Nasopharyngeal hyalinizing clear cell carcinoma with EWSR1 rearrangements diagnosed by fluorescence in situ hybridization

Hyalinizing clear cell carcinoma in the nasopharynx: A case report and literature review

RATIONALE

Hyalinizing clear cell carcinoma (HCCC) arising from a minor salivary gland is a rare malignant neoplasm. Most HCCC has been reported in the palate and tongue base, and only rarely in the nasopharynx. Here, we report a rare case of nasopharyngeal HCCC.

PATIENT CONCERNS

A 44-year-old male who complained of otorrhea and aural fullness for 5 years was found to have a nasopharyngeal mass.

DIAGNOSES

HCCC by fluorescence in situ hybridization analysis.

INTERVENTIONS

Surgical resection plus concurrent chemotherapy and radiation therapy were administered.

OUTCOMES

The patient recovered well with symptoms improved at postoperative follow-up.

LESSONS

HCCC should be included in the differential diagnosis of nasopharyngeal mass. Overall, the prognosis of HCCC is positive after tumor resection and adequate management.

Case report: Successful management of primary hyalinizing clear cell carcinoma in nasopharynx: a report of 2 cases and system analysis

Hyalinizing clear cell carcinomas (HCCCs) are infrequent, malignant tumors characterized by their low-grade nature. They typically originate from minor salivary glands. However, these tumors can potentially emerge in any location with minor salivary glands, including the nasopharynx. This report presents two cases of HCCC in females aged 61 and 72 years, with both tumors approximately 4 cm in size. In the first case, a 72-year-old female presented with recurrent bilateral epistaxis. Imaging studies revealed a nasopharyngeal mass, surgically excised, and histopathological analysis confirmed HCCC. Postoperatively, the patient received combined chemotherapy and radiotherapy, achieving a recurrence-free status 2.5 years later. The second case involves a 61-year-old female with a two-year history of bloody nasal discharge. Imaging studies identified a nasopharyngeal lesion, surgically removed, and histopathological examination confirmed HCCC. This patient underwent radiotherapy followed by combination chemotherapy with paclitaxel and carboplatin, displaying no signs of recurrence upon reevaluation after 10 months. These cases highlight the successful management of HCCC through a comprehensive, multimodal approach, integrating surgical intervention and adjuvant therapy. The favorable outcomes emphasize the significance of a thorough treatment strategy for HCCC in the nasopharynx, providing valuable insights for clinicians. Further studies are essential to enhance our understanding of this rare entity and refine treatment protocols for optimized patient outcomes.

Clinical and Histopathologic Analyses of Nasopharyngeal Hyalinizing Clear Cell Carcinoma: A Series of 26 Cases With Molecular Confirmation

The aim of this study was to evaluate the clinicopathologic features, molecular characteristics, treatment strategy, and prognosis of nasopharyngeal hyalinizing clear cell carcinoma (HCCC). Retrospective observational case series. Institutional pathology records between 2006 and 2022 were searched for all cases of nasopharyngeal HCCC. We included 10 male and 16 female patients aged 30 to 82 years (median: 60.5 y, mean: 54.6 y). The most common symptoms were blood-stained rhinorrhea and nasal obstruction. Tumors most often involved the lateral wall of the nasopharynx, followed by the superior posterior wall. Microscopically, all tumor cells were arranged in sheets, nests, cords, and single cells in a hyaline/myxoid/fibrous stroma. The tumor cells were polygonal, with or without distinct cell borders, and displayed abundant clear-to-eosinophilic cytoplasm. All 26 cases were positive for pancytokeratin, CK7, p40, and p63 but negative for myoepithelial differentiation markers. Ki-67 labeling was low and ranged from 1% to 10%. All 26 cases demonstrated EWSR1 and EWSR1-ATF1 rearrangements, and no case demonstrated MAML2 rearrangement. Complete follow-up data were available for 23 patients: 14 patients underwent endoscopic surgery alone, 5 underwent radiation therapy followed by endoscopic surgery, 3 underwent radiation therapy followed by biopsy, and 1 underwent cisplatin chemotherapy before endoscopic surgery. Clinical follow-up ranged from 6 to 195 months; 13 patients (56.5%) were alive without tumor, 5 patients (21.7%) died of disease, 5 patients (21.7%) survived with tumor. HCCCs of the nasopharynx are rare tumors. The definitive diagnosis depends on histopathology, immunohistochemistry, and molecular studies. The optimal treatment for patients with nasopharyngeal HCCC is wide local excision. Radiation and chemotherapy might be good options for managing locally advanced cases. Nasopharyngeal HCCC is less indolent than previously thought. Tumor stage and the choice of treatment are key factors affecting the prognosis of nasopharyngeal HCCC patients.

Clear Cell Carcinoma of Minor Salivary Glands: The Nasopharynx, an Uncommon Site of Origin

Clear cell carcinoma is a rare minor salivary gland neoplasm. Its occurrence in the nasopharynx is uncommon. A limited number of cases are reported in the literature. Here, we report an additional case of clear cell carcinoma of the nasopharynx managed by induction chemotherapy followed by chemoradiotherapy, and we describe the clinical presentation, pathological features, and outcome.

A 63-year-old man presented with an exophytic, ulcerative, and easily hemorrhagic tumor on the left side of the nasopharynx. A diagnosis of primary, cT4N0M0, clear cell carcinoma of the minor salivary gland was confirmed by a core needle biopsy through nasopharyngoscopy and staging procedures. The patient was treated by induction chemotherapy followed by concomitant chemoradiotherapy with clinical benefit and disease stabilization.

Primary salivary gland clear cell carcinoma of the nasopharynx is uncommon. A definitive diagnosis requires an appropriate workup. The optimal treatment is unclear. Chemoradiotherapy might be a good option to manage such cases.

Clear cell carcinoma: a comprehensive literature review of 254 cases

This comprehensive literature review represents a summary of all cases of clear cell carcinoma (CCC) of the salivary glands that are documented in the literature. PubMed was used to collect available reports of CCC; 97 reports detailing 254 cases, published between 1983 and 2020, were retrieved. Clinically the tumor manifests most commonly as a painless mass or swelling on the palate, and the duration of symptoms prior to seeking care ranges from 1 week to 6 years. Local tumor recurrence was present in 18.8% of the cases. By histopathology, CCC shows a mixture of growth patterns including solid (25.1%), nested (78.6%), sheet-like (23.5%), cords (46.1%), and trabeculae (42.4%). Immunohistochemical studies are positive for one or more cytokeratins (99.1%), PAS (95.1%), EMA (77.8%), and p63 (96.3%), but negative for S-100 (96.3%), PASD (91.1%), SMA (91.0%), and calponin (95.1%). Molecular features were reported in 113 cases; 96.0% were positive for an EWSR1 rearrangement by EWSR1 break apart FISH testing and 14.8% were positive for the rearrangement EWSR1-ATF1 tested by qPCR or targeted RNA sequencing. Clinical patterns and genetic studies imply that this tumor is the extraosseous counterpart of clear cell odontogenic carcinoma, an intraosseous odontogenic tumor of the jaws.

Integrative sequencing discovers an ATF1-motif enriched molecular signature that differentiates hyalinizing clear cell carcinoma from mucoepidemoid carcinoma

OBJECTIVES

Salivary gland tumors are comprised of a diverse group of malignancies with widely varying prognoses. These cancers can be difficult to differentiate, especially in cases with limited potential for immunohistochemistry (IHC)-based characterization. Here, we sought to define the molecular profile of a rare salivary gland cancer called hyalinizing clear cell carcinoma (HCCC), and identify a molecular gene signature capable of distinguishing between HCCC and the histopathologically similar disease, mucoepidermoid carcinoma (MEC).

MATERIALS AND METHODS

We performed the first integrated full characterization of five independent HCCC cases.

RESULTS

We discovered insulin-like growth factor alterations and aberrant IGF2 and/or IGF1R expression in HCCC tumors, suggesting a potential dependence on this pathway. Further, we identified a 354 gene signature that differentiated HCCC from MEC, and was significantly enriched for genes with an ATF1 binding motif in their promoters, supporting a transcriptional pathogenic mechanism of the characteristic EWSR1-ATF1 fusion found in these tumors. Of the differentially expressed genes, IGF1R, SGK1 and SGK3 were found to be elevated in the HCCCs relative to MECs. Finally, analysis of immune checkpoints and subsequent IHC demonstrated that CXCR4 protein was elevated in several of the HCCC cases.

CONCLUSION

Collectively, our data identify an ATF1-motif enriched gene signature that may have clinical utility for molecular differentiation of HCCCs from other salivary gland tumors and discover potential actionable alterations that may benefit the clinical care of recurrent HCCC patients.

A contemporary update on hyalinizing clear cell carcinoma: compilation of all in-house cases at our institution and a literature review spanning 2015-2020

Tumors of the head and neck with clear cell features prompt a broad differential diagnosis. A relatively uncommon, but increasingly recognized, entity is hyalinizing clear cell carcinoma (HCCC). This neoplasm, first described in 1994, consists of clear cells arranged in nests or trabecule with a hyalinized stroma. These are low-grade neoplasms that only infrequently metastasize and rarely recur. They also often harbor a unique EWSR-ATF1 gene rearrangement. As the prognosis is excellent compared with other clear cell neoplasms, the correct diagnosis is key. Here we present all of the cases of HCCC in the past decade from our institution alongside a comprehensive literature review spanning 2015-2020 to further characterize this unusual malignancy.

Does Nodal Metastasis and Perineural Invasion Affect Local Control in Hyalinizing Clear Cell Carcinoma of the Oral Cavity? A Case Report with Long Term Follow-Up

Hyalinizing clear cell carcinoma (HCCC) is a rare, low-grade neoplasm accounting for approximately 1% of salivary gland neoplasms. Histologically, it is characterized by a monomorphous population of clear cells arranged in sheets, nests, or cords, lacking ductal structures. Until recently, clear cell carcinoma of the oral cavity (OC) represented a diagnosis of exclusion when other head and neck pathologic entities such as epithelial-myoepithelial carcinoma or mucoepidermoid carcinoma could be ruled out, making definitive diagnosis by light microscopy and immunoprofiling a challenge. As a result, initial biopsies are often misclassified, and could result in under- or overtreatment. More recently, the presence of the EWSR1-ATF1 gene fusion has been adopted to definitively diagnose HCCC. Typically, HCCC demonstrates clinical indolence and responds well to curative surgical excision alone for localized disease, with adjuvant radiotherapy (RT) reserved for high risk features including perineural invasion, lymphovascular invasion, and regional cervical metastasis. The literature, however, lacks consensus regarding the role of adjuvant radiotherapy. In this article, we report a case of HCCC in a rare site involving the ventral tongue, with high risk features of perineural invasion and cervical nodal metastasis. The patient underwent surgical excision alone; declining adjuvant radiotherapy despite the high risk features, and was alive with no evidence of disease at the 42-month mark. Furthermore, we provide an update on the current prognostic indicators for HCCC, and emphasize the need for chromosomal analysis to achieve a definitive diagnosis.

Nasopharyngeal Hyalinizing Clear Cell Carcinoma: A Case Report and Review of the Literature

Background

Hyalinizing clear cell carcinomas (HCCCs) are rare, low-grade, malignant tumors which most often arise from the minor salivary glands primarily in palate and tongue but can arise in any location with minor salivary glands including the nasopharynx.

Methods

A case report of primary nasopharyngeal HCCC is presented. Because of the rarity of this tumor and location, a literature search was conducted to determine the most common presenting symptoms, treatment strategies, and outcomes.

Results

A 48-year-old man underwent biopsy of a 4.5 cm mass of the right nasopharynx with pathology suggesting an intermediate grade mucoepidermoid carcinoma. After discussing management with the patient, an endoscopic resection was performed. Final pathology revealed an HCCC which was confirmed after negative Mastermind-like 2 (MAML2) and positive Ewing sarcoma breakpoint region 1 (ESWR1) gene rearrangements on fluorescence in situ hybridization (FISH) studies. Literature review of other nasopharyngeal HCCC cases shows diverse presentation and overall excellent prognosis through surgical and radiation therapy.

Conclusion

HCCCs are rare, low-grade malignant tumors of the minor salivary glands and can present as a nasopharyngeal mass. Presenting symptoms are diverse but frequently involve otologic and sinonasal disturbances. HCCC is an indolent tumor with an excellent prognostic outcome when treated appropriately with surgical resection and adjuvant radiotherapy.

Hyalinizing clear cell carcinoma of salivary glands: A retrospective study focused on uncommon morphology, immunohistochemistry, and detection of gene fusion using fluorescence in situ hybridization

AIMS

To investigate histological, immunohistochemical, and molecular features, especially uncommon morphology of hyalinizing clear cell carcinoma (HCCC) to expand the morphological spectrum of HCCC.

METHODS AND RESULTS

We examined 5 cases of HCCC by histological, immunohistochemical, and molecular analysis. Generally, 5 HCCC cases shared similar characteristics, exhibiting clear to slightly eosinophilic cells arranged in cords, nests, islands, or trabeculae with a hyalinized stroma, while myxoid stroma, perineural invasion, and polygonal cells with high-grade nuclei were observed in 3 cases. Immunohistochemically, 5 cases were entirely immunoreactive for CKpan, whereas 80% HCCC cases were positive for P63, and CK14. None expressed immunoreactivity for S-100, Calponin, or GFAP. The positive rate of Ki-67 staining was about 5% in the classic area of case 3, but 40% in the high-grade area. As for the result of FISH findings, EWSR1 gene break was detected in all 5 HCCC cases.

CONCLUSIONS

Our study has expanded the morphological spectrum of HCCC, and proposed the diagnosis of HCCC should be confirmed by fully analyzing histological, immunohistochemical, and molecular features practically.

Primary paranasal sinus clear cell carcinoma with EWSR1-ATF1 fusion: report of 2 molecularly confirmed cases exhibiting unique histopathology

Hyalinizing clear cell carcinoma (HCCC) is a rare low-grade tumor of the salivary glands made up of clear cells that form cords and nests in hyalinized stroma. To date, primary HCCCs of the paranasal sinus have not been described. This article presents 2 cases of HCCC of the maxillary sinus with unusual glandular formation and lymphoplasmacytic stroma in case 1 and a characteristic solid nest pattern and fibrocellular and hyalinized stroma in case 2. Immunohistochemical studies excluded myoepithelial origin and sinonasal renal cell-like adenocarcinomas. Negativity for p63 and p40 in case 1 ruled out a squamous cell origin. Both cases showed a rearranged EWSR1 gene. Reverse-transcription polymerase chain reaction detected EWSR1-ATF1 fusion gene transcripts, and Sanger sequencing confirmed an EWSR1 exon 11 fused in-frame to ATF exon 3.