry, and EBV testing given its strong association with EBV. Owing to the limited cases, there is no standard approach to treating SNLEC. However, most cases managed with radiation and with and without other modalities showed an excellent response in terms of tumor nonrecurrence.

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.

A Case Report of Tongue Lymphoepithelial Carcinoma with a Histological Diagnostic Dilemma

Most head and neck lymphoepithelial carcinomas (LECs) arise in the nasopharynx and harbor Epstein–Barr virus (EBV). LEC is also a rare subtype of the oral squamous cell carcinoma (SCC). Morphologically, LEC is defined as resembling non-keratinizing nasopharyngeal carcinoma, undifferentiated subtype. The histological features and pathogenesis of oral LEC are not established. We describe a case of tongue LEC with histopathological diagnostic difficulties. A 72-year-old Japanese female presented with a whitish change on her left-side tongue. The diagnosis was atypical epithelium; neoplastic change could not be ruled out by a biopsy. Although the lesion was monitored at our hospital per her request, invasive carcinoma was detected 11 months later. Microscopically, conventional SCC was observed with the characteristic features as LEC confined to the deep part of the lesion. We briefly discuss this unusual histological finding and make a novel proposal for distinguishing oral LEC from LECs in other regions based on these histological findings.

Lymphoepithelial carcinoma of the maxillary sinus: A case report and review of the literature

RATIONALE

Most cases of lymphoepithelial carcinoma (LEC) occur in the nasopharynx, and LEC in the sinonasal tract is extremely rare; thus, the clinical characteristics of sinonasal LEC are not well known.

PATIENT CONCERNS

A 63-year-old Japanese man presented with a three-week history of left cheek pain, nasal obstruction and cheek swelling.

DIAGNOSES

Enhanced CT and MRI revealed a tumor of the left maxillary sinus that invaded the left orbit and hard palate, with multiple swollen left cervical lymph nodes. Open biopsy was performed, and the specimen was diagnosed as LEC.

INTERVENTIONS

Alternating chemoradiotherapy (ALCRT) followed by salvage surgery was performed.

OUTCOMES

Our patient has been disease free for 5 years.

LESSONS

A literature review of the epidemiology, etiology, clinical course and management of sinonasal LEC is highlighted. We believe ALCRT followed by salvage surgery to be a highly optimal treatment for sinonasal LEC from the viewpoint of a balance between quality of life and a high curative effect.

Programmed Death-Ligand 1 Expression, Microsatellite Instability, Epstein-Barr Virus, and Human Papillomavirus in Nasopharyngeal Carcinomas of Patients from the Philippines

Most nasopharyngeal carcinomas (NPCs) in a high-incidence population are driven by Epstein-Barr virus (EBV) infection. EBV-associated malignancies have increased expression of the programmed death-ligand 1 (PD-L1). Immunotherapy agents targeting the PD-1/PD-L1 pathway have achieved durable treatment effects in patients with various cancer types including EBV-associated malignancies. In this study, we sought to investigate PD-L1 expression in a cohort of patients with NPCs from the Philippines. Fifty-six NPCs were studied for PD-L1, p16, and DNA mismatch repair (MMR) deficiency by immunohistochemistry. One case with MMR deficiency was also assessed for microsatellite instability (MSI) by polymerase chain reaction. EBV and human papillomavirus (HPV) status were tested by in situ hybridization. All NPCs were p16 negative. Three of the 56 NPCs (5%) were EBV negative (EBV-) and HPV negative, while one NPC (1/56, 2%) was EBV positive and showed MSI (EBV+/MSI). Positive PD-L1 expression (PD-L1+), defined as membranous staining in ≥1% tumor cells, was seen in 64% (36/56) of NPCs. All three EBV- NPCs were PD-L1+ as was the EBV+/MSI NPC. PD-L1+ was seen significantly more often in NPCs from non-smokers than those from smokers (23/28, 82% vs 9/18, 50%; P = 0.047). PD-L1+ was not associated with pT, pN, distant metastasis, or clinical stage (P > 0.05). PD-L1+ was not associated with overall survival (P = 0.473). In summary, our results show frequent PD-L1 expression in NPCs regardless of EBV status and a preferential PD-L1 expression in non-smokers. MSI and HPV positivity are exceedingly rare in NPCs.

Lymphoepithelial carcinoma in the maxillary sinus: a case report

Introduction

Lymphoepithelial carcinoma of the maxillary sinus is a very rare malignancy and it can be difficult to make a pre-operative diagnosis.

Case presentation

A 72-year-old Caucasian woman presented to our facility with an isolated right-side epistaxis that had been present for three months, with the results of a computed tomography scan showing a soft tissue mass in the right maxillary sinus with an impacted tooth. The results of a transnasal endoscopic biopsy were compatible with a lymphoepithelial carcinoma, following which our patient underwent a radical excision of the mass. The final histology results revealed lymphoepithelial carcinoma of the maxillary sinus with negative assays for Epstein-Barr virus. Our patient was given post-operative external radiotherapy and has remained disease-free at three-year follow-up.

Conclusions

This report details the diagnosis and management of a case of lymphoepithelial carcinoma of the maxillary sinus, which is a very rare malignant tumor with very little mention in the literature. Only a strong suspicion with systematic use of various patho-immunological tests helps to arrive at a definitive diagnosis by excluding other better-known tumors.

[Lymphoepithelial carcinoma of the conjunctiva: an unusual location]

Lymphoepithelial carcinoma is an undifferentiated carcinoma associated with a lymphocytic infiltration and constitutes a rare category of malignant neoplasms that share morphologic features with undifferentiated nasopharyngeal carcinoma. Its pathogenic aspects remain unknown and it has been described at several sites, but it is rarely found in the conjunctiva. We report a case in a patient aged 66, revealed by a tumefaction of the internal angle of the left eye. The initial examination found a tumoral lesion in the medial canthus, extending to the medial half of the lower eyelid and a preauricular lymphadenopathy. Facial computed tomography scan showed that the lesion was responsible for an osteolysis of the medial wall of the left orbit. Histologic examination showed a proliferation of undifferentiated tumour cells with an intratumoral lymphocytic infiltrate. Immuno-histochemical evaluation led to a diagnosis of lymphoepithelial carcinoma (cytokeratin 7+, cytokeratin 20+, vimentin-). No Epstein-Barr viral genomic sequences were detected by in situ hybridization. Nasofibroscopy was normal. Treatment was a wide excision with enucleation, followed by 50 Gy external radiotherapy. After a follow-up period of 18 months, the patient was still in a situation of complete remission.

Undifferentiated carcinoma of the oropharynx: a human papillomavirus-associated tumor with a favorable prognosis

Undifferentiated carcinoma (undifferentiated carcinoma, nasopharyngeal type, or lymphoepithelial carcinoma) is an uncommon and histologically distinct tumor in the oropharynx, which in Western countries, has been clearly shown not to harbor Epstein Barr virus (EBV). We sought to analyze these tumors for human papillomavirus (HPV) and to examine their clinical outcomes. All cases of oropharyngeal carcinoma diagnosed as 'undifferentiated' or 'lymphoepithelial' were retrieved from the department files at Barnes-Jewish Hospital. After consensus review by all three study pathologists, 16 were found to have diagnostic histological features and to lack distinguishing characteristics of other oropharyngeal cancers. Immunohistochemistry for p16 and p53 and in-situ hybridization for HPV and EBV encoded small RNA were performed. p16-positive but HPV in situ hybridization-negative cases were analyzed by polymerase chain reaction for high-risk HPV types. The results were correlated with pathological findings and clinical follow up. There were 16 patients. The average age was 59.2 years, 14 patients (88%) were smokers, and 13 (81%) had nodal metastases. In all, 14 cases (88%) were p16 positive and 15 (94%) were HPV positive by in situ hybridization and/or polymerase chain reaction. All cases were negative for EBV, and p53 was overexpressed in five (33%), four of which were HPV positive. Disease recurred in only three patients and two of these died with disease at 38 and 136 months, respectively. Three year overall, disease-free, and disease-specific survival rates were 54, 78, and 100%, respectively. In summary, in our patient population, the majority of oropharyngeal undifferentiated carcinomas harbor transcriptionally active HPV but not EBV. Almost all overexpress p16, and few have p53 overexpression. Disease-specific survival is comparable to published rates for other HPV-related oropharyngeal squamous cell carcinoma variants and is better than that of HPV-negative carcinomas.

Lymphoepithelial carcinoma: two case reports and a systematic review of oral and sinonasal cases

Lymphoepithelial carcinoma (LEC) is a rare malignancy. Histologically, it is an undifferentiated carcinoma with an intermixed reactive lymphoplasmacytic infiltrate. Herein, we report two cases of LEC in the head and neck region that presented to Oulu University Hospital. Our first case is a 30-year-old man with LEC in the left maxillary sinus. The second case is a 49-year-old man with LEC in the soft palate and uvula with regional lymph node metastases at diagnosis. In addition, a systematic review of the literature from 1980 to 2010 was performed with MEDLINE and cross-references were searched manually. Case reports and clinical series of oral, oropharyngeal, nasal, and paranasal sinus LECs were reviewed revealing a total of 110 cases. Most of the oral cases were found in the tonsils (n = 29), oropharynx (n = 19), and in oral mucosa (n = 18), while sinonasal cases (n = 40) were mainly in the paranasal sinuses and nasal cavity. From 37 case reports, including ours, the median age was 58 and 62 years for sinonasal and oral/oropharyngeal LECs, respectively. Oral and oropharyngeal LECs have a 70.0% tendency to metastasize and 16.6% spread locally. In contrast, none of the nasal and paranasal LECs metastasized, but 60% spread locally. Epstein-Barr virus (EBV) had been detected in 87.5% of all tested LEC cases. Treatment of LECs, during the last decade, has largely consisted of surgery, combined with radiotherapy or chemoradiation. Although local spread or nodal metastases are fairly common at the time of diagnosis, the mortality rate of adequately treated LEC patients is low.

Lymphoepithelial carcinoma of the maxillary sinus with orbital invasion

Lymphoepithelial carcinoma (LEC) of the maxillary sinus is a very rare neoplasm that shares some characteristics with nasopharyngeal carcinoma. Epstein-Barr virus (EBV) has been reported to be associated with LEC located outside of the nasopharynx in Asian populations. A case report of a 64-year-old Asian female with right-sided cheek mass which was diagnosed preoperatively as a maxillary mass by paranasal sinus computed tomography scan is presented. Because maxillary sinus cancer with orbital invasion was considered, she underwent surgical removal of a mass. Final pathology revealed LEC, which is presented in our report. However, in situ hybridization assays returned negative results for Epstein-Barr virus. The patient underwent postoperative chemoradiotherapy, and has remained disease-free during 3-year follow-up. Although a few cases in the maxillary LEC have been reported, this is the first report describing the diagnosis and treatment of LEC occurred in the maxillary sinus. Surgical removal and adjuvant chemoradiotherapy may be useful in the treatment of more advanced maxillary LEC.

Molecular diagnosis in head and neck: what a surgical pathologist must know

Molecular alterations in tumors have become interesting targets both for diagnostic and for therapeutic and prognostic applications in tumor pathology. In the head and neck, there are a variety of different alterations, encompassing all the different types of genetic events associated with carcinogenesis. This paper reviews three different types of tumors that display a spectrum of genetic alterations: the translocation in Mucoepidermoid carcinoma, Epstein Barr virus association in nasopharyngeal carcinoma, and the HRPT2 tumor suppressor gene in parathyroid carcinoma. Basic histology is reviewed and the genetic alterations are discussed, along with a brief discussion of potential diagnostic implications.

Investigation of allelic imbalances on chromosome 3p in nasopharyngeal carcinoma in Tunisia: high frequency of microsatellite instability in patients with early-onset of the disease

Tunisia is one of the world's intermediate risk areas for nasopharyngeal carcinoma (NPC). Loss of heterozygosity (LOH) on the short arm of chromosome 3 (3p) is the most frequent genetic change reported in NPC from endemic areas. In the present study, we investigate the incidence of LOH and microsatellite instability (MSI) on chromosome 3p in 49 microdissected primary NPC specimens and corresponding non-cancerous tissues from Tunisian patients using six microsatellite polymorphic markers. LOH at one or more markers was observed in 40 out of 48 informative cases (83.3%). The markers D3S1038 at 3p25.2-26.1 and D3S1076 at 3p21.1-21.2 have showed the highest frequency of LOH (51.3%), followed by D3S1067 at 3p14.3-21.1 (48.7%), D3S1568 at 3p21.3 (47.4%), D3S659 at 3p13 (15.3%), and D3S1228 at 3p14.1-14.2 (11%). Interestingly, MSI at one or more microsatellite markers was observed in 15 cases (31.2%). The highest frequency of MSI was presented by D3S1568 (18.4%), D3S1067 (17.9%), and D3S1038 (12.8%). With regard to clinicopathological features, LOH was found to be less common in young patients (under 25 years) than in adults (p=0.04), whereas MSI was found to be more frequent in patients under 45 years than in older patients (p=0.006). No significant correlation was found between LOH or MSI and the other clinicopathological features investigated including, gender, tumor size, lymph node metastasis, UICC clinical stage, and histological subtype. This study revealed different patterns of allelic imbalance on chromosome 3P in NPC between age groups in Tunisia, and suggests an alteration in the DNA mismatch repair machinery that may be, in part, responsible of the early age onset form of this disease in North African populations. More attention should be given to the mismatch repair system in the juvenile form of this disease in future studies.